Study On A Networked BLDC Motor Driver

As one of the most important acuators of speed regulation and position control system, Brushless Direct Current(BLDC) Motor has achieved a wide application in many fileds, such as aerospace, automobile, industrial automation, medical equipments, home appliances, etc. Aiming at the trend of networking and intelligentization, key techniques and implementations of BLDC Motor driver are discussed in detail, including hardware architecture, embedded system firmware, bus communication and control loop self-tuning. The main contributions are as follows:The hardware architecture is introduced. The main processor is LM3S8971, a 32 bit MCU based on Cortex-M3. Main circuits designs are provided, including power module, minimum system, communication interface, motor control module, I/O module and safety module. A prototype is also implemented based on above designs.The firmware is developed, with the function of motor driving and safety monitoring. Lw IP transplantation and TCP server implementation are introduced. The data application protocol is specified based on Modbus/TCP.The control loop tuning technique is studied. A BLDC Motor control system with double closed-loop is modeled on Matlab/Simulink. The Engineering Design Method is carried out for the tuning of current loop and speed loop. The control effect of the tuning results are evaluated through the model simulation.The monitoring and tuning software with Ethernet & Modbus/TCP support is developed. Its function includes on-line monitoring, driver parameters management and control loop self-tuning based on the Ziegler–Nichols Method and the Engineering Design Method.The prototype debugging is carried out on an inertia identification experiment platform and a tri-axial Cartesian coordinate platform. The results show that the design is feasible and practical.