Control Strategy For Low Loss Active Magnetic Bearing

The setup of vertical axis wind power generator rotor system supported by fivedegrees of freedom active magnetic bearing is built. Analog controller based on the modeof zero bias current, and digital controller based on TMS320F28335DSP, the mode ofvariable bias current and fuzzy control strategy are developed separately. The influenceof the modes of zero bias current and variable bias current on dynamic characteristics ofthe system is investigated respectively by test method. In view of the poor outdoorworking conditions of wind power generator, power amplifier with redundant function isdeveloped to improve the reliability of the system. Moreover, axial active magneticbearing with brake function is also developed to replace the traditional electromagneticbrake component.The results show that, analog controller based on the mode of zero bias current cankeep the amplitude of vibration of the rotor within bounds and the system can operatesafely. However, compared with the mode of variable bias current, the amplitude ofvibration is larger and the stability region of control parameters is smaller. Fuzzy variablebias current control strategy can insure smaller amplitude of vibration of the rotor andlower power loss of magnetic bearing.The system has higher comprehensive properties.In addition, the power amplifier with redundant function and the axial active magneticbearing with brake function can work effectively.