In order to reduce the abnormal speed fluctuation of the hydraulic transport vehicle during the complicated engineering road driving, the D-type half-bridge liquid resistance network is used to separate the motor inlet pressure and the balance valve pilot pressure, and adjusts the actual pilot ratio of the balancing valve opening is adjusted.The pilot pressure was stably controlled to improve the flow stability of the traveling motor.Applying the theory of fluid mechanics, the dynamic mathematical model of the balancing valve was established and the system simulation analysis was carried out.The analysis results show that the application of Dtype halfbridge liquid resistance network can effectively reduce the pilot pressure fluctuation and make the balance valve spool displacement relatively stable.When the diameters of the orifice A and the orifice B both are 0.6 mm, the stability of the flow rate of the traveling motor is increased by 71.6%.