Study On Control System Of Rotor Radial Displacement In Magnetic Bearing

Magnetic bearing is a kind of novel high-performance bearing , in which rotor can be suspended by magnetic force . Because of the contact-free property between the rotor and stator , the rotor can rotate at very high speed , and magnetic bearing has the advantages of long lifetime , low power loss , low noise , almost no wear and no lubrication . Thus magnetic bearing has great advantages over conventional bearing in many application fields.Magnetic bearing is a typical electromechanical integration system , which includes electronic system and mechanical system . The performance of the magnetic bearing is determined mainly by the electric control system . This issue introduce the working principium and the basic parts of the magnetic bearing in detail , and based on investigation of the electromagnetic force , set up the math models of magnetic bearing , establish the theory foundation to design the control system of magnetic bearing . Based on this theory, this issue design the hardware of magnetic bearing control system . The control system's hardware include position sensor, voltage conversion circuit , controller , power amplifier and isolation-driving circuit . Then a digital control system based TMS320F2407 DSP is designed . Through software design on the DSP , the system can realize the A/D conversion , produce PWM pulse , and implement the control algorithm . In the digital control system , the anti-integration PID control algorithm is used. As the accurate mathematic model of magnetic bearing is hard to establish, the PID neural network control is designed for the magnetic bearing system. The PID neural network controller has the ability to study and modify the weight value automatically . Finally , the experimental magnetic bearing is designed and developed . Based on this magnetic bearing , the experiment of stable suspension and impact force are conducted to testify the math model of the magnetic bearing , and provide reliable practical parameter for the experiment followed of the control system.