Hydraulic system and wind turbine generator provided therewith

摘要

There is provided a hydraulic pump startup control device in a hydraulic system, which avoids an overloaded state at startup to enable low-temperature, fast startup and maintaining of the temperature with low-cost means in order to improve low-temperature startability. A bypass path 19 is placed in parallel with a hydraulic main line from a hydraulic tank, and the downstream of the bypass path is made merged with the hydraulic main line. A bypass valve 3 that opens or closes the bypass path is provided in the bypass path, and a pressure sensor is provided in the inlet of a hydraulic unit in the hydraulic main line. Further, a control device 10 to which a pressure detection value in the hydraulic main line is input from the pressure sensor to open the bypass valve based on the pressure detection value upon startup of the hydraulic unit. The control device repeats on-off control to circulate oil in the bypass path while keeping the pump discharge pressure and the flow rate to open the bypass path at startup so that the actuation power of the hydraulic unit will become the maximum in order to rise the hydraulic temperature of the hydraulic main line.