3-DOF H∞ Voltage Robustness Control for PMSG Extended Range Powertrain

Extended range powertrain composed of permanent magnet synchronous generators (PMSGs) are widely used in electric vehicles and more-electric aircraft. Due to the complexity of operating conditions, voltage regulation control plays a critical role in these systems. To address the issues of lack of robustness and dynamic response in traditional voltage regulation control strategies, this article proposes a three-degree-of-freedom (3-DOF) robust voltage control strategy for extended range powertrain based on H-infinity (H∞) control. First, a generalized controlled plant model, including the PMSG, rectifier, and load disturbances, is established. Based on this model, an H∞ voltage control method with an H∞ load disturbance observer (DOB) is proposed to estimate load disturbances. A parameter tuning method for the weighting function is proposed by analyzing the amplitude-frequency characteristics. Furthermore, a 3-DOF H∞ robust control method is proposed, which integrates voltage command feedforward, load compensation feedback, and prime mover disturbance feedforward. This method enhances the dynamic performance and disturbance rejection capability of PMSG extended range powertrain. The effectiveness of the proposed method is verified through the 60-kW PMSG experimental platform. The experimental results validate the superiority of the proposed H∞ control strategy in maintaining voltage stability and improving system robustness against various disturbances.