Application of thyristor controlled phase shifting transformer excitation impedance switching control to suppress short-circuit fault current level

Short-circuit fault current suppression is a very important issue in modern large-interconnected power networks. Conventional short-circuit current limiters, such as superconducting fault current limiters, have to increase additional equipment investments. Fast power electronics controlled flexible AC transmission system(FACTS)devices have opened a new way for suppressing the fault current levels, while maintaining their normal functionalities for steady-state and transient power system operation and control. Thyristor controlled phase shifting transformer(TCPST) is a beneficial FACTS device in modern power systems, which is capable of regulating regional powerflow. The mathematical model for TCPST under different operation modes is firstly investigated in this study. Intuitively, the phase shifting angle control can adjust the equivalent impedance of TCPST, but the effect has been demonstrated to be weak. Therefore, a novel transformer excitation impedance switching(EIS) control method, is proposed for fault current suppressing, according to the impedance characteristics of TCPST. Simulation results on IEEE 14-bus system have shown considerable current limiting characteristic of the EIS control under various fault types. Also, analysis of the timing requirement during fault interruption, overvoltage phenomenon, and ancillary mechanical support issues during EIS control is discussed,so as to implement the proposed EIS control properly for fast fault current suppression.

基于最优潮流并计及TCPST的可用输电能力计算

基于最优潮流(OPF)方法,将可用输电能力的计算转化为求解多约束的非线性规划问题,建立了计及晶闸管控制的移相器(TCPST)的ATC计算模型,利用功率注入法将TCPST对电网的控制作用通过对相关节点的等效注入功率来体现,从而使与TCPST关联的节电导纳矩阵由非对称阵变为对称阵,进而大大简化了潮流计算程序。在算法上采用半光滑牛顿算法,IEEE30节点系统的计算结果表明,所提出的模型及算法正确。

基于改进MCCIPM的含TCPST电力系统最优潮流计算

随着可控移相器(TCPST)在现代电力系统中应用水平的逐渐提高,计及TCPST的系统最优潮流(OPF)计算迎来了新的挑战。文中提出了一种基于改进内点法的含TCPST电力系统OPF计算方法。首先,结合TCPST接入系统的等效功率注入模型,以系统有功网损最小为目标建立含TCPST的最优潮流模型;其次,为提高收敛速度,文中针对多中心-校正内点法(MCCIPM)进行改进,提高了仿射方向迭代步长并重新配置关键映射参数;最后,基于改进后的MCCIPM,在IEEE 14、IEEE 30和IEEE 118节点网络完成OPF计算。测试结果表明,TCPST具有控制线路潮流分布的能力,验证了文中计算方法在求解效率上的优越性。

Comparative Analysis of Hybrid Controllers of Done Systems (UPFC) and Interphase Power Regulators Type RPI 30p15 on Contingency Management in Electrical Networks

The aim of this work is to demonstrate that interphase power regulators (IPR) bring new and interesting ultra-solutions that complement those already taken into account by the FACTS (Flexible Alternative Transmission System) in the resolution of the problems related to the power flow in the AC transmission networks. In order to facilitate the understanding of this work, a comparative study of the performances of the two technologies between the UPFC (Unified Power Flow Controller) and RPI was carried out and at the end of which we were able to highlight the preponderance of RPI compared to the UPFC in the bypassing of the short-circuit fault insofar as the latter allows, in particular, an increase in the transformation capacity without an increase in the level of the short-circuit. The decoupled watt-var method has been used to control the UPFC while the RPI is controlled by phase shift. The simulation results are obtained in the Matlab Simulink environment and show the flexibility of the RPI compared to the UPFC in limiting strong contingencies.

可控移相器研究现状及其发展前景

随着电力电子技术的发展及其在FACTS设备中的应用,可控移相器(Thyristor Controlled Phase Shifting Transformer,TCPST)显示了良好的应用前景,它不仅具有传统机械式移相器(PST)控制潮流的作用,而且由于电力电子器件响应速度快的特点,使其具有阻尼振荡,提高暂态稳定等特点。介绍了可控移相器的原理,功能,并对已存在的可控移相器拓扑结构进行分类,并在此基础上浅谈可控移相器的发展前景。

含可控移相器的电力系统潮流分析

可控移相器（TCPST）是一种重要的FACTS装置，其可以实现对电力系统潮流的调控。本文综合考虑了TCPST对系统潮流计算的影响。提出了一个简单，有效的含TCPST的电力系统潮流计算方法，其特点可以很方便地与现有的交流潮流算法相结合。算例验证所提出的方法是正确有效的。