Research On The Measure-control System Of The Fuel Injection Pump Test-bed On The Basis Of SCM Technology

Fuel injection pump,which is the control and supply unit of diesel engine's fuel injection system,can directly affect diesel engine from three sides:accelerate performance,fuel consuming and quality of exhaust gas.So,it is very important to improve every technical characteristic of diesel engine by way of test accurately all kinds of technical parameters of fuel injection pump.Combined with the newest technology of current intelligent test-bed,the fuel injection pump test-bed measure-control system is designed by using single-chip microcomputer to auto-control entirely.Some techniques of measuring and controlling test-bed's every parameter are introduced particularly in the dissertation.,which include rotate speed closed loop system control,oil pump pressure monitor and the quantity of oil pumped,etc.Firstly,the dissertation made a summary of the before test-bed technologies. Secondly,based on anatomizing the control system configuration all-around and giving some parameters of the system which would be tested and controlled,this paper had designed the fuel injection pump test-bed measure-control system.And the system is composed of two modules:one is control and data collection system designed by AT89C51 microcomputer and the other is the upper monitor and manager system. Lower computer receives upper computer's instruction through RS232 UART and administers control of asynchronous motor speed,counts of fuel injection and fuel pressure display.Upper computer is supervisor of all test-bed system,which can send given operation order.And at the same time,it can display,collect and memory experimentation data.The system has friendly Chinese monitor interface and can progress simple data supervise.Aimed at the function to be achieved and the request of technical index,the hardware circuit of fuel injection pump test-bed controlling instrument has been designed in this paper by using AT89C51,which includes power system,analog and digital signal acquisition and conditioning circuit,single-chip microcomputer extend circuit,parallel I/O extend circuit,timer/counter extend circuit,data storage extend circuit,serial communication circuit and relay output control circuit,etc.Then,based on designing the fuel injection pump test-bed measure-control system's hardware,we realized the upper computer program,the lower computer program and the serial communication program by the use of the programmer tools of Keil C51 and Visual C++ 6.0 on the Window XP operating system.Through the debugging on-line and analog test of every function,this system has a favorable operating environment and friendly interface.It is easy to operate,upgrade and maintenance.The system has achieved the design requirement basically.