Abstract: An electromagnetic valve driving device includes: a maximum detection unit configured to detect a maximum point when time-series data of a differential value of a counter electromotive voltage generated in a solenoid has changed from an increase to a decrease by retrospectively tracing the time-series data in an opposite direction of a time series; and a valve closing time detection unit configured to execute a determination process of retrospectively tracing the time-series data from the maximum point detected by the maximum detection unit in the opposite direction and scanning whether or not an amount of decrease in the differential value from the maximum point exceeds a predetermined threshold value and detect a maximum time, which is a time of the maximum point, as a valve closing time of a fuel injection valve when there is an event in which the amount of decrease exceeds the predetermined threshold value.

Abstract: An electromagnetic valve driving device includes: a maximum detection unit configured to detect a maximum point when time-series data of a differential value of a counter electromotive voltage generated in a solenoid has changed from an increase to a decrease by retrospectively tracing the time-series data in an opposite direction of a time series; and a valve closing time detection unit configured to execute a determination process of retrospectively tracing the time-series data from the maximum point detected by the maximum detection unit in the opposite direction and scanning whether or not an amount of decrease in the differential value from the maximum point exceeds a predetermined threshold value and detect a maximum time, which is a time of the maximum point, as a valve closing time of a fuel injection valve when there is an event in which the amount of decrease exceeds the predetermined threshold value.