著者

田中 学 泉 裕一朗 奥野 喜裕

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.136, no.2, pp.205-210, 2016-02-01 (Released:2016-02-01)

参考文献数

22

---

MHD (magnetohydrodynamic) electrical power generation experiments have been conducted with a seed-free high temperature inert gas plasma in a disk-shaped Hall-type generator driven by a single-pulsed shock tunnel. Xenon is used as a working gas to archive a high performance at a low inlet total temperature, where the total gas temperature is varied in the range of 4600-10000K at the generator inlet. An enthalpy extraction ratio of 4.8% is obtained at the inlet total temperature of 7000K, and this value is much higher than that for argon at the same inlet total temperature. The unstable and non-uniform plasma attributed to ionization instability is observed at a high magnetic flux density and a high load resistance.

著者

田中 学 奥野 喜裕

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.527-532, 2015-08-01 (Released:2015-08-01)

参考文献数

22

被引用文献数

5 3

---

R-θ two dimensional numerical simulations have been carried out to clarify the plasma behavior in a high-temperature inert gas plasma disk-shaped MHD generator. At low inlet total temperature and high load resistance, the plasma has spiral structure which is similar to the non-uniform structure under the weak noble gas ionization condition in a seed-plasma MHD generator. As seen in a linear-shaped faraday-type MHD generator, the plasma becomes stable with increase in the inlet total temperature because the coulomb collision of electrons becomes dominant. Even at low inlet total temperature, the ionization instability can be suppressed for low load resistance, because the relatively low electron temperature due to less Joule heating makes the ionization relaxation time longer than plasma residential time.

著者

小松 文彦 田中 学 村上 朝之 奥野 喜裕

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.7, pp.620-625, 2014 (Released:2014-07-01)

参考文献数

9

被引用文献数

5 5

---

High temperature inert gas (argon) plasma MHD electrical power generation using a linear shaped channel with Hall and diagonal connections has been conducted. It is revealed from the observation by using a high-speed camera that the MHD power-generating plasma is almost stable regardless of the connection type. Enthalpy extraction ratios of 5.6% for the Hall connection, 6.7% for the diagonal connection (diagonal angle 53∼66 degree), and 10.1% for the diagonal connection (diagonal angle 36∼48 degree) have been achieved under the operating conditions of an inlet total temperature of 9000K, an inlet total pressure of 0.105MPa, and a magnetic flux density of 4.0T. The output power can suffer from a low electric field in the upstream region in a Hall connection, and is improved for no Hall current condition in a diagonal connection.

著者

田中 学 村上 朝之 奥野 喜裕

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.7, pp.614-619, 2014 (Released:2014-07-01)

参考文献数

13

---

MHD power generation experiments have been conducted by using a single-pulsed shock-tunnel facility, where the high temperature inert gas (pure argon) at a fixed total temperature of 9000K is introduced into a linear shaped Faraday type generator without any seeding. The fluctuations in the output power and the light emission from the plasma are found to be small, and the pure inert gas plasma seems to be rather stable free from the ionization instability. The output power is improved with increasing the magnetic flux density in almost quadric way and the enthalpy extraction ratio does not depend on the inlet total pressure (11.2%-12.9% for 0.063MPa-0.105MPa). The generator performance obtained here is surely competitive or superior to that of conventional seed plasma MHD generators in the past.

著者

田中 学 村上 朝之 奥野 喜裕

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.464-469, 2014 (Released:2014-05-01)

参考文献数

16

被引用文献数

3 3

---

The plasma fluid flow behavior and power generation characteristics in a Faraday-type magnetohydrodynamics (MHD) generator using high temperature inert gas (argon) plasma has been examined by a time-dependent two-dimensional numerical simulation. The inhomogeneous and unstable plasma at an inlet total temperature of 7000K results in the reduction and fluctuation of the output power. The plasma changes to homogeneous and stable one with the increase in the inlet total temperature to 9000K. One of the reasons of the suppression of the ionization instability can be due to the weakness of the dependency of the electrical conductivity on the electron number density because the coulomb collision of electrons becomes dominant under the departure from Saha equilibrium.

著者

森本 慎一郎 朴 炳植 劉 薇 小杉 隆信

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.11, pp.1307-1316, 2004 (Released:2005-02-01)

参考文献数

24

---

For the purpose of mitigating carbon dioxide emissions, three renewable energy transportation systems are proposed in which methanol is synthesized by use of wind power generation energy at an oversea and is transported to Japan to be used for a power generation. The proposed systems are the following three systems: (1) wind energy and captured CO2 utilization system, (2) wind energy and coal utilization system, and (3) wind energy and biomass utilization system. The characteristic and cost of the proposed systems’ components such as a wind power generation and a methanol synthesis plants are investigated, and so are the energy and carbon flows of the systems, assuming that the wind power generation plant is constructed at the eastern coast of Russia. Major indicators such as energy efficiency, methanol cost, CO2 reduction cost, etc., of the proposed systems are evaluated together with those of a similar CO2 recycling system utilizing hydraulic power. On the basis of the evaluation results, the wind energy and biomass utilization system is shown to be the most excellent among the evaluated systems from the viewpoints of the CO2 reduction cost. When LNG cost is increased, its estimated CO2 reduction cost islower than that of a CO2 recovery system adopted to a conventional LNG-fired power plant. Consequently, the proposed system is expected to be a feasible option for CO2 reduction in the near future when the wind power generation cost is much decreased.

著者

大槻 貴司 尾羽 秀晃 川上 恭章 下郡 けい 水野 有智 森本 壮一 松尾 雄司

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.142, no.7, pp.334-346, 2022-07-01 (Released:2022-07-01)

参考文献数

53

被引用文献数

2

---

This study investigated cost-effective energy mix for realizing net zero CO2 emissions in Japan by 2050, employing an energy system optimization model with hourly electricity balances. The detailed temporal resolution enables the model to capture intermittency of variable renewable energy (VRE) and costs of system integration measures. Siting constraints on VRE, such as prohibiting solar PV and onshore wind developments in forest and offshore wind developments inside fishery rights area, are incorporated in the model to reflect the environmental protection and social acceptance perspectives. Simulation results imply that a well-balanced power generation mix, combining renewables, nuclear, gas-fired with carbon capture and storage, as well as ammonia-fired, would contribute to curbing mitigation costs. In contrast, a simulation case with very high VRE penetration poses economic challenges. Average shadow price of electricity in 2050 in a 100% renewables case (RE100) is projected to be more than doubled from a reference case which is based on middle-of-the-road assumptions. Marginal CO2 abatement cost in 2050 increases from 49,200 JPY/tCO2 in the reference case to 75,300 JPY/tCO2 in the RE100 case. The economic viability of high VRE penetration is improved by relaxing the siting constraints, although it may raise environmental and social concerns.

著者

岡本 遼太郎

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.136, no.3, pp.NL3_3-NL3_6, 2016-02-01 (Released:2016-03-01)

参考文献数

6

---

Today, we must develop alternative energies. However, Japan does not have enough land to build large power plant. Therefore we studied about small-sized wind power generation for the purpose of developing a windmill which is suitable for the wind condition of its installed location.

著者

古川 功一郎 舟越 節彦 川内野 寿博 高崎 真司 下條 敏一 平山 開一郎 曽我部 敏明 嶋村 武夫 野原 真一

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.1, pp.53-64, 2005 (Released:2005-04-01)

参考文献数

10

被引用文献数

1 1

---

This paper describes how to smoothly restore the power system from blackout using a hydro power plant. Various kinds of abnormal phenomena could occur during the period of blackouts and restoration. Taking various possible abnormal phenomena into account, the authors first performed an analytical study of power system restoration processes using the proposed method with a simplified power system model consisting of a generator, some transmission lines and transformers. Based on this study, an actual power system test was then carried out. A transformer voltage goes to increase after its voltage application. This voltage increase causes an over voltage problem to a transformer. The authors are proposing practical countermeasures on the over voltage problem at restoration with a hydro power plant.

著者

織田 慎一郎 見目 喜重 中川 重康 榊原 建樹

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.117, no.8, pp.1146-1151, 1997

被引用文献数

1

---

So far a single-stage neural network has been proposed to forecast insolation of next day. In the present paper, a multi-stage neural network is developed to reduce forecasting error further. A first-stage neural network forecasts average atmospheric pressure of next day from atmospheric pressure data of previous day. A second-stage neural network forecasts insolation level of next day from the average atmospheric pressure and weather data of previous day. A third-stage neural network forecasts insolation of next day form the insolation level and weather data of previous day. Meteorological data of Omaezaki, Shizuoka at April 1994 are chosen as input data. The insolation values forecasted by the multi-stage and the single-stage neural networks are compared with the measurement ones. The results show that the forecasting error is reduced to 24% (by the multi-stage) from 33% (by the single-stage).

著者

前田 進 山下 拓之 米谷 晴之 下畑 賢司 野村 達衛 泉 昭文

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 = 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.123, no.11, pp.1400-1410, 2003-11-01

---

Superconducting generators have many advantages such as increasing generation efficiency and improving power system stability etc. In Japan, 70MW class superconducting generators have been developed through the national project"Electric Power Application of Superconducting Technologies (1988-1999)". <BR>In this paper, performance evaluation of the rotor damper structure for the 70MW class model generator is discussed. Double-layered damper structure, which consists of a squirrel-cage warm damper and a single-layered cold damper was set as the target. As the first step, basic electromagnetic and thermal performances were obtained through the experimental model. In the following step, the 70MW model rotor damper structure was designed based on the experimental results and the rotor was manufactured. Evaluation of the damper structure of the 70MW rotor was carried out in the verification test from the technical view point of 'unbalance current capability', 'flux shielding' and 'generator reactance' etc. and satisfactory results were obtained. Consequently, it was proven that the damper structure had the performances to satisfy the requirements of the superconducting generators. Performances obtained from the experimental model, design of the 70MW model rotor and evaluation by the verification tests are described in this paper.

著者

佐々木 博司

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.12, pp.995-998, 1990

被引用文献数

1

著者

久保川 淳司 佐々木 博司 大久保 嘉人 餘利野 直人 横山 隆一 田辺 隆也

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.138-144, 1993

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In modern industrialized societies, it is mandatory to supply uninterruptedly high quality electric energy with modest cost while preserving better environments. This can only be realized through very sophisticated power system operations that compromise several contradictory factors stemming from economy, security and environment. Since these factors are in trade-off relationships to each other, they should be treated as such. A class of problems that simultaneously satisfy several criteria in trade-off relationships are called &ldquo;multi-objective optimization problems&rdquo;. Optimal power flow (OPF) has been regarded as the most powerful means to obtain such system operation plans, it only optimizes a single objective function.<br>This paper proposes an efficient solution methodology for a class of multi-objective optimal power flow problems which makes use of a heuristic search method. An optimal solution can be found in the proposed heuristic search method based on local information on a preference index which is arbitrarily chosen out of a given set of objectives. This circumvents the exhaustive evaluation of all non-inferior solutions which is needed in the existing multi-objective OPF algorithm proposed by the authors, thus dramatically reducing the solution time. The proposed method has been coded and applied to the IEEE 57 node test system. Simulation results have demonstrated the possibility of utilizing this method in on-line environments.

著者

久保川 淳司 大久保 嘉人 佐々木 博司 横山 隆一

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.118, no.3, pp.239-245, 1998

---

As the necessity of high quality electric power supply is increasing, it has been required to make up sophisticated power system operations in which several requirements stemming from economy, security and environmental aspects should simultaneously be satisfied. In general, a problem of satisfying several noncommensurable criteria is called a multi-objec-tive optimization problem. Although the most powerful means to obtain desirable system operations is optimal power flow (OPF), a straightforward application of the conventional OPF optimize only one objective and the remaining objectives must be treated as constraints. However, since such objectives are in trade-off relationships each other, it is necessary to develop an efficient multi-objective OPF.<br> In this paper, we shall propose a solution method of multi-objective OPF by means of fuzzy coordination. In the first step, the degree of satisfaction of Decision Maker on each objective would be maximized with a pre-specified member-ship function. The membership function would be updated in accordance with the DM's preference information and target value of the objective function. The degree of satisfaction will be improved step by step by updating the membership functions. Finally, the saticificing solution for the Decision Maker would be obtained. The proposed method has been applied to the IEEE 57 and 118 test system, producing successful results.

著者

植田 圭輔 高見澤 悠 岩本 伸一 加藤 義之 島津 昌之

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 = 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.131, no.2, pp.175-180, 2011-02-01

参考文献数

10

被引用文献数

1

---

With the high economic growth era until 1990s, the power demand increased sharply year by year. Therefore, the electric power utilities installed many electric power facilities along with the predicted demand. However, in recent years, fewer infrastructures have been installed because electric power demand growth is saturated due to low economic growth. Therefore, in electric power facilities planning, it has been necessary to form a rational renewal planning which also considers social influence factors such as the construction quantity. In this paper, we propose a new transmission renewal planning method using Supply-end Reserves and Line Flow Sensitivities. We carry out simulations for the IEEJ EAST 10-machine -O/V model system and determine the transmission planning priority order to confirm the validity of the proposed method.

著者

高嶋 武 大坪 昭 石橋 鐐造

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.103, no.3, pp.183-190, 1983-03-20 (Released:2008-12-19)

参考文献数

18

被引用文献数

1 1

著者

保川 忍

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.106, no.9, pp.769-776, 1986

著者

黄 〓 塚尾 茂之 田村 康男 岩本 伸一

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.114, no.12, pp.1288-1294, 1994

被引用文献数

1

---

With rapid growth of the number of literatures on nonlinear systems, nonlinearities existing in the systems under study have drawn much attention. Studies on the effects of nonlinearities in power systems have been becoming an increasingly important part of researches for the investigation of system stability. It is probable that hidden phenomena may unexpectedly emerge due tc the nonlinearities that are involved in load flow equations, generator swing equations and characteristics of control equipments and loads, etc.<br> This paper presents a new Catastrophe Theory application to nonlinear power systems. Making use of the concept of Duffing's equation, we show that a Catastrophe Theory analogy can be used to interpret unstable phenomena caused by system nonlinearities from the viewpoint of oscillations. When considering the system nonlinearities, due to ill-combination of system parameters and periodic disturbances, there may exist the characteristic &ldquo;jumps&rdquo; in system states corresponding to slow (quasi-dynamic) changes of the frequencies of periodic disturbances. With this Catastrophe Theory approach, a system bifur-cation set can be identified to assess the unstable phenomena of power systems.

著者

中村 勇太 原 亮一 北 裕幸 田中 英一

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.2, pp.107-115, 2018-02-01 (Released:2018-02-01)

参考文献数

39

被引用文献数

1 1

---

From growing interests in the environment issues, promotion of photovoltaic power generation (PV) is accelerated in the world. Meanwhile, rapid chargers (RCs) for popularized electric vehicles are being installed in urban areas. These two trends in distribution system might cause severer voltage fluctuation problems. On the other hand, a RC can provide the reactive power support, which is capable of voltage regulation. Based on this viewpoint, this paper proposes a new framework of voltage regulation, in which the reactive power compensation by RCs is actively utilized. The proposed voltage regulation method combines two different control functions with consideration for over-compensation avoidance. This paper ascertains the validity of proposed voltage regulation method through numerical simulations.

著者

佐伯 尚志 岩本 伸一

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.9, pp.765-772, 1992-09-20 (Released:2008-12-19)

参考文献数

11

---

When analyzing dynamical stability in power systems, there exist various errors. First, there are analyzing errors which occur in linearlizing non-linear systems on a particular operating condition. Secondly, there are adjusting errors of the parameter values which are the time constants and the gains of the control systems. However, the conventional representative techniques, such as the eigen value method, the Routh-Hurwitz method and the Nyquist method, cannot deal with these kinds of errors. Using these representative methods, if the parameters vary, we have to recalculate the whole system stability. In order to solve this kind of problem, this paper proposes a use of the Kharitonov theorem which is one of the robust control theories.