Title :
A phase-measurement offset compensation technique suitable for automation
Author :
Wagdy, Mahmoud Fawzy ; Lucas, Michael S.P.
Author_Institution :
Dept. of Electr. & Comput. Eng., Northeastern Univ., Boston, MA, USA
Abstract :
DC offsets degrade the measurement of phase between two sinusoidal signals when the zero-crossing method is used. To improve the measurement accuracy, a novel offset compensation technique is introduced that is suitable for use in automated instruments. The technique is based on calculating the average value of two phase angles: one is between the offset crossings of increasing signals and the other is between crossings of decreasing signals. Thus, it is possible to dispense with the offset-minimization-dedicated hardware that exists in conventional phase meters at the expense of added software. Some hardware limitations and design considerations are discussed.
Keywords :
compensation; computerised instrumentation; computerised signal processing; phase measurement; DC offsets; automation; average value; computerised signal processing; offset crossings; phase angles; phase-measurement offset compensation; sinusoidal signals; zero-crossing; Accuracy; Computers; Detectors; Hardware; Image edge detection; Noise; Phase measurement;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
DOI :
10.1109/TIM.1987.6312778