Brushless DC motor and drive by the motor body composition, is a typical mechatronics product.Motor stator winding multiple made symmetrical three-phase Y connection, with the three-phase asynchronous motor is very similar. The rotor of the motor is affixed is magnetized permanent magnet motor rotor, in order to detect the polarity, in a motor with position sensor. Drive by power electronic devices and integrated circuit components, its function is: accept motor start, stop, brake signal, in order to control motor's start, stop and brake; accept the position sensor signal and a normal-reverse signal, used to control the inverter the power tube on-off, continuous torque; accept the speed command and velocity the feedback signal, used to control and adjust the speed; provide protection and display etc..As a result of Brushless DC motor with automatic operation, so not as variable frequency speed control of heavy load starting of synchronous motor in rotor plus the start winding, nor in the mutation load is generated when oscillation and.Small brushless DC motor permanent magnet with high energy product, now uses the rare earth neodymium iron boron ( Nd-Fe-B ) material. Therefore, the rare earth permanent magnet brushless motor volume than the same volume of three-phase asynchronous motor narrowing of a frame.Come nearly thirty years for asynchronous motor variable frequency speed control research, in the final analysis is looking for control asynchronous motor torque method, rare earth permanent magnet brushless DC motor is bound to its wide speed, small volume, high efficiency and steady speed error is small wait for a characteristic in the control field is showing its advantage.Brushless DC motor with brush DC motor characteristics, but also the frequency changing device, so that a DC inverter, the international generic noun BLDC. Brushless DC motor operation efficiency, the torque at low speed, speed precision than any control technology of converter drives, so worthy of concern. This product has production with over 55kW, can be designed to 400kW, can solve the industry of energy saving and high performance driving demand.