采用SVC抑制发电机次同步谐振的理论与实践

针对静止无功补偿器(SVC)在抑制次同步谐振(SSR)方面的理论与应用进行了研究。分析了SVC抑制SSR的基本工作原理;提出了SVC抑制SSR的各种控制策略;讨论了SVC的容量估计方法。以托克托工程为背景分析了SVC抑制SSR的效果。仿真结果表明SVC能有效抑制SSR的发生,为解决国内交流串补输电工程中SSR问题提供了参考,也为SVC装置的更好应用提供了依据。

Theory and Experiences of SVC for Damping Subsynchronous Resonance

Both the theory and the experiences of Static Var Compensator for damping the subsynchronous resonance are investigated in this paper. Firstly,the basic operation principle of the static var compensator to damp the subsynchronous resonance is analyzed.The major component of the static var compensator for damping the subsynchronous resonance usually consists of a deltaconnected three-phase thyristor-controlled reactor.The analysis of the principle shows that damp of the subsynchronous resonance can be achieved by modulating the reactive current in the thyristor-controlled reactors.Then,based on the basic principle,various control strategies of the static var compensator for damping the subcynchronous resonance,such as the proportional controller,the modal control technique and the voltage controller etc,are presented respectively.And the structure of each type of controller is shown in detail.Further,a method of estimating the size of the static var compensator is introduced and a corresponding example based on the IEEE first benchmark model is also presented.Secondly,based on the Tuoketuo power plant,the effects of the static var compensator on damping the subsynchronous resonance are simulated and analyzed in time domain by the program PSCAD/EMTDC.And the simulation results show that the static var compensator can damp the subsynchronous resonance effectively with a simple proportional controller.The results are helpful to solving the subsynchronous resonance problems which exist in the series compensated transmission systems in China.And the conclusions also provide valuable references for better applications of the static var compensators.