Inrush Current Load Regulation for Small Mobility Application

Small mobility vehicles such as electric scooters are becoming an integral part of the transition towards electrified transportation. The motor’s starting inrush current in loaded conditions leads to the malfunction of different power electronic switches. It exceeds the absolute maximum current ratings of the components and traces on the PCB, which causes a system or e-scooter controller failure. Moreover, the extraction of such high currents also has undesirable effects on the battery pack. This paper proposes an inrush current suppression design methodology in loaded conditions for the e-scooter motor drive controller. A new and improved sliding mode reaching law is proposed to improve the performance of the normal sliding mode controller. The speed of the system state reaching the sliding mode surface is enhanced. The performance of the proposed methodology is compared with a state-of-the-art bench-marked e-scooter from the market. The proposed control topology is verified through short and long-term hardware testing for inrush current, aided by thermal, power, and current flow analysis.