SOLENOID TEMPERATURE ESTIMATING DEVICE

摘要

PROBLEM TO BE SOLVED: To enable the temperature of a linear solenoid for hydraulic control more to be estimated accurately from an ambient temperature (oil temperature). SOLUTION: An oil temperature Toil is detected by an oil temperature sensor (S1). A solenoid current Isol is detected by a current sensor (S2). A heat generating value equivalent valueΔT is obtained from the solenoid current Isol in reference to a table (S3). The oil temperature Toil is determined (S4). In the case of a high-temperature region, the solenoid heat generating value equivalent valueΔT is added to the oil temperature Toil to compute the solenoid temperature Tsol=Toil+ΔT (S5). In the case of a low-temperature region, a predetermined value Tc is subtracted from the oil temperature Toil to compute the solenoid temperature Tsol=Toil-Tc (S6).