• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.13 no.3
• /
• pp.1008-1013
• /
• 2012

Electro-hydraulic power steering (EHPS) system is the power-assisted steering which operates the hydraulic pump by BLDC motors for assisting the steering force. EHPS consists of BLDC motor, gear pump, oil-hydraulic circuit and steering system. Since EHPS is a convergence system consisting of electricity and electronic, hydraulic and mechanical system, it is difficult to establish the simulation model. In this paper, the mathematical model of EHPS system components were presented, and the simulations of the multi-domain system were performed by using AMESim. The trial and error of development would be reduced by using this simulation results, and it would be helpful for developing high-quality EHPS.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.25 no.1
• /
• pp.103-110
• /
• 2017

Most commercial vehicles have adopted the hydraulic power steering system. To reduce fuel consumption and to improve steering controllability, a hybrid electric power steering system is being developed for commercial vehicles. In this study, the HILS (Hardware In the Loop Simulation) system equipped with a commercial vehicle hybrid electric power steering system was developed and the vehicle dynamic performance of a truck with the steering system was evaluated. The hybrid electric power steering system is composed of the EHPS motor pump, column mounted EPS system, and ball nut steering gear box for heavy commercial vehicles. The accuracy of vehicle models equipped with the HILS system was verified with comparisons between the simulation results and field test results. The road reaction forces of the steering system were generated from the vehicle model and verified using field test results. Step steering tests using the verified HILS system were carried out and the performance of a newly developed commercial vehicle hybrid electric power steering system was evaluated.

• Proceedings of the KIEE Conference
• /
• 2007.04c
• /
• pp.119-121
• /
• 2007

The increment of electric power demand causes interest on new higher power system such as 42V Power Net, and furthermore necessity for development of energy storage device is highlighted recently. Owing to high efficiency and easy speed control of brushless DC(BLDC) motor, the demand of BLDC motor that has high power and low noises are increasing. Especially demand of interior permanent magnet(IPM) type BLDC with high efficiency and high power in electric motion vehicle is increasing. This paper presents the design of the BLBC motor for EHPS(Electro-Hydraulic Power Steering) in 42V system and verified the characteristics by simulation and test results.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.24 no.4
• /
• pp.401-407
• /
• 2016

For high fuel economy, many kinds of unit in vehicle have been developed. In steering system, as a result, HPS(Hydraulic Power Steering) system has been replaced as EHPS and EPS system. But the structures of these systems are totally different, and that causes the uncertainty of fuel economy evaluation. Therefore we undertake to research to find results and tendency of fuel economy and energy in steering system. For accurate evaluation, we modeled different types of steering systems on same vehicle model. The simulation came into action on various driving cycle. The driving condition is designed to show standby power of pump. Results show differences of fuel efficiency and energy consumption.