DC Bus Voltage Stabilization Control Considering Power Loss of the Full-Quadrant Operated Inverter

This paper proposed a DC bus voltage stabilization control strategy of the full-quadrant operated three-phase grid-connected inverter, of which the reactive current is not 0. The strategy considers the power loss of the switches caused by both active and reactive current, which would affect the dynamic performance of voltage loop. In this condition, the power loss can be seen as a disturbance of the voltage loop so it should be taken into consideration in the design process. Besides, the voltage loop is the outer loop of the active current loop. The active and reactive current are coupled because of the coordinate transformation. As a result, the interference of the reactive current would affect the DC bus voltage through current coupling. The proposed control strategy considers the power loss and designs the outer voltage loop. Also the decoupling current controller based on complex vectors is discussed. With the proposed DC bus voltage stabilization strategy, the inverter can realize good dynamic and static performances. The control principle is analyzed in detail. The design of the control loops are discussed. The influences of the reactive current on the DC voltage and active current are analyzed. Finally, the simulation and experimental results verify the theoretical analysis.