Sliding mode control of a bidirectional grid connected three phase two-stage PV system with space vector PWM

A bidirectional grid connected three phase two-stage PV system with DC loads is studied in this paper. The dq frame model is derived in detail, which simplifies the analysis and the controller design. With the dq frame state space model, the switching signals are also converted to the dq frame, which decouples the control input under the dq frame. An adaptive law is designed to estimate the unknown reference value of direct-axis current. The three phase converter can work bidirectionally according to the signal of the direct-axis current. Then the power balance between the PV generation and grid can be realized dynamically. Simulation results show the effectiveness of the proposed control scheme.