Design and implementation of a five-phase six-leg switching power amplifier for five degrees of freedom magnetic levitation bearing system

A five-phase six-leg switching power amplifier was designed for five degrees of freedom (5-DOF) magnetic levitation bearing system. This amplifier carries characteristics of small size and simple control. This study analyzes its structural composition and operating principles. The control of 5-DOF magnetic levitation bearing was achieved through combination of hardware and software control, i.e. the common bridge legs utilized the maximum current error control method; whereas the load bridge legs adopted the sample-hold modulator. In order to verify its rationality and correctness, the simulation software MATLAB was used. The output current waveform at speed of 6000 r/min was plotted. The experimental results show that the amplifier has excellent overall performance to meet the requirements of actual applications.