Development and applications of advanced intelligent instruments for dynamic torque-speed measurement

This paper focuses on the development of a series of intelligent instruments for dynamic torque/speed measurement. The essential features of the developed intelligent instruments include inexpensive implementation, incorporated multiple measurement functions, automatic data acquisition, enhanced data processing, and a variety of data output interfaces. In comparison to other existing measurement instruments for torques of rotating machines, the proposed measurement instruments, by using the principle of direct measurement of stator torque, are able to readily measure the dynamic torque without installation of traditional load. To guarantee the measurement accuracy of dynamic torque, the effectiveness of the digital filter is controllable according to the speed value. In order to enable the instruments to be more intelligent, the automatic capture of starting torque and speed of the rotating machine is available. At present, the applications of the intelligent instruments have been to induction AC motors, ceiling fans, and high-speed variable frequency motors in the laboratory. The results of evaluation on the implemented intelligent instruments indicate that these intelligent instruments provide a satisfactory level of accuracy and performance, which is suitable for real-time applications