As a critical component of railway systems, existing trackside equipment relies on centralized indoor power supply screens for power. However, this configuration suffers from inherent drawbacks such as excessive cable lengths, high deployment costs, and significant voltage fluctuations. To address these issues and adapt to the distributed control scenarios of urban rail transit, this paper proposes a safety-oriented, digitally controllable AC/DC conversion circuit design tailored for trackside installation and miniaturization. Adhering to the fault-safety principle and two-out-of-two redundancy architecture, the circuit converts mains AC220V to adjustable DC output ranging from 24V to 200V. The module integrates a dual-processor control unit, power conversion circuit, voltage/current acquisition circuit, and weak current voltage conversion circuit. Key design features include electrical isolation via a high-frequency transformer, enhanced power conversion efficiency through phase-shifted full-bridge control, real-time monitoring of input/output voltage, output current, and board temperature, and bidirectional real-time communication with external devices. Notably, the circuit is designed to fail safely: in the event of abnormal acquisition signals or hardware malfunctions, the system automatically switches to a safe state with no power conversion output. To validate the design feasibility, a 1kW experimental prototype was fabricated and tested, with results confirming the effectiveness of the proposed solution.
Xing et al. (2026) studied this question.