Contents I. Introduction
Current is an important monitoring quantity for equipment and power networks. Wide range and broadband current measuring and sensing technology is very important for the construction of smart grid.
Abstract:
If current transformer (CT) is saturated in operation, it will lead to incorrect current measurements and may cause relay maloperation, which can greatly threaten the saf...Show MoreMetadata
Abstract:
If current transformer (CT) is saturated in operation, it will lead to incorrect current measurements and may cause relay maloperation, which can greatly threaten the safety of power grid. This paper analyzed the basic measuring characteristics of the proposed novel current transformer based on virtual air gap. This method can successfully compensate the distorted secondary current and expand the measuring range. Based on the simplified magnetization curve model, its working state is divided into linear working state, partially saturated working state and saturated state. Furthermore, its basic measuring characteristics are deducted theoretically. The theory is verified by FEM simulation results and prototype experiments. The difference between this method and other methods is also discussed. Compared with CT, this method adopts partial-gapped magnetic core and magnetic field sensor (MFS) for current reconstruction. When it works in rated state, this method is like a normal CT. Once the primary current saturated the small section core, it will be like a virtual gap, making the whole core more difficult to saturate and allowing the measurement of leakage flux. It has the advantages of simple and compact structure and can be embedded into the electronic current transformer (ECT) system. In this sense, it can have a good application prospect. The main limitation is the requirement of high permeability material for accuracy performance.
Published in: IEEE Transactions on Power Delivery ( Volume: 38, Issue: 1, February 2023)
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1.
Instrument Transformers Part 2: Additional Requirements For Current Transformers, 2012.
2.
A. Cataliotti, D. Di Cara, P. A. Di Franco, A. E. Emanuel and S. Nuccio, "Frequency response of measurement current transformers", Proc. IEEE Instrum. Meas. Technol. Conf., pp. 1254-1258, 2008.
3.
M. Stanbury and Z. Djekic, "The impact of current-transformer saturation on transformer differential protection", IEEE Trans. Power Del., vol. 30, no. 3, pp. 1278-1287, Jun. 2015.
4.
E. Hajipour, M. Vakilian and M. Sanaye-Pasand, "Current-transformer saturation compensation for transformer differential relays", IEEE Trans. Power Del., vol. 30, no. 5, pp. 2293-2302, Oct. 2015.
5.
S. Sanati and Y. Alinejad-Beromi, "Avoid current transformer saturation using adjustable switched resistor demagnetization method", IEEE Trans. Power Del., vol. 36, no. 1, pp. 92-101, Feb. 2021.
6.
J. Guan, Z. Hao, W. Chen, Z. Liu and X. Yu, "Compensation of current transformer saturation based on improved ESPRIT algorithm", Proc. IEEE 16th Int. Conf. Environ. Elect. Eng., pp. 1-4, 2016.
7.
L. Ren, Z. Hao and B. Zhang, "A novel algorithm applied in the transient saturation of current transformer", Proc. IEEE Int. Conf. IEEE Region 10, pp. 1-4, 2013.
8.
R. A. Allah, S. Moussa, E. H. Shehab-Eldin and M. N. G. Hamed, "Advanced detection and compensation scheme for current transformers saturation", Proc. 11th Int. Middle East Power Syst. Conf., pp. 481-486, 2006.
9.
"Gapped core current transformer characteristics and performance", IEEE Trans. Power Del., vol. 5, no. 4, pp. 1732-1740, Oct. 1990.
10.
Y. Kang, J. Park, B. Lee, S. Jang and Y. Kim, "Compensation of an air-gapped current transformer considering the hysteresis characteristics of the core", Proc. IET 9th Int. Conf. Develop. Power Syst. Protect, pp. 495-500, 2008,.
11.
M. Davarpanah, M. Sanaye-Pasand and R. Iravani, "A saturation suppression approach for the current transformer—Part I: Fundamental concepts and design", IEEE Trans. Power Del., vol. 28, no. 3, pp. 1928-1935, Jul. 2013.
12.
M. Davarpanah, M. Sanaye-Pasand and R. Iravani, "A saturation supression approach for the current transformer—Part II: Performance evaluation", IEEE Trans. Power Del., vol. 28, no. 3, pp. 1936-1943, Jul. 2013.
13.
M. G. Wath, P. Raut and M. S. Ballal, "Error compensation method for current transformer", Proc. IEEE 1st Int. Conf. Power Electron. Intell. Control Energy Syst., pp. 1-4, 2016.
14.
T. Zheng et al., " Fast in situ demagnetization method for protection current transformers ", IEEE Trans. Magn., vol. 52, no. 7, Jul. 2016.
15.
D. C. Yu and J. C. Cummins, "Correction of current transformer distorted secondary currents due to saturation using artificial neural networks", IEEE Trans. Power Del., vol. 16, no. 2, pp. 189-194, Apr. 2001.
16.
R. Medeiros and F. Costa, "A wavelet-based transformer differential protection with differential current transformer saturation and cross-country fault detection", IEEE Trans. Power Del., vol. 33, no. 2, pp. 789-799, Apr. 2018.
17.
B. M. Schettino, C. A. Duque and P. M. Silveira, "Current-transformer saturation detection using savitzky-golay filter", IEEE Trans. Power Del., vol. 31, no. 3, pp. 1400-1401, Jun. 2016.
18.
T. Ji, M. Shi, M. Li, L. Zhang and Q. Wu, "Current transformer saturation detection using morphological gradient and morphological decomposition and its hardware implementation", IEEE Trans. Ind. Electron., vol. 64, no. 6, pp. 4721-4729, Jun. 2017.
19.
E. Hajipour, M. Vakilian and M. Sanaye-Pasand, "Current-transformer saturation compensation for transformer differential relays", IEEE Trans. Power Del., vol. 30, no. 5, pp. 2293-2302, Oct. 2015.
20.
K. Kumar, G. B. Kumbhar and S. Mahajan, "A new efficient algorithm to detect current transformer saturation", Proc. IEEE Power Energy Soc. Gen. Meeting, pp. 1-5, 2016.
21.
P. Orr, P. Niewczas, A. Dysko and C. Booth, "FBG-based fiberoptic current sensors for power systems protection: Laboratory evaluation", Proc. 44th Int. Universities Power Eng. Conf., pp. 1-5, 2009.
22.
L. Li, Q. Han, Y. Chen, T. Liu and R. Zhang, "An all-fiber optic current sensor based on ferrofluids and multimode interference", IEEE Sensors J., vol. 14, no. 6, pp. 1749-1753, Jun. 2014.
23.
Y. Ouyang, J. He, J. Hu, G. Zhao, Z. Wang and S. X. Wang, "Contactless current sensors based on magnetic tunnel junction for smart grid applications", IEEE Trans. Magn., vol. 51, no. 11, Nov. 2015.
24.
S. Tumanski, Handbook of Magnetic Measurements, Boca Raton, FL, USA:CRC Press, pp. 159-244, 2011.
25.
V. Molcrette, J.-L. Kotny, J.-P. Swan and J.-F. Brudny, "Reduction of inrush current in single-phase transformer using virtual air gap technique", IEEE Trans. Magn., vol. 34, no. 4, pp. 1192-1194, Jul. 1998.
26.
S. Magdaleno and C. P. Rojas, "Control of the magnetizing characteristics of a toroidal core using virtual gap", Proc. Electron. Robot. Automot. Mech. Conf., pp. 540-545, 2010,.
27.
X. Chen, Z. Wang, Z. Yu and B. Chen, "A novel compact structure of the three-phase virtual air gap controllable reactor", Proc. IEEE Magn. Conf., 2015.
28.
Instrument Transformers Part 100: Guidance for Application of Current Transformers in Power System Protection, 2017.
29.
N. Kondrath and M. K. Kazimierczuk, "Bandwidth of current transformers", IEEE Trans. Instrum. Meas., vol. 58, no. 6, pp. 2008-2016, Jun. 2009.
30.
P. Poulichet, F. Costa and E. Labour, "A new high-current large-bandwidth DC active current probe for power electronics measurements", IEEE Trans. Ind. Electron., vol. 52, no. 1, pp. 243-254, Feb. 2005.
