• 전기학회논문지
• /
• 제65권11호
• /
• pp.1913-1918
• /
• 2016

In order to analyze the power consumption pattern of the DC urban rail system, the method to obtain a solution establishing the current equation according to fixed position of the substation and varying position of the train is used. The proposed analysis method using the network analysis is to model the transfer function of the component constituting a direct current power supply system (dc substation, train, catenary) to the voltage and current. By multiplying the model formula consecutive, it can calculate the voltage and current of each element of power supply circuit and shows a simple case analysis.

• 대한전기학회논문지:전력기술부문A
• /
• 제51권8호
• /
• pp.385-390
• /
• 2002

This paper presents a substation expansion planning method with quantitative analysis using ANP. To calculate the reliability factor and economy factor of the system, reliability indices and total construction cost is used. With these factors, new ANP model which select the best plan either economy or reliability among various alternatives is developed. This model can assist the decision making for the system planner. The usefulness of the method is verified by applying it to the large-scaled distribution system.

• 전기학회논문지P
• /
• 제56권1호
• /
• pp.56-62
• /
• 2007

In this paper, design method for power tower hazard diagnosis/predition system based on UsN was proposed. The proposed method used multi-hybrid sensors to measure rotation, displacement, and inclination state of power tower, and made decision/prediction of hazard of power tower. System design was made with requirement analysis of monitoring for transmission power facility and use of MEMS and optic fiber sensors. For hazard decision, analysis of correlation was made using sensor output. LN based on IEC61850,international standard for digital substation, was also proposed. For transmission facility monitoring, digital substation and power tower were considered as parts of power facility networks.

• 전기학회논문지
• /
• 제60권4호
• /
• pp.892-898
• /
• 2011

In DC electric railways, while an electric rail car is driving, a part of the working current returned to the substation through rails leaks into the ground. Such a stray current causes railway facilities and metal objects to corrode electrolytically. Therefore, change of stray current needs to be monitored constantly. But so far in domestic, the research on stray current measuring techniques and system adaption are insufficient. To estimate stray current, this paper addresses a method of monitoring the return current that is returned into the negative pole of the substation in real time.

• 전기학회논문지
• /
• 제61권7호
• /
• pp.950-956
• /
• 2012

As development of battery technologies, the installation of Battery Energy Storage System (BESS) increased. The BESS can be used for various purposes such like frequency response, load leveling, and fluctuation mitigation of renewable energy generators. In this paper, three state BESS model is proposed. the BESS model considering charge, discharge and keeping efficiency, and life cycle according to depth of discharge (DOD). Then, the benefit and cost of BESS installed at substation for load leveling are summarized. The economic evaluation of BESS is analyzed using net present values (NPV) analysis. In case study, the NPV analysis of NaS battery system is carried out using the proposed BESS model. Because the result of economic evaluation of BESS using nowadays cost data is not positive, the sensitivity analysis of BESS is conducted by changing the capital cost and energy cost.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1997년도 하계학술대회 논문집 D
• /
• pp.761-763
• /
• 1997

As the power system network is enlarged and complicated gradually, the automation of power system network is essential to enhance the reliability and performance of the operation of power system. Distribution restoration is a major part of the automation. This paper proposes a new distribution restoration system to restore healthy blackout regions by the hierarchical cooperation with the substation automation systems. In proposed system, the range of restoration is extended to substations and the performance as well as the switching efficiency of restoration system is enhanced.

• 조명전기설비학회논문지
• /
• 제23권10호
• /
• pp.75-80
• /
• 2009

IED가 GOOSE를 통해 전달하는 메시지가 일반적으로 변전소의 보호와 제어를 담당하는 중요하고 민감한 신호이다 보니 네트워크의 이상 상황으로 인한 통신패킷의 손실과 전송속도 저하 등에 대처하기 위한 네트워크 이중화(Redundancy)를 고려하고 있다. 이를 위해 네트워크 토폴로지의 이중화와 함께 IED도 네트워크 포트를 2개로 구현하여 스위치방식에 의한 이중화를 지원하고 있다. IEC 61850 GOOSE 적합성 시험은 IED 통신서비스 기능시험에 국한하기 때문에 본 논문에서는 변전자동화시스템의 네트워크 이중화를 고려한 IED의 스위치 이중화 장치의 GOOSE 전송 성능을 시험할 수 있는 방법을 제시하고 실계통에 적용중인 IED의 사례 검증을 통해 네트워크 이중화를 고려한 IED의 GOOSE 전송이 변전자동화시스템에 어떤 영향을 주는지 분석하고자 한다.

• 전기학회논문지
• /
• 제63권2호
• /
• pp.224-229
• /
• 2014

This paper presents the novel voltage control method in power distribution system with distributed generators. The voltage in distribution systems is regulated by Under Load Tap Changer(ULTC) of substation and pole transformer of primary feeders. Recently, Step Voltage Regulator(SVR) is getting located at distribution feeders to regulate effectively voltage of primary feeders. But the effectiveness of SVR decreases due to independent operation between SVR and ULTC, and also the existing Line Drop Compensator(LDC) method considering the distributed generators may be not able to regulate the proper voltage in a permissible range. Thus, this paper presents a optimal voltage control algorithm of SVR by using the secondary voltage data of main transformer in substation.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2007년도 춘계학술대회 논문집 전기설비전문위원
• /
• pp.152-154
• /
• 2007

This paper represents the criteria of earthing system for substation design in Korea. The construction of new substations and expansion of existing facilities are commonplace projects in KEPCO(Korea Electric Power Corporation). The KEPCO has had the only design criteria, which need to be adequate criteria considering the new technology and environment in Korea.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 하계학술대회 논문집 A
• /
• pp.406-408
• /
• 2004

It is very necessary to adopt bad data processing in order to maintain the security and the reliability of data acquisition and management in the substation. This paper presents a bad data processing method of per module unit by using rule based system. The propriety of this method has been verified by the case study