Is the difference between the motor and brushless motor speed control mode in fact two motor control are regulating, just because of the brushless dc adopted electronic commutation, so have the digital control can be realized, and a brush dc is through the carbon brush, using traditional analog circuit can control, such as the silicon controlled rectifier is straightforward. , has a brush motor speed control process is to adjust the motor power supply voltage. After adjusting the voltage current transformation through commutator and brush, change the electrode produce the magnetic field strength, achieve the goal of changing speed. This process is called 'variable voltage speed regulation. Is motor, brushless motor speed adjustment process of power supply voltage is constant, change the electrical control signal, through the microprocessor to change switch rate of high-power MOS tube, to realize the speed change. This process is called 'frequency control of motor speed. Performance difference, brush motor has simple structure, long development time, mature technology in the early nineteenth ji was born motor, the practicality of the motor is a brushless forms, namely ac squirrel-cage asynchronous motor, the motor on the alternating current (ac) has been widely used in the future. But asynchronous motor has many not be able to overcome the defects, so that the slow development of motor technology. Especially the brushless dc motor has been unable to commercial operation, along with electronic technology with each passing day, until slowly into commercial operation in recent years, in terms of its essence still belong to the category of ac motor. Brushless motor was born before long, people invented a dc motor. Because of a dc motor is simple, production and processing is easy, convenient maintenance, easy to control; Dc motor has rapid response, large starting torque, rotating speed of from zero to rated speed can provide the rated torque performance, so is widely used as it comes. , the response of a dc motor speed, starting torque with dc motor starting fast response speed, large starting torque, smooth speed, speed from zero to maximum almost feel vibration, the start will lead to more of the load. Brushless motor starting resistance (Impedance), so the power factor is small, relatively small starting torque, starting with buzz, and with the strong vibration, starting when the driving load is smaller. , a dc motor smooth operation and good effect has a brush motor starting and brake is through regulating speed, so the smooth starting and braking, constant speed operation is stable. Brushless motor is usually a digital frequency conversion control, first the ac into dc, dc to ac again, controlled by frequency variation speed, so the brushless motor during starting and braking running is not smooth, vibration is big, only in constant speed smoothly. , a dc motor control precision have a dc motor and reducer, usually the decoder are used together, make the motor output power is bigger, higher control precision and control precision can be achieved. Mm, almost can make the moving parts parking place in any desired. All precision machine tool is the dc motor control precision. Brushless motor because at the time of starting and braking is not smooth, so the moving parts will stop to each different position, must through the locating pin or stop can be parked in the position of want. , a dc motor using the low cost and easy maintenance. With a brush dc motor has simple structure, low production costs, manufacturers, technology is mature, so also more widely used, such as factories, machine tools, precision instruments, etc. , if the motor fault, simply replace carbon brush, each carbon brush it only takes a few yuan, very cheap. Brushless motor technology is not mature, the price is high, application scope is limited, should be mainly on constant speed equipment, such as frequency conversion air conditioning, refrigerator, brushless motor damage can only be replaced. Brushless motor, brushless, low interference to in addition to the brush, the most immediate change is without the motor running when the electric spark, thus greatly reduce the electric spark interference of remote radio equipment. Smooth operation, low noise, brushless motor without brush, less friction force during operation, smooth operation, low noise will be many, the advantages of model operation stability is a huge support. , long life, low maintenance costs less brush, brushless motor wear is mainly on the bearing, from the mechanical point of view, brushless motor is almost a maintenance-free motor, when necessary, the only need to do some cleaning maintenance.
