Consensus-Based Droop Control Synthesis for Multiple DICs in Isolated Micro-Grids Lin-Yu Lu,Student Member,IEEE,and Chia-Chi Chu,Member,IEEE
Abstract—The task of autonomous power sharing in a micro-grid is usually achieved by decentralized droop control on individual interface power converters,which may suffer from the dependence on output line impedances.Inaccurate reactive power sharing will occur under strongly non-uniform line imped-ances.Due to inherently distributed and heterogeneous nature of the micro-grid,it becomes an ideal platform for applications of consensus control algorithms.In this paper,the consensus-based droop control with sparse communication network is proposed to overcome the drawback of existing droop control methods.In particular,when line impedances of the power grid are either lossy with the uniform ratio or even pure resistive,the consensus droop control is still an effective method for autonomous real and reactive power sharing.In addition,closed-loop system stability of the proposed consensus-based droop control method can be ensured by the energy function approach under certain conditions. Real-time simulations of two micro-grid systems are studied to validate the feasibility of the proposed consensus-based droop control method.
Index Terms—Consensus algorithm,droop control,energy func-tions,micro-grid,real-time simulations.
I.I NTRODUCTION
W ITH recent advocating of integrating distributed re-newable energy resources(DERs)in the area of smart grids,the micro-grid has been proposed and demonstrated as an effective technology to integrate DERs into the existing power grid through DERs interface power converters(DICs)[1]. Traditionally,both real power-frequency(-)droop control and reactive power-voltage magnitude(-)droop control are adopted for decentralized power sharing among DICs[2], [3],which mimics the operation of conventional synchronous generators[4].However,the performance of reactive power sharing under-droop control may be deteriorated due to its dependence on output line impedances[5]–[7].In[7],the quadratic droop control has been developed for the stabilization of micro-grid voltages.In order to provide more accurate reactive power sharing,the-droop control method has been proposed recently[8].The idea of the load dependence
Manuscript received September10,2013;revised January21,2014,May12, 2014,and August22,2014;accepted November02,2014.Date of publication November26,2014;date of current version July17,2015.This work was sup-ported in part by the Ministry of Science and Technology,Taiwan,R.O.C.,under Grant NSC102-2221-E-007-074,NSC103-ET-E-007-002-ET,and MOST103-3113-E-002-014.Paper no.TPWRS-01166-2013.
The authors are with the Department of Electrical Engineering,National Tsing Hua University,Hsinchu300,Taiwan(e-mail:s100061805@m100.nthu. edu.tw;ccchu@https://www.doczj.com/doc/8d3054851.html,.tw).
Color versions of one or more of the?gures in this paper are available online at https://www.doczj.com/doc/8d3054851.html,.
Digital Object Identi?er10.1109/TPWRS.2014.2368135on the time derivative of the voltage phasor magnitude was originated from dynamical load modelings proposed by[9]. Later,the reactive power control actions considering have been developed in[10]–[13].These control strategies are es-sentially based on control Lyapunov functions and can achieve the damping of system voltages via locally measurable quan-tities.The reactive power sharing under-droop control is then independent of the output line impedances.Nevertheless, only the small signal stability analysis has been studied in[8], nonlinear characteristics of-and-droop control in the autonomous micro-grid have not be completely investigated. In order to capture nonlinear dynamical behaviors of the micro-grid even under large disturbances,the small-signal analysis of the-droop control has been extended into the nonlinear system framework in[14].In this paper,the energy function(EF)of the bulk micro-grid will be considered as analysis tools to ensure proper multiple power sharing even under strongly non-uniform lossy transmission lines.Under this framework,the entire closed-loop system with multiple DICs is similar to the quasi-gradient system.Nevertheless,it has also been revealed that the-and-droop control still results in inaccurate power sharing under large load disturbances. This is due to possible existence of non-isolated equilibrium points in the closed-loop system.Additional control efforts are necessary to overcome this dif?culty.
In recent years,consensus-based multi-agent control theory has been widely investigated in various?elds[15]–[18].The main objective of this consensus control is to achieve general agreements among all agents in a network with considering certain desirable states of the entire https://www.doczj.com/doc/8d3054851.html,munica-tion infrastructure of a multi-agent network is often limited to only local information exchange available.Discovery of the global information is promised by the average consensus theorem[15].Since the consensus algorithms require only neighbor-to-neighbor interactions,marvellous robustness can be achieved.
Several attempts have been made to utilize consensus-based control algorithms for smart grid applications,including1) voltage support on distribution feeders[19],[20];2)smart economic dispatch[21],[22];3)smart load shedding[23];
4)synchronous generator based micro-grid[24];and5)in-verter-based power sharing[25]–[27].The ratio-consensus algorithm is utilized to ensure that individual capacity con-straints of generators are met within a micro-grid in[24].The power constraints of transmission lines are enforced in the consensus manner based on the measured line?ow in[25]. However,the control over reactive power and bus voltage are
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not addressed.Recently,an additional control mechanism is in-troduced in[26],where droop controlled inverters are stabilized through a wireless communication network.However,the sta-bility analysis is restricted to the scope of small-signal.In[28], a fully-distributed consensus-based algorithm is proposed to achieve power supply-demand balance within an autonomous micro-grid.In order to achieve active power sharing of multiple doubly-fed induction generators,the average consensus the-orem is also employed in[29]to discover information among control agents.
The pioneer work of consensus-based droop control for autonomous power sharing in a micro-grid was studied recently by[27],[30],and[31].Comprehensive nonlinear stability analysis of the closed-loop system under consensus-based -droop control were developed.Numerical experiments of two DICs sharing one single load were performed to verify feasibility of the proposed consensus-based-droop control. Although these works provide foundations for consensus-based droop control,the relationship of reactive power sharing with respect to the voltage control was not considered.
In this paper,we will extend the consensus-based-droop control to consensus-based--droop control.It will be shown that if dynamic behaviors of a micro-grid is modeled by the network-preserving model with the uniform ratio line impedances,the closed-loop system under the consensus-based --droop control is quasi-gradient with the bounded below EF[32].Thus,the consensus-based--droop control is an effective way for multiple power sharing even under large disturbances.In addition,the above approach can also be extended to the micro-grid with predominantly resistive lines for low-voltage distribution grids if the consensus-based --droop control is activated.
The rest of this paper is organized as follows.Section II will provide the technical background,including mathematical preliminaries,structure-preserving models for power grids,and dynamical scenarios of droop control for isolated micro-grids. Section III will describe micro-grid droop control mechanisms in structure-preserving models.Conventional droop control methods will also be examined in this structure-preserving model.Recent droop-control methods,including1)--droop control,and2)droop control with both frequency and voltage restorations,will be investigated by the EF approach in Section IV.The proposed consensus-based--droop control is then illustrated in Section V.Simulation studies on 7-bus and14-bus micro-grid systems,which are part of the IEEE69-bus distribution system[33],[34],will be presented in Section VI to validate effectiveness of the consensus-based --droop control even under large disturbances.Fi-nally,some conclusions and future research directions will be addressed in Section VII.
II.B ACKGROUND
In this section,concepts about stability regions of the general nonlinear system and EFs will be reviewed?rst[35]–[37].Next, dynamical model descriptions of micro-grids will be examined. Finally,applications of EFs for droop-control in isolated micro-grids will be formulated.A.Mathematical Preliminaries
Considering the following nonlinear system:
(1) where belongs to.A state vector is called an equilib-rium point(EP)of(1)if.We say that an EP of(1)is hyperbolic if the Jacobian of at,denoted as,has no eigenvalue with zero real part.For a hyperbolic equilibrium point,it is a stable equilibrium point(SEP)if all eigenvalues of its Jacobian have negative real parts;otherwise it is an unstable equilibrium point(UEP).
Let be an hyperbolic EP.Its stable and unstable manifolds, and,are de?ned as follows:
where is the system trajectory starting from at
.Every trajectory in the stable manifold converges to as time goes to positive in?nity,whereas every trajectory in the unstable manifold converges to as time goes to negative in?nity.In particular,for an SEP,its stable manifold ,also called the stability region,is de?ned as
The boundary of stability region is called the stability boundary of and will be denoted by.Characteriza-tions of the stability boundary is a challenging task.If the system admits an energy function,such characterizations can be simpli-?ed.We say a function is an energy function(EF) for the system(1)if the following three conditions are satis?ed: 1)Derivative of the EF along any system trajectory
is non-positive,i.e.,.
2)If is a non-trivial trajectory,i.e.,is not an EP,
then,along the non-trivial trajectory,the set
has measure zero in.
3)If a trajectory has a bounded value of for
implies that the trajectory is also bounded. Note that EFs are not unique and an EF may not be a Lya-punov function since conditions1)–3)must be hold globally. One important feature about EFs is that every trajectory either converges to an EP or becomes unbounded.Thus,the stability boundary can be characterized by the following two theorems: Theorem2.1:(Global Behavior of Trajectories)If a function exists satisfying conditions1)and2)of the EF for(1),every bounded trajectory(1)will converge to one of the EPs. Theorem2.2:(Energy Function and Stability Boundary)If an EF exists for system(1)which has an asymptotically SEP, then the stability boundary is contained in the set,which is the union of stable manifolds of all UEPs on the stability boundary.
One system of interest is the quasi-gradient system[32],[38]:
(2) where is a positive de?nite matrix,is a bounded below function,and all EPs are hyperbolic.It is easy to see
LU AND CHU:CONSENSUS-BASED DROOP CONTROL SYNTHESIS FOR MULTIPLE DICS IN ISOLATED MICRO-GRIDS 2245
that both conditions 1)and 2)of the EF are automatically sat-is?ed [32],[38].From Theorem 2.1,every bounded trajectory (1)will converge to one of the EPs.In addition,since is bounded below,every trajectory is bounded and condition 3)is also satis?ed.is indeed the EF ([32],Proposition 1).This implies that every trajectory is bounded and converges to one of the EPs.In other words,system (2)is completely stable and the entire state space of (2)is composed of the closure of stability regions for each SEP of the system [32].Later,we will use this property to study the stability of closed-loop droop controlled micro-grids.
B.Structure-Preserving Models
The accuracy of micro-grid stability assessment highly depends on the model precision of underlying power grid.Al-though comprehensive dynamical models of micro-grids have been investigated in [39]–[41],from our intensive numerical studies,it can be concluded that the variations in amplitude and/or phase of phasor variables in micro-grids are slow enough in comparison with fast transient dynamics of power electronics.The pseudo steady-state analysis is suf?cient for modeling and analysis for micro-grid droop-control problems.In order to preserve the identity of all grid components,in-cluding DICs,loads,and lines,and provide more physical interpretations among them,we will use the structure-pre-serving models to depict dynamical interactions among various components in micro-grids [42].
Structure-preserving models are usually described by the fol-lowing differential and algebraic equations (DAE)[43]–[46]:
(3a)(3b)
Here
is the state variable while is algebraic variable.Differential equations describe DICs and/or load dynamics while algebraic equations express power ?ow equations at each bus.One drawback of the above DAE formula-tion is that an un-smooth jump behavior will occur once the trajectory reaches the singular surface de?ned by
.These
jump behaviors are due to an incomplete mathematical model of DAE formulation.
Instead of explicitly solving algebraic constraints analyt-ically,one approach to circumvent the singular surface in DAE system is the singular perturbation approach [47].This approach treats the algebraic equation (3b)as a limit of the following fast dynamics:
(4)
where approaches .Thus,for the DAE system (3),we will de?ne an associated boundary-layer equation (BLE)
(5a)(5b)
Since the vector ?eld of (5)is globally well-de?ned,the use of BLE will simplify the complicated analysis associated with the DAE formulation of structure-preserving models.
Fig.1.DICs in a micro-grid.Bus
are power sources with DICs and
Bus
are load buses.C.Droop Control by EF Approach
Dynamical scenarios of droop control for the isolated micro-grid will be proceeded by the following stages:
?Initial Stage :It is assumed that the micro-grid is operated at an acceptable SEP of the pre-stage system.This SEP,obtained from power ?ow solutions,will be the initial point of the droop-control stage.
?Droop-Control Stage :At time ,due to generation/load patterns change,the initial power ?ow will be mismatched.The micro-grid moves to this droop-control stage .The system trajectory will be governed by the closed-loop system with droop control actions.
In terms of nonlinear system theory,this task attempts to de-termine whether the initial point of droop-control stage is lo-cated inside the stability region of an acceptable SEP of the system under proper droop control actions.In order to apply the EF approach to this task,empirically it is assumed that the SEP of initial stage and the SEP of droop-control stage are suf-?ciently close to each other.Thus,the purpose of droop control is to enlarge the stability region of the SEP associated with the droop-control stage such that the SEP of initial stage lies inside the stability region of droop-control stage.Based on this intu-itive thought,more comprehensive droop control methods will be studied in this paper.
III.M ICRO -G RID D ROOP C ONTROL IN S TRUCTURE -P RESERVING M ODELS
For micro-grid droop control problems,we consider a net-work with buses as shown in Fig.1.Buses are power sources embedded with DICs which admit droop controllers.Buses are load buses without droop controllers.Let the bus voltage magnitude and the bus angle be represented by and ,respectively.The column vectors containing voltage magnitudes and bus angles of all buses are then de?ned as
and ,respectively.and are active and
reactive power injections in each DIC bus.and are nom-inal active and reactive power ratings of .and
are load demands in each load bus.The main objective of au-tonomous power sharing in micro-grids is to force all DICs share the overall loads according to their nominal ratings such that
(6a)(6b)
at the ?nal desired steady-state equilibrium point.
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A.Model Descriptions
Dynamical model descriptions of the micro-grid described by the structure-preserving model are stated as follows:
1)Active and Reactive Power Injections at Each Bus:Let all line admittances be represented by,where and being the conductance and susceptance of each trans-mission line between bus and bus,respectively.The active and reactive power injections at each bus can be expressed as
(7a)
(7b) where is the phase angle difference between bus and.
2)Power Converters:Since fast dynamical responses of cur-rent control loops and PWM generations inside the power con-verter are neglected[8],each DIC can be represented as a con-trollable AC voltage source which is governed by a droop con-troller.Under the steady-state,the active power output and reactive power output of each DIC must satisfy the following power?ow equations.For
(8a)
(8b) 3)Loads:Since the structure-preserving models are adopted, more realistic load models can be considered to capture more realistic load behaviors in micro-grids[40].In DAE formula-tion,algebraic equations(3b)correspond to active and reactive power?ow equation at each bus.That is,for
(9a)
(9b)
In recent measurement studies,it can been concluded that the active power load is relatively insensitive to change in voltage magnitude while the reactive power load is relatively insensitive to change in the phase angle[44]–[46].Thus,the active load de-mand can be assumed to be a constant plus an amount propor-tional to the instantaneous frequency.Also,the reactive load demand can be considered to be a function of the bus voltage magnitude plus an amount proportional to the bus voltage devi-ation.These observations motivate us to use the BLE to simplify the DAE formulation in structure-preserving models.Under this framework,loads are represented by the following BLE[44], [48],[49]:for
(10a)
(10b)
Here and are suf?ciently small positive numbers which represent real power load dependences on the bus fre-quency and reactive power
load dependences on the time deriva-tive of voltage magnitude,respectively.Fig.2.Operation principles of conventional-and-droop.
B.Equilibrium Analysis
Static behaviors of the micro-grid depicted by(8)and(10) can be interpreted by solving the power?ow equations.De-pending on network topology and loading conditions,the SEP of(12)may not either exist nor be unique[34],[50],[51].The DIC rating also limits the extent to which the droop is appli-cable.For simplicity,it is assumed that all DICs are operated within their limits.
Since these EPs have a translational symmetry in angle vari-ables,it is common to measure all angle variables relative to an arbitrarily selected swing bus.Thus,if we specify bus1as the swing bus,translational symmetry implies that EPs of(8) and(10)are independent of.By dropping the?rst equations, power?ow equations can be written in reduced form.In order to simplify our analysis,the following assumption is made: Assumption3.1:The SEP of power?ow equations described by(8)and(10)(modulo the translational symmetry)exists and all EPs in reduced form are hyperbolic.
For practical power grids,this assumption is not very rigorous since suf?cient conditions for the existence of SEP of(8)and
(10)have been investigated in[42]and[52].
C.Conventional Droop Control
Depending on line impedances of power grids,conventional droop control methods can be applied to the following three classes of micro-grids:
1)-and-Droop Control for Inductive Lines:If all line impedances are predominantly inductive,,by linearizing power?ow equations(8)over small angle
tions and using the fact that and, the approximations can
(11) Thus,the active power depends on angular deviations and the reactive power depends on the voltage deviations .These dependences suggest the conventional-and-droop control as follows[6]:
(12a)
(12b) where and are the frequency of the th DIC and the nom-inal frequency set-point for-droop control of the isolated grid,respectively.is frequency vari-ation of the th DIC.and are droop coef?cients.One may also observe that the-droop control well mimics the operation of synchronous generators with zero machine inertia. The droop relation between two DICs can be depicted as Fig.2, which suggests proportional power sharing stated as(6).
LU AND CHU:CONSENSUS-BASED DROOP CONTROL SYNTHESIS FOR MULTIPLE DICS IN ISOLATED MICRO-GRIDS2247 2)-and-Droop Control for Resistive Networks:If
all line impedances are predominantly resistive,power?ow
equations(8)will become
(13a)
(13b) By linearizing the above power?ow equations over the small bus angle deviations,the following approximations can be obtained:
(14) Thus,and dependences are evident and they can be utilized for droop control as follows:
(15a)
(15b) 3)Droop Control for Lines With Uniform Ratio:To co-herent the above two droop control methods in the same frame-work,we will consider a class of power grids in which all trans-mission line impedances are modeled by the following assump-tion:
Assumption3.2:All the transmission line impedances
are modeled with the uniform ratio
(16) where and being the resistance and reactance of each transmission line between bus and bus,respectively.
This class of power grid models is of particular interest since the above two droop control methods for either predominately inductive grids or predominately resistive grids,are special cases of this class of power grid models.As suggested in[53], [54],by proper algebraic manipulations of active power and reactive power injections at each bus described by(7),we have
(17a)
(17b) One important implications of the above formulation is that by introducing an equivalent pure reactance network,(17a) and(17b)can be treated as modi?ed power?ow equations with equivalent power injections and
[54].Now the BLE formulation of (8)and(10)can be re-written as the following form:For
(18a)
(18b) The conventional-and-droop control then becomes
(19a)
(19b) Note that similar formulations have been applied for micro-grid with two DICS and two loads[6],where equivalent power injec-tions are utilized to arrange droop characteristics of DICs.Ex-tensions to power grids with multiple DICs and multiple loads are considered in this current work.
IV.R ECENT D ROOP-C ONTROL M ETHODS Although the conventional-droop control provides sat-isfactory results,there exists some disadvantages of the con-ventional-droop control.First,the performance of reactive power sharing under non-uniform output impedances of paral-leled DICs may be deteriorated due to its dependence on output line impedances[5],[6],[8].Secondly,if all line impedances are lossy,the pure--droop relation will no longer hold.In this section,we will study a new droop control method to pro-vide more accurate power sharing.In addition,the stability anal-ysis of the nonlinear closed-loop system will be explored by the EF approach.
A.-and-Droop Control
-droop control aims to improve the reactive power sharing of the conventional-droop control for inductive networks that deteriorated due to its dependence on the line impedances.The idea of the proposed method is to utilize dynamical variables rather than static variables for better reactive power sharing.In the meantime,the task of restora-tions can be achieved by appending as the voltage restoration mechanism which keeps under steady-state conditions. Speci?cally,the-and-droop control for autonomous power sharing operations of multiple DICs can be described in the following way:
(20a)
(20b)
(20c) where is the time derivative of the th DIC's voltage.is the time derivative of the nominal voltage magnitude and is thus identically zero.Equation(20c)describes the additional restoration mechanism to maintain the voltage pro?le to the nominal voltage level.The restoration rate is de-termined by the restoration coef?cient.In comparison with the conventional-and-droop control(12),one extra variable is introduced in(20b)to enhance the reactive power sharing by the control action generated by the time derivative of bus voltage deviation.Detailed small signal stability analyses have already been conducted in[8].
2248IEEE TRANSACTIONS ON POWER SYSTEMS,VOL.30,NO.5,SEPTEMBER2015
When the steady-state is reached,the closed-loop trajectory of(20)will approach one of the power?ow solutions.For sim-plicity,it is assumed that the power?ow solution of the droop-control stage exists.Let the set of constant de-note the corresponding SEP,where
denotes the column vector with all entries equal to1and denotes the synchronized fre-quency of the network.Then for
(21a)
(21b)
(21c) By summing(21a)and(21b)for all buses respectively and de?ning and,we have
(22a)
(22b) where represents the average angle variable de?ned by
(23) This collective angle variable is similar to the center-of-angle (COA)variable used in power system stability analysis[52], [42].and
represent the average frequency and the average derivative of the voltage phasor among all buses.If we represent(20a)in the COA reference frame via the transformation de?ned by
(24) and consider the fact that only angle variables are inde-pendent since
(25) which suggests that the state is only the linear combination of all other angles.Dynamics of-droop control then become
(26a)
(26b) where.Note that is zero under the steady-state.If is larger than any individual ,the dynamical behavior of the average angle variables can be neglected.This means that the coherent instability will not be considered[55].Thus the following assumption is made: Assumption4.1:Under the condition for all, the dynamical behavior of can be neglected.
The above assumption precludes the possibility for coherent instability.However,such phenomenon are seldom observed in real power grid applications.Thus,this assumption is still valid for generic micro-grid con?gurations.B.Stability Analysis
Since the bus voltage magnitude,by following the EF construction for network-preserving power system models [44],[48],one may de?ne new variables by
(27) By substituting(27)into(20b)and(20c),the set of new equa-tions which describe the closed-loop dynamics of the combined -and-droop control can be re-written as follows:
1)For DIC buses,:
(28a)
(28b)
(28c) where.
2)For load buses,:
(29a)
(29b) The state variable of each bus is represented by
and
.The state variables of the overall system are
,which suggest that the total number of states is.
Now we are in the position to?nd analytical expressions of the corresponding EF.This EF indeed has two components:1) is inherent from the power grid con?gurations without considering voltage restoration mechanism,and2)is de-rived from the voltage restoration mechanism.The term
can be derived from the law of energy conservations at each bus [53],[54],it will remain to be a constant for any perturbed tra-jectory.Speci?cally,the total complex energy interacted with the power grid can be de?ned by the complex line integral of bus current injections and branch currents which starts from the current SEP and moves along the path,we have
(30) where and are the current injections at generation and load buses,respectively.is a complex constant which is inde-pendent of the integration path.If all line impedances satisfy As-sumption3.2,power?ow equations will be described by(18a)
LU AND CHU:CONSENSUS-BASED DROOP CONTROL SYNTHESIS FOR MULTIPLE DICS IN ISOLATED MICRO-GRIDS2249
and(18b).By manipulating real and imaginary parts of
can be constructed as follows[56]:
(31) Although remains a real constant along any path,it can be expressed as the sum of three functions with respect to state variable:
(32) where
(33a)
(33b)
(33c) Each term of has the following physical interpretations:
1)is the total potential energy stored on lines.
2)is the total equivalent active potential energy in-
jected and absorbed by generation and load buses,respec-tively.
3)is the total equivalent reactive potential energy in-
jected and absorbed by generation and load buses,respec-tively.
The second component,which comes from voltage restoration mechanisms,is de?ned by
(34)
Thus,the composite EF of above closed-loop system can be described by
(35) In terms of partial derivatives of,the closed-loop system(28)can be written by the following compact represen-tation:
1)For DIC buses
(36)
where
(37)
2)For load buses
(38)
where
(39) Detailed derivations of(37)and(39)will be shown in Appendix A.If the overall system can be rearranged in the order described by,(36)and(38)can be written as the compact form
(40)
where
Worthy to mention,and describe linear combinations of evoked by,and they will not affect the diagonal properties of and.Obviously,matrix is positive de?nite while is positive semi-def-inite with one zero-eigenvalue.In particular,eigenvector anal-ysis shown in Appendix A suggests that this zero-eigenvalue does not lead to trivial eigenvector.However,positive semi-def-initeness of still implies possibility of multiple SEPs of (40).(40)is not the standard quasi-gradient system and
will not be the proper EF for(40)since condition2)of the EF may not be satis?ed.
Fortunately,as shown later in Section V,this defect can be corrected if the consensus-based droop control is enabled.The closed-loop system can be written as quasi-gradient system and condition2)of the EF will be satis?ed under the consensus-based droop control scheme.
C.Droop With Both and Restorations
One drawback of the above--droop controller is that it lacks the mechanism for frequency restorations.This re-sults in degrading power quality under varying load demands in micro-grids.It may also lead to inaccurate real power sharing under heavy load in lossy networks.Similar to voltage restora-tion mechanism mentioned earlier,an additional term related
2250IEEE TRANSACTIONS ON POWER SYSTEMS,VOL.30,NO.5,SEPTEMBER2015
to frequency restoration will be appended in real power control
of(20).The dynamics of will be governed by the frequency deviation.Now(20)will be modi?ed as follows:
(42a)
(42b) In this case,an extra term de?ned by
(43) should be included in the overall EF.Under this framework,the composite EF is de?ned by
(44) where
and.Now the dimen-sion of is.It is easy to verify that(42)can also be reformulated by the following compact form.For
(45)
(46) The eigenvector analysis in Appendix B suggests that matrix is positive semi-de?nite,and the zero eigenvectors are not trivial.If we arrange the overall closed-loop system in the order of,it still can be written as
(47) Again,and representing the linear com-
binations of do not affect the diagonal characteris-tics of and.Since is positive semi-de?nite which may leads to multiple SEPs,(47)is not the standard quasi-gra-dient system and will not be the EF for(47).Similar to the previous case,this defect can also be corrected by the con-sensus-based droop control discussed in Section V.
As mentioned earlier,the droop relation becomes predom-inately--if line impedances are pure resistive.The droop controllers shown in(42)will be modi?ed accordingly.
V.C ONSENSUS-B ASED D ROOP C ONTROL Although the systems described by(40)and(47)are stable, incorrect reactive power sharing under non-uniform line im-pedances between paralleled DICs were still observed[8].One reason for such inaccuracy comes from the existence of zero-eigenvalues for and which implies the existence of pos-sible multiple power?ow solutions.The accurate power sharing will not proceed under lossy networks since the pure-and -droop control will no longer hold.
The consensus-based droop control aims to overcome this dif?culty.The idea of the consensus-based-droop control was proposed by[27].In this paper,we will extend their work to consider the consensus-based-and-droop control si-multaneously.
A.Graph Theory and Consensus Algorithm
A graph is a?nite non-empty set of ele-ments named vertices,along with a set of two element sub-sets of named edges.A graph is said to be simple whenever it is1)unweighted;2)with undirected edges;3)without graph loop;4)without multi-edge[57].Due to the nature of power networks,it is suf?cient to consider them as simple graphs.The adjacency matrix of a simple graph,denoted,is the symmetric matrix with rows and columns both indexed in order of,and with entries
(48) The degree matrix of graph,denoted,is the diagonal matrix with the vertex degrees along its diagonal,where the degree of vertex stands for the number of incident edges.The Laplacian of a graph is then de?ned as
(49) where is the entry of.
The diffusion,which is usually used to described the process of gas moving in accordance with the distribution of its density, can also be studied to portray the spread of information in a network.Suppose the?ow between any two vertices and
is managed as,where is a constant called diffusion constant.The varying rate of can be found as
(50) The above dynamics can be expressed in the compact form
(51)
LU AND CHU:CONSENSUS-BASED DROOP CONTROL SYNTHESIS FOR MULTIPLE DICS IN ISOLATED MICRO-GRIDS2251
All vertices of the graph will globally asymptotically reach an average-consensus
(52) which is promised by the average-consensus theorem[15].The function stands for the average of the input vector.Note that the convergence rate can be adjusted by varying the diffu-sion constant.
B.Operation Principles
Now we are in a position to develop the consensus-based --droop control.By introducing the Laplacian matrix of the communication network among all DICs,the closed-loop of consensus-based--droop control can be constructed as follows:
(53a)
(53b)
(53c)
(53d) Notice that for(53a)and for (53b)to(53d).In the above formulation,is the entry of the graph Laplacian of interconnected DICs.Since the off-diagonal entries of indicate the physical connectivity between vertices of the network,the communication protocol needs to be established among physical neighbors of each DIC only.Note that in--droop control,the extra control terms and in(42a)and(42b)is feedback by the local signal and only.However,in consensus-based droop control, and from neighboring buses will contribute the feedback sig-nals and eventually reach their average values.Since the value will affect the convergence rate,will be adjusted to?t the numerical order of the state variables and.In recent work, [28]suggested that the value of can be set by the global in-formation discovery algorithm[15].
The consensus-based droop control method requires com-munication interfaces,practical consideration of the employed communication technology should be considered.The perfor-mance of different levels of web-based communication have been examined in[58],they then suggested a trade-off between power sharing accuracy and required bandwidth of commu-nication,which leads to a more economical development of DG-based micro-grid.In[59],several industrial standards of communication technologies for power sharing have been studied.A wireless communication-based control method, which improves the system reliability and operation accuracy, was then proposed and examined against different disturbances in a micro-grid.Since the consensus-based control proposed in this paper requires only low-bandwidth communication between interconnected DICs,implementations over wireless networks or power-line communication are feasible,which increases the reliability of this secondary control and ensure plug-and-play ability among DICs.
It is worthy to pointing out that if the consensus control is inactivated by setting for all,the consensus-based droop control will be reduced to--droop control.All trajectories will still converge to one of the EPs.Thus,the con-sensus-based droop control can be considered as a supplemen-tary control actions from neighboring DICs.This implies that the overall consensus-based droop control algorithm is com-posed of two phases:the primary local--droop con-trol and the supplementary consensus-based droop control.The local--droop control will dominate dynamical behav-iors of the closed-loop system in the early stage.Thus,in the ?rst phase,the frequency restoration and synchronization mech-anism governed by(53a)and(53b)will reach the steady-state soon.The system will move to the consensus-based droop con-trol phase.Under this framework,the initial state of the con-sensus-based droop control under steady-state of(53a)can be represented approximately by
where is de?ned as the completion time of the rather fast fre-quency restoration and the synchronization mechanism.Since is obviously nearly zero,the dynamics of(53b)can be approximately described by the?rst-order consensus algorithm described by(50)as
(54) Following the average-consensus theorem in(52),(54)would drive all to be identical as
(55) which is exactly the average frequency deviation among the DICs.By substituting(55)into(53a),we have
(56) Since is the common setting for each droop controlled DIC,appending this consensus term will drive each DIC to share the real loads proportional to their nominal ratings.Similar conclusions about reactive power can be made by considering(53c)and(53d).Thus,the reactive power sharing can be achieved as(6b).
C.Stability Analysis by EF
The above discussions provide some interpretations of the op-eration of two-phase consensus-based droop control algorithms. Mathematically,stability of the closed-loop dynamics of con-sensus-based droop controller can also be proven by the EF ap-proach.Indeed,(53)can also be reformulated as the following compact form:
(57)
.The rearrangement from to comes from including the DIC network Laplacian.Also,and
2252IEEE TRANSACTIONS ON POWER SYSTEMS,VOL.30,NO.5,SEPTEMBER
2015
Fig.3.Proposed droop controller for individual DIC.
are modi?ed to and,respectively.It is easy to verify that and is full rank.,
where.Gener-ically,the small perturbation on positive semi-de?nite pro-vided by would lead to non-singular.In addition, the closed-loop system damping by the consensus-based droop control will increase since each positive term of will ap-pear on the diagonal of.Additional negative terms will appear on the analytical expression of.Thus,the closed-loop system under the consensus-based droop control will be equipped with extra damping.Now we are in the po-sition to summarize this result:
Theorem5.1:If assumptions(A3.1),(A3.2),and(A4.1) are satis?ed,the micro-grid systems equipped with the pro-posed consensus-based-and-droop controlled DICs is stable.
This consensus-based droop control can also be applied for nearly pure resistive micro-grids by employing--droop control instead of--droop.And similar stability analysis framework depicted above can also be applied.
VI.R EAL-T IME S IMULATION R ESULTS
In order to validate the performance of consensus-based --droop controller,simulations of two6-DIC micro-grids have been conducted by real-time simulators manufactured by OPAL-RT[60].Control block diagrams of the consensus-based--droop controller for individual DIC are shown in Fig.3.Detailed circuit models including PWM dynamics in each DIC,rather than the phasor model,are all considered in the real-time simulation environment.This makes the number of model states counted up to
241
and310
for7-bus and14-bus micro-grids,respectively.Parameters of DICs used in our simulations are listed as follows:?System voltage:Three-phase220V,60Hz.
?DICs:Rated2KV A,2-level PWM converters,switching frequency kHz,output?lter inductor mH, output?lter capacitor F.The?lter is designed based on the cut-off frequency
kHz,which is much faster than operation frequency of the droop controllers.
TABLE I
D ROOP C OEFFICIENTS
Fig.4.7-bus6-DIC micro-grid for Cases I.
?The--droop controls without consensus mecha-nism are also developed for comparison studies.The cor-responding droop coef?cients are listed in Table I.
A.7-Bus Micro-Grid With a Single Load
The7-bus6-DIC micro-grid system shown in Fig.4is?rst developed to validate the stability of consensus-based-
-droop controlled DICs.The micro-grid is actually part of the IEEE-69bus distribution system[33]and only a single load bus is included.The line impedances are adjusted as follows to validate our droop control methods:
?Case I:.The impedance of the micro-grid is lossy where--droop control are deployed. Information about the line impedances and the loads of this system are listed in Table II.The simulation scenario is arranged as varying system loads from light loads to heavy loads .
Simulation results are shown in Fig.6.Due to the highly lossy network impedances,though nominal frequency and voltages are preserved by the restoration mechanism,accurate active and reactive power sharing cannot be achieved by the --droop control.This is then resolved by the proposed consensus-based droop control,which converges to a proper
LU AND CHU:CONSENSUS-BASED DROOP CONTROL SYNTHESIS FOR MULTIPLE DICS IN ISOLATED MICRO-GRIDS 2253
TABLE II
M ICRO -G RID N ETWORK D
ATA
Fig.5.14-bus 6-DIC micro-grid for Cases
II.
Fig.6.Case I:(a)--droop;(b)consensus-based --droop.
equilibrium point just as anticipated by the previous nonlinear stability analysis.Accurate power sharing can be achieved by the proposed droop control methods even under considerably large load disturbances.
B.14-Bus Micro-Grid With Multiple Loads
Now we consider the proposed droop control method applied to 14-bus with multiple load buses as shown in Fig.5.
Again
Fig.7.Case II:(a)--droop;(b)consensus-based --droop.
the system is actually part of the IEEE 69-bus system,with line impedances further adjusted with the uniform ratio:?Case II:,lossy network where --droop deployed.
Multiple load buses are arranged across the network to validate the convergence of consensus-based droop control concluded by nonlinear stability analysis in this paper.And load variations of are applied.The line impedances and load information are listed in Table II.
Simulation results are shown in Fig.7.Similar to results de-picted in the 7-bus micro-grid with a single load,the consensus-based --droop controller can alleviate the effects of non-ideal line impedances and share loads accurately.Furthermore,it can also be observed that the accurate sharing of multiple power consumption cites,which is promised by nonlinear stability anal-ysis,can be achieved by the proposed droop control methods.
2254IEEE TRANSACTIONS ON POWER SYSTEMS,VOL.30,NO.5,SEPTEMBER2015
VII.C ONCLUSION
In this paper,the consensus-based--droop controller
is proposed for autonomous power sharing in micro-grid.In par-
ticular,we have
?applied the theory of consensus control in multi-agent sys-
tems to droop control problems;
?proven the stability of DICs controlled by the proposed
droop controllers by the transient EF approach;
?ensured that the system damping can be indeed improved.
Real-time simulations for a7-bus/6-DIC micro-grid and its multiple load bus extension are then developed on real-time simulator manufactured by OPAL-RT.The consensus-based --droop controller is validated in them with corre-sponding impedance https://www.doczj.com/doc/8d3054851.html,pared with--droop control strategy,the proposed consensus-based droop control obviously alleviate the effects of non-ideal line imped-ances with better dynamical performances.Accurate power sharing is achieved along with restorations of power frequency and terminal voltages of DICs.
Since the EF approach can unify all existing droop control methods in the same framework,extensions of the current work are still possible.For example,additional control strategies for restoring the DC-link voltages and possible energy storage de-vices in distributed generations are possible directions.More-over,since the intermittent renewable sources may cause the DERs reach their output limitations,more complicated control strategies considering the operation boundaries of DERs should be considered.We will investigate these issues in the near future.
A PPENDIX A
C OMPACT F ORMS OF-AND-
D ROOP C ONTROL Employing the term to described from(33a) to(34),(28)can be re-written as follows:
(58a)
(58b)
(58c) where for
Since
,(58)can be expressed in a compact form as(36).In order to simplify the expression of,the following elementary matrix is applied:
(59) By simple algebraic manipulations,matrix is found to be positive semi-de?nite with one zero-eigenvalue and cor-responding zero-eigenvector.If the initial state of (36)is this zero-eigenvector,we have
which implies
(60) Compare with(58a)and(58b),(60)suggests
,which is indeed the EP of(58a)and(58b).Thus,this zero-eigenvalue will not lead to trivial eigenvectors.
A PPENDIX B
C OMPACT F ORM FOR
D ROOP W ITH B OTH AND
R ESTORTATIONS
By applying the elementary matrix to derived from(46),we have
(61)
(62) Equation(62)implies that is positive semi-de?-nite and is singular with two zero-eigenvalues.We can show
LU AND CHU:CONSENSUS-BASED DROOP CONTROL SYNTHESIS FOR MULTIPLE DICS IN ISOLATED MICRO-GRIDS2255
that these zero-eigenvalues do not lead to trivial eigenvec-tors.Let the corresponding eigenvectors take the form of .Compare with(61),it can be seen that
(63) By applying(63)to,we have
(64) which implies
(65) Obviously,the solution of(65)is indeed the EP of(42a)and (42b)by similar manipulations performed in(28a)and(28b).
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Lin-Yu Lu(S'12)was born in Taichung,Taiwan,on
February20,1987.He received the B.S.and M.S.de-
grees in electrical engineering from National Tsing
Hua University,Hsinchu,Taiwan,in2009and2011,
respectively.He is currently pursuing the Ph.D.de-
gree in the Department of Electrical Engineering,Na-
tional Tsing Hua University.
His?elds of research interest include micro-grid
control and related power electronics
applications.
Chia-Chi Chu(M'96)received the B.S.and M.S.
degrees in electrical engineering from National
Taiwan University,Taipei,Taiwan,and the Ph.D.
degree in electrical engineering from Cornell Uni-
versity,Ithaca,NY,USA,in1996.
From1995to1996,he was a member of the tech-
nical staff at Avant!Corporation,Fremont,CA,USA.
From1996to2006,he was a faculty member of Elec-
trical Engineering at Chang Gung University,Tao-
Yuan,Taiwan.Since2006,he has been an Associate
Professor of Electrical Engineering at National Tsing Hua University,Hsin-Chu,Taiwan.He was a visiting scholar at the University of California at Berkeley in1999.His current research interests include power system stability,FACTS,and micro-grid control.
Dr.Chu was the recipient of the Young Author Award of the IEEE Control of Oscillations and Chaos Conference(COC)in1997and the IEEE8th Inter-national Conference on Power Electronics and Drive Systems(PEDS)in2009.
---------------------- 前台规章制度 一、仪容仪表 1. 上班时间需化淡妆，长发须佩戴头花或盘起。 2. 着装必须干净整洁，必须穿工作服上班。 3. 不能留长指甲，不能涂指甲油，不能佩戴夸张的饰品。 4. 保持最佳的精神状态工作。 二、工作纪律 1. 上班时间，不能吃东西、上网看电视，打接与工作无关的电话时间不能过长（特殊情况和家里重大事情除外）。 2. 上班时间不能在前台睡觉、不能串岗、不能拿上班时间会客，不能大声喧哗。 3.上班时间不能无故缺席，离岗时要在登记表做好记录（楼层巡检，吃饭，检查各个会议室等）不得无故闲逛。 三、工作规定 1. 上班期间服务态度好。主动向客人问好、站立服务、耐心的与客人交流，让客人在酒店住的舒适。 2. 员工不能把私人情绪带入工作中，随时随地对客人保持微笑。 3. 不能拿酒店财物私用或带回家（如有发现一律重罚或开除）。 4. 时刻保持前台的清洁。 5. 员工不能徇私舞弊，互相包庇。 6. 当班人员上班，不能迟到早退、不能擅自离岗、不能私自换班（需提前报告领导写好换班条，待领导审批，通过方可换班）、不能无故旷工（特殊情况可向部门领导请示）。 以上规章制度一经核实，发现第一次给予警告，第二次给予罚款，犯多次或屡教不改者，公司有权给予开除处理。 备注：（罚款方式：第一次20元，第二次50元，情况严重者重罚） ---------------------------------------------------------精品文档
---------------------- ---------------------------------------------------------精 品 文档前台工作内容 1. 为客人办理入住登记并请客人签字确认，认付款方式(挂账、现金,)问明付过押金后给客人房卡，并向客人解释房卡内容，在电脑中及时占房，发放早餐卷。 2.住宿登记单上,住几个人写几个人的名字,以便开门。入住时要询问客人住几天,以便刷几天的房卡,收几天的房费。同时,电脑上时间也要与此一致, 以方便楼层。坚持姓氏称呼。 3.阅读交班本，了解上一班未完成事项，及时进行跟进和处理。 4.查看各部门钥匙使用和归还纪录情况，并将钥匙分类放置。 5.核对房态，确保房态正确，清点房卡，所有一致加起来数目和上一班交接相符和。 6.如有客人要求换房，确定已通知客房服务人员和楼层服务人员进行打扫，检查。确认无误，收回房卡，发放新的发卡为客人换房。 7.了解每日会议信息和会议用房数，若会议举办方有任何要求，及时与楼层服务员和客房服务 员联系并跟进。
酒店房卡管理规定 一、房卡类别 1、客房房卡分总控卡、领班卡、楼层卡、客人卡。 2、总控卡由相关管理人员持有。 3、领班卡由各楼层领班持有。 4、楼层卡各楼层员工持有。 5、客人卡由前台员工保管、制作。 注：若领班卡、楼层卡丢失或损坏，应立即上报部门，采取相应的措施（消磁和补办），当班人员要有补办记录，以免酒店遭受损失 二、房卡管理 1、总控卡由总经理、副总经理、前厅部经理、客房部经理、大堂经理持有。 2、领班卡、楼层卡由客房服务中心保管，实行每天签字借用制度。 ⑴领班卡用于查房使用，此卡可以开启所管辖的楼层所有客房房门。 ⑵楼层卡用于服务员打扫卫生使用，按照服务员的工作范围制作。 ⑶调换楼层时要有交接手续。
3、持卡人不得将自己的卡借给其他人员使用，一定发现必将严惩。 4、客人卡的管理制度： ⑴将客房卡交给客人前，前台员工必须确认客人身份； ⑵前台原则上单人房每间只发放一张房卡，双人房根据客人要求可发放两张房卡，并在电脑中注明数量； ⑶客人房卡遗失： 验明客人身份和登记相符→说明规定，向客人收取或从押金中扣除赔偿费→重新制作l张新的房卡给客人→确保前一张房卡作废。 ⑷客人钥匙损坏： A. 验卡→显示房号和客人所报相同，且在期限内→重新制作一张房卡给客人，并与客人说明赔偿费用。 B. 如果卡号不能显示或不能验卡→验明客人身份和登记相符→重新制作1张房卡给客人，并向客人说明赔偿费用。 ⑸客人寄存钥匙： A. 听清客人所报房号，请客人稍等→验卡→显示房号和客人所报一致，取房卡袋填写房号，将房卡插入房卡袋内，放在抽屉内→客人来取时，验明身份后，交还房卡。 B. 如验卡时，房号不能显示，应先验明身份，再进行寄
酒店前台房卡管理规定 SANY GROUP system office room 【SANYUA16H-
前台房卡管理规定 一、房卡类别： 1、客房房卡分总控卡、领班卡、楼层卡、客人卡。 2、总控卡店级领导、客房相关管理人员持有（董事长、总经理、副总经理、客务总监、客房经理） 3、领班卡由各楼层领办持有 4、楼层卡各楼层员工持有 5、客人卡由前台员工制作 注：若领班卡、楼层卡丢失或损坏，应立即上报部门，采取相应的措施（消磁和补办），前台要有补办记录，以免酒店遭受损失 二、客人卡的管理制度： 1、将客房匙交给客人前，前台员工必须确认客人身份； 2、前台原则上单人房每间只发放一条房匙，双人房根据客人要求可发放两条房匙，并在电脑中注明； 3、客人房卡遗失： 验明客人身份和登记相符→说明规定，向客人收取或从押金中扣除赔偿费（30元）→重新制作l把新的钥匙给客人→通知房务中心→使用管理卡到该房间插一次卡（做消磁处理），确保插卡前使用的钥匙作废。 4、客人钥匙损坏： A.验卡→显示房号和客人所报相同，且在期限内→重新制作l把钥匙给客人，并向客人致歉。 B.如果卡号不能显示或不能验卡→验明客人身份和登记相符→重新制作1把钥匙给客人，并向客人致歉。 5、客人寄存钥匙： A.听清客人所报房号，请客人稍等→验卡→显示房号和客人所报一致，取房卡填写房号，钥匙插入新房卡，放在寄存抽屉内→客人来取时，验明身份后，交还钥匙，将写房号的房卡撕毁。 B.如验卡时，房号不能显示，应先验明身份，重新制作钥匙，再进行寄存。 C.如客人寄存时嘱咐他人来取→填写留言单，请客人签字确认→钥匙、留言单放在房卡中存放于收银抽屉内→领取时验明身份→留言单保留在客帐内直至客人退房。 6、客人退房时，前台员工应提醒客人交还房匙→如客人出示的钥匙没有房卡或押金单证明其房号，必须验卡验证无误后，方可通知客房服务员查房并办理退房手续。 7、退房时，客人将钥匙留在房间：客房服务员查完房交到前台。凡有折痕、断裂、明显污迹、坏的钥匙，交前台主管保管。
家装用尺寸一览表 Revised by Hanlin on 10 January 2021
家装用尺寸一览表 ▌标准入户门洞0.9m*2m， ▌房间门洞0.9m*2m， ▌厨房门洞0.8m*2m， ▌卫生间门洞0.7m*2m ▌客厅：长沙发：240*90*75cm长方形茶几：130*70*45cm电视柜：200*50*180cm电视离沙发：3m电视高度与电视柜高差：40到120cm走道宽度：100至120cm ▌厨房：橱柜操作台：台面高80cm左右面积90*46（最小20最大60）cm吊柜：离台面60cm左右高度在145cm到150cm餐桌：餐桌高：750—790mm。餐椅高；450—500mm。圆桌直径：二人500mm．二人800mm，四人900mm，五人1100mm，六人1100-1250mm，八人1300mm，十人l500mm，十二人1800mm。方餐桌尺寸：二人700×850(mm)，四人1350×850(mm)，八人2250×850(mm) ▌卫生间：浴缸长度：一般有三种1220、1520、1680mm；宽：720mm，高：450mm。坐便：750×350(mm)。冲洗器：690×350(mm)。盟洗盆：550×410(mm)。淋浴器高：2100mm。化妆台：长：1350mm；宽450mm。 ▌卧室：标准双人床尺寸：150*190、150*200厘米，被套的尺寸应配180*215和200*230之间的。加大双人床尺寸：180*200厘米，被套一般为200*230或220*240。床头柜宽：400毫米-600毫米，深：350毫米-450毫米高：500毫米-700毫米。衣柜：柜门尺寸，单
酒店前台房卡管理 一、房卡类别及制卡权限： 1、客房房卡分总卡、领班卡、楼层卡、客人卡 2、总卡为客房相关管理人员持有（董事长、总经理、副总经理、客务总监、客 房经理、前厅经理）由前厅经理制作 3、领班卡由各楼层领办持有由大堂副理或前厅经理制作 4、楼层卡各楼层员工持有由大堂副理制作 5、客人卡由前台员工制作 二、客人卡的管理制度： 1、将房卡交给客人前，前台员工必须确认客人身份； 2、前台原则上单人房每间只发放一张房卡，双人房根据客人要求可发放两张房 卡，并在电脑中注明； 3、客人房卡遗失： 验明客人身份和登记相符→说明规定，向客人收取或从押金中扣除赔偿费（50元）→重新制作一张新的房卡给客人→通知房务中心→使用管理卡到该房间插一次卡（做消磁处理），确保插卡前使用的房卡作废。 4、客人房卡损坏： 1)验卡→显示房号和客人所报相同，且在期限内→重新制作一张房卡给客人， 并向客人致歉。 2)如果房卡号不能显示或不能验卡→验明客人身份和登记相符→重新制作一 张房卡给客人，并向客人致歉。
5、客人寄存房卡： 1)听清客人所报房号，请客人稍等→验卡→显示房号和客人所报一致，取 房卡套填写房号，房卡插入房卡套，放在寄存抽屉内→客人来取时，验明身份后，交还房卡，将写房号的房卡套撕毁。 2)如验卡时，房号不能显示，应先验明身份，重新制作房卡，再进行寄存。 3)如客人寄存时嘱咐他人来取→填写留言单，请客人签字确认→房卡、留 言单放在房卡中存放于收银抽屉内→领取时验明身份→留言单保留在客帐内直至客人退房。 6、客人退房时，前台员工应提醒客人交还房卡→如客人出示的房卡没有房卡 或押金单证明其房号，必须验卡验证无误后，方可通知客房服务员查房并办理退房手续。 7、退房时，客人将房卡留在房间：客房服务员查完房交到前台。凡有折痕、断 裂、明显污迹、坏的房卡，交前台主管保管并做记录。 8、未经登记客人许可，不得为任何来访者开启客人房间或发卡给来访者； 9、任何服务员如发现房卡遗留于公共场所，应立即交当值主管，送回前台接待 处处理； 10、客房服务员不得对客人以错放房卡在房间内为由，随便开房门让客人进入， 应即时打电话到前台接待处核实客人身份，如有任何疑问，应请客人到前台接待处办理补卡手续。 11、前台服务员每班交接时，必须核对客人房卡数量。发现任何缺失必须上报 并在交接本上作记录。 12、所有房卡上不能贴房号
家具设计的基本尺寸（单位：cm） 衣橱：深度：一般60~65；推拉门：70，衣橱门宽度：40~65 推拉门：75~150，高度：190~240 矮柜：深度：35~45，柜门宽度：30-60 电视柜：深度：45-60，高度：60-70 单人床：宽度：90，105，120；长度：180，186，200，210 双人床：宽度：135，150，180；长度180，186，200，210 圆床：直径：186，212.5，242.4（常用） 室内门：宽度：80-95，医院120；高度：190，200，210，220，240 厕所、厨房门：宽度：80，90；高度：190，200，210 窗帘盒：高度：12-18；深度：单层布12；双层布16-18（实际尺寸） 沙发：单人式：长度：80-95，深度：85-90；坐垫高：35-42；背高：70-90 双人式：长度：126-150；深度：80-90 三人式：长度：175-196；深度：80-90 四人式：长度：232-252；深度80-90 茶几：小型，长方形：长度60-75，宽度45-60，高度38-50（38最佳） 中型，长方形：长度120-135；宽度38-50或者60-75 正方形：长度75-90，高度43-50 大型，长方形：长度150-180，宽度60-80，高度33-42（33最佳） 圆形：直径75，90，105，120；高度：33-42 方形：宽度90，105，120，135，150；高度33-42 书桌：固定式：深度45-70（60最佳），高度75 活动式：深度65-80，高度75-78 书桌下缘离地至少58；长度：最少90（150-180最佳） 餐桌：高度75-78（一般），西式高度68-72，一般方桌宽度120，90，75；长方桌宽度80，90，105，120；长度150，165，180，210，240 圆桌：直径90，120，135，150，180 书架：深度25-40（每一格），长度：60-120；下大上小型下方深度35-45，高度80-90活动未及顶高柜：深度45，高度180-200 木隔间墙厚：6-10；内角材排距：长度（45-60）*90
星级酒店房卡管理制度4 一、房卡类别： 1、客房房卡分总控卡、领班卡、楼层卡、客人卡。 2、总控卡店级领导、客房相关管理人员持有(董事长、总经理、副总经理、客务总监、客房经理) 3、领班卡由各楼层领办持有 4、楼层卡各楼层员工持有 5、客人卡由前台员工制作 注：若领班卡、楼层卡丢失或损坏，应立即上报部门，采取相应的措施(消磁和补办)，前台要有补办记录，以免酒店遭受损失 二、客人卡的管理制度： 1、将客房匙交给客人前，前台员工必须确认客人身份; 2、前台原则上单人房每间只发放一条房匙，双人房根据客人要求可发放两条房匙，并在电脑中注明; 3、客人房卡遗失： 验明客人身份和登记相符→说明规定，向客人收取或从押金中扣除赔偿费(30元)→重新制作l把新的钥匙给客人→通知房务 中心→使用管理卡到该房间插一次卡(做消磁处理)，确保插
卡前使用的钥匙作废。 4、客人钥匙损坏： A.验卡→显示房号和客人所报相同，且在期限内→重新制作l把钥匙给客人，并向客人致歉。 B.如果卡号不能显示或不能验卡→验明客人身份和登记相符→重新制作1把钥匙给客人，并向客人致歉。 5、客人寄存钥匙： A.听清客人所报房号，请客人稍等→验卡→显示房号和客人所报一致，取房卡填写房号，钥匙插入新房卡，放在寄存抽屉内→客人来取时，验明身份后，交还钥匙，将写房号的房卡撕毁。 B.如验卡时，房号不能显示，应先验明身份，重新制作钥匙，再进行寄存。 C.如客人寄存时嘱咐他人来鳃填写留言单，请客人签字确认→钥匙、留言单放在房卡中存放于收银抽屉内→领取时验明身份→留言单保留在客帐内直至客人退房。 6、客人退房时，前台员工应提醒客人交还房匙→如客人出示的钥匙没有房卡或押金单证明其房号，必须验卡验证无误后，方可通知客房服务员查房并办理退房手续。 7、退房时，客人将钥匙留在房间：客房服务员查完房交到前台。凡有折痕、断裂、明显污迹、坏的钥匙，交前台主管保管。 8、未经登记客人许可，不得为任何来访者开启客人房间或
家具设计的基本尺寸（单位：厘米） 衣橱：深度：一般60~65；推拉门：70，衣橱门宽度：40~65 推拉门：75~150，高度：190~240 矮柜：?深度：35~45，柜门宽度：30-60 电视柜：深度：45-60，高度：60-70 单人床：宽度：90，105，120；长度：180，186，200，210 双人床：宽度：135，150，180；长度180，186，200，210 圆床：?直径：186，，（常用） 室内门：宽度：80-95，医院120；高度：190，200，210，220，240 厕所、厨房门：宽度：80，90；高度：190，200，210 窗帘盒：高度：12-18；深度：单层布12；双层布16-18（实际尺寸） 沙发：单人式：长度：80-95，深度：85-90；坐垫高：35-42；背高：70-90双人式：长度：126-150；深度：80-90 三人式：长度：175-196；深度：80-90 四人式：长度：232-252；深度80-90 茶几：小型，长方形：长度60-75，宽度45-60，高度38-50（38最佳） 中型，长方形：长度120-135；宽度38-50或者60-75 正方形：?长度75-90，高度43-50 大型，长方形：长度150-180，宽度60-80，高度33-42（33最佳）
圆形：直径75，90，105，120；高度：33-42 方形：宽度90，105，120，135，150；高度33-42 书桌：固定式：深度45-70（60最佳），高度75 活动式：深度65-80，高度75-78 书桌下缘离地至少58；长度：最少90（150-180最佳） 餐桌：高度75-78（一般），西式高度68-72，一般方桌宽度120，90，75； 长方桌宽度80，90，105，120；长度150，165，180，210，240 圆桌：直径90，120，135，150，180 书架：深度25-40（每一格），长度：60-120；下大上小型下方深度35-45，高度80-90 活动未及顶高柜：深度45，高度180-200 木隔间墙厚：6-10；内角材排距：长度（45-60）*90 桌类家具高度尺寸：７００ｍｍ、７２０ｍｍ、７４０ｍｍ、７６０ｍｍ四个规格； 椅凳类家具的座面高度：４００ｍｍ、４２０ｍｍ、４４０ｍｍ三个规格。 桌椅高度差应控制在２８０至３２０ｍｍ范围内。
提供全方位装修指南，装修设计知识、丰富设计案例！ 家装各种最佳尺寸标准大全! 家装最实际的规格尺寸 标准红砖24*11.5*53； 标准入户门洞0.9米*2米， 房间门洞0.9米*2米， 厨房门洞0.8米*2米， 卫生间门洞0.7米*2米， 标准水泥50kg/袋。 厨房 1.吊柜和操作台之间的距离应该是多少？ 60厘米。 从操作台到吊柜的底部，您应该确保这个距离。这样，在您可以方便烹饪的同时，还可以在吊柜里放一些小型家用电器。 2.在厨房两面相对的墙边都摆放各种家具和电器的情况下，中间应该留多大的距离才不会影响在厨房里做家务？ 120厘米。 为了能方便地打开两边家具的柜门，就一定要保证至少留出这样的距离。 150厘米。 这样的距离就可以保证在两边柜门都打开的情况下，中间再站一个人。 3.要想舒服地坐在早餐桌的周围，凳子的合适高度应该是多少？ 80厘米。 对于一张高110厘米的早餐桌来说，这是摆在它周围凳子的理想高度。因为在桌面和凳子之间还需要30厘米的空间来容下双腿。 4.吊柜应该装在多高的地方？ 145至150厘米。
提供全方位装修指南，装修设计知识、丰富设计案例！ 餐厅 1. 一个供六个人使用的餐桌有多大？ 2. 120厘米。 这是对圆形餐桌的直径要求。 140*70厘米。 这是对长方形和椭圆形捉制的尺寸要求。 2.餐桌离墙应该有多远？ 80厘米。 这个距离是包括把椅子拉出来，以及能使就餐的人方便活动的最小距离。 3.一张以对角线对墙的正方形桌子所占的面积要有多大？ 180*180平方厘米。 这是一张边长90厘米，桌角离墙面最近距离为40厘米的正方形桌子所占的最小面积。 4.桌子的标准高度应是多少？ 72厘米。 这是桌子的中等高度，而椅子是通常高度为45厘米。 5.一张供六个人使用的桌子摆起居室里要占多少面积？ 300*300厘米。 需要为直径120厘米的桌子留出空地，同时还要为在桌子四周就餐的人留出活动空间。这个方案适合于那种大客厅，面积至少达到600*350厘米。 6.吊灯和桌面之间最合适的距离应该是多少？ 70厘米。 这是能使桌面得到完整的、均匀照射的理想距离。 卫生间 1．卫生间里的用具要占多大地方？ 马桶所占的一般面积： 37厘米×60厘米。
客房部房卡管理制度及开门程序 房卡管理制度 1、作为客房部的任何一员，如将总卡或是楼层卡丢失，就等于丢掉自己的这份工作，后果是不堪设想的，因为这关系到酒店和客人的财产安全和人生安全问题； 2、所有持卡人都应做到卡不离人，不可将卡乱扔乱放，更不可 将卡随便给部门以外的人去开房门； 3、每天上下班或吃饭的时候，都应有交接卡的程序，做好交接 的登记； 4、不可将卡带离工作岗位，用餐或下班时应将卡交还房务中心保管； 5、每个持卡人都应爱护房卡，正确使用房卡。 敲门开门程序 1、客房部任何持卡人都应养成，不管是任何房态（也就是说： 不管是空房、住人房、锁房还是维修房等等”）都应养成敲门报服务员”的好习惯； 2、在开房门前首先要时刻了解所要开门的房间状态（即:房态），一般除住人房而外，我们只需敲一次房门报服务员”即可，而对 住客房来讲就不能简单化，不管此时房间是否有客或是无客，都应先按门铃三下或再敲三次房门，然后报：服务员”同时耳朵 要时刻关注房间有无动静（也就是说：是否听到有客人回应？”； 3、不可不敲门直接就拿房卡开门，或者是边敲门边插房卡开门，
还有任何人都不能抱有：我以为房间没有客人”的这种想法，而 直接插卡开门的话，将会酿成大错，这些可都是开门的大忌； 4、开门时要注意房卡芯片的朝向，同时要懂得识别电脑锁信号灯所表示的意思，电脑锁信号灯一般有以下四种表示意义： A、房卡芯片朝向正确和设置房号和门牌号对得上，插入房卡电脑锁会亮绿灯，你会听到嘟”一声，此时立即拔出房卡，此时又会听到电脑锁内弹簧回弹的声音，这时房门就可以打开了； B、房卡所设置的房号与门牌号对不上（也就是说：客人如果走错房间”，或者是房卡超时和插卡不到位，此时电脑锁会闪三下黄灯，房门是打不开的； C、任何房卡插反了，电脑锁都会亮红灯，抽出房卡红灯立即熄 灭，此时房门是打不开的； D如果房间里面打上防盗栓的话，此时用总卡、楼层卡、宾客卡开门，电脑锁都会先亮黄灯，再亮红灯，并且会有嘟”一声鸣响； E、不管你怎么插卡，电脑锁都不会亮灯的话，表示电脑锁没有电了，就要采取措施更换电池，方可用卡开门。 5、客房部任何持卡人都不能随便用自己的卡去帮客人开门，必 须确认客人身份无误后，方可用自己的卡帮客人开门，一般客人开不了门并要求帮其开门有以下几种情况： A、客人有卡，没欢迎卡，走错房间； B、客人有卡，有/无欢迎卡，但客人不会开；
【精华】室内装修，必须预留的最佳尺寸标准大全 2014-08-29筑龙房地产筑龙房地产 阅读引语 强烈推荐大家存的一份装修预留尺寸标准！！非常实用！！ 现在新房子的设计一般都会交给专门的设计师来做，但哪怕是专业设计师制作的设计图稿，没有实地接触的设计师可能还会存在一些设计尺寸上的死角。另 外，落实图稿的是施工队的工人，工人往往疏忽大意就会犯错。于是房子装修完了，总是小错误不断。因此小哥觉得大家有必要存一份尺寸标准，监工时要用起来 哦！且看且分享吧！ PART1：【客 厅】 【面积：20平方米～40平方米】 客厅是居室的门面，可以说对家具尺寸的要求是最严格的，多大的沙发配多大的茶几，多远的距离适合摆放电视等等，别看都是一些小数字，却足以令你的客厅成为一个舒适协调的地方。
电视组合柜的最小尺寸？ 【200×50×180厘米】 对于小户型的客厅，电视组合柜是非常实用的，这种类型的家具一般都是由大小不同的方格组成，上部比较适合摆放一些工艺品，柜体厚度至少要保持30厘米；而下部摆放电视的柜体厚度则至少要保持50厘米，同时在选购电视柜时也要考虑组合柜整体的高度和横宽与墙壁的面宽是否协调。 长沙发或是扶手沙发的椅背应该有多高？ 【85至90厘米】 沙发是用来满足人们的放松与休息的需求，所以舒适度是最重要的，这样的高度可以将头完全放在*背上，让颈部得到充分放松。如果沙发的*背和扶手过低，建议增加一个*垫来获得舒适度，如果空间不是特别宽敞，沙发应该尽量靠墙摆放。 扶手沙发与电视机之间应该预留多大的距离？
【3米左右】 这里所指的是在一个29英寸的电视与扶手沙发或和长沙发之间最短的距离，此外，摆放电视机的柜面高度应该在40厘米到120厘米之间，这样才能让看者非常舒适。 与容纳三个人的沙发搭配，多大的茶几合适呢？ 【120×70×45厘米或100×100×45厘米】 在沙发的体积很大或是两个长沙发摆在一起的情况下，矮茶几就是很好的选择，茶几的高度最好和沙发坐垫的位置持平。 目前市场上较为流行的是一种低矮的方几，材质多为实木或实木贴皮的，质感较好。 细节补充： 照明灯具距桌面的高度，白炽灯泡60瓦为100厘米，40瓦为65厘米，25瓦为50厘米，15瓦为30厘米；日光灯距桌面高度，40瓦为150厘米，30瓦为140厘米，20瓦为110厘米，8瓦为55厘米。 PART2：【餐 厅】 【面积：10平方米～20平方米】 用餐的地方是一家人团聚最多的地方，通常也是居室中较为拥挤的一个空间，因为有较多的餐椅需要放置，也是家人同时集中的地方，所以它的尺寸就更要精打细算才能使餐厅成为一个温馨的地方。
南融全际酒店 房卡管理制度 一、房卡类别： a)客房房卡分总裁卡、管理卡、总控卡、领班卡、楼层卡、客人卡。 b)总裁卡、管理卡、总控卡由总经办班相关管理人员持有（总经理、总助） c)领班卡由客房经理和客房主管、领班持有 d)楼层卡由各楼层客房部员工持有 e)客人卡由前台员工制作 注：若领班卡、楼层卡丢失或损坏，应立即上报直属上级，采取相应措施（消磁 和补办），前台需有补办记录，以免酒店遭受损失 二、房卡操作流程 a)领班卡、楼层卡由客房部负责保管，必须存放在指定地方，客房经理须每天检查 b)楼层房卡由客房经理/主管在每日晨会时发放给服务员 c)服务员在领用和交接时必须在工作记录本上记录并签名确认 d)服务员在当班时才有权使用楼层卡在班次结束时需将楼层卡归还 e)服务员非工作需要不得擅自开启客房房门 f)不得随便为他人开启客房 g)客人在楼层要求开门，服务员请客人核对身份，用电话和前台核对（姓名、身份证、 入住日期等），待确认客人身份后方可为客人开启房门 h)按前台指示为客人开启房门 三、房卡保管 a)房卡要时刻随身携带，不得乱丢、乱放 b)严禁将房卡转借他人使用 c)丢失房卡，马上报告主管，查明原因，积极寻找 d)房卡严禁当取电卡使用 e)夜班员工领取领班卡 f)房卡归还必须有记录，并且签名确认 四、客人卡管理制度 a)客人入住前前台人员将客人房间房卡制作给客人 b)原则上每个房间只发放一张房卡，若客人需要两张房卡需收取相应的押金为客人发 放两张房卡并在电脑上注明，在交班记录本上做好交接 c)客人房卡遗失：验明客人身份和登记相符说明规定，向客人收取赔偿费重 新制作一把新的房卡给客人开具赔偿单签客人签字在交班记录本上做好 交接管理人员根据赔偿单到财务处领取新房卡 d)客人房卡损坏：验卡显示房号和客人所报相同，且房卡还未过期核对客
客房服务流程及规范 一、目的:为了规范客房服务人员的服务行为,提高酒店的客房服务水平, 提升客户对服务的满意度,特制定工作标准。 二、员工仪容仪表: 1.手指甲不得超过0、5毫米,时刻保持清洁,不可涂指甲油; 2.经常理发,头发梳理整齐。保持前不遮眉、中不盖耳、后不过领,女士 长发要简单盘于脑后。男士胡须应始终修剪干净。 3.不可佩戴夸张首饰,男士只可带样式简单的手表; 4.整齐穿着酒店制服,制服要求干净整洁; 5.员工不可佩戴有色及大框眼镜; 6.女员工必须着淡妆,不可不化妆或化浓妆。 三、对客服务规范: 1.见到客人要侧身礼让并微笑点头问好; 2.与客人交谈时要有礼貌,必须使用礼貌用语; 3.对客人的额外要求,应立即报告主管; 4.不得向客人索要小费或礼品; 5.如果发现客人在房间里吵闹、发病或醉酒,立即通知主管; 6.非工作需要不得开启或进入客人房间,如因工作需要应先敲门经客人 允许后方可进入; 7.在客人房间做清洁时,不得翻瞧客人物品; 8.不得想客人泄露酒店管理秘密; 9.不得想客人泄露其她客人的信息及秘密; 10.不得私自为客人结账,应礼貌指引到前厅处。 四、物品发放流程及规范: 1.填写申请单 ①客房部凡领用物品,均须规定填写申请单; ②申请单须经主管与经理审批。 2.发放与盘点 ①凭经理审批后的申请单,有客房文员予以发放,发货时要注意物品 保质期,先进先发、后进后发; ②客房文员按时进行月度物品盘点存量。 3.做好发放记录 ①发放物品时,客房文员要以填好的物品领用单(含日期、名称、规 格、型号、数量、单价、用途等)为依据; ②客房文员要及时做好物品管理账簿,保证账物一致。
家具设计地基本尺寸（单位：） 衣橱：深度：一般；推拉门：，衣橱门宽度： 推拉门：，高度： 矮柜：深度：，柜门宽度： 电视柜：深度：，高度： 单人床：宽度：，，；长度：，，， 双人床：宽度：，，；长度，，， 圆床：直径：，，（常用） 室内门：宽度：，医院；高度：，，，， 厕所、厨房门：宽度：，；高度：，， 窗帘盒：高度：；深度：单层布；双层布（实际尺寸） 沙发：单人式：长度：，深度：；坐垫高：；背高： 双人式：长度：；深度： 三人式：长度：；深度： 四人式：长度：；深度 茶几：小型，长方形：长度，宽度，高度（最佳） 中型，长方形：长度；宽度或者 正方形：长度，高度 大型，长方形：长度，宽度，高度（最佳） 圆形：直径，，，；高度： 方形：宽度，，，，；高度 书桌：固定式：深度（最佳），高度 活动式：深度，高度 书桌下缘离地至少；长度：最少（最佳） 餐桌：高度（一般），西式高度，一般方桌宽度，，；长方桌宽度，，，；长度，，，，圆桌：直径，，，， 书架：深度（每一格），长度：；下大上小型下方深度，高度 活动未及顶高柜：深度，高度 木隔间墙厚：；内角材排距：长度（）* 室内常用尺寸 、墙面尺寸 ()踢脚板高；—. ()墙裙高：—. ()挂镜线高：—(画中心距地面高度). ．餐厅
() 餐桌高：—. () 餐椅高；—. () 圆桌直径：二人．二人，四人，五人，六人，八人，十人，十二人. () 方餐桌尺寸：二人×()，四人×()，八人×()， () 餐桌转盘直径；—. 餐桌间距：(其中座椅占)应大于. () 主通道宽：—. 内部工作道宽：—. () 酒吧台高：—，宽. () 酒吧凳高；一. 在客厅 .长沙发与摆在它面前地茶几之间地正确距离是多少？ 厘米 在一个（**高厘米）地长沙发面前摆放一个（**高厘米）地长方形茶几是非常舒适地.两者之间地理想距离应该是能允许你一个人通过地同时又便于使用，也就是说不用站起来就可以方便地拿到桌上地杯子或者杂志. b5E2R。 .一个能摆放电视机地大型组合柜地最小尺寸应该是多少？ **高厘米 这种类型地家具一般都是由大小不同地方格组成，高处部分比较适合用来摆放书籍，柜体厚度至少保持厘米；而低处用于摆放电视地柜体厚度至少保持厘米.同时组合柜整体地高度和横宽还要考虑与墙壁地面积相协调..如果摆放可容纳三、四个人地沙发，那么应该选择多大地茶几来搭配呢？ **高厘米 在沙发地体积很大或是两个长沙发摆在一起地情况下，矮茶几就是很好地选择，高度最好和沙发坐垫地位置持平. .在扶手沙发和电视机之间应该预留多大地距离？ 米 这里所指地是在一个英寸地电视与扶手沙发或长沙发之间最短地距离.此外，摆放电视机地柜面高度应该在厘米到厘米之间，这样才能使观众保持正确地坐姿. .摆在沙发边上茶几地理想尺寸是多少？ 方形：**高厘米. 椭圆形：*高厘米. 放在沙发边上地咖啡桌应该有一个不是特别大地桌面，但要选那种较高地类型，这样即使坐着地时候也能方便舒适地取到桌上地东西. p1Ean。 .两个面对面放着地沙发和摆放在中间地茶几一共需要占据多大地空间？ 两个双人沙发（规格 **高厘米）和茶几（规格**高厘米）之间应相距厘米. .长沙发或是扶手沙发地地靠背应该有多高？
装修常用家具尺寸 在工地 1、标准红砖23*11*6；标准入户门洞0.9米*2米，房间门洞0.9米*2米，厨房门洞0.8米*2米，卫生间门洞0.7米*2米，标准水泥50kg/袋。 在厨房 1.吊柜和操作台之间的距离应该是多少？ 60厘米。 从操作台到吊柜的底部，您应该确保这个距离。这样，在您可以方便烹饪的同时，还可以在吊柜里放一些小型家用电器。 2.在厨房两面相对的墙边都摆放各种家具和电器的情况下，中间应该留多大的距离才不会影响在厨房里做家务？ 120厘米。 为了能方便地打开两边家具的柜门，就一定要保证至少留出这样的距离。 150厘米。 这样的距离就可以保证在两边柜门都打开的情况下，中间再站一个人。 3.要想舒服地坐在早餐桌的周围，凳子的合适高度应该是多少？ 80厘米。 对于一张高110厘米的早餐桌来说，这是摆在它周围凳子的理想高度。因为在桌面和凳子之间还需要30厘米的空间来容下双腿。
4.吊柜应该装在多高的地方？ 145至150厘米。 这个高度可以使您不用垫起脚尖就能打开吊柜的门。 在餐厅 1.一个供六个人使用的餐桌有多大？ 120厘米。 这是对圆形餐桌的直径要求。 140*70厘米。 这是对长方形和椭圆形捉制的尺寸要求。 2.餐桌离墙应该有多远？ 80厘米。 这个距离是包括把椅子拉出来，以及能使就餐的人方便活动的最小距离。 3.一张以对角线对墙的正方形桌子所占的面积要有多大？ 180*180平方厘米 这是一张边长90厘米，桌角离墙面最近距离为40厘米的正方形桌子所占的最小面积。 4.桌子的标准高度应是多少？ 72厘米。
这是桌子的中等高度，而椅子是通常高度为45厘米。 5.一张供六个人使用的桌子摆起居室里要占多少面积？ 300*300厘米。 需要为直径120厘米的桌子留出空地，同时还要为在桌子四周就餐的人留出活动空间。这个方案适合于那种大客厅，面积至少达到600*350厘米。 6.吊灯和桌面之间最合适的距离应该是多少？ 70厘米。 这是能使桌面得到完整的、均匀照射的理想距离。 在卫生间 1．卫生间里的用具要占多大地方？ 马桶所占的一般面积：37厘米×60厘米 悬挂式或圆柱式盥洗池可能占用的面积：70厘米×60厘米 正方形淋浴间的面积：80厘米×80厘米 浴缸的标准面积：160厘米×70厘米 2．浴缸与对面的墙之间的距离要有多远？ 100厘米。想要在周围活动的话这是个合理的距离。即使浴室很窄，也要在安装浴缸时留出走动的空间。总之浴缸和其他墙面或物品之间至少要有60厘米的距离。
干货│家装尺寸数据大全，大家快掏 出小本本记好了！ 一、那些在工地的数据 (3) 二、那些在客厅涉及的家装数据 (4) 三、那些在厨房涉及到的家装数据 (8) 四、那些在餐厅涉及到的家装数据 (9) 五、那些在卫生间涉及到的家装数据 (11)
装修从来不是一件一蹴而就的事 它是一项关乎未来几十年生活质量的细活儿 可以精确到一丝一毫 因此了解一些家具尺寸的数据是非常必要的常识 为了有效避免以下惨烈装修车祸现场 比如心爱的沙发多出一块经常绊倒人 又比如一眼看中的床卧室竟然放不下······
下面各位装修的宝宝赶紧来围观一起涨姿势 一、那些在工地的数据 1、标准红砖23*11*6; 2、标准入户门洞0.9米*2米， 3、房间门洞0.9米*2米， 4、厨房门洞0.8米*2米， 5、卫生间门洞0.7米*2米， 6、标准水泥50kg/袋。
二、那些在客厅涉及的家装数据 1.长沙发与摆放在它面前的茶几之间的正确距离是多少？ 30厘米在一个（240*90*75高厘米）的长沙发面前摆放一个（130*70*45高厘米）的长方形茶几是非常舒适的。两者之间的理想距离应该是能允许你一个人通过的同时又便于使用，也就是说不用站起来就可以方便地拿到桌上的杯子或者杂志。 2.一个能摆放电视机的大型组合柜的最小尺寸应该是多少？ 200*50*180厘米这种类型的家具一般都是由大小不同的方格组成，高处部分比较适合用来摆放书籍，柜体厚度至少保持30厘米；而低处用于摆放电视的柜体
厚度至少保持50厘米。同时组合柜整体的高度和横宽还要考虑与墙壁的面积相协调。 3.如果摆放可容纳三、四个人的沙发，那么应该选择多大的茶几来搭配呢？140*70*45高厘米。在沙发的体积很大或是两个长沙发摆在一起的情况下，矮茶几就是很好的选择，高度最好和沙发坐垫的位置持平。 4.在扶手沙发和电视机之间应该预留多大的距离？ 3米。这里所指的是在一个25英寸的电视与扶手沙发或长沙发之间最短的距离。此外，摆放电视机的柜面高度应该在40厘米到120厘米之间，这样才能使观众保持正确的坐姿。
酒店前台房卡管理制度 一、房卡类别： 1、客房房卡分总控卡、领班卡、楼层卡、客人卡。 2、总控卡店级领导、客房相关管理人员持有（董事长、总经理、副总经理、客务总监、客房经理） 3、领班卡由各楼层领班持有 4、楼层卡各楼层员工持有 5、客人卡由前台员工制作 注：若领班卡、楼层卡丢失或损坏，应立即上报部门，采取相应的措施（消磁和补办），前台要有补办记录，以免酒店遭受损失 二、客人卡的管理制度： 1、将客房匙交给客人前，前台员工必须确认客人身份； 2、前台原则上单人房每间只发放一条房匙，双人房根据客人要求可发放两条房匙，并在电脑中注明； 3、客人房卡遗失： 验明客人身份和登记相符→说明规定，向客人收取或从押金中扣除赔偿费（30元）→重新制作l把新的钥匙给客人→通知房务中心→使用管理卡到该房间插一次卡（做消磁处理），确保插卡前使用的钥匙作废。 4、客人钥匙损坏： A.验卡→显示房号和客人所报相同，且在期限内→重新制作l把钥匙给客人，并向客人致歉。 B.如果卡号不能显示或不能验卡→验明客人身份和登记相符→重新制作1把钥匙给客人，并向客人致歉。 5、客人寄存钥匙： A.听清客人所报房号，请客人稍等→验卡→显示房号和客人所报一致，取房卡填写房号，钥匙插入新房卡，放在寄存抽屉内→客人来取时，验明身份后，交还钥匙，将写房号的房卡撕
毁。 B.如验卡时，房号不能显示，应先验明身份，重新制作钥匙，再进行寄存。 C.如客人寄存时嘱咐他人来取→填写留言单，请客人签字确认→钥匙、留言单放在房卡中存放于收银抽屉内→领取时验明身份→留言单保留在客帐内直至客人退房。 6、客人退房时，前台员工应提醒客人交还房匙→如客人出示的钥匙没有房卡或押金单证明其房号，必须验卡验证无误后，方可通知客房服务员查房并办理退房手续。 7、退房时，客人将钥匙留在房间：客房服务员查完房交到前台。凡有折痕、断裂、明显污迹、坏的钥匙，交前台主管保管。 8、未经登记客人许可，不得为任何来访者开启客人房间或发卡给来访者； 9、任何服务员如发现房卡遗留于公共场所，应立即交当值主管，送回前台接待处处理； 10、客房服务员不得对客人以错放锁匙在房间内为由，随便开房门让客人进入，应即时打电话到前台接待处核实客人身份，如有任何疑问，应请客人到前台接待处办理补匙手续。 11、前台服务员每班交接时，必须核对客人钥匙数量。发现任何缺失必须上报并在交接本上作记录。 10、所有IC卡上不能贴房号。
1.商品图片的尺寸：宽500*高500像素，大小在120KB以内，要求JPG或GIF格式，到发布宝贝页面上上传图片。最好大于312*310px 2.店标图片的尺寸：宽100*高100像素，大小在80K以内，支持JPG或GIF格式，动态或静态的图片均可。上传步骤：“管理我的店铺”-“基本设置”-“店标”-“浏览”-“确定” 3.宝贝描述图片的尺寸：没有特殊要求，可根据需要宽500*高500像素，大小在100K以内，这样图片的打开速度较快。要求JPG或GIF格式，静态或动态均可。将图片上传到电子相册，再复制到商品页面中去。 4.公告栏图片的尺寸：宽不超过480像素，长度不限制，大小在120KB以内GIF或JPG格式，动态或者静态均可。上传“管理我的店铺”-“基本设置”-“公告栏”-“确定”。 5.宝贝分类图片尺寸：宽不超过165,长度不限制，大小在50KB以内，要求GIF或JPG格式，动态或者静态均可，先将图片上传到电子相册得到一个缩短网址后进入“管理我的店铺”-“基本设置”-“宝贝分类” 6.旺旺头像图片尺寸：宽120*高120像素，大小在100KB以内，格式为JPG或GIF，动态或者静态均可。 7.论坛头像图片尺寸：最大为宽120*高120像素，大小在100KB以内，GIF或者JPG格式，动态或者静态图片均可。上传方法“我的淘宝”-“个人空间”-“修改资料”-“上传新头像”。 8.论坛签名档图片尺寸：宽468*高60像素，大小在100KB以内，JPG或者GIF格式，动态或者静态均可，上传“我的淘宝”-“个人空间 淘宝店铺装修最佳尺寸 普通店铺 1.店标 大小：100*100px <=80k 代码：无（图片做好后直接上传） 格式：jpg、gif 设置：管理我的店铺—基本设置—店标—浏览—选择本地做好店标文件 2. 店铺公告尺寸：320*400 3.宝贝分类尺寸:88*88和88*30（宝贝分类含3个) 4.店铺介绍尺寸：600*450 5.计数器尺寸:137*94 6.论坛签名尺寸:468*60
前台房卡管理规定 一、房卡类别： 1、客房房卡分总控卡、领班卡、楼层卡、客人卡。 2、总控卡店级领导、客房相关管理人员持有（董事长、总经理、副总经理、客务总监、客 房经理） 3、领班卡由各楼层领办持有 4、楼层卡各楼层员工持有 5、客人卡由前台员工制作 注：若领班卡、楼层卡丢失或损坏，应立即上报部门，采取相应的措施（消磁和补办），前台要有补办记录，以免酒店遭受损失 二、客人卡的管理制度： 1、将客房匙交给客人前，前台员工必须确认客人身份； 2、前台原则上单人房每间只发放一条房匙，双人房根据客人要求可发放两条房匙，并在电 脑中注明； 3、客人房卡遗失： 验明客人身份和登记相符→说明规定，向客人收取或从押金中扣除赔偿费（30元）→重新制作l把新的钥匙给客人→通知房务中心→使用管理卡到该房间插一次卡（做消磁处理），确保插卡前使用的钥匙作废。 4、客人钥匙损坏： A.验卡→显示房号和客人所报相同，且在期限内→重新制作l把钥匙给客人，并向客人 致歉。 B.如果卡号不能显示或不能验卡→验明客人身份和登记相符→重新制作1把钥匙给客 人，并向客人致歉。 5、客人寄存钥匙： A.听清客人所报房号，请客人稍等→验卡→显示房号和客人所报一致，取房卡填写房号， 钥匙插入新房卡，放在寄存抽屉内→客人来取时，验明身份后，交还钥匙，将写房号的房卡撕毁。 B.如验卡时，房号不能显示，应先验明身份，重新制作钥匙，再进行寄存。 C.如客人寄存时嘱咐他人来取→填写留言单，请客人签字确认→钥匙、留言单放在房卡 中存放于收银抽屉内→领取时验明身份→留言单保留在客帐内直至客人退房。 6、客人退房时，前台员工应提醒客人交还房匙→如客人出示的钥匙没有房卡或押金单证明 其房号，必须验卡验证无误后，方可通知客房服务员查房并办理退房手续。 7、退房时，客人将钥匙留在房间：客房服务员查完房交到前台。凡有折痕、断裂、明显污 迹、坏的钥匙，交前台主管保管。 8、未经登记客人许可，不得为任何来访者开启客人房间或发卡给来访者； 9、任何服务员如发现房卡遗留于公共场所，应立即交当值主管，送回前台接待处处理； 10、客房服务员不得对客人以错放锁匙在房间内为由，随便开房门让客人进入，应即时打电 话到前台接待处核实客人身份，如有任何疑问，应请客人到前台接待处办理补匙手续。 11、前台服务员每班交接时，必须核对客人钥匙数量。发现任何缺失必须上报并在交接本上 作记录。 12、所有IC卡上不能贴房号。