China International Youth Conference on Electrical Engineeing (CIYCEE 2025)

Heavy-haul locomotives place high demands on their traction systems, which must deliver strong, continuous pulling power and also be extremely reliable. Using multiple Permanent Magnet Synchronous Motors is a major step forward, improving power density, efficiency, and system redundancy. However, the main challenge is how to make these motors work together to achieve a consistent total traction torque. This task is made much more difficult by a known weakness in PMSMs. To solve this key reliability problem, this report presents a complete framework called Demagnetization-Tolerant Coordinated Traction Control. This framework includes three main parts: detecting the degree of magnet weakening in real-time, robust speed control for the PMSMs, and a coordination strategy for the total traction torque output. The proposed DTCTC framework can successfully identify demagnetization faults. Under these faulty conditions, it greatly reduces dips or spikes in the total torque and maintains fair load sharing among the motors. This greatly improves the robustness and operational reliability of the heavy-haul locomotive's traction system.