Sugar Concentration Measurement System Using Radiofrequency Sensor

A sugar solution measurement system was developed based on the dielectric properties of the sucrose molecule. An ac conductivity and tan δ study as a function of the frequency was performed to find the suitable frequency range for the measuring system. The results indicate that it is possible to obtain a better response of the sensor using the frequencies as the maxima peak in tan δ appears. Developed setup for sucrose solution was appropriate to measure in a 0.15 to 1 g/mL range with an experimental error of about 3%. The proposed system improves the measurement time over some other methods.

A Sensor System for Detecting and Localizing Partial Discharges in Power Transformers with Improved Immunity to Interferences

The paper reports on the solution, principles, and application results related to a system for diagnosing main transformers in power plants via the radiofrequency method. The subject of the diagnostics is the occurrence of partial discharge activity in transformers. The technical solution of the system is characterized in the introductory section of the article. There then follows a description of the operating principle and the implemented novel advanced methods for signal detection and source localization. The results obtained from practical application of the system within the diagnostics of high-power transformers are presented as well. Because ambient electromagnetic disturbance was recognized as a major issue during the system development, novel detection methods were proposed, implemented, and verified. The principal approach utilizes an external radiofrequency sensor to detect outer impulse disturbance and to eliminate disturbance-triggered acquisitions, and it also ensures direct real-time visualization of the desired impulse signals. The ability of weak signal detection was verified via artificial impulse signal injection into the transformer. The developed detection methods were completed with localization techniques for signal source estimation. The desired impulse signal was detected and localized during full operation of the main transformer, despite the presence of strong electromagnetic interference.

Radiofrequency method for measurement of liquefied petroleum gas mass in the tank of a gas tank truck

Radiofrequency method for measurement of liquefied petroleum gas mass under overload from gas tank trucks into tanks of automotive gas-filling stations and gas-holders is considered. Experience of application of radiofrequency measurement system SU-5D-MASS for mass measurement of various liquids and gas condensates under their storage in reservoirs and pumping through pipelines is taken into account. Optimization of measurement system is suggested implying equipment of 1–2 gas tank-cars by Coriolis flow-meters and radiofrequency sensor of liquefied petroleum gas mass in the tank of a gas tank-car while other gas tank-cars are equipped only such a mass sensor. New approach of calibration of tanks of gas tank trucks and automotive gas-filling stations is suggested.

Bio-Impedance Non-Contact Radiofrequency Sensor for the Characterization of Burn Depth in Organic Tissues

flat circular transmission-line based 300 MHz resonator is implemented for the noncontactassessment of burn depths in biological tissue. Used as a transmit-and-receive sensor, it isplaced here at a 2 mm distance from organic material test samples (pork fillet samples) which havebeen previously heated on one face in various heating conditions involving various temperatures,durations and procedures. Data extracted from the sensor by means of a distant monitoring coilwere found to clearly correlate with the depth of burn observed on the tissue samples (up to 40%sensor output changes for a 7 mm burn depth) and with the heating conditions (around 5% sensoroutput changes for 5.5 mm burn depth obtained at 75 °C or 150 °C). These results open the way tothe development of easy to implement burn assessment and monitoring techniques, which could beintegrated in wearable medical dressing-like monitoring devices.