고전력 서보모터 구동을 위한 슈퍼커패시터 기반 DC-link 충전시스템의 개발

초록

This study presents the design and experimental evaluation of a supercapacitor-based direct current (DC)-link charging system for high-power servo motor applications. High-power servo systems require substantial instantaneous power during startup and rapid acceleration that can cause voltage drops and system instability under limited power supply conditions. To address this issue, a supercapacitor-based DC link energy-buffering architecture is proposed. In the proposed system, the main power source is electrically decoupled from the DC link energy buffer. The supercapacitor module is charged during low-load operating conditions and subsequently supplies the stored energy to the DC link during high-load operation. The charging strategy integrates voltage-threshold-based hysteresis control with constant-current charging to maintain the DC link voltage within a predefined operating range. A supercapacitor module with a total capacitance of 6.25 F and an operating voltage range of 440–480 V was developed and experimentally validated. The experimental results demonstrate stable charging performance of the proposed system. The supercapacitor module was successfully charged from approximately 10 V to 480 V under stable constant-current operation conditions. The measured charging time was approximately 80 s, and the measured voltage profile exhibited good agreement with the theoretical prediction for constant-current charging. These results verify the effectiveness of the proposed charging strategy and demonstrate the feasibility of employing a supercapacitor-based DC link charging system in high-power servo motor applications operating under limited power supply conditions.

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