Fully-electrically-driven hydraulic excavator power system

The invention relates to a fully-electrically-driven hydraulic excavator power system. The fully-electrically-driven hydraulic excavator power system comprises hydraulic execution components, two-way constant-displacement pumps, servo motors, a frequency converter, a controller and a clutch controller, wherein the clutch controller is used for receiving power supply signals of a plug-in mode or a battery mode; the controller is used for receiving signals input by a driver via a handle and used for controlling speed of each hydraulic execution component, calculating control signals of each hydraulic execution component and transmitting the signals to the frequency converter; and the frequency converter is used for taking electricity from the plug-in mode or the battery mode via the clutch controller, converting the electricity into voltage of each servo motor connected to the frequency converter, controlling size and direction of rotation speed of each servo motor, controlling size and direction of output flow of the two-way constant-displacement pumps connected to the frequency converter and finally controlling the speed of each hydraulic execution component. Through the fully-electrically-driven hydraulic excavator power system, internal combustion engines which are widely used at present are eliminated; the advantage of high power of a hydraulic system is exerted; and through adoption of a volume control mode, the effective combination of energy conservation and emission reduction is achieved.