Adaptive Pi Controller Based Control of Spu for Maintaining Constant Cpi Voltages

Abstract

Solar photo Voltaic (SPV) systems based grid interfacing systems involve two stage power conversions. This conversion requires Maximum Power Point Tracking (MPPT) based boost converter that can supply a constant DC link voltage with a SPV as its input as the first stage. The second stage conversion involves a two-level Voltage Source Converter (VSC) that serves as an inverter which feed power from the boost converter to the grid. To meet the grid requirements the voltage at the Common Point of Interconnection (CPI), the voltage of the inverter must be made equal to the voltage of CPI. This can be done adjusting DC link voltage of stage one of the converter. This can be achieved by using anadaptive feed forward Proportional and integral Controller (PI). The advantage of this controller is that it improves dynamic response, reduces the switching losses and provides robust response under grid voltage variations. The performance of the system is verified with the help of MATLAB based simulation studies and the case studies are presented