An experimental system of power grid including photovoltaic system based on TMS320F28027

The proposed experimental system uses TMS320F28027 as the control core to realize the functions of maximum power point tracking (MPPT), synchronizing of the output voltage with the given frequency and phase, under voltage and over current protection, under voltage recovery and others. The topology of the main circuit is a full bridge inverter controlled by the unipolar sinusoidal pulse-width-modulation (SPWM) strategy. The MPPT is implemented using the constant input voltage method. Phase tracking is achieved using a software phase lock loop (PLL). The tested results show that the system has perfect performances, such as high efficiency, low grid-connected total harmonic distortion (THD), excellent tracking performance, consummate over-current (OVC) and under-voltage protections (UVP).