基于级联有源滤波器与静止无功补偿器的综合补偿控制方案

级联多电平有源滤波器(CS-APF)与静止无功补偿器(SVC)同时运行存在稳定性及无功补偿控制优化等问题。文中提出一种统一控制策略,结合SVC和CS-APF的功能特点,使SVC对负载正序无功分量及负序分量的补偿进行前馈控制和电网电纳(不包含CS-APF分量)反馈控制;CS-APF对晶闸管相控电抗器(TCR)与电网负载谐波的补偿进行前馈控制,并去除SVC中固定电容分量,进行电网电流反馈控制,同时对SVC无功补偿进行二次优化补偿。另外,提出一种TCR谐波电流预计算方法,根据TCR触发角当前值与电网电压锁相环相位,构建TCR谐波电流,实现对TCR谐波的预计算。仿真和实验研究表明,在该综合控制方案下,SVC与CS-APF控制不存在闭环,系统稳定性高,TCR谐波补偿无滞后,无功补偿响应较快,补偿能力强。     

无功和谐波补偿装置的控制方法

针对具有功率因数补偿、补偿负载不平衡和滤除电网谐波电流等功能的联合运行系统,提出一种新的控制方法,由SVC模式控制和APF控制2部分组成.其中,SVC模式控制通过负序基波提取器实现电网负序基波分量的检测;通过改进的电压控制器实现公共连接点的电压稳定.利用特定次数谐波检测并进行相位补偿的方法实现电网谐波分量的检测;利用神...     

基于瞬时无功理论的SVC抑制次同步振荡的附加控制设计

HVDC解决了长距离输电中电压降低、线损加大、无功补偿等问题,却又给系统带来了次同步振荡的危险。SVC在补偿HVDC无功功率需求的同时也可以通过增加附加控制来抑制可能产生的次同步振荡。为了使SVC的补偿精确,SVC附加控制的输入信号取易于获得的电压电流信号且有明显的抑制效果,将采用基于瞬时无功理论的方法来设计SVC的控制,消除不对称分量和其他频率下谐波分量的影响,使得控制效果更精准。以向上直流降功率25%单极孤岛运行方式为例,验证了基于瞬时无功理论设计的SVC控制对次同步振荡抑制的有效性。     

带辅助控制的TCR型SVC控制策略研究

针对TCR型SVC稳态运行时为了维持电压稳定需要不断调整输出而造成损耗较多的问题,在基本电压控制策略中加入了电压死区辅助控制:在电压允许误差范围内锁定SVC,在范围外则释放SVC调节电压至范围内.在此基础上,为了能更有效地利用SVC有限的额定容量,对应设计了可根据电压大小而变化的电压参考值,确保SVC输出一直处于可调节范围内且可具有较多的无功储备.针对当系统中含有2次谐波电压分量时会导致TCR电流中产生大量的直流分量问题,加入了TCR平衡辅助控制:通过将快速傅里叶变换和PI调节相结合调制触发角使反并联的晶闸管达到在正方向和负方向的导通时间不相同,将直流电流分量减小到零,保证装置的安全运行.仿真结果表明上述辅助控制具有可行性和有效性.     

采用SVC抑制次同步谐振的机理分析

针对采用静止无功补偿器（SVC）抑制次同步谐振（SSR）的核心问题,即如何提供与扭振模态频率互补的电流分量问题,提出了SVC基波电纳次同步调制的控制机理和数学模型。分析表明:对SVC基波电纳参考值进行次同步频率调制,可控制其输出大小和相位适当的模态互补频率电流,进而在机组中产生对应模态的阻尼扭矩,达到抑制SSR的目的。这一控制机理同时会导致SVC输出超同步和复杂分数次谐波分量。基于详细电力电子电路的非线性电磁仿真和实际SVC设备试验均验证了控制机理和数学模型的有效性和正确性,进一步将所提出的控制机理应用于锦界电厂串补输电系统的SSR问题,数值仿真结果证实了其有效性。     

神朔电铁负荷和谐波对电网影响的治理

当电铁110kV供电线路运行时,神木电网负序和谐波超过相应国标要求,并影响2×100 MW发电机等的正常运行,提出了一个静止无功补偿(SVC)方案,用以抑制负序和谐波电流。使用按照部分平衡负序分量来计算SVC容量和参数的新计算方法,发展了一种按部分平衡负序的SVC控制策略,并用于SVC控制,于2002年经过现场调试和投入运行,现场测量数据表明,SVC抑制负序和谐波的效果,达到了预期的要求。     

SVC和APF联合系统的研究

提出了静止无功补偿器(SVC)和有源电力滤波器(APF)联合运行进行无功补偿和谐波治理的方案;介绍了系统的拓扑结构、分析了系统的稳定性,指出当APF采用"只检测特定次谐波电流"的检测方法时,其与SVC的耦合程度小,系统能稳定运行.在此基础上,研究了一种适用于APF的k次谐波电流检测方法,并深入分析了SVC和APF的控制策略.样机实验结果验证了k次谐波电流检测方法和控制策略的有效性和正确性.     

交流电弧炉SVC装置2次滤波支路设计校核新方法

交流电弧炉不仅属于典型的谐波污染源、闪变发生源,而且交流电弧炉冶炼过程在2次附近产生较大的间谐波分量。基于某实际钢铁公司交流电弧炉谐波发生量和SVC装置参数的定量分析及仿真研究,得到交流电弧炉必须设置2次C型滤波器,保证将电弧炉2次左右的谐波和间谐波放大控制在一定范围内的研究结论。在此基础上给出2次滤波支路的设计方法,提出了2次滤波支路安全校核新方法,指导交流电弧炉滤波装置工程设计。     

电气化铁路中SVC负序补偿应用技术研究

随着电气化铁路的迅速发展,电铁牵引负荷产生的负序分量及高次谐波,除对牵引供电系统造成危害外,还会造成电力系统负序及谐波污染[1],因而,电铁的负序及谐波危害已成为制约我国电气化铁路发展的重要因素。结合电气化铁路给电网带来的影响,着重探讨电铁负序补偿中SVC的使用问题。根据国外一些发达国家如日本、澳大利亚等国成功将SVC技术应用在电气化铁路的无功和负序补偿案例以及国内SVC负序补偿应用实例,对SVC负序补偿原理及运行方式进行了研究分析,对SVC在电铁负序治理中的应用前景做了初步探讨,以期提高电力系统运行的     

电炉SVC系统优化方案滤波性能分析

针对现场SVC系统存在的谐波超标问题,对提出的SVC优化系统进行了理论分析。选定的混合有源滤波器控制方式可使混合滤波器对2~5次、7次谐波以及高次谐波进行谐波抑制。稳态仿真分析结果很好地证明了优化系统稳态滤波效果。     

基于静止无功补偿的电铁谐波抑制分析

电铁110 kV线路运行时,电网负序和谐波超过国标要求,并影响发电机组的正常运行,提出了一个静止无功补偿方案,来抑制负序和谐波电流。对静止无功补偿器的性能进行了分析,研究了其工作原理和性能表现。针对电铁谐波的严重危害,论述了将其投入到电铁谐波治理所收到的良好效果,并简要分析了静止无功补偿器对电力系统稳定性的作用及影响。     

A graphical method to determine the harmonic magnification in radial feeders due to SVC operation

Static var compensators (SVC) are used widely in power systems. Their disadvantages are the harmonic generation and, under certain operating conditions, SVC interacts with the power system. This interaction may magnify some of the harmonic components. This paper represents a graphical method that explores the effect of SVC's parameters and operating point on the voltage quality at load's bus bar due to the harmonic component magnification. This method overcomes the need to solve the system's non-linear state equations and/or the use of EMTP program to investigate the possibility of harmonic magnification occurrence in a particular radial feeder. The method also determines the critical value of SVC inductance to avoid harmonic magnification. The method is applied to a radial feeder in the state of Massachusetts, USA. The results are reported with a comparison to EMTP results.     

Design considerations for the Eddy County static VAr compensator

This paper describes the steps for the design of the static VAr compensator at (SVC) Eddy County. The specified system requirements on operating range, loss evaluation and harmonic performance led to an SVC configuration which contains one thyristor switched capacitor (TSC) branch, one thyristor controlled reactor (TCR) branch for continuous reactive power control and two double tuned filter branches. The system voltage of the SVC secondary bus was optimized to 8.5 kV based on thyristor equipment capabilities. The paper shows the voltage and current stresses of the thyristor valves taking into account system faults for the TCR branch and misfiring effects on the TSC branch. The approach for filter design considering the harmonic performance requirements and resulting component ratings are shown. The Eddy County SVC commenced commercial operation in April 1992     

Reactive current control through SVC for load power factor correction

This paper discusses a new technique for controlling SVCs (Fixed Capacitor–Thyristor Controlled Reactor) in power systems with the aim of canceling the reactive current component of the load. A complete model of the SVC with its control circuit is set up and simulated in the EMTDC program. The generated harmonics from the proposed SVC controller are considered to design simple tuned filters to cancel the undesirable harmonic components. The effect of these filters is considered as well in the SVC control design, so that the reactive current component absorbed by the combination of the load, SVC, and filters is eliminated. The proposed control technique is compared with respect to a standard PI-based SVC controller.     

静止无功补偿成套装置晶闸管阀组

随着国民经济的发展和现代化技术的进步,电网负荷急剧增大,对电网无功功率的要求与日俱增。由于高压晶闸管制造技术日趋成熟,绝大部分用户采用TCR+FC型静止无功补偿器(Static Var Compensator,简称SVC)来改善电网电能质量。介绍了TCR+FC型SVC这种动态无功补偿及滤波装置的原理和TCR阀各部分的主要功能。其技术效果显示SVC是一种可自动调节的无功功率补偿装置,具有抑制电压波动,改善功率因数和吸收电网谐波功能。     

The stability of voltage oscillation modes in longitudinal power systems with SVC

In this paper, we investigate the stability of voltage oscillation modes in longitudinal power systems equipped with static var compensators (SVC). These modes are usually stable, so they do not appear without external force. The conventional harmonic resonance is a phenomenon in which an oscillation mode is excited with a harmonic source. Hence, it is solved by removing the source with a harmonic filter. For this reason, an SVC is equipped with several filters. However, there is a possibility that an oscillation mode itself may become unstable. If a mode is unstable, it can have a large amplitude without any harmonic source. Since it needs no harmonic source, its frequency is not limited to a harmonic frequency, but can have any value. The harmonic instability in direct‐current transmission systems is an example of such phenomena. The PLL (phase‐locked loop) is considered to be effective to suppress harmonic instability with an SVC. However, no theoretical reason has been shown as yet. This paper clarifies the effectiveness of PLL based on a stability condition for the voltage oscillation modes. Frequency responses of a thyristor‐controlled reactor (TCR), a component of the SVC, are largely influenced by the presence of the PLL. If a PLL exists, the stability condition is always satisfied, and all modes are stable. Lastly, we perform numerical simulations to show the validity of our investigation. © 2001 Scripta Technica, Electr Eng Jpn, 137(2): 8–17, 2001     

鞍山红一变SVC国产化示范工程介绍

鞍山红一变高压静止无功补偿装置(static var compensator,SVC)工程是中国第一个电网SVC国产化示范工程。SVC主要用来替代变电站原有调相机,投运后不仅能为鞍山电网提供快速动态无功电源,还能提高电网稳定性和电能质量。文章阐述了该工程的设计、运行、应用方面的主要问题,介绍了SVC容量的确定、系统主接线、技术参数,论述了装设SVC后的谐波分析结果和电压改善仿真结果以及SVC装置投运后对电网电压和谐波的实际改善效果,分析了SVC所带来的经济效益、对系统潮流分布的改善,鞍山受电断面稳定水平的提高。     

静止无功补偿器与有源电力滤波器联合运行系统

提出一种具有功率因数校正、补偿负载不平衡和滤除电网谐波电流的静止无功补偿器(static var compensator,SVC)和有源电力滤波器(active power filter,APF)联合运行系统电路结构。其中,SVC由晶闸管控制电抗器(thyristor controlled reactor,TCR)及固定电容器(fastness capacitor,FC)组成,主要用来快速补偿无功,并通过对其三相不对称控制来消除电网三相不对称和负序电流;APF部分主要用来消除电网及SVC引起的谐波电流,同时抑制固定电容器与电网等效阻抗间可能的串并联谐振。在分析SVC和APF联合运行系统基本工作原理的基础上,对联合运行时的控制方法进行研究。仿真和实验结果证明了该联合运行系统的可行性。