TCSC运行原理及其在电网中的工程应用

可控串联补偿(TCSC)是柔性交流输电装置的典型代表,基于适当的控制策略TCSC能快速连续地调节输电线路电抗,减小因功率输送引起的电压降和功角差,提高线路输送能力和电力系统的稳定性.为使工程技术人员更好地掌握TCSC技术,主要分析TCSC的运行原理,在此基础上给出了TCSC在现代电网中的工程应用情况.     

电网可靠性对可控串联补偿部件参数的灵敏度分解算法

可控串联补偿器(TCSC)是一种常见的柔性输电设备,多用于改善输电能力。现有TCSC对其电容器组、电抗器等部件的可靠性建模较为粗略,因此无法直接描述部件可靠性对电网可靠性的影响。考虑部件故障模式,提出TCSC可靠性分层等值算法,建立含TCSC线路可靠性状态空间模型。基于改进频率和持续时间(FD)算法,求解串联补偿线路状态概率和转移率,及其对部件可靠性参数的灵敏度。联立电网可靠性对串联补偿线路可靠性、串联补偿线路可靠性对TCSC部件灵敏度,提出电网可靠性对TCSC部件参数的灵敏度分解算法。算例分析验证了算法的可行性和正确性,有助于从电网角度发现和改善柔性交流输电设备的薄弱环节。     

TCSC数学模型和控制技术研究综述

随着电网的不断发展,高电压、远距离和大规模互联电网将是必然的发展趋势。可控串联补偿(TCSC)作为柔性交流输电系统(FACTS)的重要组成部分,是未来输电系统的支撑技术,在电力系统中的作用越来越重要。首先介绍了TCSC的基本原理和特点,然后从数学模型和控制方式两方面综述了TCSC研究的主要成果,最后总结了国内外的应用现状,并提出了一些存在的问题和对进一步研究的方向进行了展望。     

考虑FACTS及成本的输电阻塞管理方法

在开放的电力市场中,阻塞管理方法及阻塞成本的研究具有非常重要的理论和实用价值.利用柔性交流输电设备(FACTS)可以提高系统输电能力的特点,综合考虑了系统物理特性和经济特性,提出了结合灵敏度分析方法和系统最小阻塞管理成本的阻塞管理方法.首先建立了考虑确定晶闸管控制的串联电容器(TCSC)的线路模型;然后根据线路无功功率损耗灵敏度法和有功功率分布灵敏度法计算各线路的灵敏度系数,寻找方法对应的TCSC的安装线路;最后以系统阻塞管理成本最小为目标函数,确定TCSC的最优安装线路以及解决阻塞问题的方法.6节点系统的仿真分析结果验证了算法的有效性.     

可控串补基波阻抗数值算法及仿真研究

可控串联补偿技术不仅可以提高输电线路的输送容量、改善电网的潮流分布、增强系统的暂态稳定性,而且还可以抑制低频功率振荡和次同步谐振等.该研究对TCSC的基本结构及运行原理进行了介绍,通过求取TCSC回路中各电压电流,建立TCSC的数学模型,并进行谐振点分析,利用Matlab软件进行数值仿真计算,最后得到TCSC的基波阻抗...     

含TCSC与不含TCSC的远距离高压交流输电线路中CSR自控参数整定值的比较

给出一种同时含TCSC与CSR元件的远距离高压交流输电线路的构想,建立了非常实用的CSR元件自控模型.针对含与不含TCSC的远距离高压交流输电线路,利用MATLAB-Simulink仿真研究比较2种输电线路中CSR元件自控参数整定值的差异,说明了含TCSC元件的远距离高压交流输电线路中CSR元件自控参数整定的特殊性.     

基于能量函数及PID算法的TCSC控制策略

可控串联补偿TCSC可以连续调节输电线路的阻抗、阻尼系统的振荡,提高系统暂态稳定性.首先,采用暂态能量函数TEF值对系统稳定性进行量化,推导出仅含支路信息的TEF对时间的导数表达式,以导数值最小为目标,制定系统中支路的TCSC装置控制策略.在此基础上,加入PID连续控制方式,提高TCSC的控制精度,精准调节TCSC对线路电抗的补偿值达到控制策略所得阻抗值.最后,在单机无穷大系统上进行仿真验证.结果表明:提高TCSC控制精度能够有效避免系统在大扰动后发电机首摆失稳,并能提高振荡收敛速度.推广至多机系统,仿真结果表明:该控制策略同样具有优越性.     

基于TCSC的优化阻塞模型设计与应用研究

针对柔性交流输电装置控制线路潮流的特点,在传统OPF的基础上,将调整网络参数与经济调度方法相结合.研究了计及TCSC的优化阻塞调度模型.求解过程中,把TCSC对系统的调节作用表述成节点附加功率的形式.并将TCSC控制参数纳入变量空间内寻优.IEEE5系统的仿真结果验证了该方法的有效性.     

特高压输电线路用新型TCSC方案及其控制策略研究

为了在1 000 kV特高压输电线路或有较大额定电流的750 kV输电线路上加装可控串补(thyristor controlledseries compensation,TCSC),解决目前TCSC中所需晶闸管阀通流能力不足的问题,提出了一种基于双阀控电抗器(thyristor controlled reactance,TCR)支路并联的TCSC实现方案,并对其控制策略进行了研究。通过对幅值相等控制策略下双TCR支路TCSC进行数学建模,设计了相应的阻抗控制环节和幅值相等控制环节,实现了相应的控制目标。仿真结果表明,提出的TCSC实现方案及其控制策略可行,适用于工程应用。     

基于小波包变换的暂态保护在带TCSC输电线路中的应用

可控串补技术(TCSC)是柔性交流输电(FACTS)技术中的一项重要技术.本文分析了TCSC装置自身的特点和对传统线路保护的影响,提出了一种基于小波包变换的暂态保护新方案.该方案利用小波包变换来提取暂态信号中的多个频段的谱能量来实现区内外故障的识别.Matlab仿真结果表明,该方案应用于TCSC输电线路在各种故障条件下是可行的.     

多可控串补自适应协调控制设计

采用多可控串联补偿器（thyristor controlled series compensation,TCSC）联合运行可提高线路功率传输能力,但多TCSC联合运行时所存在的交互影响可能导致系统暂态稳定性下降。设计一种新的自适应控制方案,动态自适应调整多个TCSC联合运行时的参数,以规避多TCSC的负交互影响。利用能量函数分析多TCSC协调控制规律,然后通过微分观测器引入微分信号,再将专家控制和神经网络引入自适应控制,动态调整PID（proportion integral differential）参数。通过在一个装设2台TCSC的4机2区域系统的仿真验证,并和PI控制、BP-PI控制进行对比,结果表明,所设计的自适应控制器在提高系统暂态稳定性方面,具有一定的优越性。     

A study of thyristor controlled series capacitor models for power system stability analysis

The thyristor‐controlled series capacitor (TCSC) is promising as a powerful device to increase power transfer capability and transient stability. The basic configuration of the TCSC consists of a series of capacitors connected antiparallel with thyristor‐controlled reactors, so that firing angle control of the thyristors makes the TCSC capable of achieving impedance control in a wide range with quick response. It is important to clarify the relationship between the fundamental reactance of the TCSC and the firing angle of the thyristors, thus leading to practical applications of the TCSC for enhancement of power transfer capability and transient stability in transmission lines. Two relationship equations for the TCSC's fundamental reactance have already been proposed. One is the relationship equation derived from a TCSC circuit whose source is a voltage. The other is the relationship equation derived from a TCSC circuit whose source is a current. For TCSC installed in a transmission line, it is clear which equation is more adequate for analyzing power system stability. In this paper, the authors determine whether either of the equations is valid for analyzing a power system stability.

• 1. In the steady state, the TCSC fundamental reactance is analyzed and compared with the two equations and EMTP. It is clear that the TCSC reactance based on current source is adequate.
• 2. The swing angle of a generator when the firing angle is stepped up is analyzed with EMTP and an analytical model using the TCSC model based on current source. It is shown that the proposed model is effective for power system stability analysis. © 1999 Scripta Technica, Electr Eng Jpn, 129(1): 20–28, 1999

     

用TCSC提高西北电网暂态稳定极限的研究

就西北电网西电东送问题中可控串联补偿的应用效果做了仿真研究；介绍了晶闸管可控串联补偿(TCSC)的结构及运行方式、稳态和暂态数学模型。通过大量仿真计算的结果对比，给出了关于TCSC安装位置、容量、控制器结构及其参数取值的建议。仿真计算表明，采用TCSC能大幅度提高西北电网西电东送的能力，是根本解决西电东送瓶颈问题的一种可行的方法。本文所采用的控制策略对提高系统的暂态稳定性效果非常明显。     

A nonlinear control for coordinating TCSC and generator excitation to enhance the transient stability of long transmission systems

The transient stability of a long transmission system can be significantly influenced by the action of excitation systems and any TCSC controls installed. This paper presents a coordinated control scheme for excitation systems and TCSC controls for improving the stability of a transmission system, where a power plant is connected with a power grid through long transmission lines. Based on the TCSC equivalent reactance and the modulated active power, a control law for the TCSC is deduced associated with the control law of the excitation system on nonlinear basis. The proposed control scheme is developed upon nonlinear optimal-variable-aim strategies (OVAS). With two pre-selected aims to be achieved during first swings following a fault and in sequent dynamic ranges, coordinated actions of the TCSC and excitation system can be an effective means of enhancing transient stability and damping subsequent oscillations. The effectiveness and robustness of OVAS-based controls are demonstrated with a one-machine system, where the simulations are carried out by the NETOMAC program system. In comparison with a conventional control scheme, significant improvements in dynamic performance of the test system are achieved by the proposed control strategy.     

成碧线220 kV可控串补系统的控制策略和系统试验

采用可控串联补偿（TCSC）可以提高长距离弱联系系统的电网输送能力、阻尼系统低频振荡、提高系统稳定性。合理的控制策略能使TCSC产生更有效的作用。成碧线220 kV的TCSC系统控制策略主要针对电力系统的暂态稳定和阻尼振荡2个阶段进行设计,其控制器主要由阻抗控制环节、阻尼控制环节、暂态稳定控制环节以及保护环节、延时环节组成。系统试验证明:成碧线220 kV的TCSC装置能够平滑、快速地进行阻抗调节,有效阻尼系统低频振荡,提高系统稳定性。     

提高暂态稳定的励磁与FACTS协调策略设计

灵活交流输电系统(FACTS)元件及发电机励磁系统对远距离输电系统的暂态稳定性有很大的影响。该文针对单机远距离与电网互联系统，提出采用非线性最优变目标策略协调设计发电机励磁、可控串补（TCSC）和静止无功补偿器(SVC)，从而提高首摆稳定性及快速阻尼后续振荡。所提协调方案是基于TCSC在故障期间闭锁时，SVC作为TCSC的辅助控制手段，当故障清除后，立即投入TCSC，从而使TCSC、SVC与发电机励磁同时贡献于暂态稳定性。在整个过程中，采用非线性最优变目标控制策略来协调所有控制器，即在暂态稳定第一摆及后续动态过程中预先设定两个目标：其一是励磁与FACTS输出最大，从而保证系统最大的暂态稳定域；其二是当发电机滑差接近于零时，控制器以阻尼功率振荡为目标，以使系统迅速恢复至稳态。最后采用NETOMAC仿真软件在我国阳城—淮阴输电工程中进行了仿真，并与常规PID控制进行了比较。结果表明，所提策略是正确的，有效的。     

基于无源控制方法的TCSC控制器及其仿真研究

简要介绍了一类基于无源系统理论的最优控制方法－PBC方法，基于该方法设计了晶闸管控制的串联补偿器（TCSC）无源控制器，由于该控制器中的变量均可实现本地测量，故使其能有效地应用于实际电力系统中，针对川渝电力系统的仿真结果，证明了基于PBC控制器的TCSC可以有效地提高系统的暂态稳定性和传输功率。     

Computation of TCSC reactance and suggesting criterion of its location for ATC improvement

Deregulation of power system has brought major changes in the system operation and control. When open access is made available to the market players, one or more lines in the transmission network could be overloaded, thereby causing congestion. Congestion management can be achieved by improving available transfer capability (ATC) of the network. FACTS devices such as TCSC and UPFC have proven their utility for ATC improvement. The active power flow control can be done more effectively by these devices. Their design and installation need the determination of changes in parameters for maintaining the desired power flow in the line causing congestion. This paper proposes a new approach for determination of changes in the reactance of TCSC, required for achieving the desired transfer capability. Sensitivity analysis is used for computing the changes in line flow of the lines with and without TCSC. Also a suitable criterion with a mathematical model for computation of reactance is proposed for selection of a line for the installation of TCSC. Through the results, it is shown that ATC is improved to a specified value by the installation of TCSC in the selected line which has the reactance as computed by the proposed method.     

Transmision capability enhancement using power electronics technologies for the future power system in Japan

Many power system stabilization measures realized by the upgrading transmission lines, generator controls, and power system controls and protections have been developed and utilized toward increasing transmission capability of power systems in Japan. With restriction of transmission routes and power system deregulation, it is now inevitable that transmission capability will be increased to sustain such power system reliability. Various remarkable power electronic technologies such as self-commutated SVC are being introduced toward improving power system stability. It is expected that these will also be employed in power flow control to avoid faults from cascading throughout the entire power system. This paper describes the present researches related to the application of power electronics to power systems in CRIEPI, including the recent results of the research carried out in cooperation with ten Electric Power Companies subsidized by MITI. Specifically: (1) analytical studies in power system enhancement by self-commutated SVC, thyrister controlled series capacitance (TCSC), and unified power flow controller (UPFC); (2) analytical studies on transmission capability increase of the interconnected power system applying the HVDC system with self-commutated converters; and (3) experimental studies of the self-commutated converter for continuous operation of converters at AC system faults.