Abstract As is known to all, the structure of the chassis has been greatly simplified as the application of in-wheel motor in electric vehicle (EV) and distributed control is allowed. The micro EV can alleviate traffic jams, reduce the demand for motor and battery capacity due to its small size and light weight and accordingly solve the problem that in-wheel motor is limited by inner space of the wheel hub. As a result, this type of micro EV is easier to be recognized by the market. In the micro EV above, two seats are side by side and the battery is placed in the middle of the chassis. Besides, in-wheel motors are mounted on the rear axle and only front axle retains traditional hydraulic braking system. Based on this driving/braking system, distribution of braking torque, system reliability and braking intensity is analyzed in this paper. In order to coordinate with traditional hydraulic ABS control to ensure the braking stability of the vehicle, model following control (MFC) is adopted to fully utilize the fast and accurate torque response of motor for slip prevention and control effect influenced by characteristics of motor is analyzed. In conclusion, only simple and minor changes have been made to the braking system of traditional vehicle which makes the micro EV cost less and easier to popularize. Introduction With the challenges of energy and environment crisis, EV is developing rapidly due to its advantages of high efficiency and zeros emission. However, driving range is limited and price is high when compared with traditional vehicles which are considered as an obstacle to development of EV . As a result, micro EV is born with the advantage of narrow and lightweight body which not only costs less, but also leads to less traffic jam. Nowadays, many automobile manufacturers and research institutes have carried out various research and development of micro EV . Figure 1 shows some micro EVs developed by automobile manufacturers at home and abroad. It can be easily seen that curb mass is lighter and max speed is lower of EVs promoted by domestic automobile manufacturers when compared with that developed by foreign automobile manufacturers. That’s to say, EV which has low speed and small size is more popular in China. Figure 1. Parameters of some micro EVs at home and abroad On the other hand, compared with traditional central driven EV , some mechanical transmission parts are abandoned in EV driven by the in-wheel motor. As a result, mechanical loss is largely reduced and the structure of vehicle chassis is simplified. Besides, the driving/ braking torque of every electric wheel can be controlled quickly , accurately and independently, which makes the dynamic control of vehicle more flexible and thus improving the performance of vehicle. In-wheel motor is accordingly regarded as the future driving scheme of vehicle [ 1, 2]. In this paper, a micro EV is developed with two seats side by side. When it comes to current technology of in-wheel motor, it can well meet the requirements of this micro EV . To make full advantage of its driving performance, in-wheel motors are adopted on the rear axle. Traditional hydraulic braking system is only mounted on the front axle which not only provides most of the braking torque, but also makes the structure of electric wheel simplified. In order to coordinate electric-hydraulic braking torque to ensure the braking performance of the vehicle, MFC is adopted to fully utilize the fast and accurate torque response of motor which not only improves anti-lock braking control effect of hybrid braking system, but also recycles part of the braking energy.Design and Research of Micro EV Driven by In-Wheel Motors on Rear Axle2016-01-1950 Published 09/18/2016 Guirong Zhuo, Subin Zhang, and Kun Xiong Tongji University CITATION: Zhuo, G., Zhang, S., and Xiong, K., "Design and Research of Micro EV Driven by In-Wheel Motors on Rear Axle," SAE Technical Paper 2016-01-1