• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.181-183
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• 2002

Complete load model of the substation not only should include the performances of the load components, but also should take into consideration the core losses of transformers, the line losses and the capacitor banks. In an actual distribution system, the control scheme of capacitor banks are so complex and is difficult to identify actual values for the reactive powers of capacitor banks. This research improves on this drawback by applying component-based modeling method including a capacitor banks in distribution systems. Initial differences between the model results and the actual values for reactive powers are later decreased by the proposed method.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제52권9호
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• pp.448-453
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• 2003

In this paper the controlled closing algorithm of the circuit breaker for isolated capacitor banks is proposed. The characteristics of circuit breakers such as RDDS(rate of decrease of dielectric strength) and a mechanical operating tolerance should be also taken into account to locate contact touch instants around voltage zero. The analysis results on the voltages across circuit breaker terminals upon closing operation play an important roles to describe the suggested method. The simulations carried out in order to verify the performance of this method show that the closing instants obtained from the proposed method provide a good suppression effect on the closing transients for both single and back-to-back capacitor banks.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 A
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• pp.233-235
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• 2000

SVC(Static Var Compensator) is commonly installed with conventional mechanically switched existing reactor or capacitor banks for wide range voltage control. The frequencies of switching of external banks have a great impact on the quality of voltage, but is limited since the life time of the external banks depends severely on the number of switching. So it is a complete multi-objective nonlinear optimization problem with conflicting objectives. This paper presents a method to determine the optimal coordination of SVC and external banks using genetic algorithm based on the multi-objective criteria. Optimal dead band and delay time of external banks is sought for reliable and efficient operation

• 대한전기학회논문지:전력기술부문A
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• 제52권3호
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• pp.179-182
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• 2003

Component-based method for load model not only should include the performances of the load components, but also should take into consideration the core losses of transformers, the line losses and the capacitor banks. Especially, capacitor bank affects the accuracy of reactive load model in load modeling. But it is difficult to identify actual reactive powers of capacitor banks in power system for load modeling. This research improves the component-based modeling method including uncertain capacitor bank. The proposed method is hybrid technique, which adds the measurement-based method to the existing component-based method for reliable information of capacitor band. The results of case studies were presented to verify the validity of the proposed method.

• 조명전기설비학회논문지
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• 제22권8호
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• pp.12-17
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• 2008

대부분의 수용가 부하와 전력 설비는 근본적으로 유도성이고 지상 역률로 운영되고 있다. 수용가에 캐패시터 뱅크를 적용하면 역률 개선과 무효전력 공급, 전압 상승, 전력 손실 저감과 전기요금 저감 등 많은 혜택이 있다. 또한 캐패시터 뱅크를 설치하면 고조파와 같은 전력 품질에 문제를 야기시킬 수 있다. 본 논문에서는 수용가에 설치된 캐패시터 뱅크의 역률 개선 및 고조파 저감을 심도 있게 분석한다. 사례연구 시스템은 EDSA 프로그램으로 시뮬레이션하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부A
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• pp.329-331
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• 1998

This paper presents a modified Learning Vector Quantization rule to control shunt capacitor banks and feeder voltage regulators in electric distribution systems with Kohonen Neural Network(KNN). The objective of the KNN is on-line decision of the optimal state of shunt capacitor banks and feeder voltage regulators which minimize $I^{2}R$ losses of the distribution system while maintaining all the bus voltages within the limits. The KNN is tested on a distribution system with 30 buses, 5 on-off switchable capacitor banks and a nine tap line voltage regulator.

• 대한전기학회논문지:전력기술부문A
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• 제54권2호
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• pp.61-66
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• 2005

This paper presents a refined protection algorithm of the unfused 22.9kV shunt capacitor banks in grounded wye connection to improve the existing algorithm using the voltage difference method. It is difficult to detect ground faults with arc near the input points or ground faults near the grounding point by the existing algorithm using only the voltage balanced relay. This paper shows that ground faults with arc near the input point can be detected by harmonics analysis of the differential voltage and that it has no impact of harmonics out of nonlinear loads which have the quantitative influence on capacitor banks. Thus the proposed method using harmonics analysis can be a proper detection method. In case of ground faults near the grounding point, an OVGR is being added recently and its validity is verified in this paper. The proposed method is applied to a 22.9kV example system and is verified that the proposed algorithm can detect clearly faults which are not easy to detect by the existing method.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2003년도 춘계전력전자학술대회 논문집(1)
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• pp.182-185
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• 2003

Proposed Hybrid System is composed of phase leading capacitor banks, LC passive filters and active power filter. The passive power filter in parallel connection eliminate the 5th and 7th harmonics. The Variable capacitor banks correct the most of power factor, and the active power filter takes charge of remainder,

• 전기학회논문지
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• 제57권4호
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• pp.543-550
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• 2008

This paper proposes an voltage and reactive power control methodology, which is motivated towards implementation in the korea power system. The main voltage control devices are capacitor banks, reactor banks and LTC transformers. Effects of control devices are evaluated by local subsystem's cost computations. This local subsystem is decided by 'Tier' and 'Electrical distance' in the whole system. The control objective at present is to keep the voltage profile within constraints with minimum switching cost. A robust control strategy is proposed to make the control feasible and optimal for a set of power-flow cases that may occur important event from system. This studies conducted for IEEE 39-bus low and high voltage contingency cases indicate that the proposed control methodology is much more effective than PSS/E simulation tool in deciding switching of capacitor and reactor banks.

• 조명전기설비학회논문지
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• 제17권5호
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• pp.51-59
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• 2003

전력회사와 수용가들은 유도성 부하에 무효전력을 공급하여 역률(수용가)이나 전압(전력회사)을 조절하기 위해 커패시터 뱅크(전력회사는 스타콘이라 함)를 설치 운영하고 있다. 본 논문에서는 전력회사의 스타콘 투입시 발생되는 과도 전압 상승과 고조파를 분석하고자 한다. 과도 전압과 고조파를 저감시키는 간단한 수단중의 하나는 수용가의 커패시터 뱅크를 전력회사의 스타콘을 투입한 후에 과도상태가 지난뒤에 투입하는 방법이다. EDSA프로그램으로 컴퓨터 시뮬레이션을 수행하여 수용가에서의 과도 전압 상승과 고조파 저감 효과를 검증 하였다. 그리고 수용가에서 발생하는 고조파를 잘 알려진 국제 고조파 관리 기준인 IEEE 519와 IEC 1000으로 비교해 보았다.