has spread invarious fields of national economy and people in their daily life.
Traditional DC motor brushes, mechanical method of commutation, there is a
relatively mechanical friction, which bring about the fatal weakness of noise, sparks,
radio interference, and short life, manufacturing high cost and maintenance difficulties
and shortcomings. thus greatly limiting its scope of application. The permanent magnet
brushless DC motor is rapidly maturing in recent years with the development of power
electronic devices and new permanent magnetic materials up a new the mechatronics
motor, it has the following characteristics:
1. The rotor of the brushless DC motor with high energy product rare earth magnet as
the rotor magnet, the squirrel cage rotor inertia ratio is smaller, so for a given torque
can respond faster to control features better.
2. The efficiency of the brushless DC motor is higher than the induction
motor.Because the induction motor is running, the rotor does not produce the copper
loss and iron loss.
3. In the same capacity, the volume of the brushless DC motor is relatively better than
the induction motor is small, light weight.
4. Brushless DC motor noise.
5 Brushless DC motor speed convenient, flexible, and a wide range of

initial complex analogue to the recently digital microcontroller as the core, but the new
motor control ASIC, brushless DC motor speed control device design a great
convenience, integrated analog control chip controlling function, the protection
function, stable performance, simple system composed of the peripheral circuits
required, and strong anti-jamming capability, especially suitable for volume controller,
the performance requirements higher occasions. Advantages of a dedicated control
chip of course, but often are expensive. In the occasion of some control accuracy is not
high, you need to be able to have a working stability, price and relatively low-cost
controller. This design is based on market demand.