• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.3169-3171
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• 1999

One of the important purposes o Telecommunications power plant operation is to supply safe power for maintaining the reliable communication services. Therefore, the power plant operation support system is generally used for efficient and maintenance of power plant without the increment of the operation and maintenance staffs. To operate and maintain a number of power plants efficiently, Korea Telecom developed centralized power plant monitoring and control system. In this paper, the system feature and main functions are described.

• Proceedings of the KIEE Conference
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• 1997.07b
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• pp.603-605
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• 1997

The systematic and efficient operation of telecommunication power equipments is very important to the safe operation of telecommunication system. To achive that, Korea Telecom has developed a new centralized management system for telecommunication power equipments. The system configuration and main functions for the new developed system are described in this paper.

• Journal of Advanced Marine Engineering and Technology
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• v.21 no.3
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• pp.278-283
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• 1997

The rectifier is the main element in the telecom DC power system. This paper investigates the advantages and disadvantages of three rectifier techniques ; thyristor, ferro - resonant, and switched - mode. Compared with other techniques, the switched - mode rectifier tech¬nique offers several advantages such as higher efficiency, smaller size and weight, and lower audible noise. Technical requirements in telecom rectifier plant are also described. Finally, the future trends in telecom powering are discussed in connection with the advance oftelecom net¬works.

• Journal of Power Electronics
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• v.10 no.3
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• pp.219-227
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• 2010

Telecom supplies need to conform to low Total Harmonic Distortion (THD) and high Power Factor (PF) as per IEC 61000-3-2 and IEEE 519-1992 standards. These high rating power supplies use a three phase utility in which low THD and high PF are realized via various passive and active wave shaping schemes. In this paper, a new design for three phase telecom power supplies is presented with circuit parameter values optimized for high performance in terms of a low THD, high PF, low ripple and high line and load regulation using a suitable combination of various strategies. The performance of the power supply is validated by extensive simulations.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.11a
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• pp.432-432
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• 2004

• Proceedings of the KIEE Conference
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• 1997.07a
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• pp.279-281
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• 1997

Batteries as an emergency power of stationary standby service are required to provide a reliable source of DC power needed to aid in safe AC power failure. It is important that the properly action in early stage as soon as possible, when the battery's deterioration is detected. This paper describes a practical diagnostic technique to monitor the state-of-health of lead acid batteries in telecommunications power system.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.87-89
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• 2005

전력선통신은 다른 통신기술과 달리 표준화 작업이 현재 이루어지지 않고 있으며 타 모뎀과의 호환성이 없다는 단점이 있다. 그러나, 이러한 제약사항들을 극복함으로써 전력선통신의 개발 및 상용화 시기를 앞당길 수 있다. 본 논문에서는 전력선통신의 종합시험장 구축모델 및 시험기준 설계 방안에 관하여 논의하며 전력선통신기기와 관련된 적합성, 성능 및 안정성, 상호운용성에 관한 기준수립 방안에 관하여 고찰하여 전력선통신의 객관적인 성능지표를 마련하고자 한다.

• Proceedings of the KIEE Conference
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• 1996.11a
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• pp.323-325
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• 1996

The design of Intelligent Energy Saving Power System Controller (IESPSC) for Telecom DC power plants is proposed and presented in this paper. From the past experience. rectifiers for Telecom DC power plants have been operated inefficiently at light loads. IESPSC offers "novel load sharing" approach based on the knowledge of each unit's efficiency of paralleled rectifiers. Neural networks is used for identifying each rectifier's efficiency characteristic curve corresponding to load currents, which is in turn utilized to produce a system efficiency close to the maximum under all operating conditions. In addition, by limiting the number of operating units to the minimum while maintaining high efficiency at the determined loads, a drastic savings in operating cost can be achieved.

• Journal of Korea Society of Digital Industry and Information Management
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• v.6 no.1
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• pp.159-167
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• 2010

We research a competitive advantage of telecom bundling package of three mobile telecom company by figuring out utility that consumers perceived and focused on mobile telecom and high speed internet in one bundled package. As a method, conjoint analysis was applied. And in conclusion, consumers considered retaining mobile telecom company as the most important factor to them and branding as the following important one when one bundled package of telecom service is provided in total market. When the market is divided into two submarkets and the second largest submarket is analyzed personal bundled package was most important and three year agreement with a stipulated discount has the highest utility. As a result of this analysis, mobile telecom company managers need to organize bundled package after consideration of their current position and brand power in the market, and then devise proper market strategy

• Journal of Power Electronics
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• v.18 no.6
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• pp.1819-1829
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• 2018

A three-phase, three-switch, and three-level boost-type PWM rectifier (Vienna rectifier) is proposed as an active front-end power factor correction (PFC) rectifier for telecom loads. The proposed active front-end PFC rectifier system is modeled by the switching cycle average model. The relation between duty ratios and DC link capacitor voltages is derived in terms of the system input currents. Furthermore, the feasible switching states are identified and applied to the proposed system to reduce the switching stress and DC ripples. A detailed equivalent circuit analysis of the proposed front-end PFC rectifier is conducted, and its performance is verified through simulations in MATLAB. Simulation results are verified using an experimental setup of an active front-end PFC rectifier that was developed in the laboratory. Simulation and experimental results demonstrate the improved power quality parameters that are in accordance with the IEEE and IEC standards.