著者

鈴木 守

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.129, no.4, pp.495-498, 2009-04-01 (Released:2009-04-01)

被引用文献数

1 1

---

Effective Load Dispatching Automatic Controller (ELDAC) is an EMS/SCADA system for Central Load Dispatching Office in Tokyo Electric Power Company Inc. This paper introduces the progress of development of ELDAC, which forecasts demand, sets up the most efficient generation schedule, and controls total power from generators.

著者

小長谷 瑞木

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.142, no.4, pp.NL4_7, 2022-04-01 (Released:2022-04-01)

著者

兒玉 学 松前 光 木内 豪士 村上 直紀 平井 秀一郎

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.141, no.7, pp.541-546, 2021-07-01 (Released:2021-07-01)

参考文献数

18

被引用文献数

1 3

---

Three-dimensional large scale magnetohydrodynamic, two-phase flow, and electrochemical reaction coupling numerical simulations of alkaline water electrolysis with magnetic field were conducted to elucidate the bubble-bubble interaction and the influence of that on the overpotential. Numerical results shown that the magnetic field enhances the coalesce of bubbles and the bubble size was increased with the increase in the magnetic flux density. Moreover, the magnetic field suppressed the cell overpotential by suppressing the anode overpotential and ohmic overpotential. This is because, KOH concentration around the anode is increased by mixing of the electrolyte, and the reduction of the shielding effect by coalescing of the bubbles.

著者

竹原 有紗

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.131, no.5, pp.NL5_7, 2011-05-01 (Released:2011-05-01)

参考文献数

2

著者

安田 陽 米津 大吾 藤井 利昭

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.142, no.7, pp.347-359, 2022-07-01 (Released:2022-07-01)

参考文献数

23

---

Offshore wind power plants has gotten attention worldwide as one of key technology for future energy mix. Recent Japanese policy also promotes offshore wind power plants (OWPPS) on costal waters in the Sea of Japan. On the other hand, those areas are known by notorious winter lightning with upward lightning and large electric charge, that has caused catastrophic damages to onshore wind turbines in past. It is therefore needed stronger lightning risk management for offshore wind turbines than that for onshore. The authors proposed a lightning protection method using an independent lightning tower (ILT) and have stored experience by numerical calculations and small-scale model experiments. However, there still remain several uncertainties in the given data. This paper proposes a new method on CBA (cost-benefit analysis) regarding with the uncertainty. In the concrete, a probability density function, e.g. Gauss Function, is superimposed on quasi-quantitative data with several uncertainty given by experiment tests, which enable optimization of net benefit and objective and quantitative decision making for appropriate risk management even under uncertainty.

著者

横山 茂

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.124, no.2, pp.177-180, 2004 (Released:2004-05-01)

参考文献数

7

被引用文献数

17 23

---

The protection of wind turbine blades from lightning damages is increasingly important for an increase of wind power generation. This paper shows the manner of lightning damage of wind turbine blades and the difference between the blades made of various materials. Possible protection measures from lightning damages are shown for various types of wind turbine blades. Moreover we stress that protection of wind turbine blades from winter lightning damages is necessary for us to build wind power generators at the coast faced to the Sea of Japan.

著者

堤 泰行 山口 雅教

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.7, pp.776-784, 1993-07-20 (Released:2008-12-19)

参考文献数

3

---

Experimental studies and analytic theories are presented on a steam share between exhausted air and exhausted fuel from phosphoric acid fuel cells.The steam share depends on a fiow rate of air and fuel. The share characteristics can be explained by a steam transport mechanism in which steam carried with air and fuel are combined with steam permeated through an electrolyte layer.The mechanism is applied to the published analytic theory for fuel cell performance. The revised theory can calculate steam share between air and fuel at each part of a cell. The calculated steam share between exhausted air and exhausted fuel at typical operating conditions of a fuel cell plant is presented.A simplified method for calculating steam share is developed and shown to give almost the same results with the detailed theory for fuel cell performance.

著者

西崎 康 入江 寛 横山 明彦 多田 泰之

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.129, no.1, pp.50-56, 2009-01-01 (Released:2009-01-01)

参考文献数

12

被引用文献数

15 26

---

Considering interconnection of a large-capacity of wind power generation to the utility grid, it is of great concern that its output power fluctuation has adverse influences, e.g. frequency fluctuation. There have so far been some research works on installation of battery energy storage systems (BESS), as a solution of these problems. However, owing to very high cost of the BESS, its capacity should be as small as possible. In this paper, not only the installation of the BESS as one of measures of suppressing the frequency fluctuation caused by wind power generation, but also blade pitch angle control for blunting the output power of wind turbine generators (WTGs) is also considered. This paper proposes a coordinated control method of the BESS and the blade pitch angle, and evaluates reduction of the capacity of the BESS and the power generation loss caused by blunting the output power which should be originally generated by WTGs.

著者

鈴木 郁海 根岸 信太郎 池上 貴志

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.140, no.6, pp.521-530, 2020-06-01 (Released:2020-06-01)

参考文献数

18

---

It is expected to promote the introduction of renewable energy (RE), such as photovoltaic (PV) and wind power (WP), from the view points of carbon dioxide reduction and diversification of energy sources. However, as the introduction of RE into the conventional power grid, output curtailment of RE will increase due to supply and demand balance constraints. In this study, we have developed a model and data which enable long-term power supply and demand analysis based on some scenarios. Using this model and data, we analyzed the transition of the amount of RE generation and the amount of RE curtailment per installed capacity. As a result, the change in the facility utilization rate of PV and WP is clarified quantitatively based on the influence of RE curtailment. The amount of PV curtailment was significantly increased in Kyushu and Tohoku area, where RE is particularly widespread. The results of this paper can be used to evaluate how and when it is necessary to take measures such as the introduction of storage batteries.

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.140, no.12, pp.NL12_1, 2020

著者

原田 信弘 佐々木 徹 藤野 貴康

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.135, no.8, pp.NL8_5, 2015-08-01 (Released:2015-08-01)

著者

根岸 信太郎 池上 貴志

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.12, pp.757-766, 2019-12-01 (Released:2019-12-01)

参考文献数

20

被引用文献数

6

---

In this paper, a new method of water pumping scheduling in a water distribution system with providing balancing reserves to power systems is proposed. This method enables to obtain a daily schedule of pumping water and balancing reserves, which is based on prices of electric energy and balancing reserves, hourly water demand profile, and properties between water flow quantity and consumption electricity of water pumps. The proposed method consists of an optimization model which is formulated by Mixed Integer Linear Programming (MILP). The constraints about the fluctuation of the volume of water in a reservoir, which is occurred by providing the balancing reserves, is added into the proposed model. Adding these constraints, stable water distribution is enabled even when the balancing reserves are activated. To verify the validity of the proposed method, simulations of water pumping scheduling in some cases were done. As a result, net operational cost was decreased when water pumps provided the balancing reserves. Moreover, the operational feasibility of providing the balancing reserve from water pumps is clarified.

著者

乾 昭文 小林 恒夫 寺西 常治 池田 正己

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.118, no.5, pp.563-572, 1998-05-01 (Released:2008-12-19)

参考文献数

21

---

In this paper, the static electrification phenomena on the dielectric materials by SF6 gas flow were investigated. When pure SF6 gas flows on the dielectric materials at high speed up to 25m/sec, no electrification was observed on the dielectric material surfaces. In case of the flow contained dielectric microscopic particles colliding with dielectric materials, it is confirmed that the SF6 gas flow of speeds above 5m/sec causes the electrification on the dielectric surfaces. The faster the SF6 gas flow, the higher the surface potential of the dielectric material is. Such phenomena of static electrification of SF6 gas contaminated with microscopic dielectric particles were explained to be caused by the friction between the dielectric materials and the dielectric microscopic particles in SF6. The polarity and the magnitude of the surface potential of the material, after flowing the SF6 gas contaminated with dielectric particles, are confirmed by the result of a general friction experiment of the two dielectric materials. It is considered that a well-controlled gas insulated transformer not contaminated with microscopic dielectric particles in SF6 can not generate electrification phenomena.

著者

高木 雅昭 原 亮一 佐藤 敏之 大山 力

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.12, pp.1177-1186, 2005 (Released:2006-03-01)

参考文献数

15

---

It is very effective to enhance the robustness of control over the faults occurred in power system in order to realize stable and reliable power supply. The sliding mode control based on the Variable Structure System (VSS) theory is paid attentions as one of the promising robust control scheme. In the sliding mode control, the structure of the control system is changed across the hyper plane (switching plane) in state space so that the state variables of the system are kept on the hyper plane.This paper proposes a novel control method of generator's excitation system in which the concept of sliding mode control is employed. More specifically, the proposed method switches the reference voltage used in AVR according to the sign of switching function. This paper also discusses the systematic design procedure of the optimal hyper plane. Performance and effectiveness of the proposed control method are investigated through both numerical studies and experimental tests using the single-machine infinite-bus system simulator. Both results show that the proposed control method can damp the transient swing caused by a fault effectively.

著者

島 義和 高橋 理音 村田 年昭 田村 淳二 戸巻 雄一 富永 忍 坂原 淳史

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.9, pp.855-864, 2005 (Released:2005-12-01)

参考文献数

14

被引用文献数

3 3

---

Recently, wind power generation is increasing in the world. In the wind power stations, induction machines are mostly used as generators. Since induction generators have a stability problem similar to the transient stability of synchronous machines, it is important to analyze the transient stability of power systems including wind generators. Although there have been some reports analyzing the transient stability problem, wind turbine and wind generator are, in most cases, modeled as one mass shaft system having total inertia constant. This paper presents simulation analyses of transient stability of power system including induction generator which is expressed by a two-mass shaft model and analyzes an effect of shaft system modeling on the transient stability characteristics. Simulations are performed by PSCAD/EMTDC in this study.

著者

本田 公韶 佐々木 博司 長田 稔 真恵原 悟 横瀬 宏

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.115, no.12, pp.1432-1437, 1995-11-20 (Released:2008-12-19)

参考文献数

4

---

The demand-supply imbalance on electric power system is absorbed by system frequency variations, before the LFC controls. Since frequency fluctuations are common in all linked blocks, demand-supply imbalance of one block is absorbed by another block too. Demand-supply imbalance arises in another block simultaneously, and is absorbed by the former block. These mutual supports have a direct effect on linkage power fluctuations. The size of this self-regulation is regarded as proportional to the size of frequency fluctuation and the ratio of the former to the latter is nearly proportional to the block capacity. But, at a short period variation range, there is a fear that such a proportional relation will be biased by linkage position. We analyze this point, and reached the following conclusions. First, we can prove the existence of self-regulation bias theoretically and point out that the bias has some effect on linkage power fluctuations at short period variation range. Second, we apply this analytical method to 4 blocks-linked system of Japan, and compare the theoretical value with measured one. The result indicates no correlation among demand fluctuations of those blocks which are presupposed for calculation of the theoretical values; among several blocks is found some ununiformity of the smallest unit size of demand power variations.

著者

福井 千尋

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.134, no.5, pp.NL5_6, 2014 (Released:2014-05-01)

著者

田辺 茂 小林 淳男

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.117, no.7, pp.1024-1031, 1997-06-20 (Released:2008-12-19)

参考文献数

10

---

We have been developing thyristor valves for high-voltage dc transmission systems for more than 20 years. During this period, the size, power loss and reliability are dramatically improved and one of the technical advancements which support the improvements is to increase the voltage and current rating of thyristors. However when thyristor voltage rating becomes higher than 6kV, increasing the voltage rating does not lead size and power loss reduction of the valve because of turn-off characteristic deteriorations. This paper describes the method which can optimize the thyristor characteristics in such a way that the size and power loss of valves are minimized. Two different approaches for HVDC and back-to-back systems are presented.

著者

白井 五郎 沓掛 政志 竹内 茂

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.113, no.12, pp.1371-1380, 1993-12-20 (Released:2008-12-19)

参考文献数

21

---

This paper describes a unified automatic generation control (AGC) scheme coordinating EDC (Economical Load Dispatching Control) and LFC (Load Frequency Control). So far, in absorption of the load fluctuations occurring on power systems, both of EDC and LFC systems have been considered separately each other. By coordinating both control systems, undesirable system behaviours are avoided. The responses of frequency deviation, turbine power fluctuation and tie-line power flow deviation are smoothed using the proposed AGC scheme.The background theory is based on servo-type optimal control theory. The structure of the proposed control method is a decentralized type. So, the implementation in multi-area power systems is easy.The effectiveness of the proposed unified AGC is illustrate_??_ by an example, and the simulation results on three-area power systems show that the method is encouraging. In this paper, some of the problems associated with the application of this method to the multi-area AGC are discussed.

著者

Yasunobu Yoshida Shigekazu Katagiri Masato Kawaguchi

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.123, no.5, pp.602-607, 2003 (Released:2004-03-31)

参考文献数

7

被引用文献数

1 1

---

This paper describes the temperature rise and the thermal stability of tank type power capacitors and a analyzing method of the stability and permissible overload factor using a computer. When capacitor is operated at high ambient temperature and under excessive high voltage, the temperature of the dielectric rises higher and in some cases the capacitor looses the thermal balance and finally breakdowns thermally.We measured the heat radiation coefficient and temperature rise of the capacitor, and clarified that the radiated heat calculated from the heat radiation coefficient and the area of the tank coincided with the generated heat calculated from the output of the capacitor and the loss factor of the dielectric. Furthermore we developed analyzing method of thermal stability and permissible overload factor of capacitors using a computer. By this analysis it becomes possible to know the permissible overload factor and the temperature of the capacitor dielectric without performing the temperature rise test which requires long time and much cost.