What is the purpose of the hoop on the rotor?

The cast aluminum rotor of a conventional motor is a relatively solid unit, while the wound rotor motor is not. Whether it is a hard or a soft winding, the winding end is relatively weak.

In order to circumvent this problem, in addition to the curing of the immersion paint of the winding, another measure taken is to increase the bearing pressure ring at the end of the winding to ensure that the spatial distance of the end portion relative to the shaft meets the requirements, and then will be outside the end of the rotor winding. The heat-shrinkable tie wrap is looped to control the rotor winding to deform radially outward.

After the rotor end is tied to the rotor weaving line, it is carried out before the varnishing. After the subsequent dipping and drying process, the binding tape shrinks and is tightly matched with the winding in the radial direction, and can be integrated with the winding through the insulating varnish, so that the rotor is reliable. Sex has been enhanced.

For the wound rotor motor, the speed of the motor must be strictly controlled, because it is likely to occur when the overspeed is running, that is, the end of the rotor winding is deformed outward and rubbed against the rotor winding, causing a devastating electrical failure of the motor.

What is the bag fault of the motor rotor?

The bag is a unique fault of the wound rotor motor. It is caused by the overspeed of the motor. This type of fault is mostly caused by the winch and the running condition during the running. The fault is manifested by the deformation of the rotor winding end and higher than the rotor core. Path, this problem will cause the stator winding to be damaged and burned.

The bag failure is fatal to the motor and can be effectively avoided by the speed limit protection device. During the production and processing of the motor, necessary fixing measures should be taken at the end of the rotor winding of the motor to prevent deformation of the end.

Measures taken during the production process

In order to strengthen the end rigidity and reliability during the production process, the necessary measures include:

● Support, hoop tight. The bracket and the end clamp are added at the end of the rotor to overcome the radial centrifugal force of the rotor winding, and the winding is prevented from being deformed by heat when the motor is running.

● The elastic strap is fixed. The PST elastic strap is fixed outside the end of the winding to fix the winding to a solid whole. During the motor dipping process, the PST is heat-shrinked, which ensures the curing reliability of the rotor end.

● The varnish is cured. Similar to the stator winding process, the VPI dip coating process is used to greatly improve the mechanical strength and insulation reliability of the winding.

● Rotor dynamic balance. Strictly control the dynamic balance accuracy of the rotor, reduce and eliminate the damage of the alternating rotor excitation force to the rotor winding.


It is important to note that during the production and processing of the motor, the manufacturer will perform a 1.2-fold overspeed test on the motor to verify the robustness of the rotor end. The technical conditions of the motor will also be specified; but the most effective method is that the customer must Know the requirements in this regard and take the necessary measures.