| 摘要 |
PROBLEM TO BE SOLVED: To perform overheat protection for a plurality of protection objects or temperature compensation together with the overheat protection without increasing the number of temperature sensors, in an electric power steering device. SOLUTION: An atmosphere temperature arithmetic part 16 calculates an atmosphere temperature estimated value Ta by subtracting a temperature rising part of a temperature sensor 21 calculated based on a motor driving current detected value Is from a temperature detected value T of the temperature sensor 21. An overheat protection arithmetic part 17 calculates temperature estimated values of the plurality of overheat projection objects based on the atmosphere temperature estimated value Ta (or the temperature detected value T) and the motor driving current detected value Is and determines an upper limit value ILim of target current driven by a motor based on the temperature estimated values. A temperature compensation arithmetic part 18 calculates a temperature compensation current valueΔI<SB>Tc</SB>to be added to a target current value It for compensating a temperature characteristic at a prescribed portion. COPYRIGHT: (C)2006,JPO&NCIPI |
