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Kubota S.,Toko Electrical Corporation | Yamamoto K.,University of Electro - Communications
World Academy of Science, Engineering and Technology | Year: 2010

This study aims to identify the current situation and problems of environmental statement for major four home appliances (refrigerators, washing machines, air conditioners and television receivers) sold at online stores in Japan, and then to suggest how to improve the situation, through a questionnaire survey conducted among businesses that operate online stores and online malls with multiple online stores. Results of the study boil down to: (1) It is found out that environmental statement for the home appliances at online stores have four problems; (i) less information on "three Rs" and "chemical substances" than the one on "energy conservation", (ii) cost for providing environmental statement, (iii) issues associated with a label and mark placement, and (iv) issues associated with energy conservation statement. (2) Improvements are suggested for each of the four problems listed above, and shown are (i) the effectiveness of, and need to promote, a label and mark placement, (ii) cost burden on buyers, and (iii) need of active efforts made by businesses and of dissemination of legal regulations to businesses.


Yamaguchi T.,Toko Electrical Corporation | Shiozawa D.,Toko Electrical Corporation | Rokunohe T.,Hitachi Ltd. | Kida J.,Japan AE Power Systems Corporation | Zhang W.,Japan AE Power Systems Corporation
IEEJ Transactions on Power and Energy | Year: 2012

Optical current transformers (optical CTs) have features that they can be made much smaller and lighter than conventional electromagnetic induction transformers by their simple structure, and contribute to improvement of equipment reliability because of their excellent surge resistance performance. Authors consider optical CTs to be next generation transformers, and are conducting research and development of optical CTs aiming to apply to measuring and protection in electric power systems. Specifically we developed an independent-type optical CT by utilizing basic data of optical CTs accumulated for large current characteristics, temperature characteristics, vibration resistance characteristics, and so on. In performance verification, type tests complying with IEC standards, such as short-time current tests, insulation tests, accuracy tests, and so on, showed good results. This report describes basic principle and configuration of optical CTs. After that, as basic characteristics of optical CTs, conditions and results of verification tests for dielectric breakdown characteristics of sensor fibers, large current characteristics, temperature characteristics, and vibration resistance characteristics are described. Finally, development outline of the independent-type optical CT aiming to apply to all digital substation and its type tests results are described. © 2012 The Institute of Electrical Engineers of Japan.


Kurosawa K.,Tokyo Electric Power Company | Kondo R.,Tokyo Electric Power Company | Nasukawa S.,Tokyo Electric Power Company | Yamaguchi T.,Toko Electrical Corporation | Amano K.,Fujikura Ltd
Electrical Engineering in Japan (English translation of Denki Gakkai Ronbunshi) | Year: 2012

Fault point locating systems based on surge current detection have recently been used for fast recovery of underground transmission lines from faults. Electromagnetic induction type sensors have mainly been used for the detection of surge current. However, they are susceptible to electromagnetic noise which causes unstable system operation. To solve this problem, Tokyo Electric Power Co., Toko Electric Corporation, and Fujikura Ltd. jointly developed a new system using optical fiber current sensors. Copyright © 2011 Wiley Periodicals, Inc.


Yamada T.,National Metrology Institute of Japan | Kon S.,National Metrology Institute of Japan | Hashimoto N.,Toko Electrical Corporation | Yamaguchi T.,Toko Electrical Corporation | And 3 more authors.
IEEE Transactions on Power Delivery | Year: 2012

A high-accuracy error measurement system for calibration of digital-output equipped electronic current transformers (ECTs) is described. The system has been developed in conformity with the requirements for digital information networks in IEC 61850-9-2 and for accuracy class and error measurement procedures in IEC 60044-8. The system has also been designed to achieve simultaneous and synchronous samplings between an ECT/MU and a reference measuring unit, a procedure for capturing and filtering sampled value (SV) packets and data processing using the discrete Fourier transform with error compensations for an integrating analog-to-digital converter. The system employs a prototype commercial digital-output equipped ECT consisting of an optical current transformer (OCT) and a merging unit (MU). The error sources of the system are discussed for the error compensations and uncertainty estimations. Based on the principle of the system, the accuracy and temperature dependence of the prototype OCT/MU are evaluated and are confirmed to be within the limits of errors of accuracy class 0.2S. © 1986-2012 IEEE.


Patent
Hitachi Ltd. and Toko Electrical Corporation | Date: 2012-10-31

An installation base is secured to part of outer peripheral surface of cylindrical container 1 which has electric conductor 2 arranged thereinside, and a case which stores a Faraday-effect element is detachably secured to the installation base. Faraday-effect element 10 having two optical fibers 24A, 24B of prescribed dimensions, to provide first and second optical paths 11A, 11B maintained in parallel with a predetermined interval therebetween and placed so as to intersect axial direction of electric conductor 2, and having mirror 12 which reflects linearly polarized light at one end surface of each optical fiber. Linearly polarized light from the same light source injected into each of the optical paths 11A, 11B, and current flowing in electric conductor 2 is measured base on the Faraday rotation angle of the linearly polarized light reflected and returned from mirror 12.


Trademark
Toko Electrical Corporation | Date: 2013-02-22

COMPUTER HARDWARE AND SOFTWARE SYSTEMS FOR USE IN MEASURING, MONITORING, ANALYZING, TRANSMITTING, DISPLAYING AND CONTROLLING POWER USAGE, GAS USAGE, WATER USAGE, TEMPERATURE, HUMIDITY AND ENVIRONMENTAL CONDITIONS IN BUILDINGS AND INDUSTRIAL AND COMMERCIAL FACILITIES; COMPUTER SOFTWARE FOR USE IN MEASURING, MONITORING, ANALYZING, TRANSMITTING, DISPLAYING AND CONTROLLING POWER USAGE, GAS USAGE, WATER USAGE, TEMPERATURE, HUMIDITY AND ENVIRONMENTAL CONDITIONS IN BUILDINGS AND INDUSTRIAL AND COMMERCIAL FACILITIES.

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