Stall detection in stepper motors
AssigneeDresser, Inc.
InventorMartin Graham Wiseman
Life of this patent
Estimating the term…
Abstract
A stall detection method and system for a stepper motor ascertains a stalled condition according to current rise time of the windings. The motor is determined to be in a normal running condition when current rise time of opposed windings is substantially constant, including monotonic increases and monotonic decreases, in cycles of the rotor. The motor is determined to be in a stalled condition when the current rise time of opposed windings has a relative short-long pattern.
Claims17
A method for detecting whether a stepper motor is running or stalled, the stepper motor having a rotor and a plurality of energizable stator windings, the method comprising:
- determining that the stepper motor is stalled based on a current rise time of the windings.
A stall detection system for a stepper motor, the stepper motor having a rotor and a plurality of energizable windings, the system comprising a device that ascertains a running condition of the motor when the current rise times of all the windings in the motor are substantially equal within a cycle of the motor and a stalled condition of the motor when the current rise times of one winding is relatively short as compared to a winding opposite the one winding within a cycle of the motor.
Dependencies are inferred from the claim text.