SMART SENSORS FOR A SMARTER GRID BY KAILASH.K AND LAKSHMI NARAYAN.N

WHAT LED US INTO RECOMENDING THIS SYSTEM?? The existing power grid are significantly constrained by the legacy infrastructure and its susceptibility to failure. Existing technologies are not able to provide the insight and information necessary for the grid to evolve. Our proposed system will provide improved visibility and, in turn, increased reliability.

WHAT TECHNOLOGY WE USE? Advanced Sensors Global Positioning System

Layout of our System

THE MAIN COMPONENTS AND THEIR WORKING IN OUR SYSTEM

WIDE AREA MONITORING SYSTEM WAMS employs a technique known as Synchronized phasor measurement. It is based on collecting GPS time-synchronized data from multiple points on a wide area grid to provide real-time analysis of voltage stability on the power network. The synchronized phasor measurements are to be transmitted in real-time to the control centers of the grid system. Control Centers can process and analyze the information to make mission critical decisions to improve system reliability.

SENSORS: The sensor is self powered and designed to be installed live on HV systems up to 765 kV. It consists of a highly accurate, actively compensated split-core CT and an electric field voltage sensor which provides RMS phase and magnitude data over the wire-less link back to the control center. The sensors are mounted directly and easily at the desired monitoring point, this provides a leap forward in technology that immediately contributes to the ability to improve the overall reliability of the power grid. Using this sensor bypasses the existing infrastructure of conventional instrument transformers–based methodology.

Sensor – Schematic Diagram

ACHIEVING ACCURACY The HV sensor acts as the high accuracy reference sensor, known as the primary sensor. The primary sensors are mounted live, one on each phase, on the high voltage bus within a substation. The CT under test provides analog signals for the instrumentation, that is connected to a highly accurate advanced meter. The measurements from the primary sensors are wirelessly streamed and collected by a PC that is simultaneously collecting data from the meter connected to the secondary wiring of the CT under test. The PC compares the GPS time-synchronized data from both the primary sensor and the meter and calculates the error in phase angle and ratio for the CT under test. Having this error information provides insight into the true accuracy of the overall measurements used for grid reliability monitoring. With this information, the accuracy of the CT can be dynamically corrected by programming the advanced meter with the necessary corrections.

Accuracy Achievement - Diagram

CONCLUSION By presenting this paper we have provided a source for better control and accuracy of existing grid monitoring system and thereby provide better information leading to an overall system improvement in grid reliability. The combination of the highly-accurate HV sensor and the ability to improve the overall accuracy of existing monitoring sites provides a solution that increases the visibility for operators controlling the grid.