Engineering vehicle and hydraulic driving system of walking system thereof

The utility model discloses a hydraulic driving system of an engineering vehicle walking system, which comprises a variable pump connected with a power device, and the variable pump is provided with afirst port and a second port which are used for discharging return oil; the variable displacement motor is used for being connected with a gearbox and comprises a first oil inlet/outlet communicatedwith the first port and a second oil inlet/outlet communicated with the second port; and the displacement control loop is used for controlling the displacement of the variable displacement motor according to the change of the working load, an oil inlet of the displacement control loop is selectively connected with the first port and the second port, and an oil outlet of the displacement control loop is connected with a variable displacement mechanism of the variable displacement motor. According to the hydraulic driving system, gear shifting can be conducted while the variable displacement motor has power, and load gea