Development of alternative steering models for ev bus: a preliminary study on the conversion of hydraulic to electric power steering

• Main Authors: Nazaruddin Nazaruddin, Danardono A Sumarsono, Mohammad Adhitya, Ghany Heryana, Rolan Siregar, Sonki Prasetya, Fuad Zainuri
• Format: Article
• Language: English
• Published: PC Technology Center 2021-06-01
• Series: Eastern-European Journal of Enterprise Technologies
• Subjects: assist motor; wheel drive; steering column; pinion; rack; vehicle speed; torsion motor; truss structure; frame structure; four-bar linkage
• Online Access: http://journals.uran.ua/eejet/article/view/227329

This study aims to develop alternative steering models for the EV bus. The EV bus uses its energy source from the main 384 VDC 300 Ah battery and the secondary battery with a capacity of 25.8 VDC 100 Ah. The use of energy in this electric bus is divided into the main components, namely the BLDC motor as the main drive of 200 kW, 15 kW of air conditioning, 7.5 kW of hydraulic power steering, a compressor for the air braking system of 4 kW, and accessory components. The other is 2.4 kW. It is expected that this 7.5 kW electric power can be reduced by an electric system by up to 20 %. This research will study the steering system with an electric power system (EPS) to convert the hydraulic steering system (HPS). With this EPS system, it is hoped that controlling the vehicle’s motion towards the steer by wire will be easier. Initially, data were collected from the types of large vehicles from various well-known brands about the steering system used. A large commercial vehicle that purely uses EPS is not yet found. The model developed for EPS on this electric bus is through the reverse engineering method by redrawing all the components involved in the previous steering system. Because this type of EV bus is included in the upper mid-size class, this paper proposes two new EPS models, namely the addition of an assist motor on the drag link and on the steering rack. The links involved in this system are wheel drive, steering column, lower steering column, rack and pinion gear, assist motor, drop link, drag link, drop link extension, drag link extension, tie rod, knuckle, kingpin, tire, axle beam and several others. The values of stiffness, inertia, and damping of each link will affect the driver’s torque and the assist motor as a wheel speed function on this electric bus. The steering structure of the EV bus consists of a truss structure and a frame structure with a kinematic structure consisting of two four-bar linkages joined together