Abstract:  Aiming at the problem of speed characteristic of pump-controlled hydraulic system of surface grinding machine, the S-shaped curve was used to plan the speed of the servo motor and the method of adding damping by accumulator, and it was studied by combining simulation and experiment. Firstly, from the mathematical model of the system, the mathematical model of key components such as servo motor, quantitative pump and damping was established. Then, the simulation model of the system was built by using AMEsim simulation software to inprove the stability of the hydraulic system by using the accumulator and damping in the system with the speed curve of the S-type motor. Finally, in order to verify the reliability of the simulation results, an experimental platform of pump-controlled hydraulic system of surface grinder was built, and the experimental research was conducted for the speed characteristics of load operation, and the experimental data were compared with the simulation results. The research results show that,after the optimization of hydraulic system, the stability and accuracy of the cartridge valve core action, the system pressure fluctuation and the smoothness of the cylinder running speed are improved, and the final speed overshoot is reduced by 79.3%. At the same time, the experimental verification results are basically consistent with the simulation results. The stability of the hydraulic cylinder pressure and the movement speed is improved, and the overall operation quality of the system is improved.
Key words:  surface grinders; pump control system; speed fluctuations; simulation models; AMEsim; cartridge valve core