Control System Design of Electrial Fuel Pump

　　Control System Design of Electrial Fuel Pump
　　From 1970s, small military aviation and aviation platforms under several hundreds gram are first developed in the developed countries. So far, several decades elapse. Turbojet engines have some advantages, such as, accelerating fast, designing simply, which is most suitable for the earliest practical use of the jet engine types. In the development trend of modern military aircraft and missile is going to be unmanned, small and micro, micro - turbojet engine is being taken more and more importance.Turbojet engine control system has traditionally been Alnico Magnets realized by the mechanical and hydraulic-mechanical pneumatic regulator, its fuel control system is achieved by a mechanical device attached to the engine. However, according to the structural and applying characteristics of the small or micro-turbojet engine, its oil supply scheme can not be realized by the traditional annex pumps of the engine.According to the control request of some type miniature turbojet engine, its oil supply control system was designed in this paper.
　　We first analyzed the oil supply control methods of turbojet engine and the present development situation and tendency of the electrical fuel pump using in the miniature engine oil supply system. Referring overseas similar engine oil supply control methods, we designed electrically operated oil supply system by using brush permanent magnet direct-current servo motor meshing the gear pump.Analyzing the electrical fuel pump working mechanism, we chose bipolar H bridge type PWM converter as the driving scheme of the DC servo motor in the electrical fuel pump, and used the entire closed-loop control system, which was formed by the voltage negative feedback electric current compensate control system replacing the traditional speed negative feedback, as the control scheme of the motor. Then we established the voltage negative feedback electric current compensate control system mathematical model based on the mathematical models of the DC servo motor, the bipolar H bridge http://www.999magnet.com/products/108-alnico-magnets PWM converter and the voltage negative feedback electric current compensate control element, and designed the controller of electrical fuel pump control system by using the PID control method, and simulating the control system in the Simulink environment of MATLAB software.Based on the designed system, bipolar H bridge type PWM (pulse width modulation) motor-driven control hardware system was designed, which was used 83C552 MCU produced by PHILIPS Corporation as its master control chip. Meanwhile the principle and circuit designs of each constituent of the system (such as controller, driving circuit, and feedback circuit) were introduced in the paper in detail.Finally we made the principle test on the sample circuit board, the result showed that the control system of the electrical fuel pump oil supply system, which was designed by us, could meet the oil feed needs of the engine.