| 摘要 |
PROBLEM TO BE SOLVED: To expand a range of application of a motor and prevent an excessive overheating protection from being applied to the motor. SOLUTION: This electric power steering system comprises a motor temperature estimating segment 30 for estimating a temperature of a motor 10, a motor rotation detecting segment 24 for detecting a rotational speed of the motor 10, an overheating protection correcting segment 28 for judging whether or not the motor 10 keeps rotated or locked in reference to the rotational speed of the motor 10 and for correcting the motor temperature estimated value in response to a result of this discrimination and a motor current command segment 12 for controlling a driving state for the motor 10 in response to the generated motor current command value. The overheating protection correcting segment 28 corrects the motor temperature estimating value lower than that attained when the motor 10 is kept at its locked state under a condition in which the motor 10 is in its rotating state and prevents the excessive overheating protection control from being carried out. COPYRIGHT: (C)2009,JPO&INPIT |
