• Title, Summary, Keyword: Power quality

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Determining Optimal Custom Power Devices to Enhance Power Quality

  • Won Dong-Jun;Moon Seung-Il
    • KIEE International Transactions on Power Engineering
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    • v.5A no.3
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    • pp.280-285
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    • 2005
  • This paper proposes a novel method for determining the kind and rating of power quality solutions. To determine the kind of solution, event cause and direction are utilized. According to the event cause and direction, an adequate type of solution is determined for effective compensation. To rate the required capacity of solution, the concept of lost energy is adopted. Lost voltage, lost power and lost energy are calculated and the rating of the solution is determined to compensate a specific event. The rating method that utilizes the result of stochastic diagnosis is also proposed. A power quality index such as CP95 is adopted for solution suggestion. The method developed in this paper is applied to the test system and proved to be useful for enhancing the power quality of the customer system. It can provide customers with information pertaining to what is a proper and cost-effective solution among various compensating devices.

The development of synchronized phasor measurement device for real time power system control (실시간 계통제어를 위한 동기위상측정장치 개발)

  • Jeon, Jin-Hong;Kim, Hak-Man;Chun, Yeong-Han;Kook, Kyung-Soo;Kim, Ji-Won;Oh, Tae-Kyoo
    • Proceedings of the KIEE Conference
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    • pp.85-87
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    • 2000
  • In real-time power system control, it is essential to measure the power system variables which are voltage. current, real and reactive power, power factor, system frequency and etc. this variables can be estimated or calculated by the synchronized phasor informations of voltage and current. Therefore, the synchronized phasor measurement of voltage and current is very important to real-time power system control. So, we develop SPMD(Synchronized Phasor Measurement Device) for synchronized phasor measurement of voltage and current. In this paper, we present the design and implementation of SPMD for real-time phasor measurement and prove its performance by the test results.

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Improving the Quality of Customer Service of Electrical Power Supply using an Integrated Outage Management System

  • Sastry, M.K.S.
    • The Asian Journal on Quality
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    • v.7 no.3
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    • pp.70-81
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    • 2006
  • An Integrated Outage Management System (IOMS) is a utility owned, centralized information system. Using the Supervisory Control And Data Acquisition (SCADA) methodology, the IOMS integrates different databases and components of outage management systems to improve the quality of service of electrical power to customers. This paper describes the development of an IOMS and its related utility functionality. The design considerations, salient features, component integration, functional aspects, and implementation issues of the IOMS are discussed. Evidence shows that the IOMS implementation would result in improving the overall quality of electric power supply and effective outage management significantly.

Power Quality Disturbances Identification Method Based on Novel Hybrid Kernel Function

  • Zhao, Liquan;Gai, Meijiao
    • Journal of Information Processing Systems
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    • v.15 no.2
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    • pp.422-432
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    • 2019
  • A hybrid kernel function of support vector machine is proposed to improve the classification performance of power quality disturbances. The kernel function mathematical model of support vector machine directly affects the classification performance. Different types of kernel functions have different generalization ability and learning ability. The single kernel function cannot have better ability both in learning and generalization. To overcome this problem, we propose a hybrid kernel function that is composed of two single kernel functions to improve both the ability in generation and learning. In simulations, we respectively used the single and multiple power quality disturbances to test classification performance of support vector machine algorithm with the proposed hybrid kernel function. Compared with other support vector machine algorithms, the improved support vector machine algorithm has better performance for the classification of power quality signals with single and multiple disturbances.

Study on the Measuring of Power Quality for the Residental PV System (가정용태양광 발전설비의 전력품질 측정에 관한 연구)

  • Ahn, Jae-Min;Han, Woon-Ki;Jung, Jin-Soo;Kim, Sun-Gu;Kim, Jae-Chul
    • Proceedings of the KIEE Conference
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    • pp.2176_2177
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    • 2009
  • This paper describe the power quality measuring result of the inter-connected residental PV system. The power quality measuring for inter-connected residental PV system are important to verify their performance and effect of power distribution system with inter-connected residental PV system. Also, these power quality measuring and analysis are essential to improve electrical safety. In order to evaluate influence of power distribution system with inter-connected residental PV system, we measure and analyze power quality index such as power, voltage, current, harmonic, THD, flicker index, power factor and frequency using DEWE5000.

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Configurations of AC and DC-type Quality Control Center for a New Distribution System FRIENDS

  • Hayashi Yusuke;Saisyo Masaki;Ise Toshifumi;Tsuji Kiichiro
    • Proceedings of the KIPE Conference
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    • pp.497-501
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    • 2001
  • Unbundled power quality service is paid much attention under the circumstances of deregulation and diversification of needs of customers for quality and price of electric power. Moreover, distributed generators (DGs) such as photovoltaic generations and wind turbines will be introduced to distribution system more and more, and reverse flow of active power has possibility to cause new problems in the distribution system such as voltage rise of distribution line and protection problem. Flexible, Reliable and Intelligent Electrical eNergy Delivery System, which is called FRIENDS, has been proposed as one of promising distribution system for such requirements, and intensive studies are under way. One of features of the system is introducing Quality Control Center (QCC) into the system for unbundled power quality service and easy installation of DGs. Two types of QCCs for such purposes are proposed, and simulation results are shown in this paper.

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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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    • 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 Filcker Evaluation Considering Power Quality Disturbance of Power System (전력계통의 전력품질 외란을 고려한 플리커 평가에 관한 연구)

  • Jung, Seung-Bock;Kim, Jae-Chul;Lee, Bong-Yi;Cho, Hyun-Kyung
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • pp.391-393
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    • 2005
  • This paper studies flicker evaluation considering power quality disturbance. A flicker problem with light device irritates human's eyes. Also, the flicker problem has an influence on adverse effect such as rolling device and rotating device. However, a study of flicker evaluation is not complete. A flicker is measured and evaluated at monitoring point. But we consider power quality disturbances such as voltage sag and transient that cause fault and inverter/breaker switching. Power quality disturbances affects flicker evaluation. A flicker evaluation index increases. Therefore, we consider power quality disturbances. We detect voltage sag and transient using wavelet and evaluate flicker without flicker index including power quality disturbances.

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Study on the measuring system of power quality for transmission system (송전계통의 전기품질 측정 시스템에 관한 연구)

  • Kim Yeoung-Noh;Shin Bong-Il;Lee Hee-Chul;Kwak No-Hong;Jeon Young-Soo;Park Sang-Ho;Lee Il-Moo
    • Proceedings of the KIPE Conference
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    • pp.432-434
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    • 2006
  • The additional matters appear to be considered in several aspects for building up power-quality measuring system of transmission system(high voltage system) compared to distribution system(middle or low voltage system). Like in distribution system, input signals are also received from PT and CT source of voltage and current respectively in transmission system and applied in accordance with a certain rate. In this case, very big error rate can be occurred according to the specification of the measuring system as the applying rate is bigger than in distribution system beyond comparison. In addition, when the abnormal signal occurred such as sag/swell, interruption, transient etc., power quality of other sires linked to the system also should be checked to find the accurate cause of the abnormal power-quality signals from the corresponding. site. Accordingly, the accurate diagnosis on the condition of power quality for the system depends on the way how the synchronization system is brought along for each site. This paper will suggest the solution for the most effective system building focused on how to solve the problem of the error rate and synchronization described in the above when building up the measuring system of power quality for transmission system.

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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
    • The 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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