Research On Boom Potential Energy-recovery Technology Of Hybrid Hydraulic Excavator

Hybrid technology used in engineering machinery provided an opportunity for thestudy of electrical energy recovery system. The paper studied the recovery methods ofgravitational potential energy of hybrid hydraulic excavator when the boom was dropping.Firstly, the paper analyzed the structure and the working principle of the traditionalelectrical energy recovery system, and then analyzed the feasibility of the programcombined with the characteristics of excavator hydraulic system and the habit of drivingpersonnel. Analysis showed that the conventional energy recovery system was defective,poor energy efficiency. How to achieve coordinated to match the displacement hydraulicmotor and hydraulic valve action is the core problem for the electrical energy recoverysystem to apply in hybrid hydraulic excavator successfully.For the above problem, the paper advanced a pressure stable control strategy thatbased on volume balance and designed the overall structure of the new type of energyrecovery system. Combined with the characteristics of the current hydraulic components,the paper made a study on the specific control algorithms. For the new energy recoverysystem, the capacity of the hydraulic motor will be controlled by the pressure of boomcylinder indirectly when the boom was dropping, matching motor capacity with the actionof hydraulic valve. To model and simulate for the energy recovery system by MATLABsimulation platform, the results of simulation show that the pressure fluctuation of boomcylinder is too large when the boom was dropping. For this problem, advanced twoimproved schemes, they are hydraulic damping and low-pass filtering. Analysis showedthat, the all two programs can play a role in reducing the pressure pulsation. For thehydraulic damping method, orifice diameter and the volume behind it all will affect theeffects damping the pressure pulsation; for the low-pass filtering, with the increase of theorder of the filter part, the effects damping the pressure pulsating is more ideal.Finally, the dissertation studied the handling characteristics and the energy recoveryefficiency of the new energy recovery system. Simulation result showed that: the newenergy recovery system was responsive at speed and had strong anti-jamming capability. Comparative studies on energy recovery efficiency indicated that: compared toconventional systems, the energy recovery efficiency of new energy recovery system wasup to51%, and overcome the defects of conventional energy recovery system that hasenergy recovery action only the specific conditions.