Study On Control System Of Permanent Magnet Sensorless And Brushless DC Motor

With the rapid development of power electronic technology and high performance magnetic materials, Permanent brushless DC motor is the new one which has won the rapid development and wide application, it not only has the traditional DC motor good and fast speed characteristics, but also has simple structure, reliable operation, easy controlling, convenient maintenance and long service-life etc. The application rapidly overspreads from initial military industry to the aerospace, medical treatment, information and industrial automation.As the reason of the inherent characteristics of brushless DC motor, conventional controlling methods must have the position sensor making complex structure.Finally, it can affect the operation reliability and increased costs, what's more, it is not convenient to use this device in complex industrial environment. Therefore, the sensorless and brushless DC motor drive system is particularly important.This topic design,control system of permanent magnet sensorless and brushless DC motor, ensure and enhance their control under the premise of precision and performance by relatively low cost, and excellent performance of single chip microcomputer as control core. Through the drive inverter circuits, it can be accurately controlled in speed range. Motor conduction instead potential not detection, by the voltage comparator to complete, avoids directly using AD transform and improves the executing speed of the MCU. In order to guarantee the security of system working, the circuit must be monitored instantaneously.As only as the current exceeds the maximum, it warns the systems and makes inverter circuits closed. In order to be intuitive, the system adopts LCD model, which can instantaneously display motor speed and current steering etc.The system can better meet company and the needs of the market with better controlling effects under the actual commissioning.