Development of a voltage source inverter based static VAr generator

A 300 kVAr advanced static VAr generator (ASVG) utilizing gate turn-off thyristors (GTO) was developed successfully by Tsinghua University, China. In this paper, by using a phasor diagram to reveal the relationship between Us (voltage of system), Uc (voltage of DC capacitor), /spl delta/ (phase angle difference between voltage of ASVG and system) and /spl theta/ (pulse width of squarewave of inverters), a detailed description of its operating principles is given. This 300 kVAr ASVG is composed of 18-pulse multiple inverters and typical tests show that the experimental results of an ASVG with this kind of structure (such as harmonic level, steady-state and dynamic performance) are as expected.