Wheel slip regulation of electrified heavy road vehicles using regenerative braking

This paper proposes a control scheme to use regenerative braking for Wheel Slip Regulation (WSR) in Heavy Commercial Road Vehicles (HCRVs). Typically, in HCRVs, WSR is achieved using pneumatic friction brakes. However, in electrified vehicles regenerative braking is available and this can be beneficial as electrical machines have higher bandwidth compared to a pneumatic brake system. In this study, a sliding mode control based active co-operative braking strategy is proposed for WSR in an electrified HCRV. The proposed control strategy was programmed in MATLAB/Simulink® and implemented in a Hardware-in-loop brake system. The experimental results showed that the proposed active co-operative braking strategy reduced the Mean Absolute Percentage Error in tracking slip ratio in the range of 6.7 % to 1.1 % compared to conventional friction braking for different operating conditions. This reduced the stopping distance in the range of 3.5 % to 0.6 %. Thus, co-operative braking provided better slip tracking leading to reduced stopping distance.