Asymmetric SPWM used in inverter grid connected

The overall efficiency of grid-connected photovoltaic power generation systems depends on the efficiency of the DC-into-AC conversion. Therefore, a key consideration in the design and operation of inverters is how to achieve high efficiency with power output. This paper presents a concept of an inverter for grid connected photovoltaic arrays which can synchronise a sinusoidal current output with a voltage grid. Asymmetric PWM inverters can generate power at unity power factor, this approach, based on the active filter is proposed in this work. This method is used in order to correct the phase between the output current and the grid voltage and to maximize the system efficiency in design and control. The functional structure of this system is presented and simulated. Detailed analysis, Simulations results of output voltage and current waveform demonstrate the contribution of this approach to determinate the suitable control of the system. A digital design of a generator SPWM using VHDL is proposed and implemented on an Xilinx FPGA.