Comparative Study On Electric Driving And Hydraulic Drive Of Two-wheel Milling Machine

Hydraulic trench cutter has many unique advantages when setting underground diaphragm construction,for example it can constructs deep and high quality trench and also suits much geology safely,Hydraulic trench cutter will takes the place of hydraulic grab machine and rotary drilling rig in order to get great diaphragm walls and meet high construction technology,so it is a important construction equipment dedicated for high quality underground diaphragm walls.it must equip long hydraulic hose with bad thermal conductivity when cutting deep walls,but the hose creates much pressure loss which generates a amount of heat and it makes the machine cost high energy with low efficiency.On the one hand it creates much heat,on the other hand heat dissipation is poor.so thermal balance will be broken to set a new higher thermal balance which brings many defections.Above all,we research electric trench cutter retaining merit but abandoning shortcoming of hydraulic trench cutter.This paper completes the comparison between the electric drive and the hydraulic drive of the two-wheel slot milling machine.at first,the calculation of electric trench cutter is based on parameter of the mall and middle size hydraulic trench cutter which provides torque less than 80 knm.according to mechanical characteristic of the electrical motor,choose the final drive solution by double parallel motor.the speed range is based on the motor mechanical characteristic at every frequency.the transmission ratio is on the basis of the output and input torque ratio and output to the input speed ratio.Secondly,comparing several control strategies of electric drive in order to select the slip frequency vector control method.then set up the module of electric trench cutter in simulation software of MATLAB/simulink.at the same time,Detail design calculation for hydraulic system of trench cutter is achieved for constructing the module of the Variable pump-quantitative motor load sensitive system in simulation software of AMEsim.Finally,complete the comparison main containing governing characteristic,System stability,maximum load resistance,efficiency and system response at limit load between tow machines.On the basis of the theory and simulation results,we get the follow conclusion.first,In order to ensure good output torque we determine the two motor parallel drive program;Determine the speed range according to the mechanical characteristics of the motor at each frequency;Determine the slip frequency vector control method according to the characteristics of the driving load;The load capacity and speed control range of the electric drive system are smaller than that of the hydraulic drive system.Under the constant load condition,the electric drive system and the hydraulic drive system can regulate speed smoothly.Under the variable load condition,the two drive systems have good stability and can maintain constant speed operation.Under the limit load condition,the speed fluctuation of the electric drive system is smaller than that of the hydraulic drive system,and the speed recovery is quickly.The efficiency of the electric drive system when working in the economic zone is greater than that of the hydraulic drive system.