Research And Implementation Of Online Test System Of Boost Pressure Limiting Valve

The boost pressure limiting valve is one of the core components of the automobile engine exhaust turbocharging system.Its assembly reliability,control performance and response speed have important influence on the overall performance of the engine.With the continuous improvement of exhaust gas turbocharging technology,people pay more and more demanding on the performance of boost pressure limiting valves.In order to ensure the manufacturing level of the boost pressure limiting valve,a stable and reliable test system is needed to monitor its quality.At present,the more advanced boost pressure limiting valve test equipment in used at home mainly rely on importation from abroad,they are expensive and lack of adaptability with the domestic production line.Therefore,it is very important to develop a high matching test system,which not only improves the research level of the internal boost pressure limiting valve,but also has great significance for the relevant enterprises to design the high-performance boost pressure limiting valve.In this paper,through the analysis of the structure and functional characteristics(including the working characteristics,magnetic properties,electrical characteristics)of the boost pressure limiting valve,a set of online testing system of boost pressure limiting valve composed of comprehensive performance test system and image error prevention platform was designed.The comprehensive performance test system mainly completes the test of the performance of the boost pressure limiting valve,which is divided into software module and hardware module.The software module completes the control of the test process and the test data processing,which including the analysis and storage of the stabilized pressure characteristics and life characteristics test process.The hardware module mainly completes the real-time data acquisition of gas pressure,flow and temperature,which including signal acquisition circuit,switching valve drive circuit,gas regulator source modules.Image error prevention platform completes the missing detection of the blade components which have impacts on the stabilized pressure characteristics,including the software module,hardware modules and control modules.The software module adopts the method of contour template matching to detect the blade,including image preprocessing,feature extraction,feature analysis,result output step.Hardware module completes the image acquisition of blade,including the industrial camera,lens,light source.The control execution module is used as the image acquisition assistant system to deal with the positioning function of the product.Firstly,the parameters such as air gap distance,minimum suction distance and spring force value which have effect on the performance of boost pressure limiting valve are analyzed by testing the different boost pressure limiting valves based on the overall debugging of the hardware module and software module of the online testing system.Secondly,it is proved that the system has good repeatability and accuracy by the analysis of the experimental data and error of the comprehensive performance test system.Finally,the main factors influencing the image quality of the system are analyzed by the test data from the aspects of light source illumination angle and ambient brightness,and the feasibility and reliability of the image error prevention are verified.