The brake motor is a three-phase asynchronous motor with an additional disc type DC brake. It is composed of a DC disc type electromagnetic brake motor between the top cover of the y series motor and the fan. It is very convenient to use the brake motor to control the start and stop of the operation. It is widely used in metal processing machine tools, packaging machinery, woodworking machinery, food machinery, chemical machinery, textile machinery, engineering machinery and gear reducers, etc., which require quick shutdown and correct positioning. Kind of mechanical equipment and drives.

When some unexpected accidents occur during the work of the machine, the brake motor can help us stop the operation of the machine in time, and relatively reduce the severity of the accident. Common brake motors generally have two operating principles. One is to energize the coil to release the lock to make the motor run. When the motor stops, the brake coil is cut off and the brake coil is automatically tightened; the other is to stop the motor. At this time, the winding applies a strong magnetic brake through the current of the brake motor control circuit.

During the debugging process of the inverter of the brake motor, if the motor speed exceeds its rated operating frequency, it may produce noise during operation. The main reasons are as follows:

1. Make clear whether there is a filter device in the brake motor

The soft start output contains a lot of higher harmonics instead of sine waves. Under the action of higher harmonics, the motor will generate more heat and be accompanied by abnormal sounds. However, after adding a filter to the brake motor, the soft-start output is a sine wave, and the abnormal noise and heat will be reduced a lot.

2. The speed of the general brake motor shall not exceed 1.2 times the rated value

For example, one of the technical standards of general y series brake motor products is that when the motor is fully loaded, the speed will be increased to 1.2 times the rated value for more than 2 minutes, which will cause harmful deformation. The speed of the DC frequency conversion special brake motor is one to several times higher than the rated speed, which will cause the temperature of the motor to rise due to the high frequency, which will expand the vibration and increase the load of the roller, which will have a negative impact on the life of the motor.

In fact, the "hum" we often say is caused by the carrier frequency of the inverter's output waveform. Generally speaking, if the inverter you use is a fixed carrier, the motor will make a noise. In this case, we can improve the situation by adjusting the carrier frequency.