• 제목/요약/키워드: Power Limit

검색결과 1,457건 처리시간 0.033초

재생에너지 출력제한에 따른 출력량 배분 방안 연구 (The Study on the Method of Distribution of output according to Power Limit of Renewable Energy)

  • 명호산;김세호
    • 전기전자학회논문지
    • /
    • 제23권1호
    • /
    • pp.173-180
    • /
    • 2019
  • 재생에너지의 점유율 증가에 의하여 출력이 제한되는 사례가 발생하고 있다. 전형적으로 풍력발전의 발전량이 높고 부하가 낮은 새벽시간에 출력제한이 주로 발생하였으나, 태양광발전의 점유율이 증가하면서 낮 시간에 풍력발전의 출력이 제한되는 사례가 발생하고 있다. 현재의 전력계통 운영 상황에서는 태양광발전의 점유율이 증가할수록 풍력발전의 출력 제한이 더욱 증가시킬 것이며, 이는 풍력발전 운영자의 어려움을 가중시킬 것이다. 본 논문에서는 발전원 그리고 발전소별 출력 제한을 위하여 전력계통의 운영 어려움 유발하는 에너지원의 우선 제약을 기준으로 설정하여 기준에 따라 재생에너지의 출력 제한량을 분배하는 방안을 제시하였다.

철심과 권선을 이용한 전류제한기에 적용시킨 안정화층이 다른 YBCO Coated Conductor의 전류제한 특성에 관한 연구 (The Study on the Current Limiting Characteristics of YBCO Coated Conductor with Different kinds of Stabilization Layer Applied to SFCL Using Iron Core and Coil)

  • 이동혁;두호익;김용진;한병성;임성우;한상철;이정필
    • 한국전기전자재료학회논문지
    • /
    • 제23권10호
    • /
    • pp.788-792
    • /
    • 2010
  • The yttrium-barium-copper-oxide (YBCO) coated conductor, which supplement the fault of the existing superconducting current-limit materials YBCO thin film, bismuth-strontium-calcium-copper-oxide(BSCCO) wire and bulk, has been improved its mechanical weakness and has high index; hence, after quench YBCO coated conductor could limit the fault current effectively because of fast resistance occurrence speed. Furthermore, it has wide applicable area as an current limit material because it shows different resistance occurrence tendency by the thickness and kind of stabilization material sputtered on the superconducting layer. Therefore, many researchers are carrying out the study of application of YBCO coated conductor to superconducting fault current limiter (SFCL) for making high quality current limit element, based on resistance type. On the other hand, the study for other type except resistance type has been rarely conducted for the application of YBCO coated conductor to SFCL as an current limit element. Consequently, in this study, YBCO coated conductor with different stabilization layer Cu and Stainless steel, is applied to SFCL using iron core and coil, and examine the many index points as an current limit element, such as current limit characteristic, the tendency of resistance occurrence, response time, the temperature trend for stability.

Evaluation of limit load analysis for pressure vessels - Part I: Linear and nonlinear methods

  • Chen, Xiaohui;Gao, Bingjun;Wang, Xingang
    • Steel and Composite Structures
    • /
    • 제22권6호
    • /
    • pp.1391-1415
    • /
    • 2016
  • Limit load of pressure bearing structures was reviewed in this article. By means of the finite element analysis, limit load of pressurized cylinder with nozzle was taken as an example. Stress classification method and Elastic-plastic finite element analysis combining with limit load determination methods were used to determine limit load of cylinder with nozzle. Comparison of limit load determined by different methods, the results indicated that limit load determined by linearization method was the smallest. Limit load determined by twice elastic slope criterion was the nearest than experimental results. Elastic-plastic finite element analysis had comparably computational precision, but required time consuming. And then the requirements of computer processing and storage capacity by power system became higher and higher. Most of criteria for limit load estimation included any human factors based on a certain substantive characteristics of experimental results. The reasonable criterion should be objective and operational.

가스방전관(GDT)을 적용한 서지보호장치 회로의 DC 동작전압 최적조건 고찰 (Optimization of DC Operating Voltage for GDT-Adopted SPD)

  • 최종민;전태현
    • 조명전기설비학회논문지
    • /
    • 제26권7호
    • /
    • pp.92-98
    • /
    • 2012
  • It is made compulsory to install SPD for the purpose of protecting electric and electronic devices when an abnormal voltage such as lightning occurs to power line using power frequency of 60Hz. Recently, the high speed communication technology utilizing power line is receiving attention again as a communication technology for smart grid. The SPD influences the performances of power line communication when using SPD and power line communication system together. In order to improve the performance of power line communication, a proposed scheme for series connection of gas discharge tube to ZnO varistor was presented. This paper measured the impacts of series connection of GDT to SPD using ZnO varistor on the limit voltage of Class III SPD. This paper also presented the DC operating voltage of GDT which satisfies the limit voltage of power line communication system and SPD simultaneously.

Power Quality Early Warning Based on Anomaly Detection

  • Gu, Wei;Bai, Jingjing;Yuan, Xiaodong;Zhang, Shuai;Wang, Yuankai
    • Journal of Electrical Engineering and Technology
    • /
    • 제9권4호
    • /
    • pp.1171-1181
    • /
    • 2014
  • Different power quality (PQ) disturbance sources can have major impacts on the power supply grid. This study proposes, for the first time, an early warning approach to identifying PQ problems and providing early warning prompts based on the monitored data of PQ disturbance sources. To establish a steady-state power quality early warning index system, the characteristics of PQ disturbance sources are analyzed and summed up. The higher order statistics anomaly detection (HOSAD) algorithm, based on skewness and kurtosis, and hierarchical power quality early warning flow, were then used to mine limit-exceeding and abnormal data and analyze their severity. Cases studies show that the proposed approach is effective and feasible, and that it is possible to provide timely power quality early warnings for limit-exceeding and abnormal data.

AGC 운용에 있어서의 원격 On-line 최대 증감발율 취득 기법 (Remote On-line Determination of the Load Rate Limit of Generation in AGC)

  • 권순만;전동훈;문원용;김석주
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2000년도 추계학술대회 논문집 학회본부 A
    • /
    • pp.119-121
    • /
    • 2000
  • The possibility of a remote on-line determination of the maximum load rates that are basically set at generation plants is investigated in automatic generation control (AGC) system. Energy management system (EMS) generates a test input to a remote power plant to get the samples of the generator output. Then from the samples it can be attempted to determine an approximate value of the load rate limit set by the operator. It is shown in computer simulation that in actual power plants the limit can be approximately determined from the input-output characteristics of the plants for a unit-step input.

  • PDF

배전계통에서 분산전원 운전가능 범위에 대한 연구 (A Study on Permissible Operation Limit of Distributed Generation System in Distribution System)

  • 정원재;김태응;김재언
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2001년도 하계학술대회 논문집 A
    • /
    • pp.19-21
    • /
    • 2001
  • Nowadays, small scale DGS(Distributed Generation System), as a wind power generation or photovoltaic generation, becomes to be introduced into the power distribution system. But in that case it is difficult to properly maintain the terminal voltage of low voltage customers by using only LDC(Line Drop Compensator). So, it is necessary to determine the permissible operation limit of the introduced DGS for proper voltage in distribution system. In this paper clarifies the relationship between LDC voltage regulation principle and real, reactive power of DGS, and examines the permissible operation limit of the introduced DGS in distribution system which the voltage is controlled by LDC.

  • PDF

양양양수 온라인 무효전력 운전범위 시험과 과여자제한기(OEL) 동특성 시험 (On-line Tests of on the Yang-Yang Pumped Storage Plant for the Reactive Power Limits and the OEL Dynamics)

  • 김동준;문영환
    • 전기학회논문지
    • /
    • 제56권8호
    • /
    • pp.1343-1350
    • /
    • 2007
  • This paper describes the tests on the reactive power output limit and the Over-Excitation Limiter (OEL) dynamics of a generation unit. The suggested test methods on reactive limit can identify the allowable maximum/minimum reactive power at 100% rated MW in the steady-state unit operation condition. The on-line OEL test method can identify the time characteristics of OEL with the generation output at 50% of the rated MW. These methods are validated by applying to four Yang-Yang pumped storage units with 282 rated MVA each.

충돌회피를 위한 극한 운전시 자동차의 동적안정성 해석 (Dynamic Stability Analysis of A Vehicle in Limit Driving for Crash Avoidance)

  • 김성필;백운경
    • 동력기계공학회지
    • /
    • 제1권1호
    • /
    • pp.106-123
    • /
    • 1997
  • In this study, vehicle directional stability is investigated for limit driving for crash avoidance maneuver using a full vehicle dynamic model. The model was analytically validated using typical step steering and lane change simulation. Limit driving condition for the vehicle model was quoted from research results of references. It was demonstrated that instable vehicle motion was caused by not only road conditions but also driving conditions. Also, the simulation showed that braking combined with steering caused very hazardous situation in crash avoidance maneuver. Finally, phase plane plot approach was used to evaluate the dynamic instability.

  • PDF

원전 증기발생기 전열관 관막음 한계 고찰 (A Review of Plugging Limit for Steam Generator Tubes in Nuclear Power Plants)

  • 강용석;이국희
    • 한국압력기기공학회 논문집
    • /
    • 제16권2호
    • /
    • pp.10-17
    • /
    • 2020
  • Securing the integrity of steam generator tubes is an essential requirement for safe operation of nuclear power plants. Therefore, tubes that do not satisfy integrity requirements are no longer usable and must be repaired according to the related requirements. In general, the repair criterion is that the damage depth is more than 40% of the tube wall thickness. However, the plugging limit can be changed and be applied, provided a technical proof is given that integrity can be secured against specific degradation at a specific plants and that approval can be obtained from a regulatory agency. A typical example is alternative repair criteria for defects within the tube sheet or tube support plates. In this paper, a background of establishing the plugging limit for steam generator tubes and changes in maintenance criteria are reviewed as examples.