Simulation of Single-Phase on-Grid Photovoltaic Inverter for Power Injection and Active Power Filter

Abstract

Currently, most photovoltaic (PV) sources are connected to the grid. This research discusses single-phase on-grid PV inverters. A two-stage inverter which consisted of a boost-type DC-DC converter and a single-phase inverter, was used. In addition, the inverter improved the power quality to deliver PV maximum power. The entire power generated by PV was to be delivered to PCC, and power quality in PCC was also improved. In this system, the grid only drew or supplied active power. The P&O algorithm, as a simple algorithm, was used to control the boost converter to obtain the maximum PV power. In a single-phase inverter, the DC link voltage regulation was carried out using the PI control (outer loop), while the hysteresis control was used to control the output current (inner loop). The voltage control regulated the power delivered from the PV to the PCC by maintaining a constant DC bus voltage at the specified value. With the current control, a single-phase inverter provided two compensations: reactive power and harmonics. In this research, a simulation to control a two-stage inverter was created by using PSIM. Irradiation for PV was varied between 0-1000 W/m2 for 5 seconds. The simulation results showed that the controls performed could work well, as shown by the maximum power injection from the PV to the PCC in which the grid current was sinusoidal (harmonic mitigation) and reactive power compensation was performed.