EQUIVALENT TRANSFORMATION TECHNIQUE FOR ISLANDING DETECTION METHODS OF SYNCHRONOUS GENERATOR -REACTIVE POWER PERTURBATION METHODS USING AVR OR SVC- Jun Motohashi, Member, Takashi Ichinose, Member (Tokyo Electric Power Co.) Tadao Ishikawa, Member (CRIEPI) Chikashi Nakazawa, Member, Hiroyuki Fukai, Member, Isao Chihara, Member (Fuji Electric Co. R&D., Ltd.) Dispersed generations have been developed considering effective utilization of energy. Then a reverse power interconnection of generators is required to utilize power effectively. In Japan, "GUIDE LINE" was revised considering these situations. Then if a relay system which protects distribution systems and dispersed generators had two islanding detection methods (active and passive methods), the reverse power interconnection was made possible. Islanding detection method for synchronous generators have been developed(5)(6). However the previous methods do not take an active method into account and methods can not detect all islanding cases. Authors proposed two active islanding detection methods for synchronous generators. These two methods utilizes frequency deviation according to a active perturbation signal. This paper presents an equivalent transformation technique for the proposed two methods. Theoretical basis, analysis, practical issues and implementation of the technique are described. The proposed technique was tested using a simulation and a field test plant. T. IEE Japan, Vol. 119-B, No. 1, '99
Ktr=k2k3/(k9-k2k3k8) Ttr=k3k9Tdo'/(k9-k2k3k8) GQ=K9k3(k9k10-k2k11)/(k9-k2k3k8) Fig.1 A Linearized Synchronous Machine Model.
Table 1 Generator Constants. Fig.2 A Model System. Table 2 Linearized Machine Constants And Transfer Factors. T. IEE Japan, Vol. 119-B, No. 1, '99
Table 3 Maximum Islanding Detection Time. Table 4 Maximum Islanding Detection Time. Fig.3 Controller Block Diagrams. Fig.4 Islanding Detection Sequence. Fig.5 Open Angle of Circuit Breaker (CBO) and Detection Time.
Fig.6 Active Method Using AVR. Fig.7 Active Method Using SVC. (Detailed Transformation) Fig.8 Active Method Using SVC. (Simple Transformation) Fig.9 Line Distance and Voltage Fluctuation. Fig. 10 Field Test Plant Controller Block Diagrams, T. IEE Japan, Vol. 119-B, No. 1, '99
Fig.11 Field Test Plant. Table 5 Comparison of Field Test & Simulation results. Fig. 12 Frequency Deviation using AVR. Fig.13 Frequency Deviation using SVC. 11
(10)F.P.DEMELLO, et al., "Concepts of Synchronous Machine Stability as Affected by Excitation Control," IEEE Trans. Power Apparatus and Systems, vol.88, no.4, April 1969, pp.316-329. (11)P.M.ANDERSON and A.A.FOUAD, Power System Control and Stability, Revised Printing. New York: IEEE PRESS, 1994, p.141. (4) M.A.Redfern, et al., "Protection Against Loss of Utility Grid supply for a Dispersed Storage and Generation Unit," IEEE Trans. Power Delivery, Vol.8, no.3, July 1993, pp. 948-954. (5) M.A.Redfern, et al., "A New Microprocessor Based Islanding Protection Algorithm for Dispersed Storage and Generation Units," IEEE Trans. Power Delivery, Vol.10, no.3., July 1995, pp1249-1254. T. IEE Japan, Vol. 119-B, No. 1, '99