Controller of high-speed electro-spindle with AC HMBs based on optimal control theory

A state equation for an electro-spindle supported by five degrees of freedom AC hybrid magnetic bearings is built, and the approach on how to use linear quadratic method of optimal control theory to design centralized and decentralized parameter controllers is introduced. The simulation analysis between the centralized and decentralized parameter controllers is conducted with MATLAB software. The digital control system based on TMS320F2812 DSP for AC magnetic bearings has been designed and tested using the decentralized control arithmetic. The research results have shown that the decentralized controllers based on linear quadratic method meet performance requirements of the AC magnetic bearing system, and has good control effect when the speed of the rotor operates under 30 000 rpm.