Research On Rapid Virtual Test System For Vehicle Circuit Protection Under Multi-load Conditions

The significant increase in vehicle electrical loads is due to the constant improvement of people’s demands for vehicle safety and comfort.So it is necessary to systematically test the safety of vehicle circuits during the vehicle design phase.In particular,it is difficult to test the rationality of harness matching.With the support of an industryuniversity-research cooperation project,the test methods of vehicle circuit protection was studied in the paper.Meanwhile the rapid virtual test system was custom-developed for the vehicle circuit protection under multi-load conditions The research is of high theoretical and engineering application value.Main works of the paper are as follows.(1)The testing principle of vehicle circuit protection was systematically described.Then the functional requirements of the rapid virtual test system were determined for vehicle circuit protection under multi-load conditions.Finally,the overall structure of the test system was built.(2)The hardware of the test system was designed based on the c RIO,which included four parts,i.e.the sensor,the data collector,the PC and the external power supply,etc.The non-contact current clamps and the insulation penetrating clip sets were used to measure large current and high voltage without breaking the wire.The K-type thermocouples were used to measure surface temperature of the wire and the fuse box.The hardware selection ensured the test security and on-site operation convenience.(3)The software of the test system was custom-developed based on the Lab VIEW,which included the FPGA program and the RT program running in the data collector,and the upper computer program running on the PC.The software adopted these technologies such as the multi-threaded modularization and the state machines to ensure that the software ran stably and reliably and consumed less resource.The upper compute software could display data,record data,and generate test reports using a key trigger,and so on.Besides,the functions integrated in the software,such as the intercepting data,the scaling curves,and the automatically extracting peaks,and so on,effectively improved on-site testing efficiency.(4)The data acquisition accuracy and consistency verification tests of the test system,as were as the vehicle circuit protection teses have been performed.The results showed that the functions of the test system met the design requirements,and the actual vehicle test efficiency and working reliability were significantly improved.The test system in this paper was custom-developed according to test requirements,which had high integration,good scalability,high test efficiency,and easy maintenance,etc.The test system has been used for nearly one year for the vehicle test and has good performance.The function and reliability of the test system have been fully verified.