• Title/Summary/Keyword: power normalization

Search Result 105, Processing Time 0.032 seconds

KPX's EMS Network Analysis Operation Status in Korea Power System (KPX의 한국 전력 계통에서 EMS 계통해석기능 활용실태 소개)

  • Kang, Hyung-Koo;Han, Hee-Cheon
    • Proceedings of the KIEE Conference
    • /
    • 2005.11b
    • /
    • pp.30-34
    • /
    • 2005
  • Due to old Toshiba EMS's database size limit and hardware old aging, KPX(Korea Power Exchange) had introduced New EMS from AREVA(old ALSTOM) in July 2002. After then KPX had committed many man power and time to normalize EMS NA(Network Analysis) functions for using real power system. At initial stage, to normalize State Estimator which is the backbone of all other NA functions and DTS(Dispatcher Training Simulator}, KPX had corrected numerous topology errors, network model errors, non-scanned and wrongly scanned SCADA measured errors. After SE function study, running test and tuning, State Estimator could finally have been run properly and stably from June 2003. Based on SE running, KPX had normalized real time Contingency Analysis, and study mode Power Flow, STNET and DTS. From early 2004, dispatchers have been trained to use NA and DTS for the purpose of stable SE running, NA operation & results reading and urgent equipment outage reviewing. EMS NA have been greatly contributed to operate real time power system stably. Above NA normal operation by KPX own efforts under the no experience of NA running, KPX made a good precedent. This paper is intended to introduce EMS NA normalization process, operation status, and etc in Korea power system operation.

  • PDF

A Study on Convergence Security of Power Generation Control System (발전 제어시스템의 융합보안 연구)

  • Lee, Daesung
    • Convergence Security Journal
    • /
    • v.18 no.5_1
    • /
    • pp.93-98
    • /
    • 2018
  • Korea Hydro & Nuclear Power Co., Ltd., Korea Electric Power Corporation, and Korea South-East Power Corporation are major infrastructure facilities of power supplying countries. If a malicious hacking attack occurs, the damage is beyond the imagination. In fact, Korea Hydro & Nuclear Power has been subjected to a hacking attack, causing internal information to leak and causing social big problems. In this paper, we propose a strategy and countermeasures for stabilization of various power generation control systems by analyzing the environment and the current status of power generation control system for convergence security research, which is becoming a hot issue. We propose a method to normalize and integrate data types from various physical security systems (facilities), IT security systems, access control systems, to control the whole system through convergence authentication, and to detect risks through fusion control.

  • PDF

A note on Box-Cox transformation and application in microarray data

  • Rahman, Mezbahur;Lee, Nam-Yong
    • Journal of the Korean Data and Information Science Society
    • /
    • v.22 no.5
    • /
    • pp.967-976
    • /
    • 2011
  • The Box-Cox transformation is a well known family of power transformations that brings a set of data into agreement with the normality assumption of the residuals and hence the response variable of a postulated model in regression analysis. Normalization (studentization) of the regressors is a common practice in analyzing microarray data. Here, we implement Box-Cox transformation in normalizing regressors in microarray data. Pridictabilty of the model can be improved using data transformation compared to studentization.

A Real-Time Method for the Diagnosis of Multiple Switch Faults in NPC Inverters Based on Output Currents Analysis

  • Abadi, Mohsen Bandar;Mendes, Andre M.S.;Cruz, Sergio M.A.
    • Journal of Power Electronics
    • /
    • v.16 no.4
    • /
    • pp.1415-1425
    • /
    • 2016
  • This paper presents a new approach for fault diagnosis in three-level neutral point clamped inverters. The proposed method is based on the average values of the positive and negative parts of normalized output currents. This method is capable of detecting and locating multiple open-circuit faults in the controlled power switches of converters in half of a fundamental period of those currents. The implementation of this diagnostic approach only requires two output currents of the inverter. Therefore, no additional sensors are needed other than the ones already used by the control system of a drive based on this type of converter. Moreover, through the normalization of currents, the diagnosis is independent of the load level of the converter. The performance and effectiveness of the proposed diagnostic technique are validated by experimental results obtained under steady-state and transient conditions.

A Study for the Effect on the Uncertainty of Power Performance Testing of Windturbine by a Site Calibration (Site calibration이 풍력발전시스템 성능시험 불확도에 미치는 영향 연구)

  • Kim, Keon-Hoon;Hyun, Seung-Gun
    • Journal of the Korean Solar Energy Society
    • /
    • v.31 no.2
    • /
    • pp.107-112
    • /
    • 2011
  • A comparison study between two performance testing results, one is on the site calibration not needed and the other is needed, was proceeded for the understanding on the effect of site calibration on the complex terrain. As a result, it is revealed that all of uncertainty components is effected by the topographical features dramatically. And the maximum difference of uncertainty reached at around 8% of rated capacity of wind turbine. So, the site calibration is an effective method to remove the variable wind effect by the ground complexity and must be proceeded before the power performance testing of a wind turbine.

Development of an Adaptive Neuro-Fuzzy Techniques based PD-Model for the Insulation Condition Monitoring and Diagnosis

  • Kim, Y.J.;Lim, J.S.;Park, D.H.;Cho, K.B.
    • Electrical & Electronic Materials
    • /
    • v.11 no.11
    • /
    • pp.1-8
    • /
    • 1998
  • This paper presents an arificial neuro-fuzzy technique based prtial discharge (PD) pattern classifier to power system application. This may require a complicated analysis method employ -ing an experts system due to very complex progressing discharge form under exter-nal stress. After referring briefly to the developments of artificical neural network based PD measurements, the paper outlines how the introduction of new emerging technology has resulted in the design of a number of PD diagnostic systems for practical applicaton of residual lifetime prediction. The appropriate PD data base structure and selection of learning data size of PD pattern based on fractal dimentsional and 3-D PD-normalization, extraction of relevant characteristic fea-ture of PD recognition are discussed. Some practical aspects encountered with unknown stress in the neuro-fuzzy techniques based real time PD recognition are also addressed.

  • PDF

A Study on the Process of Normalizing Children in Montessori's Education (몬테소리교육(敎育)에서 아동(兒童)의 정상화과정(正常化過程)에 관한 고찰(考察))

  • Hwaug, Ok Ja
    • Korean Journal of Child Studies
    • /
    • v.5
    • /
    • pp.107-119
    • /
    • 1984
  • In this article we reviewed the phenomena and processes of normalizing children through documentary records with interest in the aim of Montessori's education methods. The Montessori education method is based on the theory that all children should be respected and their works prized. The normalization of children does not mean only to turn abnormal children into normal ones, but to make normal characteristics - calmness, self-confidence, happiness or patience, etc.- which are latent in themselves, appear on the surface and remold them as new children. To achieve normalization some prerequisites are necessary. They are as follows: 1) The principle of freedom. The freedom in Montessori's education has some limits in prepared environments suitable for developing children as whole persons through their spontaneous activities. 2) Development of the phenomenon of children's attention. Arousal of their attention in the children's primitive inner impulse and sense of spiritual hunger. To satisfy their hunger children divert their interest to certain objects and come to repeated exercise of intelligence. 3) Concentration and repetitive phenomena. Repetition through children's concentration phenomenon is a natural and important fundamental behavior which controls their mental power. Repetitive behavior will form serious discipline and promote development of their intelligence.

  • PDF

Experiments on Extraction of Non-Parametric Warping Functions for Speaker Normalization (화자 정규화를 위한 비정형 워핑함수 도출에 관한 실험)

  • Shin, Ok-Keun
    • The Journal of the Acoustical Society of Korea
    • /
    • v.24 no.5
    • /
    • pp.255-261
    • /
    • 2005
  • In this paper. experiments are conducted to extract a set of non-Parametric warping functions to examine the characteristics of the warping among speakers' utterances. For this Purpose. we made use of MFCC and LP spectra of vowels in choosing reference spectrum of each vowel as well as representative spectra of each speaker. These spectra are compared by DTW to give the warping functions of each speaker. The set of warping functions are then defined by clustering the warping functions of all the speakers. Noting that male and female warping functions have shapes similar to Piecewise linear function and Power function respectively, a new hybrid set of warping functions is defined. The effectiveness of the extracted warping functions are evaluated by conducting phone level recognition experiments, and improvements in accuracy rate are observed in both warping functions.

Normalization Effect of Both ST36 and CV11, 12, 13 Meridian Points on the Abnormal Gastric Myoelectrical Activity in Two Cases of Functional Dyspeptic Patients (족삼리와 상완, 중완, 하완혈의 침 자극으로 기능성 소화불량증 환자의 위 평활근 전기적 활성 장애를 정상화시켰던 증례 2례)

  • Yoon, Sang-Hyub
    • The Journal of Internal Korean Medicine
    • /
    • v.42 no.4
    • /
    • pp.707-717
    • /
    • 2021
  • Objectives: The aim of this study was to introduce the normalization effects of stimulation of both ST36 and CV11, 12, 13 meridian points on the abnormal gastric myoelectrical activity in two cases of functional dyspeptic patients with gastric dysmotility. Methods: Gastric myoelectrical activity was recorded by electrogastrography every two weeks until their gastric myoelectrical activity finally reached the normality. Dominant frequency of gastric slow waves in the fasting and postprandial periods and a dominant power ratio were obtained on each occasion. Patients were treated three times each day: 9 am, 1 pm, and 7 pm. The first treatment consisted of manual and immersion stimulation on all used meridian points for 20 min. In the second and third treatments, electrical stimulation of both ST36 was added. It was conducted for 20 min at a strength intensity of 1.2 times the pain threshold at a frequency of 3 Hz. Results: Stimulation of the above meridian points normalized abnormal gastric myoelectrical activity. The time taken to return from abnormal gastric myoelectrical activity to normal was 16-19 weeks. Conclusion: Stimulation of both ST36 and CV11, 12, 13 meridian points normalized the abnormal gastric myoelectrical activity in the functional dyspepsia of gastric dysmotility.

Research on prediction and analysis of supercritical water heat transfer coefficient based on support vector machine

  • Ma Dongliang;Li Yi;Zhou Tao;Huang Yanping
    • Nuclear Engineering and Technology
    • /
    • v.55 no.11
    • /
    • pp.4102-4111
    • /
    • 2023
  • In order to better perform thermal hydraulic calculation and analysis of supercritical water reactor, based on the experimental data of supercritical water, the model training and predictive analysis of the heat transfer coefficient of supercritical water were carried out by using the support vector machine (SVM) algorithm. The changes in the prediction accuracy of the supercritical water heat transfer coefficient are analyzed by the changes of the regularization penalty parameter C, the slack variable epsilon and the Gaussian kernel function parameter gamma. The predicted value of the SVM model obtained after parameter optimization and the actual experimental test data are analyzed for data verification. The research results show that: the normalization of the data has a great influence on the prediction results. The slack variable has a relatively small influence on the accuracy change range of the predicted heat transfer coefficient. The change of gamma has the greatest impact on the accuracy of the heat transfer coefficient. Compared with the calculation results of traditional empirical formula methods, the trained algorithm model using SVM has smaller average error and standard deviations. Using the SVM trained algorithm model, the heat transfer coefficient of supercritical water can be effectively predicted and analyzed.