Design Of Control System For Magnetic Bearings Based On DSP2812

Active magnetic bearings (AMBs) make rotor suspended by magnetic force. Since AMBs have many advantages of no friction, no abrasion, no lubricated, lasting life, maintenance-free to the traditional bearings, they are attracting more attention gradually. However, in addition to the part of the machine, the control system is very important for AMB system, the nature of it affects the dynamic performance of AMB system and control precision of the rotor. Taking five-freedom-degree AMB as research object, the digital control system of AMB, is studied in this paper. By means of the DSP chip, the control hardware plan is made, and the neural network control algorithm are discussed. The main contents of the paper are listed as follows:The structure and the relation of five-freedom-degree AMB are described in detail. By the principle of the Electromagnetic Theory, the electromagnetic force expressions are deduced from the model of the single-freedom-degree AMB. Further more, the control model of the five-freedom-degree has been established.According to feature and designing desire of AMB, the DSP hardware plan is made, with the peripheral equipments of grouping DA,CPLD, etc. The hardware plan improved the stability and reliability, simplified the system's structure, and reduced the system's price.The study of AMB control algorithm has been developed. After thorough analysis on the the theory on the neural networks, based on the control model of the single-freedom-degree, the BP neural compensation controller which making using of the high mapping ability of neural network has been discussed on this paper. The output of the controller contains the non-linear combination of proportional, integral and differential signal, which reduces the nonlinear effect of the system. The experiment indicates that the control characteristics are much superior to the traditional PID controller.The design of the software which composed of the control software in DSP and the monitor software in computer is finished based on the C&assembly language. The control software include the system initialization model, the high speed AD model,the DA output model,the control algorithm model and the communication modle.According to the requirement of debugging and controlling,the monitor software has been designed which use VB,it realized the debugging and controlling of the AMB system.