Research on the regenerative braking control strategy for secondary regulation hydrostatic transmission excavators

The secondary regulation hydrostatic transmission technology is applied to the wheel excavator walking device to improve the fuel economy and emissions. A new braking control strategy is proposed based on the analysis of the characteristics of excavator braking and high power density of hydrostatic transmission technology. As to deal with the robust control problems against parameter uncertainty and load disturbance, Sliding mode control method based on the combinational approaching rate is used to design the controller of hydraulic pump/motor. Finally the simulation results shown that brake control system reasonably distributes the front and rear torque, regenerative braking torque and traditional friction braking torque, effectively regenerates braking energy under the premise of safety brake.