electrical hydraulic power steering (EHPS). Add electronic control and executive components to the hydraulic power steering system (see power steering system), and introduce the speed into the system, so that the size of the help varies with the speed. Electronic-controlled hydraulic power steering system mainly through the speed sensor to pass the speed to the electronic components, or ECU, control the electro-hydraulic conversion device to change the power steering characteristics, the power will be reduced with the increase of speed, thus increasing the road sense of high-speed driving, better taking into account the lightweight of low-speed steering and the road sense of high-speed steering.