| 摘要 |
PROBLEM TO BE SOLVED: To provide a device for estimating the number of revolutions of an electric motor, which can estimate the number of revolutions of a motor with accuracy, without raising the cost, by correcting the error based on the temperature change without needing complicated control. SOLUTION: A motor revolution estimating circuit F built in a microcomputer A estimates the number of revolutions ω(estimate EOMG) of a motor univocally by the approximate expression for getting the number of revolutions of the electric motor M where the change of a voltage value VOLT and the change of the temperature ROTT are taken into consideration, from the voltage value VOLT applied to the electric motor detected with a voltage detection circuit E, the temperature ROTT of the motor M detected with a temperature sensor TES, and the torque T of the electric motor M detected with a torque detection means TS2. |
