Development Of A Motorcycle EFI System

As the electronic fuel injection system can determine the fuel injection quantity according to the engine working conditions,so as to reduce the emission of pollutants.With the promulgation of the national four emission regulations,the motorcycle industry is facing severe challenges.The EFI technology will completely replace the traditional carburetor technology.The research object of this paper is two national four emission vehicles on the same platform.Because the conventional electronic fuel injection system can not meet the vehicle layout requirements,therefore,this paper needs to develop a new EFI system.Based on the analysis and comparison of the components of EFI system,this paper chooses the external oil pump as the breakthrough point,and proves that its fatigue life can meet the development requirements through the finite element analysis method.Through targeted measures and improvement,the two main problems of high noise and poor air resistance in the test process were solved.Finally,a new EFI system was successfully developed.The research work and innovation of are mainly include the following contents:Aiming at the noise problem of the external fuel pump,a load control method of the fuel pump is proposed.The fuel injection quantity required by the engine is calculated according to the engine speed and throttle opening signal.Then,according to the PWM control principle of motor speed regulation,the control pulse width of the pump motor is deduced according to the power supply voltage,and the control strategy is written into the ECU program,so that the fuel pump is always in the best condition.The test results show that the noise of the fuel pump can be reduced by load management.At the same time,in order to solve the poor air resistance in the fuel supply system,according to the basic theory of the formation of air resistance,the independent fuel pump and fuel nozzle are used in the structure,which effectively reduces the working temperature of the fuel pump and the oil pipe.Secondly,the layout of the fuel pump is optimized to further reduce the working temperature of the fuel pump,so as to reduce the poor air resistance The test results show that the A / F value and engine speed can remain stable even in the limit state.Finally,the related tests on the emission,durability,power and fuel economy of the EFI system are carried out,which further verifies the success of the development of the new EFI system.