Pitching Motion Suppression with Better Energy Efficiency Performance in Large EVs

Large EVs are required to obtain more regenerative energy to extend a driving range. However, a pitch motion which is a change in vehicle attitude during braking occurs. Therefore, this study aims to obtain more regenerative energy and suppress the pitching simultaneously. In this study, two types of pitching suppression methods are proposed; steady and transient state pitching controls. Moreover a reducion gear ratio optimization method for obtaining more regenerative energy is also proposed that is compatible with the pitching suppression method. As a result of simulation, pitch RMS acceleration is suppressed by 14 % in JE05 mode, and the reducion ratio optimization method curbs energy efficiency deterioration which is caused by the pitching suppression.