CONTROL METHOD OF BI-FUEL FEED SYSTEM

摘要

The present invention relates to a control method of a bi-fuel feed system. The control method includes the steps of inspecting a set state of a mode switch when an engine starts; proceeding to a gasoline driving mode or a liquid petroleum gas (LPG) driving mode based on the inspected result; directly injecting a gasoline fuel into a combustion chamber of the engine by driving the gasoline driving unit in the gasoline driving mode to drive the engine; and injecting the LPG fuel into the air sucked via an intake manifold by driving an LPG supply unit in the LPG driving mode to drive the engine using the mixed gas. Therefore, in case where the fuel injection types are different from each other, such as the direct injection type gasoline fuel supply system and the LPG fuel supply system, it is possible to exactly supply the gas fuel into the engine of the vehicle by calculating injection point and injection time of the LPG fuel based on the injector driving signal of the gasoline fuel supply system. [Reference numerals] (11) Gasoline tank; (21) Fuel pump; (31) Electronic control unit; (32) Gas fuel electronic control unit; (33) Fuel control driver; (AA) Fuel rail pressure signal; (BB) Cut solenoid valve control signal; (CC) LPG pressure & temperature detection signal; (DD) Second injector control signal; (EE,GG) Injector driving signal; (FF) High-pressure valve contol signal; (HH) Ignition plug driving