Research On Hydrostatic Driving Energy-saving Technology For Wheel Loader

Loader is one the most important construction machines. It’s working condition is complex, and the load rapid change, the working characteristics often cause mechanical poor performance and low energy efficiency. As people’s awareness of environmental protection and energy saving, the loader with high consumption, high pollution and low energy efficiency to be eliminated is imperative, and hydrostatic drive will undoubtedly become the effective way for loader energy saving research. Hydrostatic drive not only can make composites transmission and hybrid combined, but also has the potential to develop loaders vibration cut, both reduces the energy output and make the energy recovery. fully staffed.In this paper, L550 loader as the research object, research its drive system and work device. Through the use of mechanical hydraulic hybrid drive and hybrid technology to reduce the energy consumption of loader’s drive section;By using the constant pressure network system based on the hydraulic transformer to improve the energy efficiency of the loader working device.The ultimate aim is to improve the energy efficiency of the engine and to improve its overall performance.In this paper, the main work was done as follows:1.This paper describes the current situation and the necessity of energy-saving for loaders,analyzes advantages and disadvantages of various energy-saving technologies and their respective applicable scope.2.This paper adopts mechanical hydraulic hybrid drive energy-saving system,which which will be integrated composite drive. and hybrid.The paper have designed mechanical hydraulic hybrid transmission and analyzed its shifting mechanism,speed characteristics,geometric characteristics,smooth shifting conditions,torque characteristics and hydraulic power flow ratios.While design energy recovery system to recover the energy when loaders brake and under the long slope. The entire system is divided into five operating modes:hydraulic drive, hybrid drive, driving charge pressure, hybrid drive, regenerative braking.In this paper, the key parameters of energy-saving systems were matched theoretical calculation and each gear ratio was determined, key hydraulic components were selected, all that was based on the general parameters of L550 loader.3.The paper analyzed the constant pressure network which is based on the hydraulictransformer and build the system. The new hydraulic system and the traditional one were comparative analyzed from the aspects of working and steering, the new system eliminates a large number of hydraulic valves, reducing the installed power and throttling losses.4.A model of hydraulic drive systems and work equipment systems was established in AMESim, and the hydraulic transformer model was encapsulated for a super component.The paper simulate the traction conditions of drive system and boom lift conditions of work devices, the simulation results show that the design of the system has achieved the expected energy saving effect.