Geomagnetic Disturbances (GMD) is a phenomenon which is widely studied due to its impact on the operation of the electrical grid. Power transformers, which are a critical component of the electrical grid, are particularly susceptible to GMD and the resulting geomagnetically induced currents (GIC) which flow through transmission lines and transformer terminals connected to the ground. While the effects of GMD events on power transformers are generally known, advancements in modeling have improved the understanding of the susceptibility of power transformers to these effects. Establishing power transformer capability while under GMD allows asset owners to plan and reliably operate their power transformers during these events.
IEEE PES Transactions Papers
- "Calculation Techniques and Results of Effects of GIC Currents as Applied to Large Power Transformers"
- R. Girgis and K.O. Chung-Duck, IEEE Transactions on Power Delivery Vol. 7, No. 2, pp. 699 – 705, April 1992
- "Geomagnetic Disturbance Effects on Power Systems"
IEEE Transmission and Distribution Committee Work Group on Geomagnetic Disturbances and Power System Effects, IEEE Transactions on Power Delivery Vol. 8, No. 3, pp. 1206 – 1216, July 1993
- "GIC Occurrences and GIC Test for 400 kV System Transformer"
M. Lahtinen and J. Elovaara. IEEE Transactions on Power Delivery, Vol. 17, No. 2, pp. 555 – 561, April 2002
- "Simulation of Transformer Hot-Spot Heating due to Geomagnetically Induced Currents"
L. Marti, A. Rezaei-Zare, and A. Narang. IEEE Transactions on Power Delivery, Vol. 28, No. 1, pp. 320 – 327, Jan 2013
- ”Study of the Acceptable DC Current Limit in Core Form Power Transformers"
P. Picher, L. Bolduc, A. Dutil, and V.Q. Pham. IEEE Transactions on Power Delivery, Vol. 12, No. 1, pp. 257 – 265, Jan 1997
- ”Characteristics of transformer exciting current during geomagnetic disturbances"
R.A. Walling and A. Khan. IEEE Transactions on Power Delivery, Vol. 6, No. 4, pp. 1707 – 1714, Oct 1991
- "Geomagnetically induced current effects on transformers"
P.R. Price. IEEE Transactions on Power Delivery, Vol. 17, No. 4, pp. 1002 – 1008, Oct 2002
- “Behavior of Single-Phase Transformers Under Geomagnetically Induced Current Conditions"
A. Rezaei-Zare. IEEE Transactions on Power Delivery, Vol. 29, No. 2, pp.916-925, Apr 2014
- "Reactive Power Loss Versus GIC Characteristic of Single-Phase Transformers”
A. Rezaei-Zare. IEEE Transactions on Power Delivery, Vol. 30, No. 3, pp.1639-1640, Jun 2015
- “Analysis of Three-Phase Transformer Response due to GIC Using an Advanced Duality-Based Model”
A. Rezaei-Zare, L. Marti, A. Narang, A. Yan. IEEE Transactions on Power Delivery, Vol. 31, No. 5, pp.2342-2350, October 2016
IEEE Transmission and Distribution Conference Papers
- "Effects of GIC on Power Transformers and Power Systems"
R. Girgis and K. Vedante, IEEE Transmission and Distribution Conference, Paper #TDC.2012.6281595, Orlando, FL, May 2012
- "Evaluation of GIC Thermal Capability of Power Transformers – Part I: Core Form Transformers"
R. Girgis and M. Bernesjo, IEEE Transmission and Distribution Conference, Paper #2022TD0120, New Orleans, LA, 2022
- "Evaluation of GIC Thermal Capability of Power Transformers – Part II: Shell Form Transformers"
R. Girgis and M. Bernesjo, IEEE Transmission and Distribution Conference, Paper #2022TD0121, New Orleans, LA, 2022
IEEE PES Conference Papers
- "A Process for evaluating the degree of susceptibility of a fleet of power transformers to effects of GIC"
R. Girgis, K. Vedante, and G. Burden, IEEE PES Conference, Chicago, Il, Paper #2014TD0380, July 2014
- "Evaluation of Thermal Impact of GIC on Tertiary Windings of Large Power Transformers"
R. Girgis, M. Bernesjo, I. Grant, and G. Kobet, IEEE PES Conference, Virtual Meeting, Paper # 2020PESGM1065, August 2020
- "Methodology for evaluating the impact of GIC and GIC capability of power transformer designs"
R. Girgis and K. Vedante, IEEE Power & Energy Society General Meeting Proceedings, Vancouver, Canada, Paper #PESGM.2013.6672911, pp. 1–5, July 2013
- "Experience with Impact of GIC on Noise Performance of Large Power Transformers"
R. Girgis, M. Bernesjo, S. Hodgdon, J. DeMay, B. Arritt, L. Van Der Zel, IEEE Power & Energy Society General Meeting Proceedings, Paper #2019PESGM1965, Atlanta, GA, USA, July 2019
- “Accurate Calculation of VAR Demand for a fleet of Power Transformers”
Girgis R., M. Bernesjo, L. Hozempa, C. Pilch, and C. Fraley. IEEE Power & Energy Society General Meeting Proceedings, Paper #2022GM1826, Denver, CO. USA, July 2022
Impact of Geomagnetically Induced Current (GIC) on Power Transformers & Power Systems
IEEE-PES General Meeting Session: July 2022
Speakers: M. Olson, K. Patil, A. Commander, T. Hartmann, A. O’Malley, R. Girgis, G. Hoffman, and S. Digby
The Panel Session at the 2022 IEEE PES GM Conference covered the following Topics:
- NERC’s TPL007 Standard, its requirements, Tasks, and Timeline
- System Modelling and Calculation of GIC Flow in Power Systems
- GIC Transformer Fleet Assessment – Case study
- Other Utility experiences with GIC Fleet Assessment
- GIC Thermal Capability of Power Transformers
- FirstEnergy’s experience with GIC System Study
- On-Line Monitoring of GIC and its Thermal impact in Real Time
- Overview of IEEE GMD Guide; C57.163-2016 and planned updates
Geo-magnetically Induced Current: Effects on Power Transformers and the Power System; Monitoring, and Potential Mitigation
IEEE-PES Tutorial: 2012
Speaker: E. Bernabeu, D. Fugate, R. Girgis and F. Koza
Geo-magnetically induced currents (GIC) flow into power transformers through the neutral. These currents can cause core saturation depending on the magnitude of the GIC and the design of the transformer. However, there is some misconception in the electric power industry today that GIC currents have caused and will cause significant damage to large and medium power transformers installed on power grids. The purpose of this tutorial is to present the true effect of GIC on power transformers and power systems, and the available methods to monitor GIC, as well as mitigating its effects.
This tutorial has four parts. First, factors that influence the susceptibility of power transformers to overheating due to GIC will be explained. This will be followed by a presentation on simulating GIC flow in power systems and the impact of the resulting MVAR demands and magnetizing current harmonics on voltage stability, system protection, and other power system components. The third part of the tutorial will include an overview of GIC monitoring, typical time-scale & magnitude characteristics of GICs, the type of sensors that are required (and sensor locations relative to the monitored transformer), and the data acquisition hardware used to capture and transmit GIC information. The last part of this tutorial will deal with the work of a task force (TF) formed by NERC to study all aspects of Geomagnetic Disturbances (GMD). Finally, representatives of power utilities in North America who will be attending the tutorial will be given the opportunity to share with the attendees.