Zd Series Industrial Use Separately Excited Brushed 1 HP DC Electric Motor

01 About the noise of the motor

The noise of the motor is divided into mechanical noise, electromagnetic noise and ventilation noise. According to the generation mechanism of vibration and noise, we can also classify the vibration of the motor correspondingly, but in most cases, noise and vibration are a comprehensive Performance.

Electromagnetic noise is a kind of noise generated by the magnetic field pulsation in the motor gap, which causes the vibration of the stator, rotor and the entire motor structure. Its value depends on the electromagnetic load and the design parameters of the motor. Electromagnetic noise is mainly structural noise, which is divided into constant electromagnetic noise and load-related magnetic noise. Electromagnetic noise has high-frequency screaming and low-frequency booming.

Mechanical noise is the noise caused by friction, impact, unbalance and structural resonance of the running part of the motor. There are many types of noise caused by mechanical reasons, and they are also very complex. Noise sources mainly include self-noise sources, load-induced noise sources, and mechanical noise sources of auxiliary components. It comes down to the problems of processing technology, processing accuracy, and assembly quality. Generally produced by brushes and commutators, bearings, rotors, ventilation systems, etc. Mechanical noise can generally be summarized as noise around brushes (only for brushed motors), bearing noise, fan noise, load noise, etc.

Judging the type of noise adopts the method of cutting off the power supply. Using the characteristics of electromagnetic noise that changes with the strength of the magnetic field, the magnitude of the load current and the level of the speed, the power is suddenly cut off after listening to the motor running at no-load for a period of time. With the power cut off, part of the noise will disappear immediately, this is electromagnetic noise. After a power failure, the noise generated by the motor continuing to run by inertia is mechanical noise and ventilation noise.