A novel, high-frequency, per-phase static VAr compensator

Static VAr compensators are being used to provide voltage control, VAr compensation, damping of oscillations, and improved transient stability in power systems. Conventional SVCs which consist of thyristor-switched capacitors and thyristor controlled inductors suffer from disadvantages of size and slow dynamic response. This makes it unsuitable for applications such as controlling the voltage flicker due to arc furnace loads. Advanced SVCs (STATCON or STATCOM) eliminate the above disadvantages. However they have a disadvantage due to the presence of a large line-frequency transformer. In this paper, a novel, high-frequency, per-phase static VAr compensator is proposed which has all the advantages of the advanced SVC. Various related topologies and control strategies are also enumerated and their advantages and disadvantages are discussed.