Keywords: grid connected inverters, maximum power point tracker, FPGA, photovoltaic systems, power factor control, Malaysia, simulation, topology inverters, symmetrical PMW, pulse width modulation, PWM switching, harmonic current distortion, galvanic isolation, power electronics, solar energy, solar power
Performance of grid connected inverter with maximum power point tracker and power factor control
Detailed analysis, simulation and hardware results of grid connected inverter with maximum power point tracker and power factor control in Malaysian climate are presented. A six-switch topology inverter with symmetrical pulse width modulation (PWM) switching technique is used. A low-pass filter is incorporated in the circuit to filter out unwanted harmonics and produce a sinusoidal AC current. Low total harmonic current distortion at the inverter output can be achieved. The three-phase PWM switching pattern was developed using Xilinx FPGA. The developed system is also capable of adjusting the power factor to unity. A 3 kVA power transformer with a 1:2 ratio is constructed to provide galvanic isolation for better circuit performance and circuit protection. Hardware results for proposed solar photovoltaic inverter configuration interconnected to the grid are also presented. From the experimental results, it is confirmed that the harmonic distortion of the inverter output waveform is within the limits laid down by the utility companies.