Quantitative thermographic diagnostics of electric motors for reducing energy demand.

摘要

Excessive electrical demand leads to challenges in electrical supply and global climate change. Reductions of carbon dioxide emissions are necessary to mitigate the consequences of global climate change. Approximately thirty percent of the carbon dioxide comes from fossil fuels burned to generate electricity; therefore, the efficient use of electricity reduces carbon dioxide emissions. Estimates place electricity used by motors at 65%, so efficient use of motors is an opportunity to avoid carbon dioxide emissions. Traditionally motor efficiency is measured using a dynamometer and an electrical power meter; this is not practical in an industrial setting without process interruption. Therefore, a non-invasive technique for measuring in-situ motor operation is needed.;The results of quantitative thermography in the laboratory indicate that accurate determination of efficiency of motors at loads over 60% and the identification of under loaded motors is possible. The results of quantitative thermography in industry show the accuracy of the efficiency is better than 2.5% based on the average variance of the heat transfer coefficient at 12.9%, which compares favourably to standard laboratory methods of measuring motor efficiency. The industrial trial shows the potential to reduce electrical demand of the motors, and their carbon footprint, by an average of 12%. Additionally, motor changes based on quantitative thermography have a positive net present value using a 20% required rate of return, medium risk, based on electrical savings and carbon dioxide avoidance. Extrapolating the results of this quantitative thermography industrial trial indicates that wide spread use of quantitative thermography has the potential to reduce world electrical demand by 8%, with a carbon dioxide equivalent avoidance of 470 Mt/y.;Quantitative thermography is created and developed in this work as a non-invasive method to measure in-situ heat transfer coefficients and motor operation (load and efficiency). Inefficiencies, either based on motor load or equipment degradation, are identified by comparing the measured waste heat to the expected waste heat values. The method for quantitative thermography is validated in an electro-mechanical lab and applied in an industrial setting.