What should you pay attention to when purchasing a brushless DC motor

Brushless DC motor is a semiconductor switching device to realize electronic commutation, that is, using electronic switching devices instead of the traditional contact commutator and brushes. It has the advantages of high reliability, no commutation sparks, low mechanical noise, etc. It is widely used in high-grade recording seats, video recorders, electronic instruments and automated office equipment.
Brushless DC motor consists of permanent magnet rotor, multi-pole winding stator, position sensor and so on. Position sensor according to changes in rotor position, along a certain order of the stator winding current for current exchange (i.e., detecting the rotor magnetic pole relative to the position of the stator winding, and in the determined position at the location of the location of the sensing signals generated by the signal conversion circuit to control the power switching circuit, according to a certain logical relationship between the winding current switching). Work of stator winding.
Which aspects do I need to start with when buying a DC brushless motor? What issues should be noted? The following Demark motor will give you an introduction to one or two, in the purchase of DC brushless motor selection may wish to compare and see if it is useful.
1. Pay attention to the voltage of brushless DC motor
Voltage is provided by the electronic switching circuit controlled by the output of the position sensor. Selection of brushless DC motor products should first choose the correct voltage, according to the customer's needs to select the rated voltage to select the drive voltage parameters, pay attention to the use of voltage in the no-load and full-load process do not exceed the range specified by the drive.
2. Pay attention to the current of the brushless DC motor
Let's choose the peak current of the drive, the method of selecting the peak current is already the rated input current of the motor Ir (A), then the peak current Ip (A) = 2xIr, otherwise the drive is used in the process of the output current does not have a certain amount of engineering margins, if the motor is known to be the rated output power (or the highest output power) Pr (W) and the drive voltage Vr (V), then the peak current Ip (A) ≧ 4xPr/Vr. 4xPr/Vr.
3. Pay attention to the use temperature of the brushless DC motor.
We can also set the motor according to the parameters, but we need to set it according to different motors to set the appropriate parameters, of course, the temperature of the use of the range we also need to take into account, the wider the temperature the higher the price.
4. Pay attention to the resistance of the brushless DC motor
According to the requirements of power insulation, in order to ensure the normal operation of the drive, the motor hall line ground and motor winding line, hall ground winding line and chassis insulation resistance between the line is greater than 100 megohm 500VDC, can withstand 600VAC/50Hz/1mA/1 second withstand voltage does not break down.
Special Note: The braking of DC brushless motor adopts short-circuit braking at the motor end, there is braking force when the motor is running, and there is no braking force when it is not running, and the higher the rotational speed is, the greater the braking force is. Since the brake current does not pass through the current sensing resistor, the brake current cannot be controlled. Therefore, the braking speed can not exceed the safe braking speed, otherwise it may burn out the power tube, please use this function with caution.