Design And Experimental Study Of Power Consumption Measurement System For High Stubble Returning And Tillage Machine

The straw giving back farmland by mechanization technique could improve soil physics characters and fertility conditions, increase the yield and revenue, which was an important measure of developing the ecological agriculture and achieving agriculture sustained development. As a kind of soil cultivating machine, the high stubble returning and tillage machine could finish burying the straw, crumbling and cultivating the soil, flatting landscape and so on only once time. They had several advantages, such as wide working range, crushing erath evenly, good coverage rate, high working efficiency, operation simply and so on. In addition, they could also grab the farming season, saving labor, which showed great superiority in the field of the straw giving back farmland by mechanization. The rotary knife roller was the main working part of the machine, and its power consumption was an important technical parameter to consider the overall performance and directly affected the overall performance. So designing reasonable and compatible power consumption measurement system to real-time obtain power consumption of rotary knife roll-power in the field that was important, because which could provide important reference value for the structure parameter’s optimal design, rational driver matching, energy saving and consumption reducing of the straw returning and tillage machine.Selecting three high stubble returning and tillage machines as research object, this paper aimed at the problems:for example, their actual power consumption were unclear and relations between motion parameters of rotary knife roller and power consumption were uncertain, according to detection principle of the power consumption, using virtual instrument development platform-LabVIEW (that was developed by National Instruments) to design the power consumption measurement system combined with the hardware platform which included data acquisition card, CKY-810dynamic torque sensor and inductive inductance proximity switch and so on. The system could dynamically and simply detect working power consumption of high stubble returning and tillage machines, and could also show waveforms of torque, rotational speed and power, and save their values.The dynamics simulation for the mechanism composed of torque and universal joint shaft was studied by ADAMS software, at the same time, combining with the actual situation, determined that strength of hollow and square casing of universal joint shaft was weakest; applying formula to make strength check, and calculating that the allowable torque moment [M] was2060.44N-m, which was greater than torque fluctuation maximum1472.5N-m of the hollow square casing; the theory proved that installation scheme of the mechanism composed of torque and universal joint shaft twas rational and feasible.The DF1405digital synthesis signal generator and non-contact digital rotational speed instument were used to conduct power system calibration. Calibration experimental results showed that between the torque values detected by power testing system and the true value corresponding to the signal generator output frequency, the maximum absolute error is0.55N-m, the maximum relative error is0.0893%. Between the speed value detected by power testing system and the true value corresponding to the signal generator output frequency, the maximum absolute error is0.002rad/min, the maximum relative error is0.0016%. Between measured by speed device and the speed value detected by data acquisition program, the maximum absolute error value is0.261rad/min, the maximum relative error is0.0726%. Therefore, the power consumption test system could accurately detect torque, speed signal, and thereby detect dynamic power consumption.In the paper, the composition and configuration of power consumption for the high stubble returning and tillage machine for both paddy and dry fields were analyzed, and no-load experimental study was also conducted. The test results concluded that the no-load torque range of rotary knife roller for paddy and dry fields was19.528N· m to24.965N· m, and no-load power range was0.374kW to1.243kW that accounted for0.53%to1.78%of the total kinetic power of the tractor.Selecting power consumption and operating quality as evaluating indicators, Using the high stubble returning and tillage machine for both paddy and dry fields with real-time measurement system, field experiment about power consumption was conducted in the dry lands that late rice fields was dried in the sun after harvest. Three main factors influencing the power consumption that were the tillage depth and rotary speed of knife roller as well as the forward speed of the machine were evalutated with the L9(34) orthogonal test. Through range analysis, the factor that had significant influence on power consumption was the tillage depth, next was the forward speed of the machine, and the rotary speed of knife roller had less influence. Results of the field tests showed that the better operation conditions were that the rotary speed of knife roller was335r/min, the tillage depth was185mm, the forward speed of the machine was3.35km-h-1m/s, the average power consumption was52.53kW in this condition when field tests meet the agrotechnical requirements and its rate of straw burying reached96.2%.