FUEL PRESSURE CONTROL APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide a fuel pressure control apparatus capable of suppressing unnecessary variation of a fuel supply pressure when switching a fuel supply state of a fuel to be supplied to a fuel injection part.SOLUTION: The fuel pressure control apparatus includes: an electrically driven fuel pump for changing discharge capacity in accordance with a driving voltage; a pressure reduction valve capable of switching a valve state to a valve opening state capable of displaying a pressure reduction function for reducing a supply fuel pressure Pr of a fuel to be supplied to the fuel injection part or to a valve closing state for stopping the pressure reduction function; and a control mechanism for variably setting a target pressure of the supply fuel in accordance with an operation state of an internal combustion engine and executing variable control of the fuel pump driving voltage Vp and switching control of the opening/closing state of the pressure reduction valve in accordance with the target pressure. The control mechanism, when switching the opening/closing state of the pressure reduction valve, changes the fuel pump driving voltage Vp so that an increase/reduction direction of the supply fuel pressure due to a change in the discharge capacity of the fuel pump is reversed against an increasing/reducing direction of the supply fuel pressure Pr due to the switching, and then inputs a switching control signal for requesting switching to the pressure reduction valve.