The Permanent Magnet Brushless Dc Motor Design, Low-speed Synchronous Motor Applications

This thesis presents two parts of content, one part is application system design on permanent magnetic brushless DC motor and the other is on low speed synchronous motor. Two parts go into detail about design requirements, design idea, hardware, software and etc. Experimental oscillogram and test data are given at the last chapters of two parts in order to testify validity and feasibility of system application.Application system of permanent magnetic brushless DC motor utilizes MCU-AT89C52 and brushless DC motor controller-MC33035 to closed-loop control on brushless DC motor. As a result, motor speed can be adjustable from 10rpm to 2200rpm. Application system is able to detect some errors in motor' s run, such as over-voltage, under-voltage, over-current, over-loading and stalling, and execute measures to protect motor from being damaged. Over-voltage and under-voltage protection is implemented by hardware and over-current protection is by MC33035 component inside protective function. Both hardware and software carries out over-loading and stalling protection. This thesis also theoretically presents software design idea on motor over-loading and stalling protection. Above measures help brushless DC motor run more safely and reliably and perfect the entire application system.Application system of low-speed synchronous motor uses principal and subordinate control mode. Personal Computer as a master controller can communicate with DSP device as a slave controller in virtue of COM port. Master can send orders to slave and receive information from slave. Slave control system adopts TI digital signal processor-TMS320LF2407A and does orientation and position-estimate to 12 low-speed synchronous motors with GAL interface. On the base of mathematical model of cam mechanism, the thesis does strict deduction and finds relation between shaft elevating angle and mechanical angle of low-speed synchronous motor. Software in DSP2407A relates calculating-time of voltage- current phase difference to mechanical angle of synchronous motor. At last application system does approximate estimate to cam position depending on three variable relations.