1. 研究目的与意义（文献综述）

1.purpose and significance (including domestic and foreign research status analysis)

in the current global energy crisis and the increasingly harsh atmospheric pollution, the search for alternatives for traditional internal combustion engines has begun. various countries and institutions are conducting continuous research and development work on this. almost all vehicle manufacturers, including well-known automobile companies at home and abroad, are looking forward to work hard in develope new energy vehicles that meet the market demand. as a result, the development of the drive system o new energy vehicles has been put on the historical stage. the drive system is the core part of an electric vehicle which determines the mechanism of the electric vehicle. the drive system of an electric vehicle is arranged in a manner that depends on the motor drive system.

in this design, a centralized electric drive system is adopted for new energy vehicles. the centralized drive is similar to the traditional car drive structure, replacing the internal combustion engine with electric motors and related components, and transmitting the motor output torque to the left and right wheels to drive the car through mechanical transmissions such as transmissions and reducers, son the basis of the traditional car structure. with a little modification, the operation technology is mature, safe and reliable. however, heavy volume and relatively low efficiency are some of the demerits of the system.

2. 研究的基本内容与方案

2.the basic content, objectives and technical solutions or measures of the design

2.1 basic content
(1) analyze the structural type of the centralized electric drive system and its components.
(2) determining the structural design of the centralized electric drive system and its components
(3) design calculation analysis of centralized electric drive system and its components
design and check the parameters of motors, transmissions, differentials, and half shafts using books related to automotive design and mechanical design.
(4) drawing the assembly diagram and main parts drawing of the centralized electric drive system
draw the parts of the transmission, the differential half shaft and the assembly drawing of the drive system.
(5) kinematics analysis of centralized electric drive system.

2.2 design requirements
for the design of the drive system, high instantaneous power, high power density, strong overload capability, high efficiency, wide operating speed range, high overall efficiency at high speed and low speed, and constant torque characteristics of the motor are required. bottom speed zone. the area has constant power characteristics; the structure is simple and firm, impact resistant, bumpy, reliable, maintenance free, low bottom cost, etc.
the main tasks completed during the design process:
(1) the design drawing must include the assembly drawing and the part drawing. the total drawing quantity is equivalent to not less than 2.5 pieces of 0# drawing, wherein the machine drawing paper quantity is equivalent to not less than 1.5 pieces of 0# drawing, and the machine drawing is in 3d drawing (need to be transferred) for the two-dimensional map) the paper shall not be less than one sheet of 0# drawings, and the contents of all drawings shall not be repeated;
(2) the graduation design specification is not less than 10,000 words;
(3) there are no less than 15 articles in the graduation design literature, including 5 foreign languages, and the literature search is not less than 200 words each;
(4) the opening report is not less than 1400 words;
(5) translating foreign language materials related to the profession is not less than 20,000 printed characters, and translated into chinese no less than 5000 words;
(6) completing a certain amount of programming tasks, the results of the active program and debugging calculations (arranged by the instructor).
(7) the graduation design specification checks that the full-text reproduction ratio is not higher than 30%, and the single chapter is not higher than 35%.

3. 研究计划与安排

3． Design schedule

4. 参考文献（12篇以上）

[1]黄帅,杜明星,丁一夫.电动汽车电驱动系统传导电磁骚扰特性研究[j].电力电子技术,2017,51(5):93-96.

[2]张戟,王洪武,蔡浩雄.电动汽车驱动系统 emc 仿真研究[j].汽 车 工 程,2014,5:580-585.

[3]李曼,陈敬渊,孙悦超,等.纯电动汽车传动系统传动比的优化[d].广东 湛江:岭南师范学院，机电研究所,2015.