Voltage Oriented Based Control Strategy for Cascaded PWM STATCOM

This paper presents a three-phase 2N+1 level transformer less cascaded pulse width modulation (PWM) static synchronous compensator (STATCOM) that intended for installation on industrial and utility power distribution systems. Based on voltage oriented control (VOC), this paper proposes a control algorithm that devotes itself not only to meet the reactive power compensation but also to voltage balance of isolated and floating dc capacitors of each H-bridge converter. Based on the relationship of reactive power and active power for each H-bridge converter, the proposed control system is detailed, and the simulation results also demonstrate the validation of proposed control strategy.