Abstract :

Three-phase transformer inverter is commonly used in photovoltaic (PV) grid-connected systems due to its high efficiency and low cost. There is no galvanic connection. In these conditions, common mode leakage Currents can appear through the capacitance between the PV array and the ground. In order to create a galvanic isolation between the input and the output include a transformer that reduces the whole system performances in terms of efficiency, weight, size and cost. On the contrary, transformer less inverters absent of any isolation and are characterized by little size, lower cost and higher efficiency (more than 2% higher). The shortage of transformers leads to leakage currents that can be harmful to the human body, as well as for the whole conversion system integrity. Triggering pulses are given using Pulse Modulation (PWM) technique through Data Acquisition (DAQ). In order to reduce the ground leakage current and improve the efficiency of the converter system, transformer less PV inverters by using of unipolar PWM control is proposed. In this paper, a three-phase grid based inverter that operates the super junction Metal Oxide Semiconductor Field-Effect Transistor (MOSFET) to accomplish high efficiency for photovoltaic applications is introduced. Also three phase transformer less inverter with Permanent Magnet Synchronous Motor (PMSM) under LabVIEW platform is developed.