Electronic Thermostat Multi-parameter Comprehensive Measurement System

With the rapid increase of car ownership year by year,the problems of energy consumption and environmental pollution caused by vehicle traffic are becoming more and more serious.How to reduce engine energy consumption has become a key research problem for major car manufacturers.The reliable operation of the electronic thermostat plays an important role in the safety of the vehicle thermal management system and the engine,It directly affects the energy efficiency of the engine.Therefore,after the electronic thermostat is produced and assembled,it is necessary to carry out multiparameter testing to ensure that it meets the design indicators.In this dissertation,a certain type of electronic thermostat is the research object.According to its demand analysis,determining external leakage,internal leakage and motor current as detection parameters.The leak detection method is studied,combined with the actual detection requirements,the external leak detection model based on the differential pressure method and the internal leak detection model based on the mass flow method are established,and the electronic thermostat multi-parameter measurement system was developed.The main research contents are as follows:(1)The overall structure design of the system.To determine the design requirements and key parameters of the system by analyzing the working principle and structural characteristics of the electronic thermostat.According to the parameters to be measured,the relevant measurement methods are studied and the overall structure of the system was designed.(2)Design of leakage detection system.In order to detect the air tightness and internal leakage of the electronic thermostat,a gas circuit detection system is designed,including external leakage and internal leakage detection modules.According to the process of detecting external leakage by differential pressure method and detecting internal leakage by mass flow method,the gas circuit and electric control platform were designed.(3)Design of current characteristic detection system.In order to realize the current parameter detection task of electronic thermostat,a motor current detection system with STM32F407ZGT6 as the core processor was developed.(4)Software design of multi-parameter measurement system.In order to realize the process control of the multi-parameter measurement system of the electronic thermostat,C# was used to write the application program of the upper computer to realize the functions of acquisition,storage,processing,judgment and display of the detection data.Finally,in order to verify the function of the electronic thermostat multi-parameter measurement system designed in the dissertation,the external leakage,internal leakage detection and motor current detection experiments were carried out on the final inspection platform of the electronic thermostat.The experimental results show that the system is reliable and can effectively measure the external leakage and internal leakage mass flow of the electronic thermostat.The measured current has a small deviation,and the system meets the detection requirements of actual products.