String stable control of electric heavy vehicle platoon with varying battery pack locations

Integration of heavy commercial road vehicle platooning concept and electric vehicle technology is a promising approach as far as sustainable freight transportation is considered. This article attempts to design a string stable controller for an electric heavy commercial road vehicle platoon by incorporating critical factors such as complete vehicle dynamics model, pneumatic brake system model and cooperative braking between friction and regenerative braking systems. The sliding mode control technique has been used for string stable platoon operation. The impact of various battery pack locations on string stability has also been analysed. The performance of the controller has been investigated by considering electric heavy commercial road vehicle platoon operation on different road slope (straight, uphill and downhill) conditions, dry and wet road conditions and vehicle load conditions. It has been observed that the battery pack location has a significant influence on string stability with respect to the platoon operating conditions. During operation on straight and level roads, string stability was achieved irrespective of the location of the battery pack. However, during downhill and uphill driving conditions, it was found that placing the battery pack near front and rear axle locations, respectively, helped in ensuring string stable platoon operation.