Research On Energy Saving Technology Of Boom And Turntable Of Hydraulic Excavator Under Compound Action

Construction machinery industry has a good development prospect,and the hydraulic excavator as its main models,has a huge market demand.However,the environment of hydraulic excavator is not friendly,which makes it to the direction of energy saving and environmental protection.Hydraulic excavator energy saving technology has become a hot spot in the research of construction machinery manufacturers.In order to improve the energy saving effect of the excavator,an energy recovery system of the hydraulic excavator boom and turntable with accumulator and battery as the energy storage device is proposed,which makes the energy recovery achieved when the boom down and the rotary brake compound action.The scheme design,component selection and parameter matching,model establishment and contrast simulation analysis,as well as parameter influence and experimental verification of the system are studied.The main contents of this thesis can be divided into the following sections:1.The research status of energy saving technology of hydraulic excavator is introduced.This thesis analyzed the research status of energy saving technology of excavator's hydraulic system,boom,turntable and multi-working device,and then determines the research content of this subject.2.The system is designed.The scheme design of the boom down potential energy recovery module,the turntable brake energy recovery module and the energy storage and release module are carried out.According to the overall design requirements and then integrated the modules,designed electro-hydraulic coordination energy recovery system,the system design is completed.3.The system main component selection and parameter matching.Taking a 7-ton hydraulic excavator as an example,the models and specific parameters of the main components of the boom and turntable,accumulators,recovery motors and generators are matched to prepare for the next system energy saving research.4.Simulation of the system.The system model is established and the parameters are set,and the simulation action and control strategy are worked out.The simulation results show that under the premise of reasonable parameter matching,and compared with recoverable energy,the energy recovery efficiency of rotary brake is 61.3%,the energy recovery efficiency of boom down is 27.3%.The total energy recovery efficiency of the system reached 44.9%,the energy reuse efficiency reached 47.2%,and the energy saving effect was good.Change the energy storage components and build the corresponding system model,simulated and analyzed the hydraulic energy recovery system and the electric energy recovery system,and then compared the results with the original system.5.The influence of key parameters on the energy saving effect of the system is studied.In order to guide the optimization of parameters and improve the energy saving effect of the system,the relationship between the key parameters and the energy recovery of the system is studied on the basis of the simulation research.The influence of the parameters on the energy recovery efficiency of the system is obtained by changing the initial volume and pressure of the accumulator,the displacement of the recovery motor,the presence or absence of the throttle valve and its aperture.At the same time in order to enhance the control performance of the system,the boom and the rotary brake was improved.6.Experimental study on the influence of accumulator on the energy saving effect of system.In order to verify the influence of the key parameters of the accumulator on the energy saving effect of the system,the experimental scheme is designed,the experimental equipment is selected,and the simulation experiment platform is set up according to the actual situation.The experiment is carried out to match the actual parameters of the rotary system of a 4-ton hydraulic excavator.The obtained data are analyzed and the simulation results are verified.