Design Of Comprehensive Test System For EGR Valve

The EGR valve is a very important part of the automobile exhaust gas recirculation device.According to the operation situation of the automobile engine and the change of the external environment,the automobile exhaust is automatically controlled to participate in the recycling of the vehicle,so as to control the effect of the emission of NOx to protect the environment.The technical level of EGR valve performance testing system is generally low in China.There are many shortcomings such as unreasonable test method and low testing precision,which lead to the quality of EGR valve in production can not be guaranteed.This paper designs a comprehensive performance test system for EGR valves to meet market demand.First,the paper introduces the working principle,development status and technical index of EGR valve in the background of the rapid development of automobile industry and energy saving and emission reduction.Finally,it points out the necessity of developing the EGR valve comprehensive performance testing system.Secondly,the design input demand of the EGR valve comprehensive performance testing system is expounded.Combined with the technical requirements of the enterprise,the overall scheme of the comprehensive performance testing system for 3 kinds of tested EGR valves is designed,and the other units of the system are introduced in detail.The hardware design includes the main control unit,the gas circuit unit,the adjustment unit and the position.The sensor characteristic detection unit and driving unit are set up.The software design includes PLC software and human-machine interaction touchscreen software.Finally,in view of the difficulty of controlling the pressure of the flow characteristic of EGR valve,a fuzzy PID control algorithm is proposed to automatically adjust the inlet pressure of the valve,and the experimental verification is carried out.Through the experimental data,the fuzzy PID control algorithm can be used to control the pressure of the valve effectively and meet the requirements of the design of the equipment;the reliability of the system is verified by the machine capability index and the number of experiments is used.It is shown that the system meets the industry standards.