Patent attributes
A hydraulic system includes a pump to pressurize and output hydraulic fluid, an electric motor selectively driving the pump, and a controller to selectively control a target speed of the electric motor based on input from an operator control. A proportional directional control valve is in the load circuit and communicates with the pump and the controller. The proportional directional control valve controls a flow of hydraulic fluid to a hydraulic actuator associated with the load circuit such that the flow of hydraulic fluid to the hydraulic actuator is proportional to a signal provided by the controller. The signal is a function of the input from the operator control. Flow of hydraulic fluid to the hydraulic actuator through the proportional directional control valve is varied by the controller making a) variations of the target speed of the motor, and b) variations of the signal to the proportional directional control valve.