POWER FLOW CONTROL OF POWER SYSTEMS BY THYRISTOR-CONTROLLED SERIES CAPACITOR

可控串联电容器（TCSC）是柔性交流输电系统（FACTS）控制器之一，它能更好地利用现有输电设备，实现灵活的潮流控制，提高稳定性，增加输电能力。然而，由于运行经验较少，因此对TCSC的运行和特性的进一步了解仍有待于探索。本文主要研究了开放接入条件下TCSC的稳定性改善和最大限度利用输电网的优化运行两个问题，主要研究成果如下：（1）TCSC稳定电力系统利用TCSC数学模型对控制TCSC的触发角来稳定电力系统进行了仿真研究。研究系统是一台连接到无限总线系统的单机。TCSC控制与现有电力系统控制器（如AVR h）的相互作用 ...更多信息 如被调查。结果表明，如果不采用TCSC和AVR的协调控制，系统的阻尼将减小。结果表明，TCSC的三相点火角单独控制对不对称故障是有效的。文中还讨论了TCSC电路附加电阻对稳定性的影响。(2)粒子群算法在潮流控制中的应用，以最大限度地接受所需的轮式功率。电力传输网络的开放访问已经进行，以促进发电竞争和客户的选择。当多个PPS请求同时向客户供电时，期望输电网络接受尽可能多的请求功率。可以通过使用TCSC控制功率流来最大化总请求功率。在这项研究中，基于粒子群优化（PSO）算法已被提出来确定TCSC的最佳电抗。所提出的方法的有效性已被成功地检查为6和IEEE 30节点系统模型。少

The thyristor-controlled series capacitors (TCSC), one of the FACTS (Flexible AC Transmission Systems) controllers, are expected to provide better use of existing transmission facilities, such as flexible control of power flow, stability improvement, and an increase of power transfer capability. However, there has been little operating experience and thus further understanding of the operation and characteristics of TCSC is still to be sought. This study focuses on the following two subjects : (1) stability improvement and (2) optimal operation of TCSC for maximum use of transmission under open access era.Results obtained in this study are summarized as follows :(1) Power system stabilization by TCSC.Simulation using TCSC mathematical model have been conducted on power system stabilization by controlling the firing angle of TCSC. The study system is a one-machine connected to an infinite-bus system. Interaction between TCSC control and the existing power system controller such as AVR h … More as been investigated. It was found that without coordinate control of TCSC and AVR there has been less damping in the system. It has been made clear that individual control of three-phase firing angles of TCSC is effective for unsymmetrical line faults. Effects of additional resistor to TCSC circuit upon stabilization have been also discussed.(2) Application of PSO to power flow control for maximum acceptance of requested wheeled power.Open access to power transmission networks has been carried out to foster generation competition and customer choice. When several PPSs request to simultaneously supply power to customers, it is expected that transmission network accepts as much requested power as possible. It is possible to maximize total requested power by controlling power flow using TCSC. In this study, an algorithm based on Particle Swarm Optimization (PSO) has been proposed to determine the optimal reactance of TCSC. The validity of the proposed method has been checked successfully for 6 and IEEE 30 bus system models. Less