Key Technologies Of Electric Control System For Diesel-LNG Dual Fuel Engine With Sequential Injection

Refitting a conventional non-road diesel engine to a diesel-LNG dual-fuel engine can not only effectively reduce the emission of pollutants,but also save fuel costs and improve the economy of the engine.The topic of this paper is derived from the University-Science and Technology Cooperation Project which is funded by Science and Technology department of Fujian Provincial.In this paper,the key technologies of the Diesel-LNG dual-fuel engine electronic control system are researched and developed.The developing process of electrical control system based on SL2110DKT Unit pump diesel engine includes the design and manufacture of the electronic control unit hardware,the design of the basic software of the electronic control unit and the calibration software of the host computer.Development.The electronic control unit hardware is designed and developed using Mentor Graphics PADS software,including the main control chip minimum system circuit,power supply module,sensor signal processing module,actuator driver module,CAN communication circuit and PCB board.The key work is to design the boost circuit and the electromagnetic valve drive circuit to match the selected solenoid valve.When designing the PCB board,the single point grounding method and the minimum loop law are used to reduce the electromagnetic interference.The basic software of the electronic control unit adopts CodeWarrior software to program,debug and generate object code,mainly including the main program of the single-chip microcomputer,the bottom driver,the upper driver,and the interrupt processing task,so that the electronic control unit can support multi-fuel engine sequential injection.At the same time,in combination with diesel engine calibration work,the CAN bus driver,CCP driver and CCP instruction parsing program are integrated in the basic software,and a dual memory data area is designed for the selected single-chip microcomputer.The MAP data can be online calibrated through the FLASH update function.Based on Visual Studio 2013 software for PC calibration software development,including the user interface design and the background logic function of each module.The calibration software functions are mainly divided into four modules:communication settings,system parameters,MAP calibration,and data monitoring.Complete the connection of the upper and lower position machines in the communication setting module;calibrate the independent parameters in the system parameter module;in the MAP calibration module,the A2L file and the S-Record file can be parsed,and the MAP data can be calibrated online/offline,And can carry on the visualization operation and the import/export to the MAP data;In the data monitoring module,may monitor and records the diesel engine measurement variable in real time.Finally,bench tests and hardware-in-the-loop tests were performed on the developed electronic control unit and calibration software to verify the effectiveness of the developed hardware and software systems.