PWM based Double loop PI Control of a Bidirectional DC-DC Converter in a Standalone PV/Battery DC Power System

In this paper, a pulse width modulation based two loop PI control technique is proposed to control the load bus voltage magnitude in the presence of constant power load in standalone PV/Battery dc power system. Inner loop controller is used to control the inductor current and outer loop controller is used to control the load bus voltage. Both controllers are tuned and their stability is observed by frequency domain measures. Instantaneous maximum power is drawn from photovoltaic array by Incremental Conductance algorithm using a DC-DC boost converter. The effectiveness of the proposed method is validated using MATLAB/Simulink software for different solar irradiation and varying load conditions.