• Title/Summary/Keyword: Power quality

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SSR Control by Damping Controller of TCSC (TCSC의 Damping 제어를 이용한 SSR 제어)

  • Jeon, Jin-Hong;Chun, Yeong-Han;Kim, Ji-Won;Kim, Tai-Hyun;Kim, Hak-Man;Kook, Kyung-Soo
    • Proceedings of the KIEE Conference
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    • 2000.11a
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    • pp.142-144
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    • 2000
  • This paper presents an auxiliary TCSC controller designed for damping SSR. Damping controller for SSR is designed in frequency domain for suppressing resonance. The SSR phenomenon and the performance of damping controller simulated by using PSCAD/EMTDC. In this simulation. the power system model for SSR is IEEE benchmark Model and TCSC is simplified to controllable impedance model.

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Bus Power Quality Index and Cost based on Load-Voltage Characteristics (부하의 전압특성을 고려한 모선별 전력품질 지표 및 가격 산정기법)

  • Lee, Geun-Joon;Heydt, G.T.
    • Proceedings of the KIEE Conference
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    • 2002.11b
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    • pp.9-14
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    • 2002
  • In front of the opening of electric distribution market in 2004. it is indispensable to have a proper estimation of power quality index and power quality cost calculation mechanism are indispensable to stabilize highly industrialized society and to vitalize the investment for electric power system. However, there were not enough measures to reflect the voltage characteristics such as voltage sags and interruptions which make electric load in unstable operation. This paper suggests power quality index(LDI) and power quality cost(LDC) which translate various kinds of voltage records into load drop index and cost based on aggregated load CBEMA curve. A sample calculation result shows that this method can produces the acceptable power quality index and costs for utilities and customers requirements.

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A Study on the Global Management Strategy for Product Quality Assurance Based on Brand Power and Country of Origin Effect (글로벌 품질보증 경영 전략에 관한 연구: 브랜드 명성 및 제조 국가 이미지를 중심으로)

  • Hwang, Hee-Joong
    • Journal of Distribution Science
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    • v.11 no.2
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    • pp.23-33
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    • 2013
  • Purpose - Numerous studies have tried to assess the role of a warranty as an explanatory instrument for product quality. While one study argued that manufacturers signal their superior quality to consumers by extending the duration of a warranty, quality is not necessarily related to warranty and a warranty for a short duration is a sign of high product quality. However, there are limitations to measuring product quality in terms of a single variable such as a warranty. Some other studies have evaluated the influence of brand power or value and price on the supposed quality of a product while the influence of warranty was found to be insignificant. Research design, data, methodology - The study analyzes the influence of brand power and the country of origin effect on consumers' perception of product quality in line with warranty and establishes a priority strategy. Especially, consumer experience has a significant influence on state of the art technology products like applied home electronics as these goods are generally quite expensive and consumers expend significant energy in purchasing them, so the associated warranty and brand can have a critical role in the decision making process. The price of the product was excluded in this discussion as it continually varies with the market share of the product. Results - The results of the analysis are as follows: First, each of the factors such as the standard of the warranty, brand power, and country of origin effect influences the degree of satisfaction of an individual. Second, the factors brand power and quality of the warranty interact both complementarily and synergistically at a time, depending on the brand power. As brand power is more significant, the degree of satisfaction is greater in case of products with low quality warranty compared to those with high quality warranty. Third, the brand power and country of origin effect present a complementary interaction. Fourth, the country of origin effect and quality of a warranty interact synergistically. Conclusions - Thus, the higher the quality of warranty, greater is the increment in the degree of satisfaction. The comprehensive study on the effect of the country of origin on the purchase decision process and the degree of satisfaction compared to the other elements shows that in case of Japanese and Korean markets the brand power of a company is desirable in sustaining the quality of warranty to the industrial average. Also, there is no significant improvement in the perceived quality of the product when the quality of the warranty is lowered. Therefore, the warranty effect diminishes when the value of the brand is known, while it perishes when both the brand power and the country of origin effect are strong enough.

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A Study on the Single Phase Voltage-Controlled Active Power Filter for Power Quality Improvement (전력품질 개선을 위한 단상 전압제어형 능동전력필터 시스템에 관한 연구)

  • 손진근
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.52 no.5
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    • pp.238-245
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    • 2003
  • In this paper, a single Phase voltage source voltage-controlled active power filter(APF) for power quality improvement was proposed. The proposed APF has the performance of harmonic suppression and unity power factor correction. The performance of harmonic suppression can be obtained by controlling the waveshape of the APF output voltage to be sine wave. And, unity power factor is controlled by the reactive power control loop of the APF output. Simulation and experimental results using diode rectifier showed that the voltage-controlled APF, unlike the current-controlled APF, can reduce the voltage harmonics as well as current harmonics. Also the results showed that the input dover factor and power quality were greatly improved.

Power Quality Analysis of Wind Farms interconnected in Jeju System during HVDC Overhaul (HVDC Overhaul 기간 중 제주계통에 연계된 풍력발전의 전력품질 분석)

  • Chae, Woo-Kyu;Yoon, Gi-Gab;Cho, Seong-Soo;Jung, Won-Wook
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.11
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    • pp.1946-1953
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    • 2008
  • Power system of Jeju is interconnected to the mainland using HVDC and that is also interconnected to three wind farms. It will be difficult to control of Jeju power system if HVDC is disconnected or HVDC is overhauled under large scale wind farms interconnected. We measured and analysed the power quality of two substation and two wind farms to assess that wind farms have an effect on Jeju system during the HVDC overhaul last May. We concentrated on the power quality like frequency, voltage variation, voltage harmonics, current harmonics, flicker. We can found that the frequency of Jeju system is very unstable during overhaul, so the frequency of Jeju system can be variated easily by wind farm's rapid output power variation. There are some benefits and weak points in power quality between two wind farms because each wind farm is consist of different wind turbines.

Development of Power Quality Monitoring System (전력품질 감시 시스템 개발(3) : 전력품질 감시 시스템)

  • Bahng, Soon-Jeong;Kim, Young-Il;Han, Jin-Hee;Yoon, Tai-Wook
    • Proceedings of the KIEE Conference
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    • 2003.11a
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    • pp.158-160
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    • 2003
  • Recently, with the increasing use of power semiconductors and microprocessors which are very sensitive to little change of power quality and for coping positively with anticipating power quality disputes between power providers and consumers which are possible to occur by of power market being formed, the power quality problem has gained preponderance among the contemporary research areas. To serve these purposes, this paper is described the integrated system for power quality monitoring, which provides speedy and powerful functions by analyzing the Event data and diverse graphic interfaces for user.

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Lithium-ion Battery Energy Storage System for Power Quality Improvement in Electrical Propulsion Ships (전기추진선박의 전력품질 개선을 위한 리튬-이온 배터리 에너지저장시스템 적용)

  • Ku, Hyun-Keun;Seo, Hye-Rim;Kim, Jang-Mok
    • The Transactions of the Korean Institute of Power Electronics
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    • v.20 no.4
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    • pp.351-355
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    • 2015
  • This paper explained the application of a lithium-ion battery energy storage system to electric propulsion ships. The power distribution in electric propulsion ships has low power quality because of the variation in the power consumption of the propulsion motor. For proper operation of the ship, the power quality needs to be improved, and the battery energy storage system is used to solve power-quality problems. The simulation models of electric propulsion ship and battery energy storage systems are constructed on MATLAB/Simulink to verify the improvement in power quality. The proposed system is applied in various scenarios of the propulsion motor state. The power quality achieved by using the battery energy storage system in both voltage and frequency satisfies the standards set by IEC-60092/101.

Power Quality Monitoring System with a New Distributed Monitoring Structure

  • Won, Dong-Jun;Chung, Il-Yop;Kim, Joong-Moon;Ahn, Seon-Ju;Moon, Seung-Il;Seo, Jang-Cheol;Choe, Jong-Woong
    • KIEE International Transactions on Power Engineering
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    • v.4A no.4
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    • pp.214-220
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    • 2004
  • Power quality monitoring is the cornerstone for power quality analysis, diagnosis and improvement. The measurement of power quality (PQ) evolves from instantaneous metering to continuous monitoring. Furthermore, recent technologies enable us to construct more flexible, reliable, rapid and economical power quality monitoring system (PQMS). Therefore, this paper presents an improved PQMS with a new distributed monitoring structure. The proposed PQMS consists of a PQ meter, PQ analyzer and GUI. The PQ meter only collects raw data and the PQ analyzer performs power quality analysis. It has several advantages compared to conventional structures in economic efficiency, modularity, speed, etc. PQ monitoring algorithms to catch steady-state trends and to detect PQ events are also adapted to the proposed structure. Using the proposed structure and monitoring algorithm, a prototype PQMS is constructed and real-time testing is performed.

Analysis of Power Quality for Extra-High Voltage Customers by Field Tests (실측에 의한 특고압수용가의 전력품질 분석)

  • Ji, Pyeong-Shik;Moon, Jong-Fil
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.61 no.2
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    • pp.82-86
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    • 2012
  • Recently, due to the expansion of electric power demands, nonlinear load such as converters and inverters connected to the electric power distribution system, and extensive application of harmonic generation sources with power electric devices, disturbance of the electric power system and its influences on industries have been continuously increasing. In this research, power quality was analyzed for 11 extra-high voltage customers by considering voltage unbalance condition, power factor, THD and TDD. This research will be utilized as fundamental data to improve power quality for power utility.

Substation Power Quality Test of Hanvit 350 running (한국형 고속열차 주행시 전철변전소 전력품질 시험)

  • Lee, Tae-Hyung;Park, Choon-Soo;Im, Young-Chan;Choi, Seong-Hoon
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.1479-1481
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    • 2007
  • It is important to evaluate the power quality at a substation when a test train is running. Especially, the Korea Electric Power Company(KEPCO) restrict the power quality generated from the electrical train within limited value. So, this paper represents the results of the power quality test when Hanvit 350 is running at the KTX high speed line and the assessment.

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