This article surveys the status of the international standards of CIM (Common Information Model). CIM is being focused from all power engineers, because the standards will contribute Smart Grid technologies largely. CIM defines the most promising information model to realize CDM (Canonical Data Model). However, task making the complete CDM for transmission EMS needs very large efforts, so that CIM is being on development stage. This Article reports usefulness of CIM and development status of international standards of CIM. Also, an example of utilization CIM, which is an outcome from the NEDO project entitled; Research for Promoting International Standardization on the Technology of Wide Area Situational Awareness (WASA) for Trunk Power System, is expressed.

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High penetration of renewable energy may affect electric power system, because the variations in renewable energy power generations are affected by climate and relatively higher than those of conventional plants. Meanwhile, the future of global economic conditions and technological progress are very large uncertainties. It is difficult to find out the optimal solution based on current conditions. In this paper, an optimal power generation mix model is proposed, which can properly deal the essence of real conditions and carry out a number of simulations efficiently. In order to illustrate the proposed model, several parameter analysis cases, such as CO₂ emission constraints, fuel prices, costs of PV and storage facilities, and differences by years are studied.

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The long-term generation scheduling in power utilities is aimed at maintaining power supply sufficiency and estimating fuel consumption. The multi-period constraints, such as allowable numbers of unit commitment on a thermal unit and fuel consumption under given total amount of fuel, need to be taken into appropriate consideration for practically economic scheduling in long-term scheduling horizon. Due to the large size and complexity of such scheduling problem, it is difficult to get the solution collectively in terms of stability and processing time in operational situations. We propose a new scheduling method which consists of “preparative processing” and “detailed optimization processing”. The former works to divide the long-term problem with the multi-period constraints in time unit of week according to quick and simplified scheduling result, and the latter to minimize total operation cost on the basis of those weekly partitioned problems. The processing starts with an optimal scheduling result excluding the two multi-period constraints aforementioned and proceeds to sequentially resolve the violation of the each constraint in quantitative consideration of interrelationship between them. This paper describes the validation and effectiveness of the proposed method through the real world example of Chubu Electric Power Company.

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Distributed generators (DGs) would be installed in distribution systems. Penetration of DGs may bring some technical difficulties into distribution systems operation. To improve the acceptability for DGs dissolving technical issues, new scheme of system operation should be discussed. The authors have investigated active network reconfiguration in distribution systems utilizing IT switches. This paper presents two online network reconfiguration schemes under the normal operation; one is distribution loss minimization and another is preventive operation for contingency in distribution system. In order to realize the latter scheme, this paper develops a restoration process for the contingencies.

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Although a Darrieus-type wind turbine has a high efficiency, its starting torque is small, which means that either a high wind speed or a specialized mechanism is required to make it begin rotating. This paper presents a new starting method based on an opening-and-closing aileron attached to the main blade of a Darrieus-type straight-bladed vertical axis wind turbine. To investigate the effect of the aileron, we conducted wind tunnel experiments to determine the starting torque and wind speed to initiate rotation. The ailerons tested were a fixed-angle aileron and two types of opening-and-closing ailerons. The H-type aileron comprised an aluminum plate with a spring-loaded hinge and aluminum angle adjuster. The R-type aileron comprised a plastic resin sheet and an aluminum angle adjuster. The turbines with the H- or R-type ailerons were designed to be normally open, but the aileron closes when wind flows against the head of the main blade.
Compared to the case of using no aileron, the starting torque for the turbine with the fixed-angle aileron is sometimes higher and sometimes lower, depending on the position angle. On average, there is no net increase in starting torque by the use of a fixed-angle aileron. In contrast, the starting torque for the 2-, 3- or 4-blade turbine with opening-and-closing ailerons is positive for all position angles and increases more than that without an aileron. The average starting torque for the turbine with H- and R-type ailerons is larger than that for the turbine without ailerons. In addition, the wind speed to initiate rotation for the turbines with H- and R-type ailerons is less than that for no aileron.

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This paper deals with theory construction on a novel fault location method using air-gap flux distributions of a synchronous generator connected to a power system. Air-gap fluxes are the sum of field fluxes and armature reaction fluxes. Changes in armature current and field current at fault contribute directly to the armature reaction fluxes and field fluxes, then resultant air-gap fluxes. Therefore, air-gap fluxes can be utilized to locate fault. To verify the validity of theoretical formula, we compared to the experiment result of the air-gap flux distributions.

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Recently, Zinc oxide (ZnO) microvaristors are being used in epoxy resin of direct molded air bushings to control the surface potential distribution. We proposed equivalent circuit models in order to simulate the electrical properties of ZnO microvaristors under high voltage (HV) applications in Epoxy resin and calculated their electrical properties by LTspice circuit simulator.

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