中文摘要：

针对脉冲宽度调制模式下采用比例控制的三电平磁轴承开关功率放大器的非线性现象进行了研究,采用频闪采样法建立了全桥变换器的离散映射模型,并基于此模型分析了全桥变换器的分岔稳定性和混沌特性,展示了全桥变换器混沌现象的动态演化过程。利用数值计算确定了电流控制器比例系数、载波频率和母线电压的稳定调节范围,并计算了李雅普诺夫指数图验证混沌现象存在。仿真及实验结果表明降低电流控制器比例系数和母线电压,提高载波频率有利于消除混沌现象,从而提高三电平全桥变换器的稳定性。

英文摘要：

Three-level switching power amplifier for magnetic bearings using proportional controller in the mode of pulse width modulation is studied.Based on this model,discrete mapping model of the full bridge converter was set up by stroboscopic sampling,and the stability of bifurcation and chaos characteristics were analyzed.The dynamic evolution process of converter chaos phenomena was directly exhibited.The stable adjustment range of proportional control coefficient,carrier frequency and bus voltage were determined by numerical calculations,and the Lyapunov exponents were calculated to verify the existence of the chaotic phenomenon exists.The simulation and experimental results demonstrate that chaotic phenomena can be eliminated by reducing proportional coefficient of current controller and bus voltage,and increasing the carrier frequency,which enhances the stability of the three-level full-bridge converter.