US 2022/0069752 A1 · METHOD OF DETECTING CONNECTION FAULT OF ELECTRIC MOTOR

Abstract

A method of detecting a connection fault of an electric motor, applies to a driving mechanism of an inverter, and includes: measuring a three-phase stator current of the electric motor; transforming the three-phase stator current to acquire dual-axis current components in a stationary coordinate; calculating an angle of rotation of the electric motor according to the dual-axis current components; calculating an angular velocity according to the angle of rotation; comparing a frequency of the angular velocity with a frequency of an output voltage of the inverter; and determining that the electric motor occurs a connection fault if a difference between the frequency of the angular velocity and the frequency of the output voltage is greater than a predetermined frequency difference value.

Claims10

Dependent claims

A method of detecting a connection fault of an electric motor applied to an open-loop driving mechanism of an inverter, the method comprising:

measuring a three-phase stator current of the electric motor;
transforming the three-phase stator current to acquire dual-axis current components in a stationary coordinate;
calculating an angle of rotation of the electric motor according to the dual-axis current components;
calculating an angular velocity according to the angle of rotation;
comparing a frequency of the angular velocity with a frequency of an output voltage of the inverter;
and
determining that the electric motor occurs a connection fault if a difference between the frequency of the angular velocity and the frequency of the output voltage is greater than a predetermined frequency difference value.

4 more elements

A method of detecting a connection fault of an electric motor applied to a closed-loop driving mechanism of an inverter, the method comprising:

measuring a three-phase stator current of the electric motor;
transforming the three-phase stator current to acquire a plurality of axis current components in a stationary coordinate;
acquiring dual-axis current commands of the inverter in a synchronous coordinate;
transforming the dual-axis current commands to acquire a plurality of axis current commands of the inverter in the stationary coordinate;
and
comparing the plurality of axis current commands in the stationary coordinate and the plurality of axis current components in the stationary coordinate to acquire a plurality of axis current error values in the stationary coordinate, and determining that the electric motor occurs a connection fault if any of the plurality of axis current error values is greater than a predetermined current difference value.

3 more elements

Dependencies are inferred from the claim text.

Method of detecting connection fault of electric motor

Life of this patent

Method of detecting connection fault of electric motor

Life of this patent

Abstract

Claims10