Disturbance Model for the Integrated PSFB and Inverter System in Grid-Tied PV Applications

A phase shift full bridge (PSFB) converter, working as an MPPT tracker, integrated to an inverter working in grid connected mode for photo voltaic(PV) applications is considered in this paper. This paper proposes disturbance models describing the response of the system to irradiation variations. These models are useful in designing the control loop of inverter DC bus voltage in grid connected mode(current injection). Irradiation to solar panel voltage transfer function derived finds use in designing the input PV voltage control of PSFB converter for maximum power point tracking(MPPT) during grid tied mode. The proposed models are validated by comparing the magnitude and phase of derived models with the fast fourier transform(FFT) result of the switching circuit model. The validation is done in the simulink environment.