Vehicle steering wheel automatic centering unit, vehicle with same and automatic centering method

The invention provides an automatic centering unit for automatically centering steering wheels of a vehicle. The automatic centering unit is characterized by comprising a hydraulic steering gear, an electro-hydraulic proportional valve group, an angle sensor and a controller; as the controller is programmable, a control program is set, and an algorithm function of the control program is Z equal to g (X,Y); and the controller is used for receiving an angle signal from a front axle sensor and controlling the electro-hydraulic proportional valve group according to a selected steering mode to drive a steering oil cylinder to move, thereby realizing the control requirements for a corner of a rear wheel when the vehicle is in a steering mode, and the steering mode is switched. The invention further relates to a vehicle comprising the automatic centering unit, in particular to an engineering vehicle or a wheel type crane. In addition, the invention further relates to a method for automatically centering the steering wheels of the vehicle.