Design Of Fuzzy Control System For Brushless DC Motor Based On DSP F2812

Brushless DC Motor(BLDCM) has many advantages such as little volume,light weight,high efficiency,good speed regulation,no commutation spark,no excitation loss and so on,which is widely applied in domestic appliances,transport,medical instrument,numerical control machine,robots and other fields.With the rapid development of modern industry,the performance requriment to BLDCM control system is also more and more higher.It is foreseeable that with price of permanent magnet material and power electronic devices further reduced,as well as gradual improvement of theoretical study for BLDCM driving,BLDCM will have more extensive application prospects.Through reading many documents,development,research,applications and operating principle of BLDCM are introduced in this paper.Fuzzy strategy that based on the ideas of intelligent control is adopted.The characteristics of this method is not dependent on the object model,in order to get the proper control variable by use of fuzzy reasoning control rules.Matlab/Simulink has been uesd to set model and simulink for control system,adopting the fuzzy PI for speed loop and traditional PI for current loop,which provides the basis of theoretical analysis for experiment.According to structure of BLDCM,hall element inside motor is used to detect rotor position;the fuzzy control table is given on the basis of fuzzy controller.Digital signal processor F2812 of TI company is used as main control chip.Design for hardware of system are as follows:rectifier,inverter,driving,adjusting and protection circuit;control program for system is realized by c and assemble mixd language under the CCS developing environment,which realizes function that contains reading signals,producing PWM wave,sampling of AD,fuzzy PI adjusting for speed and traditonal PI adjusting for current etc.After completing joint debugging of hardware and software for system, experiment is implemented.Compared to conventional control system,the fuzzy PI control system has advantages of quicker response,smaller overshoot,stabler performance.Results of experiment show that design for fuzzy control system of BLDCM is correct.Summaries for the whole design are given and options for subsequent work are put forward finally.