Simulation and stability analysis of a 100 kW grid connected LCL photovoltaic inverter for industry

In this paper a 100 kW grid connected photovoltaic (PV) system is simulated. A full 3 phase current controlled PWM bridge inverter with a passive LCL filter is used for interfacing with the utility and named as power conditioning unit (CU). The main functions of CU are maximum power point tracking control (MPPT) and power factor correction for compliance with both standards IEEE 929-2000 and IEEE 519-1992. Two loops control the CU, an outer loop for MPPT and an inner loop for power factor correction using a P + resonant controller. The MPPT algorithm, the LCL filter and controllers designs are discussed and simulation results show the validity of that PV system under various weather conditions