Study On 50Kvar Client STATCOM Using Direct Current Control

With the use of power electronic devices and various non-linar equipments, as well as the constant improvement of the users'higher requirements to power quality, the reactive power compensation issue in the quality of power has become increasingly important. Use static synchronous compensator (STATCOM-Static Synchronous Compensator) to achieve dynamic reactive power compensation is one of active research areas in the power electronic disciplines. However, the current study on static synchronous compensator is mainly concentrated in the transmission system, and the current control methods based on the indirect control. With the impact of switching frequency and switching capacity of the switching devices, the STATCOM devices using indirect current control methods exists harmonic output, and the response speed and the control precision have yet to be enhanced. The STATCOM technology appling in the low-voltage distribution system or industrial load compensation in the country is relatively low at present, and the technology was not mature. This paper introduces a STATCOM device based on the direct current control using in low-voltage distribution system or industrial load according to there characteristics.This paper establishs the mathematical model of STATCOM using direct current control,in this paper we use the operational method of i_p,i_q which based on theinstantaneous power theory to test the operations of reactive current and the harmonic Current;Compared to the direct current control methods,the direct current control are more advantage in the tracking speed and the precision of control,so we design the control section according to the direct current control,and verify by using the MATLAB simulation software;Design the 50Kar STATCOM experimental system used in the three-phase three-wire symmetrical circuits using an advanced TMS320F2812 DSP core chip for hardware and take SPWM technology (SPWM); experiment using the dynamic harmonic vargererator(DHVG) as a simulated load.the results proved the feasibility of the design, but also the good performance of dynamic compensation of the STATCOM.Comparing with the results of the simulation and experiment to proved the feasibility of the design; through the fundamental reactive power compensation experiments and dynamic response experiment of the STATCOM to prove the good performance of reactive power compensation and dynamic response speed.