DESIGN OF A BATTERY VOLTAGE REGULATOR BASED ON MAXIMUM POWER POINT TRACKING AND CHARGE EQUALIZATION CONCEPTS

This paper deals with loss of photovoltaic energy due to mismatch betw een PV array and battery-bank, and difference in equalisation of charg e between cells of battery-bank, These are the two major problems that affect the performance and life of PV system, From I-V characteristic s of PV modules and the charging-discharging characteristic of the bat tery-bank it is shown that in contrary to general assumptions and prac tices the maximum power point tracker is still relevant, even for a PV system integrated with battery-bank. From charging and discharging cy cles of the battery-bank, it was observed that there is a need of char ge equalisation among different battery-cells, For overcoming the abov e limitations a battery voltage regulator (BVR) has been designed to u tilise the maximum available PV energy and also to provide charge equa lisation to different battery cells, This BVR is based on multiple out put switch mode design, The control function is based on analog positi ve feedback control for pulse width modulation, The BVR has been fabri cated and tested. The increase in utilisation of available solar power lies between 5% to 10%.