The Development Of Power Measurement And Control System For Tractor Power Take-off Based On LabVIEW

China is a big agricultural country,and agriculture is the foundation of the national economy.The tractor supporting different farm implements can complete all kinds of agricultural work,that greatly emancipate the human labor force,improve agricultural production efficiency.The tractor power output shaft(PTO)as an important part of tractor,its performance is very important,the power test is become one of the test items must to be done for each tractor models.However,the current measurement and control system can only satisfy the performance test for small and medium-sized horsepower tractor,and the accuracy of the test and the degree of automation is low,that cannot meet the needs in the process of the future development of great horsepower tractor test.Therefore,it have great practical significance and market prospects for designing a simple operation,high precision,complete function,high degree of automation of great horsepower tractor pto shaft power test measurement and control system.This topic based on the actual demand,analyzes the significance of design regarding the power test measurement and control system for great horsepower tractor.According to relevant test standard,the concept of the measured parameters in the process of test and measurement principle and experimental process were analyzed,and puts forward the overall design requirements and principles of measurement and control system,and then respectively develops two aspects of the system hardware and software design principle,then made the overall design of measurement and control system framework.Design the measurement and control system from the two aspects of hardware and software according to the design goals.The hardware design part respectively selects the loading motor,constant pressure modules,industrial control machine,acquisition module,sensor,accelerator actuator,fuel consumption meter and so on,and designs the system electric circuit.Software design based on the test process,make the measurement and control system software structure,and the program is divided into the experiment parameters calibration and parameter input before the process of data acquisition,data processing,data storage,data reading,serial port communication,alarm and control module,fault diagnosis to complete the writing of the PC software.After completing system,calibration rotation speed,torque,parameters such as temperature,fuel consumption,to ensure that each parameter measuring results are accurate and reliable.Then finish the test projects of maximum power test,full load variable speed test,the test of variable load at the maximum power at the engine calibration speed and the test of variable load at the maximum power at the PTO standard speed for a 400-horsepower and a 315-horsepower wheeled tractor,the test results show that the measurement and control system can complete the relevant test items of standard requirements,and the system can calculate the relevant several key parameters of standard requirements.It is proved that the design of the tractor power output shaft power test and control system achieves the expected design goal.