Abstract: To address the challenge posed by variable speed loads participating in frequency regulation, we propose a model predictive control strategy that integrates coordinated capacitor energy management and motor speed regulation. This strategy aims to achieve active responses of DC voltage and speed, thereby optimizing system dynamic frequency. A frequency-voltage-speed state space model is established to reveal the mechanism of regulating motor and capacitor energy storage. A frequency prediction model considering operation constraints is established, and a cost function is proposed considering frequency dynamic response and optimal regulation performance of motor-capacitor. Additionally, an optimized weighting factor tuning method based on frequency regulation demand is proposed, which achieves coordinated control of motors and capacitors. Finally, a ship integrated power system is established on the RT-LAB experimental platform. Experiments show that the scheme achieves adaptive coordinated control while enabling the variable speed loads to fully participate in frequency dynamic regulation.