Abstract: Based on actual wind field operational data, this study analyzes the impact of high-frequency harmonics and DC bus voltage fluctuations on capacitor lifespan, proposing a systematic solution that includes thermal management co-optimization, parameter multi-objective optimization based on lifespan models, and parallel configuration optimization. Stress decoupling is achieved through model predictive control, while the NSGA-II algorithm is employed to optimize capacitor reliability, cost, and volume. A scaled-down experimental platform was established for verification, demonstrating a 12.34 ℃ temperature reduction, a voltage ripple rate decrease to 1.27%, and a lifespan improvement to 2.18 times the original. This provides a theoretical foundation for the reliability design of wind power converter filter capacitors.