P-controller based photovoltaic battery diesel (PVBD) hybrid system management and control

This paper presents a control strategy of photovoltaic-battery-diesel (PVBD) hybrid power system. The PVBD system configuration is introduced and the required control signals are estimated. The sampling rates of each control signal-PV array current signal, load current signal and battery state of charge (SOC) signal-are determined based on the operation behavior of power system components. The driving circuits of the PV array, the battery charger as well as diesel generator status (ON/OFF) and control (start/stop) are designed and implemented. The system modes of operation at different operating conditions during the daylight and night periods are defined and their operating conditions are determined. The control strategy flow chart is introduced and the controller management program is developed in assembly language format, wherever the controller is 8051 microcontroller based. The controller program is designed (proposed) based on the P-controls technique, where the Kp parameter is being auto-tuned factor to be relevant for weather parameters (mainly insolation) changes.