Design and implementation of algorithms for one pedal driving in electric buses

Nowadays, interest in Electric Vehicles (EVs) is increasing day by day. Range problem of EVs decrease rapidly due to developing battery technologies however, the biggest problem of electric vehicles is still seen as range anxiety. The One Pedal Driving (OPD) which only accelerator pedal is enough to drive and stop the vehicle can overcome this anxiety problem and incease the ease of electric vehicle penetration. Regenerative braking has become standart for almost all electric vehicles but, the implementation of the system has always been a little different between manufacturers. In this study, OPD mode is developed for electric buses which has 100kW and higher electric motor and also it can be applied to other electric vehicles with minor changes on the algorithms. OPD would make it possible to use just the accelerator pedal to both speed up and slow down the vehicle. While electric vehicle is driving, the power is sended from vehicle's battery pack to wheels via electric motor. An inverter which turns battery's electrical power into correct form of power needed to generate desired traction torque is used. Basically, electrical energy is converted into kinetic energy. On the other hand, regenerative braking works by switching that process the other way around, turning the motor into generator to convert the wheel's kinetic energy back into electrical energy that can be stored in the battery. This process also slows the vehicle down since energy converted from kinetic energy to electrical energy. Adding such a new driving mode to electric vehicles can extend its range considerably. One of the most important purpose of this study is obtaining the accelerator pedal position correctly and accordingly implementing the required amount of positive/negative torque by the help of new algorithms. Another aim of this study is to correctly manage the vehicle traction torque without compromising the comfort of the passengers in the vehicle. Tests were conducted in accordance with the objectives of this study and the opinions of the drivers were obtained. As a result of tests, it has been observed that OPD mode provides more efficient, safer and much more comfortable driving compared to standard driving modes.