Reaserch on an Electronic Control System of CNG/Diesel Dual Fuel Engine

In order to convert the high pressure common rail system engine to CNG/Diesel dual fuel engine, an electronically controlled system is developed. The system includes a CNG fuel supply system, the CNG electronic control unit (ECU) and its matching harness etc. During starting and idle load conditions, the engine runs under pure diesel mode, when the speed and load reached a certain set point, the diesel ECU reduces the pilot diesel quantity, meanwhile, the CNG ECU increases the natural gas quantity, then the engine runs under dual fuel mode. The engine experiment data show that in different conditions, the highest substitution rate is 90% and the average substitution rate is 83%; the average savings ratio of operation cost per hour is 26%.