Dalan Motor describes 10 knowledge points of insulation in the special motor of hydraulic oil pump, you don't necessarily know it!

Regarding the problem of the motor insulation for the hydraulic oil pump, Dalan Motor Xiaobian said and said that it is important. Today, Xiaobian will bring you to learn more about the related knowledge of motor insulation, and learn from everyone.

1. The current in the insulation consists of three parts:

Instantaneous charging current: generated by the displacement polarization of the geometric capacitance of the medium, gradually decaying with time, expressed as ic.

Absorption current: generated by slow polarization, volume charge generated by conductive ions, etc., also gradually decays with time, expressed by ia.

Leakage current: The magnitude of the leakage current is closely related to the amount of ions in the insulating material itself, expressed in ib.

Second, the insulation resistance

The quotient of the dc voltage applied between the two electrodes in contact with the insulator or sample divided by the total current through the two electrodes.

Third, the volume resistance

The dc applied between the two electrodes placed on opposite sides of the sample divided by the steady state current formed between the two electrodes; that is, the electrical resistance between the opposite surfaces of the insulating material.

Fourth, volume resistivity

The quotient of the DC electric field strength in the sample divided by the steady state current density can be seen as a volume resistance in one cubic volume. The volume resistivity of insulating materials is usually between 109 and 1021 WNaN.

Fifth, the surface resistance

The quotient of the DC voltage applied between the two electrodes on the same surface of the insulator or sample divided by the current between the two electrodes after a certain electrochemical time.

Sixth, surface resistivity

The quotient of the DC electric field strength at the surface of the insulating material divided by the current line density.

7. Factors affecting resistivity: temperature, humidity, impurities, electric field strength.

Eight, dielectric

Under the action of an electric field, all substances that are polarized can be established. The insulating material is one of the dielectrics.

9. Polarization of the dielectric

Under an external electric field, the surface of the dielectric generates an induced charge (bound charge) called polarization of the dielectric.

Ten, the basic form of dielectric polarization

Displacement polarization, relaxation polarization, steering polarization, space charge polarization, spontaneous polarization.




----- Editor-in-Chief: Dalan Oil Pump Motor 02-Procurement Consultant

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