Design and Implementation of a Photovoltaic Power System with Bi-Directional Inverter

[[abstract]]A PV power system with bi-directional inverter is proposed in this paper. The system is divided into two stages, one is power stage, which contains DC/DC converter and bi-directional inverter, the other is control stage. Both stages control schemes are by a micro-controller dsPIC30F4011. For preventing from high current harmonic caused by the two stages, a predictive current control and modulation principle are designed and operated in high frequency to reduce the current harmonic. The bi-directional inverter can operate in grid-connection (GC) mode or power factor correction (PFC) mode. But the core material of inductance will result in violent current ripple change when the inductor current promoted. So, a gain modulation is used to compensate various inductances used to reduce grid-connection current ripple. Finally, the system is implemented to verify the feasibility and performance of the proposed system