磁悬浮轴承开关功率放大器及其电流控制策略优化研究

Switching Power Amplifier and Its Improved Current Control Strategy of Active Magnetic Bearing

为优化磁悬浮轴承系统的响应速度及系统稳定性,文章通过分析磁悬浮轴承开关功率放大器性能特点,提出了一种五轴共桥臂拓扑结构,其具有器件少、损耗小等应用优势;同时在分析磁浮轴承控制系统传递函数的基础上,推导出了使系统稳定的电流环带宽、系统阻尼与系统刚度的限制条件,并设计了一种基于模型预测的电流控制策略,其能显著提高电流环的响应速度,进而改善系统的总体性能。经仿真与实验证实,采用五轴共桥臂拓扑结构能够降低50%的系统损耗,且基于模型预测的电流策略能显著提升系统响应速度并保证系统的稳定性。

In order to optimize the performance of the magnetic bearing system,a five-axis common-bridge arm topology structure is proposed by analyzing the performance characteristics of magnetic bearing switching power amplifier,which has the advantages of less devices and less loss.At the same time,on the basis of analyzing the magnetic bearing control system transfer function,the system current loop bandwidth and the damping and stiffness of the constraints are deduced,and a current control strategy based on model prediction is designed,which can significantly improve response speed of current loop and overall performance of system.Simulation and test results show that the five-axis common bridge arm topology can reduce the system loss by 50%,and the current strategy based on model prediction can improve the system response speed and system stability.