• Title/Summary/Keyword: Electrical response

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Response Surface Methodology based on the D-optimal Design for Cell Gap Characteristic for Flexible Liquid Crystal Display (D-optimal Design을 이용한 Flexible 액정 디스플레이용 셀 갭 특성에 대한 반응 표면 분석)

  • Ko, Young-Don;Hwang, Jeoung-Yeon;Seo, Dae-Shik;Yun, Il-Gu
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.11a
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    • pp.510-513
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    • 2004
  • This paper represents the response surface model for the cell gap on the flexible liquid crystal display (LCD) process. Using response surface methodology (RSM). D-optimal design is carried out to build the design space and the cell gap is characterized by the quadratic model. The statistical analysis is used to verify the response surface model. This modeling technique can predict the characteristics of the desired response, cell gap, varying with process conditions.

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Risk-Based Allocation of Demand Response Resources Using Conditional Value-at Risk (CVaR) Assessment

  • Kim, Ji-Hui;Lee, Jaehee;Joo, Sung-Kwan
    • Journal of Electrical Engineering and Technology
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    • v.9 no.3
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    • pp.789-795
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    • 2014
  • In a demand response (DR) market run by independent system operators (ISOs), load aggregators are important market participants who aggregate small retail customers through various DR programs. A load aggregator can minimize the allocation cost by efficiently allocating its demand response resources (DRRs) considering retail customers' characteristics. However, the uncertain response behaviors of retail customers can influence the allocation strategy of its DRRs, increasing the economic risk of DRR allocation. This paper presents a risk-based DRR allocation method for the load aggregator that takes into account not only the physical characteristics of retail customers but also the risk due to the associated response uncertainties. In the paper, a conditional value-at-risk (CVaR) is applied to deal with the risk due to response uncertainties. Numerical results are presented to illustrate the effectiveness of the proposed method.

Frequency Response Method Based Controller Design of High-Speed Pantograph for Improving Transient Response (과도응답 개선을 위한 고속 팬터그래프의 주파수 응답 기법 기반 제어기 설계)

  • Lee, Joo-Won;Jo, Nam-Hoon
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.27 no.7
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    • pp.95-100
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    • 2013
  • In this paper, we propose an active controller for high-speed pantograph in order to improve the transient response. Electrical power is delivered from a catenary to the train via a pantograph and thus it is very important to regulate the contact force between catenary and pantograph. By regarding the catenary displacement as an unknown disturbance input and analyzing the frequency response from the disturbance to contract force. we present an active controller that utilizes the lead compensator and resonant controller. It is shown by the computer simulation that the substantial improvement in transient response can be achieved by the proposed controller.

A Study on Fast Response Time for Twisted Nematic Liquid Crystal Display

  • Lee, Kyung-Jun;Jeon, Yong-Je;Hwang, Jeoung-Yeon;Seo, Dae-Shik;Jeon, Youn-Hak;Nam, Sang-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.04b
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    • pp.121-123
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    • 2002
  • Fast response characteristics of twisted nematic liquid crystal display (TN-LCD) cell with different nematic liquid crystals (NLCs) and cell gap on a rubbed polyimide (PI) surface were studied. High transmittance and fast response time of the TN-LCD on the rubbed PI surface were achieved by using high birefringence ($\Delta$ n) and low cell gap. It is considered that the transmittance and response time of the TN-LCD on the rubbed PI surface decreased as $\Delta$ nd decrease.

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An Analysis on Power Demand Reduction Effects of Demand Response Systems in the Smart Grid Environment in Korea

  • Won, Jong-Ryul;Song, Kyung-Bin
    • Journal of Electrical Engineering and Technology
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    • v.8 no.6
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    • pp.1296-1304
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    • 2013
  • This study performed an analysis on power demand reduction effects exhibited by demand response programs, which are advanced from traditional demand-side management programs, in the smart grid environment. The target demand response systems for the analysis included incentive-based load control systems (2 month-ahead demand control system, 1~5 days ahead demand control system, and demand bidding system), which are currently implemented in Korea, and price-based demand response systems (mainly critical peak pricing system or real-time pricing system, currently not implemented, but representative demand response systems). Firstly, the status of the above systems at home and abroad was briefly examined. Next, energy saving effects and peak demand reduction effects of implementing the critical peak or real-time pricing systems, which are price-based demand response systems, and the existing incentive-based load control systems were estimated.

The Design of an Optimal Demand Response Controller Under Real Time Electricity Pricing

  • Jin, Young Gyu;Choi, Tae-Seop;Park, Sung Chan;Yoon, Yong Tae
    • Journal of Electrical Engineering and Technology
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    • v.8 no.3
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    • pp.436-445
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    • 2013
  • The use of a demand response controller is necessary for electric devices to effectively respond to time varying price signals and to achieve the benefits of cost reduction. This paper describes a new formulation with the form of constrained optimization for designing an optimal demand response controller. It is demonstrated that constrained optimization is a better approach for the demand response controller, in terms of the ambiguity of device operation and the practicality of implementation of the optimal control law. This paper also proposes a design scheme to construct a demand response controller that is useful when a system controller is already adapted or optimized for the system. The design separates the demand response function from the original system control function while leaving the system control law unchanged. The proposed formulation is simulated and compared to the system with simple dynamics. The effects of the constraints, the system characteristics and the electricity price are examined further.

Development of Demand Response Operation System for Load Aggregators (부하관리사업자용 수요반응 운영 시스템 개발)

  • Kim, Ji-Hui;Moon, Guk-Hyun;Joo, Sung-Kwan;Oh, Jae-Cheol
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.12
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    • pp.2221-2224
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    • 2011
  • During an emergency due to a shortage of power, a load aggregator (LA) can use the demand response operation system to deploy demand response resources (DRRs) through various demand response (DR) programs. This paper introduces the demand response operation system for a load aggregator to manage various demand response resources in a smart grid environment.

Electrical Impedance Response Model of Concrete in Setting Process (응결 과정 콘크리트의 전기 임피던스 응답 해석 모델)

  • Shin, Sung Woo;Hwang, Garam;Lee, Chang Joon
    • Journal of the Korean Society of Safety
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    • v.29 no.5
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    • pp.116-122
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    • 2014
  • Assessment of setting process of concrete is important as it provides useful information to schedule concreting work in construction site. Electrical impedance measurement method, which utilizes the change of electrical resistance of concrete, has been applied to assess setting process of cement-based materials. However, the applicability of the method has been demonstrated only for cement paste and mortar. The main purpose of this research is to develop the electrical impedance based setting process assessment for concrete. To this end, electrical impedance response model for concrete should be developed in advance since it is essential to estimate the electrical resistance of concrete from measured impedance response. The electrical resistance of concrete is a key parameter for the setting process assessment. In this study electrical impedance responses of the concrete in setting process are measured and analyzed. Thereby, an electrical impedance response model of the liquid state concrete is developed and schematically validated.

Predictive current control for fast response of generator excitation system (발전기 여자 시스템 속응성 개선을 위한 예측제어 전류 기법)

  • Lee, B.K.;Moon, S.P.;Choi, J.H.;Rhew, H.W.
    • Proceedings of the KIEE Conference
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    • 1997.11a
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    • pp.416-418
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    • 1997
  • Stable power source and fast control response are important for the generator excitation system. To stabilize the control of excitation circuit the PI controller for excitation current has been used. But the response of the system with this conventional control technique is very poor, especially in transient response with a predictive current control, the response of the excitation system can be improved. In this study, it is verified by the PSIM simulation.

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A Study on Decision-making Criteria in Industrial Sector for Electric Load Aggregation (수요반응자원으로서 산업용 부하의 매집 우선순위 결정 기준에 관한 연구)

  • Kim, Sung-Yul;Kim, Dong-Min
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.65 no.6
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    • pp.946-954
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    • 2016
  • Energy industry is undergoing a paradigm shift in customer participation in the smartgrid. Customers traditionally consume electrical power. But nowadays not only do they generate electricity from private distributed generations, they can participate in demand response programs with their negawatt power which means a theoretical unit of power representing an amount of energy saved. Therefore development of decision-making criteria for electric load aggregation becomes a greater consideration as an amount of energy saved from demand response resources increases. This paper proposes load aggregators' decision-making criteria in the industrial sector where it made up the largest portion in demand response portfolio in order to assure reliability performance for demand response resources.