Dual valve controlled energy recovery EHA

Electric Hydrostatic Actuator (EHA) is a highly integrated hydraulic system that is widely used in multi-electric and all-electric aircraft due to its high power density. One of the main constraints which limit increasing of EHA power density is the high heat output of the motor. This not only leads to an increase in the volume of the motor, but also increases the chance of thermal failure of the motor. In order to deal with the heat of the EHA motor, the international mainstream method is to increase the motor speed, reduce the motor current, thereby reducing the motor heating, but do not pay attention to the EHA motor running under the conditions of heat can be avoided. This article proposes an energy recovery EHA named ER-EHA, which can recover the hydraulic energy when EHA works in positive load conditions and release it when the load is reversed. This structure reduces the motor heating and improves the efficiency without affecting the dynamic characteristics of the EHA system. The improvement of the odds ratio have great application prospects in increasing the power density of EHA.