Torque is the rotary dynamic system in one of the most frequent need to test parameters, usually we use the torque sensors to achieve rotation torque value measurement in power system. In the process of distance measurement, strain and strain electrical measuring and wireless telemetry is a priority in two ways.

Torque test detection means for strain electrical measuring technology more mature, it has high precision, fast frequency response, good reliability and long service life, etc. Will be dedicated torsion strain gauge with strain adhesive on the measured elastic shaft, and the strain bridge, if provided to strain bridge work power to test the elastic shaft torsion electrical signals. This is the basic of torque sensor model. But on the power transmission system, the most pressing problem is the strain on the body of revolution of the bridge bridge voltage input and signal output how to reliably detect the strain transfer between rotating and stationary parts, typically with conductive slip ring. Due to the conductive slip ring are friction contact, so inevitably there is wear and fever, thus limiting the axis of rotation speed and the service life of conductive slip ring. And as a result of fluctuations caused by contact with unreliable and cause torque sensor even great error in the measurement is not successful.

In order to overcome the defects of the conductive slip ring, another way is to adopt the method of radio telemetry: will be on the axis of rotation torque strain signal amplification and V/F conversion into frequency signal, through the carrier modulation with the method of the radio transmitting fired from the axis of rotation to the axis, with radio reception method, can get axis torsion signal. The axis of rotation on the energy supply is fixed on the axis of rotation of the battery. The method for remote sensing torque sensor. Telemetry torque sensor successful is to overcome the two defects of electrical slip ring, but there are also three deficiencies, one: vulnerable to use on-site electromagnetic interference; Second: the battery power is, so can only short-term use. Third: as the attached on the axis of rotation, easy cause high speed dynamic balance problems. In a small range and small diameter shaft is more prominent.

Absorb the advantages of various methods of digital torque sensor and overcome the defects, the strain sensor is designed on the basis of the two groups of rotating transformer, has realized the transmission of the non-contact energy and signal. And do the torque signal transmission has nothing to do with whether the rotation, has nothing to do with speed size, has nothing to do with the direction of rotation.