Analysis of Energy Consumption for Various Power Assisted Steering Systems

The energy consumption of conventional open-centre hydraulic power steering was mapped to pinpoint areas of potential for improvement. Using this data, equivalent maps were generated for existing, and potential, competing systems. These maps were used to identify likely future trends in this area.

The results immediately illustrate the gross inefficiency of the conventional system due to high parasitic losses and indicate not only that systems that operate purely “on-demand”, such as electric power steering (EPS), are likely to be the optimum solution at least as far as energy consumption is concerned but also that interim solutions such as electro-hydraulic power steering (EHPS) can make significant contributions.