The Controller Design For BLDCM Of Sea Robot

The topic of this thesis comes from a science and technology item of Liaoning Province: The Research of Brushless Thruster for Deep-sea Robot. Permanent Magnetic Brushless DC Motor is selected as drive motor of the Deep-sea Robot. The drive system is required to work in forward and backward mode and realize high precision speed regulating.in this thesis, the Brushless DC Motor controller of Sea-Robot based on DSP technology is researched.Firstly, the composing parts, math model and the principle of regulating speed of BLDCM are discussed. Secondly, the control algorithm of motor is reseached. Dual closed loop control system is used for satisfying the system demand. According to the special working condition of Sea Robot and the characteristic of BLDCM, fuzzy-PID algorithm is used to speed loop and PI algorithm is used to current loop. The fuzzy-PID controller, which can regulate control parameter according to the current state of controlled object, can satisfy the dynamic change of motor. Then the fuzzy control system is designed and simulated. The result of simulation shows that the adoption of fuzzy-PID controller can make the system have better performances, such as quicker response, smaller overshoot and better stability, relative to the classic PID controller.Secondly, according to the reliability and volume demand of the sea-robot's drive system, the TMS320LF2407A is chosen as the control chip of the drive motor. It has the high integration and quick operating speed. The control system,which has few periphery electric circuit and quicker operating speed,can enhance the reliability and the real-time control ability of the whole system.According to the characteristic of BLDCM and the function of the chip, sensor control solutions which are based on DSP technology are presented.At last, the hardware and software design of the system according to the preceding solution are discussed in detail. For the hardware part, after a instruction of the whole design, the design of several chief circuits is presented. For the software part, some procedure flow charts of main program are offered and some problems of software realization are researched. Especially, the realization of fuzzy-PID algorithm is introduced. At last, the testing waveform when the control system running is observed and the results are analyzed.