Maximum power point tracking (MPPT) battery charger for a small wind power system

Abstract

This paper focuses on charging process of the battery charger for a small wind turbine system to track the highest power point in order to harvest the maximum output in the wide range of wind speed variations. The Maximum Power Point Tracking (MPPT) method with the assistance of classical Proportional-Integral-Derivative (PID) controller is used. The issue regarding how this charging process is managed was studied. Smart management during battery charging process is significantly required since the lack of charging management may affecting the battery’s performance, particularly in terms of its lifetime and the degradation rate. Hence, in this paper, a battery charger with an effective performance is designed using the concept of controlling the pulsating charging current which is implemented by discontinuous conduction mode operation of a power converter. Results show that the efficiency of the charging process is good since the resulting pulsating current is working as expected and protection scheme worked well during the charging process by using buck-converter. This method enables the overcharging and overvoltage to be avoided. Besides that, it provides another feature where the self-discharging process can be avoided by providing small current flow in order to prolong the battery’s lifetime.