Self-adaptive phase compensation characteristics and safeguard-phase-margin design of an unsymmetrical current-sensing resistor for magnetically suspended flywheels:

This paper presents the self-adaptive phase compensation characteristics and quantitative design of an unsymmetrical current-sensing resistor for magnetically suspended flywheel (MSFW) system with strong gyroscopic effects. Aimed at the nutation stability of the MSFW control system, the self-adaptive phase compensation characteristics of PWM H-bridge unipolar switching power amplifiers with unsymmetrical current-sensing resistor with inductance variations is analyzed firstly, including the initial compensation frequency and compensation phase in the compensation working regions. Secondly, the quantitative safeguard-phase margin design method for the asymmetrical factor in H-bridge unipolar switching power amplifiers is proposed based on the nutation stability criterion. Finally, the influence of the unsymmetrical current-sensing resistance network on the nutation stability is further analyzed. Simulation and experimental results demonstrate the correctness and effectiveness of the proposed method.