Transient performance characteristics of a hybrid ground-source heat pump in the cooling mode

测试期间室外平均温度 36.47℃，相对湿 相对湿度 73.53%RH。流量、电量测试记录见
图 3、图 4。根据测试记录分析计算的机组能效 与系统能效分别见表 3、表 4。测试结果表明：
度 58.44%RH；空调区域平均温度 24.22℃，
（1）测试期间冷却水温变化见图 3。工况 一（图 3 左）冷却水进、出口平均温度为 31.2 ℃、34.1℃，温差为 2.9℃；冷冻水进、出口平 均温度为 12.1℃、14.7℃，温差 2.7℃。工况二 （图 3 右）冷却水进、出口平均温度为 30.3℃、 32.4℃，温差为 2.1℃；冷冻水进、出口平均温
35.0 30.0 25.0 20.0 15.0 10.0
5.0 0.0
13:00
13:40
14:20
冷却出水/℃ 冷冻回水/℃
15:00
15:50
冷却进水/℃ 冷冻供水/℃
图 3 测试期间温度变化曲线（左：工况一，右：工况二）
（4）二机二泵的系统能效 COP 为 2.6（1# 主机两台压缩机工作，2#主机一台压缩机工作）， 一机一泵的系统能效 COP 为 2.4。系统能效=（系 统总制冷量+热回收量）/系统总的输入功率（机 组+水泵）。
2.1 测试 1.测试仪器 测试仪器见表 3。表中仪器经过湖北省计量
测试技术研究院标校。 2.测试方案与测试工况
机组能效限定值及能源效率等级》的二级要求。 （2）地埋管热工性能测试。原始地温 18.7
℃。散热模式：地埋管单位换热量为 61.5～ 60.1W/m 井深（单 U，埋管深度 80m），进水温度 35.35℃，回水温度 31.8～32.4℃。取热运行模 式：35.1～35.9 W/m，进水温度 9.2℃，回水温

地源热泵冷热水机组性能的ARMA模型许伟明;王瑞祥;曹旭明【摘要】Auto-regressive and moving average model （ARMA） is an important method of time series analysis, as well as an effective means to find out the performance of ground-source heat pump （GSHP）. The ARMA model of GSHP was established with the return water tempe%自回归滑动平均模型（Auto-Regressive and Moving Average Model,ARMA）是研究时间序列的重要方法,是分析地源热泵冷热水机组性能的有效手段之一.建立了热泵冷热水机组使用侧回水温度Te2和埋管侧回水温度Tc2的ARMA模型,利用该模型对北京中关村国际商城可再生能源示范项目的地源热泵冷热水机组性能的实际运行状况进行了分析诊断.【期刊名称】《北京建筑工程学院学报》【年(卷),期】2011(027)002【总页数】5页(P51-55)【关键词】地源热泵冷热水机组;性能预测;ARMA模型;时间序列法【作者】许伟明;王瑞祥;曹旭明【作者单位】北京建筑工程学院北京市绿色建筑与节能技术重点实验室,北京100044 ;北京建筑工程学院北京市绿色建筑与节能技术重点实验室,北京100044 ;北京城建安装公司,北京100045【正文语种】中文【中图分类】TU822地埋管地源热泵空调系统在夏季,热泵冷热水机组把冷凝器的热量释放给土壤,蒸发器产生的冷水送至空调末端设备进行供冷.在冬季,热泵冷热水机组从土壤中吸收热量,冷凝器产生的热水送至空调末端设备进行供暖.[1]对地源热泵冷热水机组运行性能的精确预测是HVAC最优控制的前提,尤其在地源热泵技术的应用中,热泵机组运行性能的预测显得更为重要和必要.在实际工程运行中,地源热泵系统运行性能的观测较为容易得到的是使用侧和埋管侧的进出水温度,不易得到其流动介质的流量,使得传统的建模方法存在一定的局限性,不能对系统运行性能进行预测与在线诊断[2].Hikmet Esen等人应用神经网络模型(ANN)、加权神经网络模型(SWP-ANN)[3]、自适应模糊评价模型(ANFIS)[4]和支持向量机方法(SVM)[5]模拟预测水平埋管式地源热泵的热泵机组运行效率COP.输入参数:室外环境温度、室内房间温度、地下埋管 1m处的温度、地下埋管 2m处的温度、地下埋管进、出口温度和进、出冷凝器的空气温度,输出参数:热泵机组的 COP.比较 ANN、SWP-ANN、ANFIS和SVM的模拟的 COP值与实际的 COP值,得到 ANN的 RMS(根值平方)为 0.007 4,R2为 0.9999和 cov为 2.22;SWP-ANN的 RMS为 0.002,R2为0.999 9和cov为 0.076;ANFIS的 RMS为 0.0047,R2为 0.999 9和 cov为 0.136 3;SVM的RMS为0.002 722,R2为 0.999 999和 cov为 0.077 295.SVM模型优于神经网络(ANN)和自适应神经模糊推理系统(ANFIS),其因它含有较少变量和唯一的支持向量.人工智能模型(如:神经网络模型 ANN)广泛应用于 HVAC系统中,且主要研究集中在对制冷或制热机组性能的模拟,如Swider比较ANN模型和传统的经验模型的热泵机组稳态性能[6];Kalogirou和Bechtler等人利用 ANN模型模拟预测稳态的热泵机组的性能[7-8];Arcaklioglu和 Ertunc等人运用 ANN模型预测热泵机组的运行性能[9-10].目前,国内对地源热泵机组在整个系统中的运行特性的相关研究较少[11],大多还只是在实验研究阶段.由于在实际工程应用中,地源热泵机组结构复杂且影响机组运行特性的因素较多,传统建模方法很难达到精度要求[12].时间序列分析采用参数模型对所观测到的有序的随机数据进行分析与处理的一种数据处理方法,分析研究观测数据内在的各种数学统计规律,并利用现在和过去的观测数据来预测或控制未来值[13].时间序列分析不需要知道影响预测变量的因果关系,只要有足够多的数据量就可以建立一个合理的时间序列模型.通过时间序列分析可以适度检验理论性模型与数据的正确性,检验模型能否正确地表征所观测的客观现象;客观地描述系统特性及其运行状态,从而客观地认识并解释系统及其规律;预测系统的未来行为和控制系统的未来行为.时间序列分析按应用背景可分为预报分析,控制分析和诊断分析等.时间序列分析方法在地埋管地源热泵冷热水机组的应用研究很少,本文的研究目的是以北京中关村国际商城可再生能源示范项目的垂直埋管式地源热泵空调系统为背景,对项目验收资料中所记录的历史数据建立该项目热泵冷热水机组的 ARMA时间序列模型,得到机组使用侧和埋管侧回水温度的数学表达式,模拟预测机组的运行性能,并检验其R2、COV和 EEP值.结果表明:在只有有限对观测数据即机组使用侧和埋管侧的进、出水温度四组参数条件下,可利用 ARMA时间序列模型对机组运行状态进行分析,既能避免传统方法的缺点,又能满足运行性能的预测和在线故障诊断的需要.1 时间序列分析方法1.1 时间序列模型时间序列靠数据顺序和大小,蕴含着客观世界及其变化的信息.一般的时间序列由趋势变化、季节性变动、循环变动、随机变化四部分构成.时间序列是事物发展持续性的表征;是时间的函数但不一定时严格函数;每个时刻的取值具有一定随机性;前后时刻数据有一定相关性.AR模型、MA模型和ARMA模型是时间序列模型中最常用的三种形式,本文重点研究 ARMA模型.1.2 ARMA(Auto-Regressive and Moving Average Model)模型ARMA模型既揭示了观测数据的数学统计特性,也揭示了观测数据所对应系统的动态特性[14].对于一个平稳、零均值的时间序列{Xt},t=1,2,…,N,都可用下式 (1)表示:式中:Xt——时间序列{Xt}在 t时刻的元素;φi(i=1,2,…,n)——自回归参数;φj(j=1,2,…,m)——滑动平均参数;εt——残差序列,且εt为白噪声,服从均值为0,方差为σ2的正态分布,记为εt～NID(0,σ2).式(1)称为 n阶自回归 m阶滑动平均模型,记为 ARMA(n,m)模型.时间序列{Xt},可看成某一系统的实际输出,φi、φj和εt是基于 {Xt}按某一方法估计出 ARMA模型的参数,因而,系统特性与工作状态的所有信息都凝聚蕴含在这 N个数据大小和先后取值之中,不仅可依据 ARMA模型进行系统分析、模式识别、故障诊断,而且还可复原原始信息.1.3 时间序列分析方法时间序列是系统历史行为的客观记录,包含了系统动态特性的全部信息,同时,这些信息也具体表现为时间序列中观测值之间的统计相关性.时间序列分析方法从系统角度来看,它表现着相应系统的动态过程,包含着系统的输入、系统本身的特性、系统同外界相互联系三者的关系.2 地源热泵冷热水机组模型的建立与性能模拟地源热泵冷热水机组使用侧的实际进出水温度在运行中主要受到建筑的负荷、连续/间歇运行模式和机组运行性能的影响,地埋管侧的实际进出水温度在运行中主要受到土壤温度、建筑负荷和连续/间歇运行模式的影响.地源热泵机组不仅要和空调末端系统负荷相匹配,还要和地下土壤的温度变化特性相适应.本文将地源热泵冷热水机组整个系统看作一个“黑箱”,基本不考虑系统内部的具体结构和干扰因素,而是通过分析历史观测输入与输出数据,建立冷热水机组使用侧回水温度和埋管侧回水温度与输入输出参数的数学模型,利用此模型模拟预测机组运行性能,从而为机组的优化运行提供依据.2.1 地源热泵冷热水机组模型建立图1为地源热泵冷热水机组结构示意图,在机组运行过程中,组成该系统的各个部件同时在运行,对系统的状态产生影响,每个部件的运行参数与其他部件的运行参数是相互影响,相互关联的.图1 地源热泵冷热水机组工作原理从系统辨识的角度看,其输入参数为使用侧供水温度和地埋管侧供水温度,输出参数为使用侧回水温度和地埋管回水温度,基于 ARMA(n,m)模型建立输出参数与输入参数之间的关系:[15]式中:Te1,t——在 t时刻使用侧的供水温度,℃;Te2,t——在 t时刻使用侧的回水温度,℃;Tc1,t——在 t时刻埋管侧的供水温度,℃;Tc2,t——在 t时刻埋管侧的回水温度,℃;A、B、C、D、E、F——模型的阶数 ;α、β、γ、ω、λ、θ——各项系数 ;——白噪声.2.2 ARMA(n,m)模型求解现以北京中关村国际商城可再生能源示范项目的垂直式埋管地源热泵冷热水机组采暖时期的运行数据为基础利用式(2)、(3)确定该冷热水机组输入输出参数之间的定量关系.该商场利用土壤源热泵技术作为冬季空调热源和夏季空调冷源.其冷热水机组 3台,单机制冷量 2 388 kW,制热量 2 206 kW.地下换热器共 1 060个,设计孔深为 123m,采用双U型埋地换热器.数据采集:2009年 2月份地源热泵冷热水机组采暖时期的使用侧进、出水温度(Te1,t、Te2,t)和埋管侧进、出水温度(Tc1,t、Tc2,t).商场采用间隔运行模型,冬季每天运行 13 h,共测得 189对有效运行数据,见图 2(图中未标示机组不运行情况).图3所示冬季某天使用侧和埋管侧供、回水逐时温度.在实际观察中得到的时间序列大多数都是非平稳的,需对 189对有效数据进行预处理(直观分析、特征分析、相关分析),并进行数据平稳性(季节项提取、趋势项提取、周期项提取)检验和零均值处理,确保输入数据为平稳时间序列{Xt}.采用广义最小二乘法分别计算公式(2)、(3)中不同阶次 A、B、C、D、E、F的各项系数,对应的 Te2、Tc2模拟值与实际值差值的标准方差R2、协方差COV和期望偏差百分率 EEP,从而确定阶次和各项系数.利用 MATLAB求得 Te2、Tc2的表达式[16-17],如式(4)、(5):图2 进出地源热泵机组水温图3 冬季某天地源热泵机组供回水逐时温度3 模型正确性验证及结果分析为验证模拟结果的正确性,采用如下几个判断准则对模拟结果进行误差分析:3.1 标准方差(R2)式中:ΔTi——模拟值与实际值的温度差值,℃;—差值温度的平均值,℃;n——模拟值的个数.3.2 协方差(COV)式中:E(X)——X的期望值.3.3 期望偏差百分率(标准方差和样本输出值中最大值的绝对值之比的百分数)(EEP)式中:ΔTmax——模拟值与实际值差值的最大温度,℃.3.4 结果分析通过计算式(4)、式(5)得到 2月份地源热泵冷热水机组运行时的使用侧、埋管侧模拟的回水温度如图 4、图 5所示(图中均未标示机组不运行的情况 ).Te2、Tc2的模拟值与实际值差值(ΔTe2、ΔTc2)的R2、COV和 EEP列于表 1.从表 1中可以看出,所Te2 Tc2建 ARMA模型的正确性.图4 使用侧回水温度模拟值与实际值图5 埋管侧回水温度模拟值与实际值表 1 模拟值与实际值结果分析项目R2 COV EEP ΔTe2 0.613 9 0.4155 0.361 1 ΔTc2 0.836 7 0.3888 0.309 9从式(4)可以看出某一时刻的使用侧回水温度与该时刻使用侧进水温度、埋管侧进水温度和前一时刻的使用侧回水温度有关,且受该时刻使用侧进水温度影响较大,供水温度反应的是建筑负荷作用的结果.同时,也反应了在使用侧进水温度不变的情况下,使用侧回水温度提高随埋管侧进水温度的升高而升高.从式(5)可以看出埋管侧回水温度受使用侧进水温度的影响较小,主要取决于过去一段时间的负荷变化.4 结论本文通过建立地源热泵冷热水机组的 ARMA模型,模拟机组冬季使用侧回水温度与埋管侧回水温度,得到 Te2和 Tc2模拟值与时间值差值的 R2、COV和 EEP分别为0.613 9和 0.8367、0.4155和0.3888、0.361 1和 0.309 9.本文采用的时间序列分析方法可以不必考虑地源热泵冷热水机组的复杂构造,避免应用一些经验公式,同时也提高了模型的模拟精度.若样本数据可靠,可满足机组的运行性能预测和在线故障诊断的需求.参考文献:[1] 陆耀庆.实用供热空调设计手册:第 2版[M].北京:中国建筑工业出版社,2008[2] Nielsen H A,Madsen H.Modelling the heat consumption in district heating systems using a grey-box approach[J].Energy andBuildings,2006(1):63-71[3] Hikmet Esen,Mustafa Inalli et al.Forecasting of a ground-coupled heat pump performance using neural networks with statistical data weighting pre-processing[J].International Journal of Thermal Sciences,2008,47(4):431-441.[4] Hikmet Esen,Mustafa Inalli et al.Artificial neural networks and adaptive neuro-fuzzy assessments for groundcoupled heat pump system[J].Energy and Buildings,2008,40(6):1074-1083[5] Hikmet Esen,Mustafa Inalli et al.Modeling a ground coupled heat pump system by a support vector machine[J].Renewable Energy,2008,33(8):1814-1823[6] Swider DJ.A comparison of 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山东建筑大学地源热泵研究所简介1.基本概况本研究所成立于2000年初。

由5名教授、4名副教授、3名高级工程师和十余名研究生组成。

采用理论研究与工程实践相结合的技术路线，系统深入地研究了地埋管浅层地热能利用中地热换热器的传热机理与优化设计方法、岩土热物性测试及地埋管传热强化等关键技术，开拓出大空间多维非稳态地下传热分析与工程应用的新途径。

经过近十年的潜心研究与技术开发，形成了系统的地埋管浅层地热能利用技术体系。

该技术体系的核心是：首次求得地热换热器传热分析中钻孔内准三维传热模型、钻孔外有限长竖直和倾斜线热源模型以及有渗流时导热与对流复合作用的二维非稳态传热模型的解析解，创建了基于这些解析解和叠加原理的地热换热器传热分析方法；基于这些解析解和新模型，开发了地热换热器优化设计模拟软件；研发了能够用于现场确定深层岩土热物性的测试方法和测试仪；深入研究了地热换热器强化传热技术，探索了各种组成物对水泥砂浆回填材料导热系数的影响规律，开发了基于水泥砂浆、石英砂和改性添加剂的高性能回填材料。

所长方肇洪，教授。

1968年毕业于清华大学动力机械系。

1981年和1987年先后取得清华大学工学硕士和工学博士学位。

中国建筑学会建筑热能动力分会理事。

美国供热制冷空调工程师协会（ASHRAE）会员、国际地源热泵协会（IGSHPA）会员。

方肇洪教授在英国曼彻斯特大学理工学院、加拿大不列颠哥伦比亚大学进行合作研究各一年，在美国俄克拉荷马州立大学学习考察地源热泵技术三个月。

副所长刁乃仁，教授，获清华大学博士学位，山东建筑大学热能工程学院院长。

山东省建筑节能与可再生能源利用专家、国际地源热泵协会会员、山东建筑学会暖通空调分会与热能动力分会副主任委员。

曾赴法国进行合作研究一年。

2.工程应用初步统计本所研究的地源热泵技术体系在12个省市300余项浅层地热能利用工程中应用，研究所承接的部分应用项目情况见表1；设计模拟软件被清华大学、香港理工大学以及北京华清集团等100多个高校和企业采用；研制的热物性测试仪对北京奥林匹克公园、奥体网球馆及济南奥体中心等重点工程深层岩土热物性进行了测试。

OutlineThe PAN-A series is a high-performance, highly reliable DC power supply unit featuring regulated variable voltage. These units are suitable for use in a range of fields including research and development, quality control, and production. The PAN -A series consists of a pre-regulator using FETs and a series regulator using power transistors, providing the high-quality input characteristic of the latter as well as the low power-source harmonic distortion of choke input type phase control.To achieve the high reliability and safety important for power supply, components of sufficient derating and long-proven mounting techniques are used throughout. All models are care-fully designed and furnished with over voltage protection (OVP) and various safety functions.s Low temperature driftCarefully selected components, improved circuit design, and heat dissipation based on the forced air cooling design have achieved a low-temperature drift of 100 ppm/°C (con-stant voltage characteristic) and 300 ppm/°C (constant cur-rent characteristic).s Quick transient responseSince the Error Amplifier has a characteristics of wide fre-quency bandwidth, stable gain, less phase shift and high loop gain, the PAN-A series is equipped with a highly stable and low output impedance as well as quick response to sud-den change of the load. (Typical response time is 50µs)s Low ripple noise voltageNot only the effective value but also the peak value are kept low.s Various safety functionsVarious safety functions, such as an overvoltage protector (OVP) and an overheating protection circuit, are provided. s ApplicationIncorporates a wide range of functions capable of system-atization, including analog signal- or computer- (GPIB) based remote control, remote sensing, and master-slave-con-trol serial and parallel operations. (The PAN350-3.5A and PAN600-2A cannot be operated in series.)Features0 to 600 V DC, 0 to 50 A, 28 modelsLow noise and highly stable output achieved using the series regulation systemBasic DC power supplies, superior for general-purpose use.Front PanelRear PanelOutput ON/OFF switchON/OFF can also be controlledwith external signals.Alarm display“ALM” lights up when theOVP circuit is activated.Voltmeter, amperemeterHigh-intensity LEDs offeringgood visibility are used. Thesemeters indicate output voltageand current as well as outputlimit values.Limit switchIf this limit switch is helddown, the voltmeter indicatesthe voltage limit value, and theamperemeter indicates thecurrent limit value.Preset OVP switchIf this switch is held down,the voltmeter indicates the presetOVP value.OVP variable resistorThis is used to preset theactuating point for OVP.Sub-panel coverA remote-control presetswitch and variable resistorsfor various calibrations(with offset and full-scaleadjustments) are locatedbeneath the cover.Front-side outputterminalsNote:There is no auxiliaryoutput terminal on the frontpanel of Model PAN16-50A.Voltage and current presetvariable resistorsShock-resisting 10-turn helicalpotentiometers are used (theoreticalresolution: 0.018%; a guard cap is usedto change to a fixed or semi-fixedknob). These variable resistors are ofa wire-wound design, and slidingsurfaces are treated to preventoxidation.Power switchThe 175W and 350W modelsare designed so that therectification circuit is shutdown if the OVP function isactivated. The 700W and1000W models, which use acircuit protector (NFB), aredesigned so that the powerswitch is automatically shutdown if the OVP function isactivated.Control terminalsThese terminals are used forremote control, parallel, orseries operations.Note:The arrangement ofsensing terminals for thePAN350-3.5A andPAN600-2A differ fromother models: Terminal 1is unassigned.Sensing terminalsThese terminals are used forremote sensing.Output terminals Forced air-cooling exhaust portAC input terminals(175W and 350W type haveAC receptacle instead.)Fuse holder(175W and 1000W type havethis holder inside of the unit.)Chassis ground terminalProtection SystemFailures or malfunctions of a power supply unit may cause an operational shut-down of the overall system or damages to expensive loads. Therefore, failure-free operating performance is extremely important. And should a failure occur, protection circuits must be provided that can ensure that no accident oc-curs.s Overvoltage protector (OVP)If an overvoltage is generated by an operating error or acci-dent, the OVP instantaneously (function pulse width: 50 ms)shuts down the power switch circuit protector, and protects the connected load. (Type 0 and Type I 2 models employ a gate block system, and shut down their rectification circuits.) Since the OVP used in the PAN-A series is of a preset design, the operating voltage can be preset by pressing the preset knob on the panel, while looking at the voltmeter.The operating voltage can be checked without interrupting the OVP operation even during aging.s Overheat protection circuitThis circuit functions to turn off the power switch, if the tem-perature of some of the main components in the equipment rises higher than a specified value. A thermal fuse incorpo-rated in the main- or sub-transformer further improves safety performance.s Voltage detection circuitIf the smoothing electrolytic capacitor voltage rises above a specified level owing to an operating error involving the re-mote selection switch inside the panel or to a failure of the rectification circuit, the voltage detection circuit functions to instantaneously shut down the rectification circuit.s Surge absorberThis protect the power supply unit from surge currents gener-ated in the power line by lightning.s Reverse connection prevention circuitThis circuit protects the power supply unit even if a reverse polarity voltage is applied to the output terminals.s Overcurrent detection circuitUsing a comparison amplifier, this detection circuit constantly monitors the output current. It prevents a current from in-creasing beyond the rated value in the event of an over-input caused by remote control, and also prevents overcurrents caused by misoperation of the remote control selector located inside the panel.ApplicationThe PAN-A series enables remote control of output voltage and current using analog signals. External contact points can also be used to control ON/OFF operationss Remote-control using external voltageItem to be cntrolled Control voltage*Input impedance Output voltage 0 to approx. 10V Approx. 10 k ΩOutput current0 to approx. 10VApprox. 25 k Ω* The control voltage circuit should be floated (insulated), since "com-mon" is connected to the positive voltage side.s Remote-control using external resistorItem to be controlled Control resistor*Current in resistor Output voltage Approx. 10 k ΩApprox. 1 mA Output currentApprox. 10 k ΩApprox. 0.4 mA* For the control resistors, use metal film or wire wound resistors of 1/2 W or larger capacity, a low temperature coefficient, and good aging stability .s Remote sensingq This is a method used to compensate for the voltage drop caused by the cable resistance between the power unit and the load and contact resistance. The problem of voltage drops becomes more serious as the current becomes larger. By turning on the “Sens”switch at the rear panel and transferring the voltage sensing point to the end of the load , a voltage drop of up to 0.6 V can be pre-vented on one side. (Max. output voltage must be reduced, if the prevention of a voltage decrease of 0.3 V or higher is desired.)Note: For the sensing function in 16V models, the maximumoutput voltage of this series is 105% of the rated voltage.Since the maximum output voltage of the 16V models is 16.8V , an attempt to compensate for 1.2 V (0.6 V for one way ×2), the full-compensating voltage, will disable output of the rated voltage. In this case, use wires that have a larger cross-sectional area with less voltage drop, so that voltage drops are 0.4 V or less one-way.q Connect an electrolytic capacitor with a capacity of a several thou-sand to several tens of thousand of microfarads to the load end,paying attention to the polarity and making the lead wires as short as possible. The reasoning here is as follows. A long cable to the load has nonnegligible inductance, which raises the output imped-ance of the power supply unit to the load. A large capacitance connected to the load end can prevent this. Particularly when deal-ing with a load like an inverter, which turns the current on and off with high frequency, connect a capacitor with a capacity larger than several thousand microfarad using the shortest possible lead wires.s Output ON/OFF controlq Using external contact point signals, it is possible to turn the out-put on and off.*Use external contact points with rated values higher than 10 VDC and 10mA.s Master-slave control of parallel operation(This control is possible only for parallel-connected units of the same model.)q The current capacity can be increased by connecting a multiple number of units of the same model in parallel. Output control can be performed by a master unit.q Use only one master unit to perform remote sensing, remote con-trol, and output on/off control.*For one master unit, a maximum of two slave units can be con-nected in parallel.s Master-slave control of series operation(This control is possible only for series-connected units of the same model.)q The output voltage can be increased by connecting a multiple num-ber of units of the same model in series. The unit on the top (i.e.,the positive side) plays the role of master, and can control the out-put of the slave unit(s).q The example shown above is a dual tracking power supply that can vary positive and negative voltages simultaneously.*The number of slave units that can be connected in series depends on the rated output voltage and the voltage to ground of the units connected in series. Example: When connecting the PAN35-10A(rated output voltage: 35 V) in series, the voltage to ground is ±250 V , namely, 250 (V)÷35 (V) 7.1. Therefore, the max. num-ber of units to be connected in series, including one master, is seven.Note:PAN350-3.5A and PAN600-2A do not offer master-slavecontrol and serial operation functions.Applications Computer Controlq To control the power supply from a PC via a GPIB inter-face, connect a PIA4800 series power supply controller to a PAN-A series power supply.* Combine the PIA4810 power supply controller and OP01-PIA or OP02-PIA control board for two-channel analog con-trol with the PIA4800 series. Since the PIA4810 controller incorporates four control boards, up to eight channels ofDC power supplies or loads can be controlled.power supply controller allows the extension of a system power supply.s Connection concept for the PIA4800 series power sup-ply controllersq For PAN-1 (OP01-PIA)To set and read back voltage and current, to turn output on/off, or to read out a variety of monitoring signals, attach DIN connectors (to output monitoring signals) to the rear of a PAN-A series power supply, and connect a terminal unit (TU02-PIA) and shunt unit (SH series).* Installing DIN connectors is optional and entails separateq For PAN-3 (OP01-PIA)To set the voltage and current, connect signal cables to the control terminal board at the rear of the PAN-A series.Connection T ypePAN-1PAN-3Output Voltage setting ✔✔Output Current setting ✔✔Output Voltage readback ✔Output Current readback ✔Output ON/OFF✔Remote/Local switchingv (*1)Power switch OFF monitoring v (*2)C.V mode monitoring v (*2)C.C mode monitoringv (*2)s Description of Control*1: This is a manual operation using S1 (CV) and S2 (CC) on the control panel of the PAN-A series main unit.*2: This requires modifications to connect a DIN connector to the main unit.*Precautions1.For the PAN600-2A, no units other than the PIA4810 power supply controller or OP02-PIA control board may be used.2.For more information on the PIA4800 series, see the individual catalog for that series.3.If you have any inquiries, contact a Kikusui agent.ReferenceCurrent with peaksPeak valueCC preset value Mean value(Meter indication)Pulse-formed load current Peak valueCC preset value Mean value(Meter indication)LoadSince the PAN-A series is designed for a wide range of applications,there are a variety of loads to be connected. Depending on the type of load, direct connection may cause problems or malfunctions, and some countermeasures should be taken.s Load with accumulated energy, such as a batteryWhen connecting a load with accumulated energy, such as a battery,to the PAN-A series output, a large current may flow from the load to the internal capacitor through the output control circuit protection diode. This current may burn internal components or shorten the load's life.In such a cases, therefore, connect a reverse current protection diode be-tween the power supply unit and theload as shown below.s When the load current has peaks or a pulse waveformIn the case of a digital or a motor driving circuit, a load current wave-form will instantaneously reach the rated current range if the peak value exceeds the rated value, even if it is within the rated value on the meter indication (mean value). If so, the output voltage will drop and appear unstable. The basic remedy is to increase the output cur-rent (i.e., increase the current preset value or current capacity). How-ever, if the pulse width is narrow or the peak value is low, it may prove effective to connect a large-capacitor to the load end.s Inductive loadq The counter electromotive force generated by turning on and off of the power supply, or changing the voltage setting is shunted by protection diode D 1 inserted in parallel with the output so that the power supply is not damaged.q When pulse noise generated from an inductive load is impressed at the same polarity as the power supply, protect the power supply by inserting diode D 2 in se-ries with the power supplyand inserting a noise pre-vention CR absorber across the switch.s When the output is turned on and off with a mechanical switch q When a DC output of 100V or more is opened and closed with a switch, arc discharge, etc. will cause the switch contacts to notice-ably wear and generate noise. This noise may enter the power sup-ply differential amplifier through the load line and cause the out-put to become unstable. Take noise countermeasures by inserting a CR absorber near the contacts, the same as for an inductive load.q When performing remote sensing, always turn thesensing line on or off si-multaneously.Rush CurrentWhen turning on the power, a rush current may flow, depending on when the power is turned on. Such rush currents are caused by mag-netic saturation of the transformer core material. Theoretically, if the power is turned on near the phase angle 90°(π/2) of the voltage wave-form, no rush current is generated. If the power is turned on at a timing corresponding to the phase angle 0°(zero cross), however, a max. current is generated. This transient phenomenon is shown be-low. In practice, however, the presence of a rush current is deter-mined by the hysteresis characteristic of the B-H curve of the core material, the direction of residual magnetic flux upon switch-off, and/or the impedance of the AC line to which the PAN-A series is con-nected. If the power is turned on simultaneously for a multiple num-ber of the PAN-A series units, check that the AC line capacity or the switch board capacity is sufficient.q Typical (max.) rush current value for the PAN-A series(Half wave width of current waveform: approx. 5 ms)Type 175W(0)350W(I 2)700W(I 3)1000W(II)AC inputPower voltage 100V 100V 100V 100V Peak current100A200A350A450ANegative voltageRegardless of the position of the output switch (ON/OFF), when the voltage and current preset variable resistors are turned fully counter-clockwise, negative voltage in the 0 to 0.6 V range is generated at the output end. This voltage acts to generate approx. 10 mA of reverse current through the load. The PAN-A series may be inadequate for applications in which the load should be kept free from serious influ-ence by such a reverse current.Output terminals on the front sideThe output terminals on the front side are auxiliary output terminals.These terminals may not satisfy the specification. To satisfy the speci-fication, use output terminals on the rear panel. Be sure to use the attached terminal cover for models with rated output voltage higher than 55 V.Output wiresThe sectional area, current capacity, and resistance of these wires areas shown below.Nominal Current estimated Current for allowable Typicalresistancesectional area for DC output wireconductor temperature 60°C at 20°C (Ambient temperature 30°C)2(mm 2)10(A)27(A)Approx.9 (Ω/km)5.52049383061 2.21450881.2Current waveformModel Line-up and SpecificationsCommon specificationsOutput RipplePower source fluctuationLoad fluctuation Size Weight InputCV CC Model name CVCCCVCC CVCC Type (Approx.)V oltage*PowerconsunptionVAmVrms mArms 0.005%+mVmA0.005%+mVmAkgVApprox.kV A 0 to 10PAN 16-10A 0.5211130111000.40 to 160 to 18PAN 16-18A 0.551113I 2171000.80 to 30PAN 16-30A 0.551323I 323100 1.10 to 50PAN 16-50A 0.5101325II 36100 1.60 to 5PAN 35-5A 0.5111120111000.40 to 350 to 10PAN 35-10A 0.521113I 2171000.80 to 20PAN 35-20A 0.531323I 323100 1.40 to 30PAN 35-30A 0.551315II 36100 1.80 to 3PAN 60-3A 0.5111120111000.350 to 600 to 6PAN 60-6A 0.521113I 2171000.70 to 10PAN 60-10A 0.531323I 322100 1.10 to 20PAN 60-20A 0.521112II 35100 2.10 to 2.5PAN 70-2.5A 0.5111110111000.350 to 700 to 5PAN 70-5A 0.521112I 2171000.80 to 8PAN 70-8A 121113I 322100 1.10 to 15PAN 70-15A 151113II 35100 1.90 to 1.5PAN 110-1.5A 0.5111110111000.40 to 1100 to 3PAN 110-3A 0.511112I 2171000.70 to 5PAN 110-5A 111112I 322100 1.00 to 10PAN 110-10A 121113II 35100 2.00 to 1PAN 160-1A 1111110111000.330 to 1600 to 2PAN 160-2A 111112I 2171000.70 to 3.5PAN 160-3.5A 111122I 322100 1.00 to 7PAN 160-7A 121122II 36100 1.90 to 2500 to 2.5PAN 250-2.5A 522131I 323100 1.10 to 4.5PAN 250-4.5A 522132II 35100 1.80 to 3500 to 3.5PAN 350-3.5A 121112II 36100 2.10 to 6000 to 2PAN 600-2A10.50.002%+10.50.002%+11II371002.0*:Input voltage : 110, 120, 200, 220, 230 and 240V AC input are available at request.Constant voltage100 p.p.m./°C (standard value)temperature coefficient Constant current300 p.p.m./°C (standard value)temperature coefficient Transient response time50µs: Time required for the output voltage to return to a value less than 0.05% of the rated value + 10 mV , against a fluctuation of 5% to 100% of the output current.Ripple noiseUsing an AC voltmeter having a range of 5 Hz to 1 MHz, ±3dB, indicated in mean value and effective value measurement is performed with either a positive or negative output terminal con-nected to the ground.Indication metersV oltmeter indication error ±(0.5% rdg + 2 digits) at 23°C ±5°C V oltmeter max. indication digits 199.9 (Note: 19.99 for the PAN16-10A/PAN16-18A/PAN16-30A/PAN16-50A models,and 1999 for the PAN250-2.5A/PAN250-4.5A/PAN600-2A)Amperemeter indication error ±(1% rdg + 5 digits) at 23°C ±5°CAmperemeter max. indication digits 19.99 (Note: 1.999 for the PAN110-1.5A/PAN160-1A, and 199.9 for the PAN16-30A/PAN16-50A/PAN35-20A/PAN35-30A/PAN60-20A)Grounding Either the positive or negative terminal can begrounded.Isolation voltage to ground ±250 VDC (However, ±500 VDC for thePAN110-1.5A/PAN110-3A/PAN110-5A/PAN110-10A/PAN160-1A/PAN160-2A/PAN160-3.5A/PAN250-2.5A/PAN250-4.5A.±1000 VDC for thePAN600-2A.)Insulation resistance Across input side and chassis: Greater than 30M Ω at 500 VDCAcross output side and chassis: Greater than 20M Ω at 500 VDC(For PAN350-3.5A and PAN600-2A, this is 1000V DC, 20 M Ω, or higher.)Withstand voltage Nothing abnormal should occur at 1500 V AC,1 min.Operating temperature 0 to 40°Operating humidity 10 to 90% RH Cooling system Forced air cooling using a fan Constant voltage operation Green LED Constant current operation Red LED Protection system q Constant voltage/current automatic crossoversystemq Overvoltage protector (OVP)(10% to 110% of rated output voltage)q Overcurrent protection circuit(Approx. 110% of rated output current)q Overvoltage protection circuit(Smoothing electrolytic capacitor for the rec tification circuit)q Overheat protection circuit (OHP)(Semiconductor cooling heat-sink [100°C])q Thermal fuse(Main- or sub-transformer)l Input/output fuse。