本論文提出並探討電容器切換暫態抑制器。工廠中功率因數改善的電容器會隨著負載變動而投切頻繁，由於電容器切換時會產生暫態過電壓及突入電流(充電電流)，這些暫態現象會縮短電容器的使用壽命及損壞切換開關的接觸點，因此，本文提出非隔離型與隔離型兩種型式之電容器切換暫態抑制器，依據電路拓樸，非隔離型暫態抑制器可分為對稱結構及單相橋式整流兩種電路架構，而隔離型暫態抑制器則僅有一三相橋式整流之電路架構。
本文所提出之電容器切換暫態抑制器係串接於電容器組與電源之間，其不需任何控制或偵測電路便能有效且即時地抑制電容器切換暫態，當電容器投入時，抑制器中的電抗器會自動插入電路中，藉以限制切換暫態。而在抑制暫態後，抑制器則會快速地回復至穩態。在穩態期間，因為直流補償電壓源補償電抗器及二極體導通之電壓降，抑制器將會進行飛輪並形同短路，因此，電容器可視為直接與電源連接，故穩態期間加入抑制器前後之電容電壓及電流波形幾乎相同，且即使電抗器加入於電路中，電容器之端電壓亦不會因此而上昇，故不須提升其設備額定電壓。
基於前述之動作原理，本論文首先提出一個對稱結構型的電容器切換暫態抑制器，此類型之抑制器總共需要六個電抗器來抑制三相電容器之切換暫態。然而，為了減少元件數量及降低穩態功率損失，本文繼而提出一個單相橋式整流型電容器暫態抑制器，此類型之抑制器只需要三個電抗器便能成功地抑制三相電容器之切換暫態，而其穩態功率損失亦相對較對稱結構型抑制器為低。由於直流補償電壓源在單相橋式整流型抑制器中為一關鍵元件，故本論文更進一步地提出一半波整流之電壓源來簡化其電路架構及降低其所造成的損失，而此架構的補償電壓源並不會影響抑制器之原有功能。另外，因遠端變電所高壓市電電容器切換而導致用戶端低壓電容器的電壓放大效應，亦可藉由所提出之單相橋式整流型抑制器予以減緩，避免損壞用戶端之電容器。
為了使抑制器得以彈性運用於不同系統電壓準位，本研究延伸非隔離型抑制器至隔離型抑制器，該抑制器之電路架構為三相橋式整流型，此類型之抑制器僅利用一個電抗器搭配一個三相耦合變壓器便能抑制三相電容器之切換暫態；在三相電力系統中，其功率損失為單相橋式整流型抑制器的1/3倍及約為對稱結構型抑制器的1/6倍。
上述各種型式之電容器切換暫態抑制器的理論推導、實測結果及性能，已於本論文中被驗證與實現。

This dissertation presents and studies the capacitor switching transient limiter (CSTL). Because the loads in industrial plants vary with time, the power-factor correction (PFC) capacitor banks are switched in and out frequently, which will result in transient overvoltage as well as inrush current (charging current). The switching transients will shorten the lifetime of the capacitor bank and damage the contacts of the switching devices. Therefore, this dissertation proposes two kinds of CSTLs: a non-isolated CSTL and an isolated CSTL. According to the circuit topology, the non-isolated CSTL can be divided into a symmetrical structure topology and a single-phase bridge-rectifier topology, while the isolated CSTL has only a three-phase bridge-rectifier topology.
The CSTLs proposed in this dissertation are inserted in series between the voltage source and a capacitor bank. The CSTL can effectively and immediately restrain the capacitor switching transients without any additional control or detection circuit. When the capacitor is energized, the reactor in the CSTL will automatically insert into the circuit to restrict the capacitor switching transients. After suppressing the switching transients, the CSTL will rapidly recover to the steady state. During the steady state, since the DC-compensating voltage source compensates for the voltage drop across the reactor and that across the diodes, the CSTL will freewheel and act as a short circuit. Hence, the capacitor appears to connect directly to the voltage source, and the steady-state voltage and current waveforms of the capacitor before and after inserting the CSTL are almost identical. Moreover, even though the reactor is used in the circuit, no voltage rise appears across the terminals of the capacitor, and thus it is not necessary to upgrade the voltage rating of the capacitor.
Based on the aforementioned operation principle, a symmetrical-structure type CSTL (SS-CSTL) is proposed first and this kind of CSTL requires six reactors to restrain the three-phase capacitor switching transients. However, to reduce the number of components and steady-state power loss, a single-phase bridge-rectifier type CSTL (BR-CSTL) is proposed next and it requires only three reactors to successfully suppress the three-phase capacitor switching transients. Moreover, the steady-state power loss resulting from the single-phase BR-CSTL is less than that of the SS-CSTL. Since the DC-compensating voltage source is a key component in the single-phase BR-CSTL, in this dissertation a half-wave rectifying voltage source is further proposed as a compensating voltage source to simplify its circuit configuration and reduce its power loss. Also, the proposed half-wave rectifying compensating voltage source will not affect the original function of the CSTL. In addition, the voltage-magnification effect on the customer’s low-voltage capacitor, which occurs due to the switching of the high-voltage utility capacitor in the remote substation, can also be mitigated by the proposed single-phase BR-CSTL, thus avoiding damage to customers’ capacitors.
For the purpose of flexibility in the use of different levels of system voltage, this research extends the limiter from the non-isolated CSTL to the isolated one, which is a three-phase bridge-rectifier type CSTL. The three-phase BR-CSTL uses only one reactor combined with a three-phase coupling transformer to restrain the three-phase capacitor switching transients. In a three-phase power system, the power loss resulting from the three-phase BR-CSTL is one-third comparing with the single-phase BR-CSTLs and is around one-sixth that of the SS-CSTLs.
This dissertation carries out theoretical analysis of each proposed CSTL, and experimental results have verified the performance of each type of CSTL.

[1] R. Natarajan, Power System Capacitors. New York: Taylor & Franics, 2005.
[2] T. A. Short, Electric Power Distribution Handbook. Boca Raton: CRC Press, 2004, pp. 269–310.
[3] T. Gonen, Electric Power Distribution System Engineering. McGraw-Hill Press, 1986, pp. 452–499.
[4] IEEE Guide for Application of Shunt Power Capacitors, IEEE Standard 1036-2010, Jan. 2011.
[5] A. Greenwood, Electrical Transients in Power System. 2nd Edition. New York: Wiley, 1991, pp. 41–46.
[6] T. M. Blooming and D. J. Carnovale, “Capacitor application issues,” IEEE Transactions on Industry Applications, vol. 44, no. 4, pp. 1013–1026, Jul./Aug. 2008.
[7] T. M. Blooming, “Capacitor failure analysis,” IEEE Industry Applications Magazine, vol. 12, no. 5, pp. 38–48, Sep./Oct. 2006.
[8] H. M. Pflanz and G. N. Lester, “Control of overvoltages on energizing capacitor banks,” IEEE Transactions on Power Application Systems, vol. PAS-92, no. 3, pp. 907–915, May/Jun. 1973.
[9] D. V. Coury, C. J. dos Santos, and M.C. Tavares, “Transient analysis concerning capacitor bank switching in a distribution system,” Electric Power System Research, vol. 65, no. 1, pp. 13–21, Apr. 2003.
[10] C. Hwang, and J. N. Lou, “Transient analysis of capacitance switching for industrial power system by PSpice,” Electric Power System Research, vol. 45, no. 1, pp. 29–38, Apr. 1998.
[11] D. W. Skeans, “Recent development in capacitor switching transient reduction,” in T&D World Exposition Substation Section. New Orleans, LA, 1995, pp. 1–13.
[12] Roger C. Dugan, Mark F. McGranaghan, and H. Wayne Beaty, Electrical Power Systems Quality. Mc Graw-Hill, 1996, pp. 111–117.
[13] W.E. Reid, “Power quality issues-standards and guidelines,” IEEE Transactions on Industry Applications, vol. 32, no. 3, pp. 625–632, May/Jun. 1996.
[14] T. E. Grebe, “Power quality and the utility/customer interface,” Proc. Southcon'94 Conf., pp. 372–377, Mar. 1994.
[15] P. T. Chen, C. C. Huang, C. C. Pan, and S. Bhattacharya, “Design and implementation of a series voltage sag compensator under practical utility conditions,” IEEE Transactions on Industry Applications, vol. 39, no. 3. pp. 844–853, May/Jun. 2003.
[16] J. L. Durán-Gómez and P. N. EnjetiA, “New approach to mitigate nuisance tripping of PWM ASDs due to utility capacitor switching transients (CSTs),” IEEE Transactions on Power Electronics, vol. 17, no. 5, pp. 799–806, Sep. 2002.
[17] J. L. Durán-Gómez, P. N. Enjeti, and B. O. Woo, “Effect of voltage sags on adjustable speed drives: a critical evaluation and an approach to improve performance,” IEEE Transactions on Industry Applications, vol. 35, no. 6, pp. 1440–1449, Nov./Dec. 1999.
[18] T. E. Grebe, “Application of distribution system capacitor banks and their impact on power quality,” IEEE Transactions on Industry Applications, vol. 32, no. 3, pp. 714–719, May/Jun. 1996.
[19] M. F. McGranaghan, T. E. Grebe, G. Hensley, T. Singh, and M. Samotyj, “Impact of utility switched capacitors on customer systems. II. Adjustable-speed drive concerns,” IEEE Transactions on Power Delivery, vol. 6, no. 4, pp. 1623–1628, Oct. 1991.
[20] M. F. McGranaghan, R. M. Zavadil, G. Hensley, T. Singh, and M. Samotyj, “Impact of utility switched capacitors on customer systems-magnification at low voltage capacitors,” IEEE Transactions on Power Delivery, vol. 7, no. 2, pp. 862–868, Apr. 1992.
[21] R.A. Adams, S.W. Middlekauff, and E.H. Camm, and J.A. McGee, “Solving customer power quality problems due to voltage magnification,” IEEE Transactions on Power Delivery, vol. 13, no. 4, pp. 1335–1341, Oct. 1998.
[22] T. A. Bellei, R. P. O’Leary, and E. H. Camm, “Evaluating capacitor switching devices for preventing nuisance tripping of adjustable-speed drives due to voltage magnification,” IEEE Transactions on Power Delivery, vol. 11, no. 3, pp. 1373–1378, Jul. 1996.
[23] A. Kalyuzhny, S. Zissu, and D. Silviu, “Analytical study of voltage magnification transients due to capacitor switching,” IEEE Transactions on Power Delivery, vol. 24, no. 2, pp. 797–804, Apr. 2009.
[24] IEEE Standard for Shunt Power Capacitors, IEEE Standard 18-2002, Oct. 2002.
[25] NEMA Standards Publication CP 1-2000 (R2008), Shunt Capacitors, 2008.
[26] IEC 831-1, Shunt Power Capacitors of the Self-Healing Type for A.C. Systems Having a Rated Voltage up to and including 1000V–Part 1: General–Performance, Testing and Rating–Safety Requirements–Guide for Installation and Operation, Nov. 1996.
[27] IEEE Guide for Protection of Shunt Capacitor Banks, IEEE Standard C 37.99-2000, Jan. 2000.
[28] T. E. Grebe, “Technologies for transient voltage control during switching of transmission and distribution capacitor banks,” in Proc. IPST’95-International Conference on Power System Transients, Lisbon, pp. 189–194, Sep. 1995.
[29] J. C. Das, “Analysis and control of large-shunt-capacitor-bank switching transients,” IEEE Transactions on Industry Applications, vol. 41, no. 6, pp. 1444–1451, Nov. 2005.
[30] L. M. Smith, “A practical approach in substation capacitor bank applications to calculating, limiting, and reducing the effects of transient currents,” IEEE Transactions on Industry Applications, vol. 31, no. 4, pp. 721–724, Jul./Aug. 1995.
[31] A. A. Girgis, C. M. Fallon, J. C. P. Rubino, and R. C. Catoe, “Harmonics and transient overvoltages due to capacitor switching,” IEEE Transactions on Industry Applications, vol. 29, no. 6, pp. 1184–1188, Nov./Dec. 1993.
[32] D. J. Carnovale, “Power factor correction and harmonic resonance: a volatile mix,” EC&M Magazine, pp. 16–19, Jun. 2003.
[33] B. Bhargava, A. H. Khan, A. F. Imece, and J. DiPietro, “Effectiveness of pre-insertion inductors for mitigating remote overvoltages due to shunt capacitor energization,” IEEE Transactions on Power Delivery, vol. 8, no. 3, pp. 1226–1238, Jul. 1993.
[34] Camm E., “Shunt capacitor overvoltages and a reduction technique”, in Proc. IEEE/PES Transmission and Distribution Conference and Exposition New Orleans, LA, 180-T72, Apr. 1999.
[35] S. G. Abdulsalam and W. Xu, “Sequential phase energisation technique for capacitor switching transient reduction,” IET Generation, Transmission and Distribution, vol. 1, no. 4, pp. 596–602, Jul. 2007.
[36] R.W. Alexander, “Synchronous closing control for shunt capacitors,” IEEE Transactions on Power Application Systems, vol. PAS-104, no. 9, pp. 2619–2626, Sep. 1985.
[37] K. C. Liu and N. Chen, “Voltage-peak synchronous closing control for shunt capacitors,” IEE Proceedings – Generation, Transmission and Distribution, vol. 145, no. 3, pp. 233–238, May 1998.
[38] T. J. E. Miller, Reactive Power Control in Electric System. New York: Wiley, 1982, pp. 204–214.
[39] G. Oliver, I. Mougharbel, and G. Dobson-Mack, “Minimal transient switching of capacitors,” IEEE Transactions on Power Delivery, vol. 8, no. 4, pp. 1988–1994, Oct. 1993.
[40] J. C. Wu, H. L. Jou, K. D. Wu, and N. T. Shen, “Hybrid switch to suppress the inrush current of AC power capacitor,” IEEE Transactions on Power Delivery, vol. 20, no. 1, pp. 506–511, Jan. 2005.
[41] A. Ahmed, Power Electronics for Technology, Prentice-Hall, Inc., 1999, pp. 130–131.
[42] Ned Mohan, Tore M. Undeland, and William P. Robbins, Power Electronics: Converters, Applications, and Design. 2nd Edition, New York: John Wiley & Sons, 1995, pp. 79–113.
[43] H. J. Boening and D. A. Paice, “Fault current limiter using superconducting coil,” IEEE Transactions on Magnetics, vol. 19, no. 3, pp. 1051–1053, May 1983.
[44] H. Weinstock, Applications of Superconductivity. Kluwer Academic Publisher, 2000, pp. 451–453.
[45] T. Hoshino, K. M. Salim, A. Kawasaki, I. Muta, T. Nakamura, and M. Yamada, “Design of 6.6kV, 100A saturated DC reactor type superconducting fault current limiter,” IEEE Transactions on Applied Superconductivity, vol. 13, no. 2, pp. 2012–2015, Jun. 2003.
[46] K. M. Salim, I. Muta, T. Hoshino, T. Nakamura, and M. Yamada, “Proposal of rectifier type superconducting fault current limiter with non-inductive reactor (SFCL),” Cryogenics, vol. 44, no. 3, pp. 171–176, Feb. 2004.
[47] D. M. Dunsmore, E. R. Taylor, B. F. Wirtz, and T. L. Yanchula, “Magnification of transient voltages in multi-voltage-level, shunt-capacitor-compensated, circuits,” IEEE Transactions on Power Delivery, vol. 7, no. 2, pp. 664–669, Apr. 1992.
[48] M. T. Hagh and M. Abapour, “Nonsuperconducting fault current limiter with controlling the magnitudes of fault currents,” IEEE Transactions on Power Electronics, vol. 24, no. 3, pp. 613–619, Mar. 2009.
[49] T. Sato, M. Yamaguchi, T. Terashima, S. Fukui, J. Ogawa, H. Shimizu, and T. Sato, “Study on the effect of fault current limiter in power system with dispersed generators,” IEEE Transactions on Applied Superconductivity, vol. 17, no. 2, pp. 2331–2334, Jun. 2007.
[50] M. Yamaguchi, S. Fukui, T. Satoh, Y. Kaburaki, T. Horikawa, and T. Honjo, “Performance of DC reactor type fault current limiter using high temperature superconducting coil,” IEEE Transactions on Applied Superconductivity, vol. 9, no. 2, pp. 940–943, Jun. 1999.
[51] T. Nomura, M. Yamaguchi, S. Fukui, K. Yokoyama, T. Satoh, and K. Usui, “Single DC reactor type fault current limiter for 6.6kV power system,” IEEE Transactions on Applied Superconductivity, vol. 11, no. 1, pp. 2090–2093, Mar. 2001.
[52] K. Usui, T. Nomura, T. Satoh, M. Yamaguchi, S. Fukui, K. Yokoyama, and T. Nagasawa, “A single DC reactor type fault current limiting interrupter for three-phase power system,” IEEE Transactions on Applied Superconductivity, vol. 11, no. 1, pp. 2126–2129, Mar. 2001.
[53] IEEE Application Guide for Capacitance Current Switching for AC High-Voltage Circuit Breakers, IEEE Standard C37.012-2005, Dec. 2005.
[54] W. L. Yang, J. C. Hwang, and S. N. Yeh, “Analysis and improvement of line-capacitance effect on three-phase 161-kV bus potential transformers,” IEEE Transactions on Power Delivery, vol. 24, no. 2, pp. 837–843, Apr. 2009.
[55] F. Mekic, R. Girgis, Z. Gajic, and Ed teNyenhuis, “Power transformer characteristics and their effects on protective relays,” in Proc. 60th Annual Conf. Protective Relay Engineers, pp. 455–466, Mar. 2007.
[56] M. Steurer and K. Frohlich, “The impact of inrush currents on the mechanical stress of high voltage power transformer coils,” IEEE Transactions on Power Delivery, vol. 17, no. 1, pp.155–160, Jan. 2002.
[57] Patrick J. Colleran and E. William, “Controlled starting of AC induction motors,” IEEE Transactions on Industry Applications, vol. IA-19, no. 6, pp. 1014–1018, Nov. /Dec. 1983.
[58] J. C. Gomez and M. M. Morcos, “A simple methodology for estimating the effect of voltage sags produced by induction motor starting cycles on sensitive equipment,” in Proc. 36th IEEE IAS Annu. Meeting, Chicago, IL, vol. 2, pp. 1196–1199, Sep./Oct. 2001.
[59] G. Brauner and C. Hennerbichler, “Voltage dips and sensitivity of consumers in low voltage networks,” in Proc. CIRED, Conf. Publication 482, vol. 2, pp. 1–5, Jun. 2001.