Method and System for Testing the Working Characteristics of Vehicle Fuel Injector

Background: The vehicle fuel injector directly affects the power performance, emission characteristics and economic efficiency of the engine. At present, several testing standards are stipulated on accurate measurement of the working characteristics of fuel injectors. Objective: The purpose of this study is to provide an efficient patent about the method and system for testing the working characteristics of a vehicle fuel injector. Methods: Two key techniques are significant to establish a standard test environment. The patent about the pressure control approach and the injector driving method was proposed. The adaptive fuzzy PID approach was applied to control pressure. An adaptive multi-functional driver was designed and developed for both the voltage-driven and current-driven port fuel injectors. Results: The experiments on the two key technologies were conducted. During the dynamic flow test, the settling time using the system was 1ms. For the static flow test, the settling time was 1 s. The maximum changing rate of pressure fluctuation was 1%. Then, the system was verified by test on the flow characteristics and dynamic response of the voltage-driven and current-driven injectors. The linear deviation of each dynamic flow curve was between ± 3% to ± 6%. Furthermore, the deviation of the dynamic flow curves from the repeated test was small. The maximum deviation of the static flow results was less than 4% and the dynamic response of the injector varied with the change of the pressure. Conclusion: The system meets the requirements of the related standards. The experimental results prove that the system is stable and reliable.