| 摘要 |
PROBLEM TO BE SOLVED: To provide an onboard relay control device capable of reliably preventing occurrence of dew formation and freezing at the time of disconnecting an onboard relay, and an electric power steering system using the onboard relay control device.SOLUTION: An onboard relay control device includes in a package an actuator drive circuit that drives an onboard actuator, an onboard relay inserted into at least one of a power feed path to the actuator drive circuit and a power output path to the onboard actuator, and a relay drive circuit that drives the onboard relay. The onboard relay control device further includes a temperature detection unit that detects the temperature of the package, and a relay dew formation prevention unit that, when driving of the onboard actuator by the actuator drive circuit is ceased, continues driving of the onboard relay by the relay drive circuit so that a dropping speed of the temperature of the onboard relay becomes equal to or lower than a dropping speed of the package temperature detected by the temperature detection unit. |
