Based On The Main Circuit Of The Tsc + Statcom Reactive Power Compensation Device

In recent years, the rapidity increasing of nonlinear, asymmetrically and impact reactive load lead the electric energy quality to worsen, in order to improve the stability of electric power system and the electric energy quality, the necessity to develop the big capacity and fast respond reactive power compensation device is becoming more and more extrude. STATCOM has ascendant dynamic feature, but its configuration is complex, and its cost is valuableness; TSC has the characteristics of simple structure, low investment cost, if could combine the advantages of the two kinds of reactive power compensation devices have very high project values.The thesis introduces the principle of reactive power compensator, the main electro circuit and operational principle of TSC and STATCOM. The transient state process after TSC switched and the methods for increasing capacity and reducing harmonic are analyzed. The defect of instantaneous reactive power theory in three phase imbalance system is expounded, and the reactive power detection method using single phase struck three phases is introduced briefly.Combine the characteristic of the traction power supply system of electrified railroad in my country, the main circuit organization of TSC+STATCOM reactive power compensation device is designed, the structure of TSC, the selection of trigging time, the structure of STATCOM and the theory how to create trigging pulse for the inversion bridge are mainly analyzed and designed, the main parameters of the STATCOM+TSC equipment are precisely researched and designed precisely.The simulation model of reactive power compensation device based on TSC+STATCOM is built in MATLAB/SIMULINK environment, the result for the simulation indicate that the reactive power compensation device of TSC+STATCOM can compensate the dynamic reactive power of the railway traction power supply system effectively, compared with the traditional reactive power compensation device of TSC+TCR, the reactive power compensation device based on TSC+STATCOM can not only compensate the dynamic reactive power of the railway traction power supply system quickly and continuously, but also the harmonic content is very low, because the STATCOM adopt three electrical level four multiplex structure. Although the cost of STATCOM is higher then TCR, but the device to eliminate harmonic is omitted, so the total cost of the device is not increase.