The Working Characteristics And Energy Consumption Analysis Of The Loader's Fixed/Variable Displacement Hydraulic System

The wheel loader is one construction machinery mainly on earth moving with feather of quick operation,good mobility,flexible operation,and it plays an important role in the development of economy construction,but also a kind of energy intensive machinery.Now with energy problem increasingly prominent,the energy consumption of the loader is also more and more get the attention of people.Now,high efficiency and energy saving has become a development direction in the future.Hydraulic system is the most important part of wheel loader,and its power consumption is the main part of the overall power consumption.Thus improveing the efficiency of the loader hydraulic system have great significance of loader energy saving.This article taking the loader's fixed/variable displacement hydraulic system as an example,using AMESim software to structures its simulation model.Based on this simulation model,we analyse the loader working characteristic in typical working conditions,and calculation its energy consumption.According to the results of calculation and analysis,we optimize energy-consuming components and circuit in particular condition of the system and further reduce the energy consumption of the system.The main contents of this paper are as follows:In chapter 1,The background and significance of research about the loader's fixed/variable displacement hydraulic system is presented.Overview of the current main type and working principle of the hydraulic system of loader which is commonly used.And briefly describes the research status about loader energy-saving hydraulic system.In chapter 2,The structure composition,working principle and the main working parameters of the loader's fixed/variable displacement hydraulic system were introduced respectively.The working mechanism and the structure of the key components load sensing variable pump,multi-way directional valve,pilot valve,flow amplifier valve,working device,which are used in the system were analyzed.This paper establishes AMESim simulation models for each main components,and by comparing simulation results with the product sample test results,to determine the accuracy of the model.In chapter 3,AMESim simulation model of loader's fixed/variable displacement hydraulic system was established.According to the operation condition of the loader working in common,such as: Rotating arm lifting,Unload,Moving arm down conditions and so on,we analyse all the conditions and get the parameters as like changing of Pressure,flow of hydraulic system.And we also analyze special condition that is the work hydraulie system and steering hydraulie system working together.The energy consumption and efficiency of the hydraulic system were calculated,and according to calculation result,we confirm the energy-consuming components and circuit,and this is a strong theoretical basis provided for later system improvement.In chapter 4,AMESim simulation model of the optimization system was established,and according to the operation condition of the loader working in common,such as: Rotating arm lifting,Unload,Moving arm down conditions and so on,we analyse all the conditions and get the parameters as like changing of Pressure,flow of optimization hydraulic system.And we also analyze special condition that is the work hydraulie system and steering hydraulie system working together.The energy consumption and efficiency of the optimization hydraulic system were calculated.At the end,some conclusions in this thesis are summarized and the future research proposals are suggested.