The power of hydraulic system is the pressure of the liquid, which is supplied by the pump. Because the liquid is almost incompressible, the pump continues to supply oil to the closed hydraulic system, so that the oil in the system continues to increase, and can not compress the oil, naturally leading to the pressure in the system increased. The pump is driven by motor, motor is driven by electricity, electricity is the source of hydraulic power. Hydraulic systems convert electrical energy into mechanical energy (motor rotation), mechanical energy into liquid pressure energy, and then (push the actuator) into mechanical energy for work.

The Hydraulic Power Unit (HPU) is used as a fuel supply unit. It is connected to several hydraulic cylinders through an external pipeline system to control the action of multiple sets of valves. The oil tank, the oil pump and the accumulator form an independent closed power oil source system. The oil station can be equipped with a PLC control system that controls all internal hydraulic functions and generates signal and control room (DCS) exchange. Control elements such as hydraulic servo valves are installed directly on the hydraulic cylinder, through which the high-pressure oil is pressed into the cylinder, or from which the high-pressure oil is discharged. Under normal condition, the oil pump supplies oil to the system, automatically maintains the rated pressure of the system, realizes the function of keeping the valve in any position by locking the control valve; under working condition, the hydraulic actuator is controlled by the solenoid valve, and the system command signal makes the solenoid valve move, controls the oil pressure and the energy release of the accumulator, and then controls it.

The cylinder sliding valve drives the valve through the mechanical transmission mechanism, and implements fast closing, normal opening and closing and test control. The high pressure oil cylinder can be fixed on the stem, and can also be used directly as an actuator. The excess hydraulic oil is returned to the station so that the pipeline system can control several parallel valves with one intake pipe and one return pipe. This kind of hydraulic station with special drive technology is used to control the actuator action of main steam valve and steam turbine bypass system. Power units are designed for a variety of applications, such as truck operations in harsh environments, long-term heavy load handling, and other applications requiring high-performance and high-quality products.