A pressure control valve system includes a pressure control valve, an electric actuator, an upstream pressure sensor, a downstream pressure sensor, and a controller. The electric actuator adjustably opens and closes the pressure control valve. The upstream pressure sensor measures pressure upstream of the pressure control valve and outputs a plurality of sequential upstream pressure signals over a plurality of successive periods in time. The downstream pressure sensor measures pressure downstream of the pressure control valve and outputs a plurality of sequential downstream pressure signals over the plurality of successive periods in time. The a controller receives the upstream and downstream pressure signals and outputs a plurality of sequential command signals to the electric actuator. Each sequential command signal is based on a respective one of the plurality of sequential downstream and upstream pressure signals for a respective one of the plurality of successive periods in time.

A fuel injection device that injects a liquefied gas fuel from an injection port to a combustion chamber of the internal combustion engine includes a passage forming member configured to define a fuel passage through which the liquefied gas fuel flows to the injection port, a temperature regulating unit configured to adjust a temperature of the liquefied gas fuel flowing through the fuel passage according to an operation state of the internal combustion engine, and a pressure regulating unit configured to adjust a pressure of the liquefied gas fuel flowing through the fuel passage according to the operation state of the internal combustion engine.

Provided is a high pressure fuel pump that smoothly achieves fuel supply while running and quickly relieves vapor generated during a restart by a piston operation of a high pressure fuel pump to improve a startup delay phenomenon, and an LPDI system including the same.

Embodiments of a gaseous or dual fuel electronic pressure regulation system (EPRS) for a multipoint fuel injection engine are described herein. Additionally, embodiments of a method for controlling the EPRS are provided. In particular, the EPRS employs an electronic pressure regulator (EPR) capable of accurately determining and controlling the mass flow of gaseous fuel into a fuel rail so as to avoid pressure droop and over- and under-pressurization of the gas admission valves (GAVs). By using the EPRS described above, mass flow is able to be distributed to the downstream manifold or engine cylinders very accurately, and the GAVs are able to be driven simultaneously in a pressure/pulse duration that is optimal for accurate and repeatable operation.

The present invention relates to a method for supplying fuel for a motor of a vehicle by a fuel supply system comprising: a first tank for containing a first fuel; supply means for supplying fuel to the motor; a supply line, for allowing said first fuel to pass from said first tank to said supply means; a return line, for allowing fuel to pass from said supply means to said first tank; a recirculating line, connected with said supply line and said return line, for allowing fuel to pass from said return line to said supply line; and valve means, configured to selectively direct fuel from said return line to said supply line by said recirculating line, or to said first tank; wherein said method comprises the steps of controlling the speed vehicle; controlling the vehicle motor load; defining a first threshold value of the vehicle speed; defining a second threshold value for the vehicle motor load; letting said first fuel passing from said first tank to said supply means through said supply line, and from said supply means to said first tank through said return line, preventing passage of fuel along said recirculating line, when the vehicle speed is lower than said first threshold value and/or motor load is lower than said second threshold value; or making said first fuel passing from said first tank to said supply means through said supply line and then through a closed circuit comprising a part of said return line, said recirculating line and a portion of said supply line, permitting passage of said first fuel through said recirculating line, so that said first fuel arrives again within said supply means, when the vehicle speed is higher than said first threshold value and motor load is higher than said second threshold value, so as to prevent an excessive increase within said first tank caused by inlet within the first tank of the first fuel warm arriving from said supply means.

A large two-stroke turbocharged compression-ignited internal combustion crosshead engine with a plurality of cylinders has at least one pressure booster for each cylinder for boosting fuel pressure, two or more electronically controlled fuel valves for each cylinder with an inlet of the two or more electronically controlled fuel valves being connected to an outlet of the at least one pressure booster. An electronic control unit is connected to the at least one pressure booster and the two or more electronically controlled fuel valves. The electronic control unit is configured to determine a start time for a fuel injection event, activate the at least one pressure booster ahead of the determined start time and pen the two or more electronically controlled fuel valves at the determined start time.

A large two-stroke turbocharged compression-ignited internal combustion crosshead engine with a plurality of cylinders has at least one pressure booster for each cylinder for boosting fuel pressure, two or more electronically controlled fuel valves for each cylinder with an inlet of the two or more electronically controlled fuel valves being connected to an outlet of the at least one pressure booster. An electronic control unit is connected to the at least one pressure booster and the two or more electronically controlled fuel valves. The electronic control unit is configured to determine a start time for a fuel injection event, activate the at least one pressure booster ahead of the determined start time and pen the two or more electronically controlled fuel valves at the determined start time.

A liquefied gas fuel feeding system can include a liquefied gas container configured to store liquefied gas and gaseous gas in cryogenic circumstances, a first fuel passage opening into an ullage space of the gas, a second fuel passage opening into a bottom section of the gas and provided with a controllable pump, at least two fuel delivery passages each configured to convey gas to a single gas consumer of at least two gas consumers, and a valve assembly configured to connect alternatively the first fuel passage or the second fuel passage to each one of the at least two fuel delivery passages.

Methods and systems are provided for continuously estimating a direct injector tip temperature based on heat transfer to the injector from the cylinder due to combustion conditions, and heat transfer to the injector due to flow of cool fuel from the fuel rail. Variations in the injector tip temperature from a steady-state temperature are monitored when the direct injector is deactivated. Upon reactivation, a fuel pulse width commanded to the direct injector is updated to account for a temperature-induced change in fuel density, thereby reducing the occurrence of air-fuel ratio errors.

Methods and systems are provided for fueling an engine with liquefied petroleum gas (LPG). In one example, a method may comprise pumping (LPG) from a fuel tank to a direct injection rail and not to a port injection rail. The method may further comprise supplying LPG from the direct injection rail to a port injection rail without returning the LPG to the fuel tank.