Fuzzy Sliding Mode Controller for Series Connected Solar Boost Inverter

Abstract

The paper develops a Fuzzy Sliding Mode Controller (FSMC) for improving the quality of power delivered to the load through two boost inverters connected in series from a Solar PV system. It includes a front end KY converter, which together with the capacitor offers a constant dc link voltage to the inverter. The framework evolves a rule based principle for engaging the gain of the FSMC to derive the reference, in an effort to modulate the pulse width modulation (PWM) pulses for the switches in both the inverters. The performance evaluated using MATLAB based simulation brings out the relative merits of the controller in terms of a lower total harmonic distortion (THD) and higher harmonic spread factor (HSF) for the output voltage of the inverter. It further exhibits the ability to ensure equal sharing of voltage among the inverters connected in series at the output and assuage to regulate the load voltage over the operating range. The experimental readings obtained from a prototype validate the simulation results and allows the claim for the use of the control strategy in similar practical systems.