BLDC Motor Rated Load Range

BLDC Motor Rated load range


DC brushless motor is a synchronous motor, which means that the motor rotor speed by the motor stator rotation of the magnetic field and the number of rotor (p):

N = 60. F / p. In the case of a fixed number of rotors, changing the frequency of the stator's rotating magnetic field can change the rotational speed of the rotor. DC brushless motor is the synchronous motor with electronic control (drive), control the stator rotation magnetic field frequency and the motor rotor speed back to the control center repeated correction, in order to achieve close to the DC motor characteristics of the way. That is, DC brushless motor can be in the rated load range when the load changes can still control the motor rotor to maintain a certain speed.

DC brushless drive includes the power supply and the control part: the power supply department to provide three-phase power to the motor, the control unit will be converted according to the needs of input power frequency.

The power supply unit can be directly DC input (usually 24v) or AC input (110v / 220v), if the input is AC must first converter (converter) into DC. Either DC input or AC input to be transferred to the motor coil before the DC voltage from the inverter (inverter) into three-phase voltage to drive the motor. Inverter (6) is connected to the upper arm (q1, q3, q5) / lower arm (q2, q4, q6) to control the flow through the motor coil. The control section provides pwm (pulse width modulation) to determine the power transistor switching frequency and inverter (inverter) commutation timing. DC brushless motors generally want to use when the load changes in the speed can be stabilized at the set value without changing the speed of control, so the motor is equipped with a magnetic field inside the hall sensor (hall-sensor), as the speed Closed loop control, but also as a basis for phase control. But this is only used as a speed control and can not be used as a positioning control.


1, can replace the DC motor speed, inverter + inverter motor speed, asynchronous motor + reducer speed;

2, with the advantages of traditional DC motor, while eliminating the carbon brush, slip ring structure;

3, can be low-speed high-power operation, you can save the reducer directly drive large load;

4, small size, light weight, the output of large;

5, excellent torque characteristics, medium and low torque performance, start torque, start the current is small;

6, stepless speed regulation, wide speed range, overload capacity;

7, soft start soft stop, good braking characteristics, can save the original mechanical brake or electromagnetic brake device;

8, high efficiency, the motor itself does not have the excitation loss and carbon brush loss, eliminating the multi-level deceleration, the integrated energy-saving rate of up to 20% to 60%.

9, high reliability, good stability, strong adaptability, maintenance and maintenance simple;

10, resistant to bumpy vibration, low noise, small vibration, smooth operation, long life;

11, does not produce sparks, especially for explosive places, explosion-proof;

12, according to the need for optional trapezoidal wave field motor and sine wave magnetic field motor.