Dynamic characteristic analysis of multi-bridge PWM inverter for SSSC

This paper proposes a static synchronous series compensator (SSSC) based on multi-bridge inverters in a PWM scheme. The dynamic characteristics of the proposed SSSC was analyzed by simulation with EMTP codes, assuming that the SSSC is inserted in the transmission line of a one-machine-infinite-bus power system. The proposed SSSC has 6 H-bridge inverter modules per phase, which generates 13 pulses for each half period of power frequency. The proposed SSSC generates a quasi-sinusoidal output voltage by 90° phase shift to the line current. The proposed SSSC can be directly inserted in the transmission line without coupling transformers, and has flexibility in expanding the operation voltage by increasing the number of bridges in series connection