Patent attributes
A fuel pressure control device has a feedback control section for setting a feedback control amount (F/B control amount) in accordance with a deviation between target fuel pressure and actual fuel pressure and a feedforward control section for setting a feedforward control amount (F/F control amount) in accordance with a required fuel injection amount and engine rotation speed. When an engine operation state is an off-idling condition, F/F-F/B combination control for validating the F/F control amount and for setting a control amount of a high-pressure pump by adding the F/F control amount to the F/B control amount is performed. When the engine operation state changes from the off-idling condition to an idling condition, control is switched to F/B single control for invalidating the F/F control amount and for using only the F/B control amount.
