• Title, Summary, Keyword: Power quality

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The Design of control algorithm for 150kVA power quality compensator (150kVA급 전기품질 보상기기 제어 알고리즘 설계)

  • Jeon, Jin-Hong;Kim, Ji-Won;Chun, Yeung-Han;Kim, Ho-Young
    • Proceedings of the KIEE Conference
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    • pp.1070-1072
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    • 2001
  • In recent years, customers and power supplies are interested in power quality. Demands of customers are change from standard quality of distribution power system to various high quality of distribution power system. so, it is necessary to apply power quality compensator, in our project, we develop the power quality compensator of 150kVA which compensates power factor and voltage sag, interruption. it is very frequently occurred power qualify problems[1,2]. As a series and shunt compensator, power quality compensator consists of two inverters with common do link capacitor bank. It compensates the current quality in the shunt part and the voltage qualify in the series part. In this paper we present the design and control algorithm of power quality compensator. As a control algorithm is implemented by digital controller, we consider sample-and-hold of signals. In this simulation, we use EMTDC/PSCAD V3.0 software which can simulate instantaneous voltage and current.

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A web-based power quality monitoring system in the Substation Automation System (변전소 자동화 환경에서 웹 기반 전기품질 감시 시스템)

  • Park D. H.;Lim S. J.;Shin J. H.;Lim S. I.;Lee S. J.
    • Proceedings of the KIEE Conference
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    • pp.378-380
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    • 2004
  • Along with the increase of the importance of power quality, many various systems are dedicated in the analysis of power quality nowadays. But there still exists the same problems for realizing such kind of analysis systems well. One is the customization of the power quality measure devices; The other is an economic problem. This paper presents the usefulness and the advantage of the ICD (Intelligent Electronic Device) as the measure device of power quality And this paper detailedly describes the development procedure of web-based power quality monitoring system through ActiveX controls. Now this power quality monitoring system is already applied to the substation automation system.

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Power Quality Measurement and Analysis of Extra-High Voltage Customer (특고압 수용가의 전력품질 측정 및 분석)

  • Cho, Jae-Hyeong;Lee, Jong-Pil;Ji, Pyeong-Shik
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.64 no.4
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    • pp.286-290
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    • 2015
  • Power system is composed of a number of power devices and equipment. This factor affects the power quality is also displayed very complicated and varied. The accurate measurement and analysis of the causes of power quality problems is difficult. In preparing for these issues, there are many difficulties. In this study, Power quality of A public establishment of Chungbuk province were measured and analyzed. Measurement results of the fifth harmonic current was very large. Accordingly, the harmonic reduction will be needed. This research will be utilized as fundamental data to improve power quality for power utility and customer.

IEC61850 Process Bus Based Distributed Power Quality Monitoring (IEC61850 프로세서 버스 기반 분산형 전력품질감시)

  • Park, Jong-Chan;Kim, Byung-Jin
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.56 no.1
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    • pp.13-18
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    • 2007
  • In this paper, authors deal with an application of power quality monitoring using the Sampled Value which is described in the IEC61850 International Standard for substation communication. Firstly, while Merging Unit is designed as a process level device transmitting sensor data, the practical problems such as time delay compensation and optical fiber communication are issued. Secondly, the Sampled Value message which is proper to a power quality monitoring system is presented. Because the power quality monitoring system requests non time critical service comparing to protection and control applications, the Sampled Value service message structure is introduced to improve efficiency. At last, the power quality monitoring server having various power quality analysis functions is suggested to verify the performance of Merging Unit. With the diverse experiments, it is proved that the process bus distributed solution is flexible and economic for the power quality monitoring.

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.

A Model for Power Quality Control Mechanism for Electric Power Market (전력시장체제하에서의 전력품질제어 매커니즘에 대한 모델링)

  • Lee, Geun-Joon;Yun, Suk-Ho;Heydt, G.T.
    • Proceedings of the KIEE Conference
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    • pp.15-19
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    • 2002
  • To provide a specified power quality under electric market system is becoming an important issue for customers and utility company. However, there is no realistic infra-structure to design a power system for the specified power quality. Present electric market is operating under the economic point of view. The low price could be attractive. but the effect of low price and low power quality for the long time should be considered for the system safety. This paper presents a model which conceptualize the dynamic power quality control mechanism to minimize total cost of a society which is affected electric power quality. This model aims to produce a basic infra-structure to balance cost and quality under the electric market system.

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The Design of Control Algorithm for Unified Power Quality Compensator (3상 직병렬보상형 전력품질 보상장치(UPQC)의 제어 알고리즘 설계)

  • Jeon Jin Hong;Kim Tae Jin;Ryoo Hong Je;Kim Hwang Su
    • Proceedings of the KIEE Conference
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    • pp.351-353
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    • 2004
  • In recent years, customers and power supplies are interested in power quality. Demands of customers are change from standard quality of distribution power system to various high quality of distribution power system. so, it is necessary to apply power quality compensator. in our project, we develop the UPQC(Unfied Power Quality Compensator of 45kVA which compensates power factor and voltage sag, interruption. it is very frequently occurred power quality $problems^{[1-3]}$ As a series and shunt compensator, UPQC consists of two inverters with common do link capacitor bank. It compensates the current quality in the shunt part and the voltage quality in the series part. In this paper, we present the design and control algorithm for 4SkVA UPQC system. As a control algorithm is implemented by digital controller, we consider sample-and-hold of signals. In this simulation, we use EMTDC/PSCAD V3.0 software which can simulate instantaneous voltage and current.

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A Study on Technology for Power Quality Differentiated Supply in Power System (품질별 전력 차등 공급 기술의 검토)

  • Choi, Sang-Bong;Kim, Dae-Kyeong;Jeong, Seong-Hwan;Kim, Ho-Yong
    • Proceedings of the KIEE Conference
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    • pp.330-332
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    • 2001
  • This paper reviews technology for power quality differentiated supply in power system. Since price and power quality has been single goods in the light of customer-side view point but hereafter it is essential for power market to introduce multiple goods which is composed of differentiated combination between them. This paper should like to work out strategy for power quality differentiated supply in domestic power system by comparison characteristics of differentiated background and its relevant various theory.

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Digital-Controlled Single-Phase Unified Power Quality Conditioner for Non-linear and Voltage Sensitive Loads

  • Ryoo Hong-Je;Kim Jong-Soo;Kisck Dragos Ovidiu
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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    • v.5B no.4
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    • pp.374-381
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    • 2005
  • The ability to provide quality power has become a significant issue in power systems. The main causes of poor power quality are harmonic currents, poor power factor, supply-voltage variations, etc. A technique of achieving both active current distortion compensation, power factor correction and also mitigating the supply-voltage variation (sag or swell) at the load side is presented in this paper. The operation and rating issues of the proposed Single-phase Unified Power Quality Conditioner are also highlighted. To reduce the total cost while simultaneously increasing the performance, the system is fully digitally controlled using the fixed-point TMS320F240 digital signal processor. The performances of the UPQC, which is composed by shunt and series PWM controlled-converters, have been verified on a laboratory prototype.

A Study on the Improvement for Power Quality Problems Caused by Electrical Arc Furnace in Power Systems (전력계통에서 전기로 부하에 대한 전력품질 개선방안에 관한 연구)

  • Kim, Jae-Eon;Rho, Dae-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.8 no.3
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    • pp.444-453
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    • 2007
  • This paper deals with a powerful countermeasure for power quality problems caused by the operation of electrical arc furnace in bulk power systems. The rapid active load fluctuations of electrical arc furnace could produce several problems such as voltage flicker and active power oscillations. The typical methods using only the reactive power compensation have their own limitation in solving the power quality problems caused by active load variations. The coordination of both active and reactive power compensation is required to solve the power quality problems. This paper focuses on the impacts and the dynamic phenomena caused by the active load fluctuation. This paper proposes the optimal algorithm for the active power compensation based on the function of 1(n ratio and the concepts for the active power compensation. The results from a case study show that the proposed methods can be a practical tool for the power quality problems in power systems.

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