• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 춘계학술대회 논문집 전력기술부문
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• pp.92-94
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• 2001

This paper investigated the real-time generator swing prediction by some researchers. And the first swing stability assessment based on EAC(Equal-Area Criterion) by using phasor measurement unit is proposed. Also we proposed the multi-swing prediction techniques, which is to estimate system parameters by using least square method / extrapolation with phasor measurement units. And the multi-swing prediction is performed with the estimated parameters. Future works are necessary to verify the proposed approaches in this paper.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 C
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• pp.1262-1266
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• 1999

More precise operation and control is required to ensure the stability and security of modern large power systems that is a complicated and widely dispersed structure. To ensure the precise operation and control of modern power system, most of all, precise monitoring and measurement of the various state values of power system is required. This paper discusses phasor measurement unit using synchronization signals from the GPS satellite system- Synchronized Phasor Measurement Unit. Considering the power system operation state, the transmitting data format over modems is defined. To provide all available information, PMU process the measurements to generate three phase symmetrical component. This paper proposes the transmitted data format and implements the PMU model using EMTP/Models. The validity of proposed model is confirmed through several contingency on the simple power system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 C
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• pp.1049-1053
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• 1999

It is important to measuring and monitoring about state vectors of power system for precise operation control. All state vectors cannot be measured because it is economically disadvantageous, so that some state vectors are determined using state estimator. Determination of observability is a important precondition of power system state estimation because state estimation can be performed when given power system is observable. Recently as time-synchronization technique progress, using the PMU(Phasor Measurement Unit), state vector can be measured directly so that voltage phasor and current phasor measurements can be used for power system estimation. In this paper, observability algorithm is proposed to determinate the observability with real/reactive injection power measurements and real/reactive lineflow power measurements of existing measurement system and with phasor measurements of PMU. The jacobian matrix is newly composed for state estimation with measurements of added PMU, and state estimation is performed with least square estimatior. Comparison between state estimation result of existing measurement system and that of measurement system added PMU is presented.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권1호
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• pp.53-76
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• 2020

The synchronous phasor measurement algorithm is the core content of the phasor measurement unit. This manuscript proposes a dynamic synchronous phasor measurement algorithm based on compressed sensing theory. First, a dynamic signal model based on the Taylor series was established. The dynamic power signal was preprocessed using a least mean square error adaptive filter to eliminate interference from noise and harmonic components. A Chirplet overcomplete dictionary was then designed to realize a sparse representation. A reduction of the signal dimension was next achieved using a Gaussian observation matrix. Finally, the improved orthogonal matching pursuit algorithm was used to realize the sparse decomposition of the signal to be detected, the amplitude and phase of the original power signal were estimated according to the best matching atomic parameters, and the total vector error index was used for an error evaluation. Chroma 61511 was used for the output of various signals, the simulation results of which show that the proposed algorithm cannot only effectively filter out interference signals, it also achieves a better dynamic response performance and stability compared with a traditional DFT algorithm and the improved DFT synchronous phasor measurement algorithm, and the phasor measurement accuracy of the signal is greatly improved. In practical applications, the hardware costs of the system can be further reduced.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.173-174
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• 2006

The power infrastructure defense system monitor and control a power system with parameters of a power system such as voltage, phasor angle, frequency and power flow which are measured at the same instance. For this, synchronized phasor measurement based on the GPS(Global Positioning System) is necessary. PMU(Phasor Measurement Unit) measures synchrophasor and transmits it to the power infrastructure defense system. For this communication, IEEE H37.118 defines a communication message format and measurement concept and we extend the protocol to transmit disturbance data. The synchrophasor data can be sent at various rates and there are several options for phasor information sent in the synchrophasor message. In this paper, we develop software that simulate communication between the power infrastructure defense system and PMU to annalize the traffic.

• Journal of Electrical Engineering and Technology
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• 제12권3호
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• pp.996-1006
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• 2017

Phasor Measurement Unit (PMU) placement is a crucial problem for State Estimation (SE) of the power system, which can ensure that the power network is fully observed. Further, the observation reliability problem of the system has been concerned in the operation conditions. In this paper, based on modified weighted adjacent matrix ($A_w$), an optimal placement method is proposed to solve simultaneously two problems involving the optimal PMU placement problem and the observation reliability enhancement problem of the system. The purpose of the proposed method is to achieve both the minimum total cost and the maximum observation reliability, with a focus on increasing the security of observability, strengthening the observation reliability of buses as well as enhancing the effectiveness of redundancy. Simulations on IEEE 14, 24, 30 and 57 bus test systems are presented to justify the methodology. The results of this study show that the proposed method is not only ensuring the power network having the observability effectively but also enhancing significantly the observation reliability. Therefore, it can be a useful tool for SE of the power system.

• International Journal of Computer Science & Network Security
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• 제23권3호
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• pp.130-138
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• 2023

The Smart grids are considered as multi-disciplinary power systems where the communication networks are highly employed. This paper presents optimal wide area measurement system (WAMS) configuration in Nordic power system. The transition from SCADA to WAMS becomes now trend in all power systems to ensure higher reliability and data visibility. The optimization applied in this research considered the geographical regions of the Nordic power system. The research considered all the devices of WAMS namely phasor measurement units (PMUs), phasor data concentrators (PDCs) and communication links. The study also presents two scenarios for optimal WAMS namely base case and N-1 contingency as different operating conditions. The result of this research presents technical and financial results for WAMS configuration in a real power system. The optimization results are performed using MATLAB 2017a software application.

• 대한전기학회논문지:시스템및제어부문D
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• 제50권12호
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• pp.584-589
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• 2001

This paper presents an implementation method of multi-channel synchronized phasor measurement device, which is based on the ASIC implementation of the sliding-DFT. A time-shared multiplier structure is proposed to minimize the number of gates required for the implementation. The design is verified by the timing simulation of its operation. The effect of coefficient approximation in the recursive implementation of the sliding-DFT is analytically derived and verified with the computer simulations.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.342-344
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• 2002

This paper presents a new strategy to find starting points for placing optimally Phasor Measurement Units(PMUs). The performance of the starting point, initial placement set of PMUs, affect critically the computational burden and/or time, because the Optimal PMU Placement (OPP) problem is formulated the combinatorial optimization. By analyzing the properties of OPP solutions on IEEE sample systems in detail, a new strategy for initial PMU placement, in this paper, is proposed. To verify the performance of the suggested strategy, the comparison with the existing strategy and the new one, on IEEE sample systems. is performed. By using the new strategy, the numbers of search spaces to solve the OPP problem is drastically decreased.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 A
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• pp.193-195
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• 2003

This paper presents an approach to estimate the power transmission line parameter by phasor measurement units(PMUs), which are synchronized to 1 pps signal of GPS. Existing approaches to estimate power transmission line parameter, are mainly off-line ones, based on faults or switching events on other neighboring lines. In this paper, to obtain static and dynamic properties of power transmission line parameter in service, the prototype of pmu-based Transmission Line Parameter Monitoring System (TLPMS) is proposed. Also, an technique to estimate parameters of transmission line described as 2-port network model and the soundness of estimated parameters are addressed.