Research Of Micro-Electric Vehicle

With the deteriorating of the global environment and the gradual shortage of the petroleum energy,non-polluting electric vehicles are getting more and more attentions around the world.Electric vehicles replace internal combustion engine vehicles is the development trend of the automobile industry. On the basis of referencing the electric vehicles that has been put into the market,and having a model as the experimental subject,this paper has designed electric vehicle's section and the overall structures and the electronic control system.And proved the working reliability through the test and debug.In the machinery,this paper has designed the overall structure and powertrain, steering system, brake system, driving system and other systems based on the rear axle and rear motor(R-R)of the motor-drive axle combination. And calculated some important parameters of the system,and matched them. In the end this paper proved the rationality of all the systems.In control systems, MC9S12DG128 as the core controller and designed the hardware and software. In the hardware circuit,expanded the circuit with the MCU as the core. Designed the motor drive circuit and overcurrent protection, undervoltage protection, thermal protection and other protection circuits. In the software program, fuzzy control as a control algorithm, established the rule base to control the motor drive. And divided the entire program into PWM, ADC, timers, interrupts and other modules, sub-module designing and debugging.After the designing of the electric vehicle's body structure and the controller's hardware and software, I tested and debugged the whole design. Hardware debugging is using the multimeter, soldering iron, screwdriver and power, electrical and other equipment and devices to check if the circuit can work as expected. Software debugging first is put the program in the CodeWarrior development environment for running and debugging, then program the microcontroller when there are no problem in running the program. And then connect objects to test. In the process of debugging software program, I continuously adjusted and improved the program in order to achieve optimum.After commissioning and testing, it can be ensured that the system hardware and software are able to work as expected.