Improving the Dynamic Characteristics of PMD Battery Charger Using Fuzzy Logic Control

This paper proposes improving the dynamic characteristics of a personal mobility device (PMD) battery charger using fuzzy logic control (FLC). Recently, as the use of PMD has expanded, research on the PMD battery charger has also been actively conducted. To control the output voltage of the PMD battery charger, a simple proportional–integral (PI) controller is mainly used. However, increasing the gains of the PI controller to improve the dynamic characteristics of the PMD battery charger can cause overshoot, oscillations, and sensitivity to disturbances. To overcome these limitations, this paper proposes an FLC-based output voltage control of the PMD battery charger. The proposed control method determined the reference inductor current using the membership functions and output intensity. In addition, the proposed control method exhibits improved dynamic characteristics compared to PI-based output voltage control in the transient state, reducing the settling time by approximately 55.26% and reaching a steady state stably without overshoot. The validity of the proposed FLC-based output voltage control method was verified through simulation and experimental results.