Remote measurement calibration in power system

Abstract

Power system reliability and economy of operation require accurate measurements of current, voltage, real and reactive powers. These measurements are transmitted to a control center of a power system for monitoring, display, and use in power system real-time analysis. The number of measurements is in thousands. Routinely field technicians must calibrate transducers and/or determine other sources of metering errors. Due to the large number of measurements and the time required to check each individual measurement, field calibration procedures are impractical, expensive, and not timely. There has been a need for a more efficient approach to measurement calibration and identification of defective instruments. This paper describes an approach which meets the need. The collection of measurements over time are used to correct for systematic errors, (caused by instrument transformers, transducers, secondary leads between these devices, analog-digital converters, and the scaling procedure). The volts, watts, and vars scales are then adjusted to compensate for these errors, thus providing more accurate measurements