著者

兌 瀟偉 伊藤 雅一 藤本 悠 林 泰弘 朱 桂萍 姚 良忠

出版者

一般社団法人 電気学会

雑誌

電気学会論文誌B(電力・エネルギー部門誌) (ISSN:03854213)

巻号頁・発行日

vol.139, no.3, pp.212-224, 2019-03-01 (Released:2019-03-01)

参考文献数

34

被引用文献数

3

---

With the increase of wind power penetration in power system, the uncertainty caused by wind farm forecast error is enlarged which results in deterioration of wind power curtailment. In order to optimize the capacity of battery storage for mitigating forecast error, firstly it is necessary to improve the accuracy of forecast error model. This paper proposed a modeling method of forecast error time series in usage of beta distribution. Varying with forecast output, parameters of the beta distribution are estimated by maximum likelihood estimation. Autocorrelated forecast error obeying beta distribution is generated by correlated Monto-Carlo simulation. Based on the forecast error model, an optimization method is proposed to determine the optimum size of battery storage for mitigating forecast error. Through maximizing the total profit composed of electricity sales revenue, penalty and battery cost, the optimum size of battery storage is calculated. The results show that the forecast error model proposed in this paper is able to simulate both probability density function and autocorrelation correctly, which is beneficial to improving the accuracy and economy of battery storage sizing.

著者

Sarjiya Eua-arporn Bundhit Yokoyama Akihiko

出版者

一般社団法人 電気学会

雑誌

電気学会論文誌. B, 電力・エネルギー部門誌 = The transactions of the Institute of Electrical Engineers of Japan. B, A publication of Power and Energy Society (ISSN:03854213)

巻号頁・発行日

vol.127, no.11, pp.1159-1167, 2007-11-01

参考文献数

25

被引用文献数

1 5

---

One of the common problems faced by many electric utilities concernes with the uncertainty from both load forecast error and generating unit unavailability. This uncertainty might lead to uneconomic operation if it is not managed properly in the planning stage. Utilities may have many operational tools, e.g. unit commitment, economic dispatch. However, they require a proper operating strategy, taking into account uncertainties. This paper explicitly demonstrates how to include the uncertainties to obtain the best operating strategy for any power systems. The uncertainty of the load forecast is handled using decision analysis method, meanwhile the uncertainty of the generating unit is approached by inclusion of risk cost to the total cost. In addition, three spinning reserve strategies based on deterministic criteria are incorporated in the development of scenario. Meanwhile, Mixed Integer Linear Programming method is utilized to generate unit commitment decision in each created scenario. The best strategy which gives the minimum total cost is selected among the developed scenarios. The proposed method has been tested using a modified of IEEE 24-bus system. Sensitivity analysis with respect to the number of unit, expected unserved energy price, standard deviation of load forecast, and probability of load level is reported.

著者

曽根 悟 阿部 茂

出版者

The Institute of Electrical Engineers of Japan

雑誌

電気学会論文誌. B (ISSN:03854213)

巻号頁・発行日

vol.92, no.3, pp.195-204, 1972-03-20 (Released:2008-12-19)

参考文献数

6

著者

匹田 政幸

出版者

The Institute of Electrical Engineers of Japan

雑誌

電気学会論文誌B(電力・エネルギー部門誌) (ISSN:03854213)

巻号頁・発行日

vol.122, no.4, pp.482-485, 2002-04-01 (Released:2008-12-19)

参考文献数

42

---

This article deals with trend of sensing, monitoring, diagnostics and maintenance technology in electric power apparatus, especially, gas insulated switchgear (GIS). Partial discharge measurement is one of key technology and the most promising method for developing highly reliable diagnostics for insulation performance of the high voltage apparatus. The review is made by focusing UHF sensors and acoustic method for detecting electromagnetic and ultrasonic waves caused by partial discharges in GIS, respectively.

著者

宮嵜 悟

出版者

一般社団法人 電気学会

雑誌

電気学会論文誌B(電力・エネルギー部門誌) (ISSN:03854213)

巻号頁・発行日

vol.138, no.12, pp.NL12_8, 2018-12-01 (Released:2018-12-01)

著者

藤林 宏一 村崎 憲雄 松井 満

出版者

The Institute of Electrical Engineers of Japan

雑誌

電気学会論文誌. B (ISSN:03854213)

巻号頁・発行日

vol.105, no.10, pp.867-872, 1985-10-20 (Released:2008-12-19)

参考文献数

6

著者

鈴木 守 石井 隆裕 神尾 光一 鈴木 浩 伊庭 健二

出版者

The Institute of Electrical Engineers of Japan

雑誌

電気学会論文誌B(電力・エネルギー部門誌) (ISSN:03854213)

巻号頁・発行日

vol.112, no.10, pp.937-944, 1992-10-20 (Released:2008-12-19)

参考文献数

9

被引用文献数

3

---

The idea of unbalanced load flow calculation was proposed many years ago. At that time, however, the needs for such techniques was not an urgent one. Modern power system networks are comprised of long untransposed transmission lines. Therefore, for some kinds of analysis, it is now almost impossible to treat a system as though it were a symmetrical network. The aims of most previous studies were oriented to solve voltage/current imbalance in local or small systems, as local imbalance was a serious concern. This is still an important issue, but more recently our needs have become concentrated on practical bulk power systems, since principal EHV lines are entirely untransposed. In this paper, the development of practical unbalanced load program and practical experience with it are reported. This program was developed for steady state analysis of large-scale practical networks under many possible unbalanced condition. The Newton-Raphson method in polar coordinates is used, since fast and moderate convergent characteristics are suitable for solving solutions. The program was applied to practical case studies. The models contain all of the 500 kV and most of the 275 kV overhead transmission lines in TEPCO. Since the density of the Jacobian matrix is higher than in single phase load flows, the number of non zero elements is extremely large. Convergent characteristics are excellent in all cases. The fear of numerical instability has been allayed.

著者

林 重雄 川田 明 長澤 隆士 横山 尚登

出版者

The Institute of Electrical Engineers of Japan

雑誌

電気学会論文誌B(電力・エネルギー部門誌) (ISSN:03854213)

巻号頁・発行日

vol.112, no.11, pp.969-976, 1992-11-20 (Released:2008-12-19)

参考文献数

8

被引用文献数

1 3

---

The paper demonstrates that normal power system operating data may be used to determine the power-frequency characteristics in power system. Data are processed as random signals using spectral analysis techniques and the results estimate the generator and load power-frequency characteristics as transfer functions. The generator characteristics Kg is determined as a transfer function of the system in which input signals are frequency fluctuation ΔF and generator power setting signal ΔPg and output signal is generator power output ΔPe. For estimating the load characteristics Kl, there is a difficulty. There is a relation of ΔPl=ΔLo+KlΔF, between actual load ΔPl, ideal load under the state of nominal frequency ΔLo and fluctuation of system frequency ΔF. While, because it is impossible to measure ΔLo directly, ΔLo and KlΔF can not be separated. As to a partial system, when its capacity is small enough compared with the total system capacity, the contribution of ΔLo in a partial system to ΔF of the total system may be ignored, that is, ΔF and ΔLo are considered as independent phenomena. So, the cross-spectrum of ΔF and ΔLo decreases to zero according to the increase of data in number and Kl of the partial system can be estimated.

著者

大城 諒士 塩塚 大志 原田 繁実 金子 英治 井上 喜乃 倉田 智成 横倉 邦夫

出版者

一般社団法人 電気学会

雑誌

電気学会論文誌E(センサ・マイクロマシン部門誌) (ISSN:03854213)

巻号頁・発行日

vol.138, no.9, pp.791-798, 2018

被引用文献数

2

---

<p>Surge voltages often have much higher value and changing rate than those of power frequency voltages, and might cause damages to apparatuses or equipment not only on near a surge source, for example lightning struck point, but also on far points from it due to propagating. In addition, surge phenomena often become complex due to the reflections and the superpositions on a point where surge impedances having different value are connected. The surge phenomenon occurring on a power cables connected with a transmission tower is one of these cases. This research's goal is to propose the EMTP model for surge phenomenon occurring on cables arranged through a transmission tower. The proposed model simulates such cable by using a cable model through a pipe conductor. The results calculated by the proposed model ware compared with the results by VSTLrev (Virtual Surge Test Lab. Restructured and Extended Version) which is a surge analysis program based on FDTD (Finite Difference Time Domain) method to verify the accuracy of the proposed model. As a result, the proposed model is reasonable for analysis of a surge phenomenon occurring on a cable through a transmission tower.</p>

著者

東盛 良夫

出版者

一般社団法人 電気学会

雑誌

電気学会論文誌. B (ISSN:03854213)

巻号頁・発行日

vol.113, no.2, pp.177-184, 1993

被引用文献数

1

---

Electric power is in great demand, and it is transmitted to distant places for consumers with high efficiency, where various insulators are being used for power transmission and distribution line for insulation.<br>Insulators contaminated by salt particles have been causes for flashovers on the surface under high voltage in humid climate and light rain. Rapid salt contamination of the insulator surface by typhoons has been investigated on the campus of University of the Ryukyus for several years.<br>The results obtained from the exposure tests are:<br>(1) Accumulative contamination of the insulator surface occurred always on the bottom surface of the insulators, and on the upper surface of insulators during the period without rainfall.<br>(2) The extent of contamination of the pin-type insulators with the saltproof dishes was 1/2_??_1/6 in comparison to that of pin-type insulators without ones.<br>(3) The salt contamination of the insulator surfaces is almost always influenced by wind speed and precipitation.<br>(4) Flashover voltage of salt contminated insulators by typhoons drops to approximately 1/10 of that for clean and dry insulators.

著者

斎藤 浩海

出版者

The Institute of Electrical Engineers of Japan

雑誌

電気学会論文誌B(電力・エネルギー部門誌) (ISSN:03854213)

巻号頁・発行日

vol.119, no.8-9, pp.897-900, 1999-08-01 (Released:2008-12-19)

参考文献数

28

被引用文献数

1 1

著者

林 重雄 米田 孝史 川田 明 長沢 隆士 森田 恵

出版者

The Institute of Electrical Engineers of Japan

雑誌

電気学会論文誌B(電力・エネルギー部門誌) (ISSN:03854213)

巻号頁・発行日

vol.113, no.11, pp.1231-1238, 1993-11-20 (Released:2008-12-19)

参考文献数

12

被引用文献数

1 1

---

It is important to include the behavior of load in studies of loss of generation and consequent load shedding and also in studies of long-term dynamics of a power system. This paper proposes a method which estimates load-frequency and load-voltage characteristic constants separately at the same time, by using normal operating data.The power system can be represented as an equivalent model which is composed of a major bus load, an equivalent impedance and a voltage source behind it. When the load capacity is small enough compared with the total system capacity, variations of active power of the load have little effect on frequency changes in the total system. Voltage changes behind the equivalent impedance are caused by variations of the operating condition in the external system, so voltage changes are independent to variations of active and reactive power of the major bus load under the state of nominal frequency and voltage. So coherences between them decreases to zero according to the increase of data in number and it is possible to estimate the load-frequency and load-voltage characteristic constants. Necessary measuring periods and accuracies of estimation are clarified and the effectiveness of the proposed method is verified by simulation results.

著者

中村 政俊 籏崎 裕章

出版者

The Institute of Electrical Engineers of Japan

雑誌

電気学会論文誌. B (ISSN:03854213)

巻号頁・発行日

vol.97, no.7, pp.397-404, 1977-07-20 (Released:2008-12-19)

参考文献数

8

著者

西川 尚男 菅原 俊一 栗原 塁 青木 努 小上 泰司

出版者

一般社団法人 電気学会

雑誌

電気学会論文誌B(電力・エネルギー部門誌) (ISSN:03854213)

巻号頁・発行日

vol.125, no.7, pp.680-686, 2005 (Released:2005-10-01)

参考文献数

20

被引用文献数

4 3

---

It is well known that the operation with low humidified reactants accelerates cell voltage loss of PEFC. On the other hand, the mechanism of the voltage loss is not clear. On this study, two kinds of cells which have different thickness membrane (15 and 30μm) were evaluated under operation with low humidified reactants to clarify the voltage loss mode. The study indicates that there are two different cell voltage loss modes. For 15μm cell (a thin membrane cell), the cell voltage decayed along with open circuit voltage decrease with H2 crossover increase. It is the case that H2 crossover depresses cell voltage. For 30μm cell (a thick membrane cell), the cell voltage decayed along with open circuit voltage decrease without H2 crossover increase. This decay mechanism of voltage loss without H2 crossover was focused to study. New methods for measuring humidity distribution and current distribution in a cell were introduced for further analyze. It is found that effective catalyst area loss in cathode catalyst layer could depress cell voltage.

著者

高木 雅昭 岩船 由美子 山本 博巳 山地 憲治 岡野 邦彦 日渡 良爾 池谷 知彦

出版者

一般社団法人 電気学会

雑誌

電気学会論文誌. B, 電力・エネルギー部門誌 = The transactions of the Institute of Electrical Engineers of Japan. B, A publication of Power and Energy Society (ISSN:03854213)

巻号頁・発行日

vol.130, no.7, pp.651-660, 2010-07-01

参考文献数

19

被引用文献数

3 1

---

In the power sector, the national government has set the goal that the introduction of PV reaches 53 million kW by 2030. However, large-scale introduction of PV will cause several problems in power systems such as surplus electricity. We need large capacity of pumped storages or batteries for the surplus electricity, but the construction costs of these plants are very high. On the other hand, in the transport sector, Electric Vehicle (EV) is being developed as an environmentally friendly vehicle. To promote the diffusion of EV, it is necessary to build infrastructures that can charge EV in a short time; a battery switch station is one of the solutions to this problem. At a station, the automated switch platform will replace the depleted battery with a fully-charged battery. The depleted battery is placed in a storage room and recharged to be available to other drivers. In this study, we propose the use of station's battery as a countermeasure for surplus electricity of PV and evaluate the economic value of the proposed system. We assumed that 53 million kW of PV is introduced in the nationwide power system and considered two countermeasures for surplus electricity: (1) Pumped storage; (2) Battery of station. The difference in total annual cost between Pumped case and Battery case results in 792.6 billion yen. Hence, if a utility leases the batteries from stations fewer than 792.6 billion yen, the utility will have the cost advantage in Battery case.

著者

一ノ瀬 貴士 浅見 隆 木村 隆幸

出版者

The Institute of Electrical Engineers of Japan

雑誌

電気学会論文誌B(電力・エネルギー部門誌) (ISSN:03854213)

巻号頁・発行日

vol.114, no.7-8, pp.715-722, 1994-07-20 (Released:2008-12-19)

参考文献数

2

被引用文献数

1 2

---

When a grid fails to be supplied with electric power, a photovoltaic generation system connected to the grid may possibly start islanding. Therefore, the photovoltaic generation system needs to have a protective equipment for detecting not only fault of the grid and the system but also islanding of the system. This paper describes the protective equipment that prevents the photovoltaic generation system connected to the grid from starting islanding. It does so by detecting (1) a periodical frequency variation of voltage caused at the connection by output of a reactive power variation of a photovoltaic inverter and (2) a rapid change of harmonic voltage caused by exciting characteristics of a pole transformer.

著者

垣本 直人 林 文杉 林 宗明

出版者

The Institute of Electrical Engineers of Japan

雑誌

電気学会論文誌B(電力・エネルギー部門誌) (ISSN:03854213)

巻号頁・発行日

vol.110, no.6, pp.495-503, 1990-06-20 (Released:2008-12-19)

参考文献数

8

---

In this paper, an expert system was developed for initial stage restoration of EHV power system from system blackout. The operations to be done in case of blackout, are usually determined at every electric station by operation rules, and the power system is restored to the prefault state by carrying out the determined operations at each electric station. In case a regular operation should not work well, several supplementary operations are prepared. This method has some merits that it can restore along normal operation state, that its logic is simple, etc. Because of these merits, a part of the operation rules have been automated by automatic restoration equipments, but in case of system blackout, such human judgements as to secure initial power source are required, and operations by commands from a load-dispatching office become dominant. In this paper, an outline of restoration process was firstly clarified through analysis of the operation rules. Next, the operation rules were transformed into production rules, and were put in order at every electric station. An individual knowledge base was prepared for each group of electric stations in construction of the expert system, and a proper order was introduced in choosing a station to be restored, by which vain search of rules was eliminated. The expert system was applied to a model power system, and it was shown that the computation time for generating all restoration operations is about 0.5s, and that the system can deal with cases where there are some damaged equipments.

著者

佐々木 鉄於 小山 泰史

出版者

The Institute of Electrical Engineers of Japan

雑誌

電気学会論文誌B(電力・エネルギー部門誌) (ISSN:03854213)

巻号頁・発行日

vol.121, no.4, pp.559-569, 2001-04-01 (Released:2008-12-19)

参考文献数

4

---

We study the voltage stiffness effect for cascading tripping and its protection in power systems. This paper describes a new selective method of proper system separating point to prevent from system failure extension to wide area. We define “the voltage stiffness” by short circuit capacity and line impedance, and explain an operation to select proper separation point. In addition, we consider the security after system separations. It is dominated by both increase of reactive power transmission losses and margin of reactive power supply of generator. The basic 4 power system structures are also considered in this paper. The topological analysis of power system can show the best system structure in both power interchange and cascading trip protection. We apply the proposed method to practical power systems and simulate power system faults. Simulation results show that separating system at the selected point can defend cascading tripping.

著者

荒木 智勇 林 孜 黒柳 行央

出版者

一般社団法人 電気学会

雑誌

電気学会論文誌. B (ISSN:03854213)

巻号頁・発行日

vol.110, no.7, pp.591-597, 1990

---

We have been developing GILs for use as large capacity transmission lines since 1969. In 1979, GIL was applied to a 154kV in-yard link line of The Tokyo Electric Power Co., Inc. for the first time in Japan. In 1980, we began the development of a compact GIL to improve cost efficiency and applicability, it was applied to a 500kV incoming line of The Tokyo Electric Power Co., Inc. in 1985. This project planned as 275kV getaway lines connected to overhead line (810mm²&times;4) in Shin Noda Substation of The Tokyo Electric Co., Inc. The 8, 000A class 275kV GILs are the largest current underground transmission lines in the world. The paper describes the design, installation and tests of the project.

著者

六戸 敏昭 八木橋 義豊 遠藤 奎将 青柳 健二 斉藤 仁 大森 荘司

出版者

一般社団法人 電気学会

雑誌

電気学会論文誌. B, 電力・エネルギー部門誌 = The transactions of the Institute of Electrical Engineers of Japan. B, A publication of Power and Energy Society (ISSN:03854213)

巻号頁・発行日

vol.125, no.12, pp.1270-1277, 2005-12-01

参考文献数

15

被引用文献数

13 7

---

SF₆ gas has excellent dielectric strength and interruption performance. For these reasons, it has been widely used for gas insulated switchgear (GIS). However, use of SF₆ gas has become regulated under agreements set at the 1997 COP3. So investigation and development for GIS with a lower amount of SF₆ gas are being carried out worldwide. Presently, SF₆ gas-free GIS has been commercialized for the 24kV class. Air or N₂ gas is used as insulation gas for this GIS. On the other hand, SF₆ gas-free GIS has not been commercialized for 72kV class GIS. Dielectric strengths of air and N₂ gas are approximately 1/3 that of SF₆ gas. So to enhance insulation performance of air and N₂, we have investigated a hybrid gas insulation system which has the combined features of providing an insulation coating and suitable insulation gas. We have developed the world's first 72kV SF₆ gas-free GIS.<br>This paper deals with key technologies for SF₆ gas-free GIS such as the hybrid insulation structure, bellows for the high pressure vacuum circuit breaker, a newly designed disconnector and spacer and prevention of particle levitation. Test results of 72kV high pressure air-insulated GIS with the vacuum circuit breaker are described.