A Novel Preliminary Design Method of PMSM Drive System for Minimizing Acceleration Time of High-Speed and Large-Inertia Flywheel Rotor Load

In the research field of pulsed power system (PPS), high-power and high-energy pulse alternator is used for providing intense pulses of electrical power, whose rotor is designed large to store enough energy for satisfying multi-shot requirement, which can be regarded as a high-speed and large-inertia flywheel. How to design a suitable mechanical drive system with a compact volume for minimizing the acceleration time (AT) from rest to target speed is one of the most concerned issues. The design of motor drive system is an iterative process, especially when co-designing of the motor and its converter. An accurate initial parameter estimate can greatly reduce the costs. Therefore, in this paper, a novel preliminary design method of permanent magnet synchronous motor (PMSM) drive system is proposed. Firstly, a special base value system (BVS) of PMSM drive system is introduced in this paper, and the equations of maximum torque control (MTC) are normalized. Secondly, the design method based on minimum acceleration time curve (MATC) is proposed, and a MATC of turn number design is derived. Thirdly, considering the influence of windage and eddy current losses on the output torque of motor, the corresponding MATCs in low and high vacuum environment are studied respectively. Finally, it is concluded that the optimal turn number coefficient should be greater than 3.5 in the design.