Research Of Braking System Of Electric Vehicle

With the problem of energy grows more and more acute, the electric vehicle is attached by a lot of people. In the same time, the safety of EV is further improved. As the EV uses the batteries as its power, it can not be charged everywhere. So, how to make it run as far as it can in the condition of insure the safety becomes a new problem.Be different from the fuel-engined vehicle, the vacuum pump of the vacuum booster braking system in EV is not always running with the motor. Only in the condition that the pressure of air container can not meet demand the vacuum pump will run. So that it can save as much energy as it can to make the EV run furthest.In the same time, when we are braking a car, a lot of energy is consumed in this process. According to incompletely statistics, the percent of energy in this process count for 20% to 30%. So, if we can transmit part of this energy back to the batteries, it will help the EV improve the maximal mileage much more.According to the two function mentioned before, this paper introduces a suit of vacuum booster braking system that can be used in EV. It includes two parts, one is vacuum booster braking system, the other one is energy feedback system. We can calculate a vacuum degree with modeling the speed of vehicle and the strength of driver steps on the pedal. This vacuum degree can be used as threshold of controlling the vacuum pump. Based on these works, we can calculate the percent of energy feedback with modeling the speed of vehicle and the resistance and driving force. At last, we can establish a whole system project, and it can be transplanted according to different type, so as it can be widely used.At last, we can a software called SYSTEM-DESK, which is widely used in vehicle designing industry, to simulate the whole braking system. By using the function of partition, we can divide the system into several modules to make the compiling work easier. Then use the tool of tresos studio to complete the parameter editing work. When we are facing with different types of cars, we can just modify the corresponding parameter to meet the needs, we do not have to rebuild all the system again, this will save time and work greatly for the designers.