Study On Photo-Electric System Of High-Speed Rotation Shaft Torque Measurement

Torque of high speed rotary mechanical equipment is the key factor of the whole system safety and efficiency. Conclusion has been drawed that the existing torque measuing instruments are not fit for high rotate speed torque measuring through investigation.This paper studies on torque measurement of high speed rotation shaft, which involves these aspects: development situation at home and abroad and principles of torque measurment; principle of photoelectric torque measuring sensor, structure design of the whole system, and parameters calculating; research and design of hardware circuit of the system; design of software; experiment data processing, error sources analyse, and presenting advice for system enhance.Considering principle, the system adopts photoelectric measuremnet. Under the condition of laboratory, two gear dial are fixed at both sides of the shaft measured, torque can be got form relative angle displacement of the two gear dial. Time-average method has been applied in the design of system to avoid measuring rotate speed, in the purpose of cutting error resources.Considering measurement circuit, FPGA (Field Programmable Gate Array) is used as the main control chip, measure speed, accuracy and reliability are increased, and volume of the system is decreased. Programme of FPGA and clock can be changed for different require for rotate speed range, accuracy, and measure speed, it enhanced the flexibility of the system.Considering computer software, Visual C++ is chose as the development flatform. The software can display the measuring results real-time in form of both datd and chart, also can calculate standard deviation and error, store the results.The photoelectric torque system designed for high rotation speed shaft, can measure torque of elastic shaft with rotate speed up to 105r/min. The characters of the system are far rotate speed range, high accuracy, high measuring speed, small volume. And it works reliably. The software can measure real time, process and store datd fast, display analysing result with diagram. It has been proved by system test that the relative error is less than 1.2%, the measure range is 0~180 degree to phase difference, and the accuracy can reach 0.05 degree which achieves design require.