When speed sensing valve is used to control hydraulic driving system of transporter, low engine speed makes the load sensing system flow unsaturated which causes the actuator velocity is affected by load size. Aiming at the problem, a new method with load independent flow distribution was presented for hydraulic system. Modeling and simulation of the system were carried out by using AMESim; through comparing the calculation results and the simulation curves,the simulation model was accurate and the system principle was correct. The simulation results show that the system can realize steadystate response of the open hydraulic system under different rotating speed, and realize power matching between the engine and load, which is of positive significance to reduce energy consumption.