Space vector pattern generators for multi-module low switching frequency high power VAr compensators

Force-commutated series-connected multi-converter modules have found applications in SVC and DC transmission stations, high power drive systems, and reactive power compensation units. This paper shows how relatively slow gate turn off (GTO) thyristors may be utilized in multi-converter modules in conjunction with a delayed sampling principle applicable to the space vector modulation (SVM) technique. The paper demonstrates the advantages of the SVM over the other existing modulation techniques in terms of switching frequency, voltage utilization, harmonic distortion, implementation, and control