ENGINE CONTROL UNIT

摘要

An engine control unit (ECU) in which each of the following engine operating parameters are detected: engine speed (60), throttle position (62), manifold absolute pressure (MAP) (64), gas pressure (66), gas temperature (68), battery voltage (70), air temperature (72), engine phase (74) and boost pressure control valve (BPCV) feedback position (76). Each of these parameters is provided as an input in the form of an electrical signal to the ECU controller, for controlling the operation of a gas fuelled internal combustion engine. The ECU controller typically employs the detected engine speed (60) and throttle position (62) to calculate a percentage full load (PFL) value for the engine. PFL is a non-dimensional measure of the load or torque produced by or required from the engine. The calculated PFL value (78) can then be employed by the ECU controller to calculate the injector ON time (IOT) (80) for each gas injector in a gas delivery system for the engine. Typically, the PFL (78) value is employed together with the engine speed (60) to calculate a required manifold absolute pressure (MAP) value (82). The calculated value of required MAP (82) may then be employed, together with the PFL value (78), to calculate a percent allowable load (PAL) value (84). The PAL value (84) is then employed by the ECU controller to calculate the IOT (80) and spark advance (88) for the engine. By employing gas injectors and accurately calculating the IOT, the ECU can control the correct amount of gaseous fuel to be injected into each cylinder to achieve optimum engine performance under the full range of engine speed and load conditions.