Voltage Drop Compensation Technology for High-Voltage and High-Power DC Energy Storage Power Supply System
Zihe Meng, Jiandong Duan, Li Sun
Abstract
This article presents output voltage drop compensation technology for high-voltage and high-power dc energy storage systems (DC-ESS). This technology is used to improve the output voltage stability of high-voltage high-power DC-ESS in high rate discharge. The proposed output voltage drop compensation technology includes an ESS architecture and a corresponding control method. The proposed ESS architecture adopts a dc dynamic voltage regulator (DC-DVR) to compensate for output voltage drop. DC-DVR adopts a six-phase interleaved parallel buck converter. This architecture not only maintains the system output voltage stability but also reduces the system cost. Moreover, the proposed ESS architecture does not change the original energy storage capacity. The dynamic power flow of the proposed ESS architecture is analyzed and a direct power control method based on full response power compensation is proposed. The steady-state power and dynamic power of the proposed ESS architecture are compensated so that the input power can quickly track the change of the output power. The proposed control method improves the stability and dynamic response speed in the system's dynamic process. Simulation and experiment verify the effectiveness of the proposed ESS architecture and control method.