SYSTEM AND METHOD FOR ESTIMATING ELECTRICAL CURRENT IN MOTOR CONTROL CIRCUITS TO IMPROVE PERFORMANCE AND DIAGNOSTIC CAPABILITY

摘要

An error condition detection circuit coupled to the motor control circuit reports an error condition when actual motor operation deviates from predetermined desired motor operation. An overcurrent threshold comparator compares motor current with a threshold data value stored in a data storage register, and sets an overcurrent flag when the motor current exceeds the threshold. A current interrogation processor monitors the reported error condition and is programmed to respond to the error condition by iteratively reading the overcurrent flag and decrementing the overcurrent threshold data value by a predetermined decrement amount until the overcurrent flag becomes set. The current interrogation processor is further programmed to report the overcurrent threshold data value extant at the time the flag becomes set as an estimate of electric current.