Adaptive Digital Control Addressing Inductance and Bus Voltage Variation in PFC for Energy Storage Systems (ESS)

This paper presents digital adaptive current control of PFC to address variable boost inductance and variable bus voltage. The proposed approach is particularly suitable for Energy Storage Systems (ESS) and PFC applications in general. Digital control is implemented through a simple proportional integrator (PI) regulator, and Bode stability analysis is conducted for different inductances and bus voltages. Then, a low processing and low memory MCU implementation is presented. The effectiveness of the proposed adaptive control is validated in a SiC-based 7-kW PFC platform for ESS, showing significant steady-state performance improvements (THDi, PF, and efficiency) over traditional methods with fixed control parameters. Finally, transient tests demonstrate the robustness of the proposed control also in dynamic conditions.