Research on the Impact Mechanism of High Peak-to-Average Pulse Loads and Their Mitigation Strategies

The periodic transient characteristics of high peak-to-average pulse loads (HPAPLs) can cause continuous strong impact effects on the medium-voltage DC integrated power system (MVDC-IPS) of ships, leading to oscillation instability or even disconnection and shutdown of diesel generator sets. To tackle this challenge, this paper initially establishes a comprehensive dynamic mathematical model of HPAPL, and studies the impact of HPAPLs on system stability under different operating conditions. It identifies that the cause of this impact is the shock current of HPAPLs. Furthermore, a hybrid energy storage system (HESS) is proposed to compensate for this shock current. By coupling the simplified mathematical model of the HESS with the mathematical model of HPAPLs, the system’s Jacobian matrix is obtained. The feasibility of this strategy is verified based on the analysis of eigenvalue trajectories. Finally, considering the effects of various disturbance factors on the compensation accuracy of the HESS, a control strategy for the HESS based on parameter adaptive virtual DC motor (VDM) control is proposed to improve the adaptability of HESS. Lastly, based on the RT Box 3 hardware-in-the-loop simulation platform and experimental, a MVDC-IPS with HPAPLs is constructed, and the effectiveness of the proposed control strategy is validated.