Research And Development Of Insulation Detecting Equipment For Electric Vehicle

With the increasingly worse energy crisis and higher demand for environment protection, electric vehicles featuring in energy saving and environment protection draw much attention all over the world. Our country also made electric vehicle development strategy according to its actual situation, and was included in National 863 Program; R & D of relevant key technology has been carried out comprehensively, research on electrical and insulation safety is one of this. In this thesis, a set of electric vehicle insulation detecting equipment was developed for online monitoring high-voltage insulation performance of electric vehicles. The equipment can monitor insulation condition of whole high-voltage system, and give an alarm on insulation failures and other dangerous situation, thus ensure safety of vehicle and people.Analysis on high-voltage electrical system of electric vehicles was conducted firstly in this thesis, and established a circuit model, then proposed a new method to realize insulation resistance detection via insulation voltage detecting, and finished general scheme design based on this. FreeScale 16 bit microchip MC9S12DJ64 was adopted as main controller, then finished hardware design, device and component choosing and drawing of PCB, software programming was conducted in C language under Codewarrier development environment subsequently.Commissioning of electric vehicle insulation detecting equipment was finished in laboratory, and installed on Beijing electric bus No. 121, relevant experiment data all meet with requirement stipulated in contract.Improvements needed to be done was also proposed in this thesis, meanwhile, development thought was also given.