Method for the detection of abnormalities of electric motors

• US 20050092105A1
• Filed: 01/15/2003
• Published: 05/05/2005
• Est. Priority Date: 02/13/2002
• Status: Active Grant

• Current Assignee: Continental Teves AG & Co. OHG (Continental AG)
• Original Assignee: Continental Teves AG & Co. OHG (Continental AG)
• Inventors: Feick, Stefan
• Granted Patent: US 7,385,365 B2
• Time in Patent Office: Days
• US Class Current: 73/862.08
• CPC Class Codes: H02P 29/02 Providing protection against overload without automatic interruption of supply protection against faults of stepper motors H02P8/36
• CPC Class Codes: H02P 6/34 Modelling or simulation for control purposes

Abstract

In a method for error detection of a brushless electric motor, at least one first motor parameter is measured or determined, and a second, estimated motor parameter is estimated on the basis of the first motor parameter. The second, estimated motor parameter is compared to a second, measured or determined motor parameter. An error of the electric motor can be found out according to the comparison.

Claims

1-8. -8. (canceled)

9. Method for error detection of a brushless electric motor,

wherein at least one first motor parameter is measured or determined, and a second, estimated motor parameter is estimated on the basis of the first motor parameter, in that the second, estimated motor parameter is compared to a second, measured or determined motor parameter, and an error of the electric motor is found out according to the comparison.

10. Method as claimed in claim 9,

wherein the second, estimated motor parameter is estimated on the basis of a model.

11. Method as claimed in claim 9,

wherein an estimated current producing a motor torque and a quantity derived therefrom is estimated as a second, estimated motor parameter and compared with a nominal current producing a motor torque or a quantity derived therefrom as a second motor parameter.

12. Method as claimed in claim 9,

the method further comprising an estimated current producing a motor torque and a quantity derived therefrom is estimated as a second, estimated motor parameter and compared with a nominal current producing a motor torque or a quantity derived therefrom as a second motor parameter,

wherein the estimated current producing the motor torque or the quantity derived therefrom is estimated on the basis of at least one phase motor current and the rotor position or phase position of the electric motor.

13. Method as claimed in claim 9,

the method further comprising an estimated current producing a motor torque and a quantity derived therefrom is estimated as a second, estimated motor parameter and compared with a nominal current producing a motor torque or a quantity derived therefrom as a second motor parameter,

and the estimated current producing the motor torque or the quantity derived therefrom is estimated on the basis of at least one phase motor current and the rotor position or phase position of the electric motor,

wherein the absolute rotor position or phase position relative to a stator of the electric motor is defined by measuring the respective actual phase position variation of the rotor relative to the stator and determining the absolute phase position therefrom.

14. Method as claimed in claim 9,

the method further comprising an estimated current producing a motor torque and a quantity derived therefrom is estimated as a second, estimated motor parameter and compared with a nominal current producing a motor torque or a quantity derived therefrom as a second motor parameter,

and the estimated current producing the motor torque or the quantity derived therefrom is estimated on the basis of at least one phase motor current and the rotor position or phase position of the electric motor,

wherein the phase currents are estimated on the basis of phase voltages in consideration of induced countervoltages proportional to rotational speed.

15. Method as claimed in claim 9,

the method further comprising an estimated current producing a motor torque and a quantity derived therefrom is estimated as a second, estimated motor parameter and compared with a nominal current producing a motor torque or a quantity derived therefrom as a second motor parameter,

wherein the temperature of the electric motor and/or the windings of the electric motor is measured and also taken into consideration in the estimation of the estimated currents.

16. Method as claimed in claim 9,

wherein an error is detected according to a comparison between the requested torque of the brushless electric motor and the current consumption of an end stage that actuates the electric motor.