Development And Application Of 10kV Dynamic Static Var Compensator

With the fast development of power industry, the capacity of power system is increasing, and the structure of electric grids is more complex and enormous, so the stability problem of power system is more notable. At the same time, the impactive loads and nonlinear loads are increasing largely, and the fluctuation and flicker of voltage and the low power factor are more severe. Therefore, it is necessitated the search and application of new power controllers to minimize losses and maximize the stable power-transmission capacity of exiting lines, and solve power quality problems. Presently, Flexible AC Transmission System (FACTS) technology, based on the application of a variety of new power-electronic controller for active and reactive power on selected lines, is becoming an integral component of modern power transmission and distribution systems. The objective of this dissertation is to analyze the interactions among the shunt FACTS devices, SVC etc, for voltage control on a transmission and distribution lines. The static and transient stabilities can be improved, voltage flicker can be restrained, and power factor can be increased, so these FACTS devices are attached more importance.As a main solution to compensate reactive power, static var compensator based on thyristor-controlled can compensate reactive power preferably. In this article, the theory and control means of SVC based on thyristor-controlled have been researched, and the mechanism of SVC to control voltage and improve stability of system has also been analyzed. Aimed at compensating object, the suitable structure, parameters and control strategy have been selected through analyzing and comparing. Then a 0.4kV, 150MVar capacity-adjustable SVC equipment based on DSP-controlled has been developed. The results of actual test and field work show that control strategy is valid and creditable, and the equipment can compensate reactive power efficiently and its respond speed is high. Voltage of load has been stabilized and power factor has been increased.