| With the level of industrialization, science and technology keeping on developmentand the urbanization processing in China, the needs for infrastructures related withindustrial and civil construction, hydraulic and hydro-power engineering, mineexploitation increasing rapidly, so hydraulic excavator as a main mechanical equipmentin these projects is becoming more and more important. But it is difficult to dieselengine has been working in the area of high efficiency and bad emissions as a result ofthe complex condition. Due to nationwide fog haze days appear especially in Januarythis year, more and more people pay attention to environmental issue. In view of thehybrid technology play an important role of energy saving and emission reduction inautomobile industry, this paper will conduct a related research on hybrid technology forthe hydraulic excavator.After the advantages and disadvantages of three types hybrid drive structure havebeen contrasted, and the work condition of hydraulic excavator is frequent changes,eventually a Series-parallel hybrid system in order to adapt to the changeful conditionand improve the energy utilization of diesel engine. Then on the basis of a hydraulicexcavator SY75C-9, the parameters for the key components of the hybrid system werecalculated and determined. A matching energy management strategy has to been makefor the sake of truly achieving energy saving. Due to Series-parallel hybrid’s flexibledriving structure and the changeful conditions, the energy management method ofmulti-mode layer is put forward. The woke mode is divided to two level mode of seriesand parallel, and then each primary mode is subdivided into several basic mode.According to the mathematical model of the main dynamic element, Series-parallel typepower system structure is established. With the engine work in the fuel small area as objective, the simulation model is established and performed by using SimulationX.Final simulation results show that the engine not only works more smoothly but alsoachieve the improvement of fuel economy by comparing with the traditional hydraulicexcavator up to22%. |
