具有死区补偿的磁轴承开关功放数字单周期控制

Digital One-Cycle Control Algorithm with Compensation of Dead-Time for Switch Power Amplifier in Magnetic Suspension Bearings

在磁轴承全桥功率开关功率放大器系统中,单周期控制算法具有实现简单、响应速度快等优点,基于全桥功率放大主电路拓扑时,传统的单周期控制算法没有考虑全桥功放固有的死区效应对系统动态性能的影响。该文分析了单周期控制算法的原理,在此基础上考虑磁轴承线圈电阻压降以及死区效应的影响,提出了一种具有死区补偿的单周期控制策略。对补偿前、后的数字单周期控制算法进行仿真对比分析,仿真结果表明补偿后的单周期控制算法反馈电流能够准确的跟踪给定电流,且谐波含量减小,验证了控制策略的优越性。

Adopted in switching power amplifier for magnetic suspension bearings,digital one-cycle control has advantages of simple structure,easy realization,and rapid response.However,digital one-cycle control does not consider the inherent dead-time effect of the full-bridge power amplifier,which will influence the system stability.The principle of one-cycle control was analyzed with the consideration of resistance voltage drop and effect of dead-time,proposed one-cycle control with dead-time compensation.The simulation results show that the current can follow the reference with the compensated one-cycle control algorithm,and the harmonic content is reduced,which verifies the superiority of the control strategy.