Non-ideal two-level battery charger—modeling and simulation

Abstract

A comprehensive analysis of a two-level battery charger model is presented, focusing on its switched and averaged dynamics validated via MATLAB Simulink simulations. The system, powered by an 800 V DC source, is managed by a robust PI-compensated feedback loop, delivering minimal ripple, rapid transient response, and high stability under varying load conditions. Results demonstrate precise battery current control with a 4 ms settling time for step changes and ripple levels kept below 0.16% for current and 2.4% for capacitor voltage. Sensitivity analyses highlight the impact of non-ideal resistances—such as MOSFET on-resistance and inductor resistance—on efficiency and equilibrium voltage stability. Stability and loop gain studies confirm robust control performance, with all poles positioned in the stable region of the s-plane, ensuring reliable operation. This work provides key insights for designing high-efficiency, stable battery chargers and supports the use of advanced control techniques to further enhance converter performance.

Keywords

• battery chargers
• electric vehicles
• power electronics
• proportional-integral control
• switching converters
• sensitivity analysis