Systems and methods for motor parameter extraction
AssigneeAnalog Devices International Unlimited Company
InventorsAdam James Glibbery, Javier Calpe Maravilla
Life of this patent
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Abstract
Systems and methods for extracting motor operational state parameters from an electric motor for improved motor control and motor fault or failure detection are discussed. An exemplary system includes an excitation circuit to apply a drive voltage to an electric motor, and a processor circuit to measure a resulting winding current, extract a current waveform by oversampling the winding current in an entire PWM frame at a sampling rate higher than the PWM frequency, and fit the current waveform in the PWM period to a parametric model. The processor circuit can determine a motor operational state parameter using one or more of the applied drive voltage or the parametric model of the winding current.
Claims25
A system for monitoring an operating condition of an electric motor that includes a stator and a rotor, the system comprising:
- an excitation circuit configured to apply a drive voltage to the electric motor;
- and
- a processor circuit configured to:
- measure a winding current from the electric motor in response to the applied drive voltage;
- generate a parametric model to simulate the winding current;
- and
- determine at least one parameter of an operational state of the electric motor using the parametric model.
A method of monitoring an operating condition of an electric motor that includes a stator and a rotor, the method comprising:
- applying a drive voltage to the electric motor;
- measuring a winding current from the electric motor in response to the applied drive voltage;
- generating a parametric model to simulate the winding current;
- and
- determining at least one parameter of an operational state of the electric motor using the parametric model.
A system for monitoring an operating condition of an electric motor that includes a stator and a rotor, the system comprising:
- an excitation circuit configured to apply a drive voltage to the electric motor, the drive voltage including a pulse-width modulation (PWM) voltage having a voltage-switching edge representing a transition of a voltage level applied to the stator;
- and
- a processor circuit, including:
- an analog filter configured to filter the drive voltage;
- an analog-to-digital converter configured to sample the filtered drive voltage during a PWM period at a sampling rate higher than a PWM frequency;
- and
- a digital filter configured to inverse-filter the sampled drive voltage;
- wherein the processor circuit is configured to generate an average drive voltage using the inverse-filtered digitized drive voltage in the PWM period, and to determine at least one at least one parameter of an operational state of the electric motor using the average drive voltage in the PWM period.
A system for monitoring an operating condition of an electric motor that includes a stator and a rotor, the system comprising:
- an excitation circuit configured to apply a drive voltage to the electric motor;
- and
- a processor circuit configured to:
- measure a winding current from the electric motor in response to the applied drive voltage;
- determine at least one motor operational state parameter using one or more of the applied drive voltage or the measured winding current;
- and
- estimate a rotor angle using the applied drive voltage, the measured winding current, and the determined at least one motor operational state parameter.
Dependencies are inferred from the claim text.