• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.62.4-62
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• 2002

$\textbullet$ Contents 1. Introduction $\textbullet$ Contents 2. System Description $\textbullet$ Contents 3. Decoupled Sliding Mde Control $\textbullet$ Contents 4. Decoupled Adaptive Fuzzy Sliding Mode Control through width adaptation $\textbullet$ Contents 5. Simulation Result $\textbullet$ Contents 6. Conclusion

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.5
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• pp.403-408
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• 2012

In this paper, we propose useful load flow algorithms called FEDL (fast enhanced decoupled load flow). The proposed load flow method can improve the convergence characteristics particularly when the P-Q coupling becomes significant and the power system operating states deviate from the conditions required for stable convergence of the FDL by reflecting in part the effects of the off-diagonal terms in the Jacobian. In our test with IEEE AEP-30 bus system and RTS-96 73-bus system, it converge even when the fast decoupled load flow (FDL) and its variations keeping load flow matrices constant experience convergence problems. Test results show promising performances of the proposed algorithms in their convergence characteristics both in number of iterations and overall convergence speeds.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.49 no.8
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• pp.467-472
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• 2000

A three-level decoupled sliding mode controller is developed to achieve asymptotic stability for a class of sixth-order nonlinear systems. The sixth-order system is decoupled into three subsystems according to the structure of the whole system. Each subsystem has a separate control target in the form of a sliding surface. The information of the third sliding surface is transferred to the second one through an intermediate variable and the information of the second sliding surface is transferred to the first one through another intermediate variable. Consequently, the controller designed on the basis of the first sliding surface can make three subsystems move toward their sliding surfaces, respectively. The three-level decoupled sliding mode controller is applied to the double-inverted pendulum problem where the zero stable states are required.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10c
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• pp.175-177
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• 2004

무선망에서의 TCP 성능은 않은 연구가 되어 왔지만 손실율이 큰 경우의 TCP의 성능은 아직도 개선의 여지가 많다. 본 논문은 두 가지 점에서 새로운 TCP를 제안한다. 첫째, 혼잡제어(Congestion Control)와 손실제어(Loss Recovery)가 분리(Decoupled)되었다. 기존의 연구들은 무선손실과 혼잡손실을 구분하여야 한다는 점에는 많은 연구를 해왔지만 무선 손실에 대하여 어떻게 대처할 것 인가에 관한 문제는 상대적으로 간과하였다. 둘째, 기종의 TCP-Westwood와 TCP-Jersey에서 사용되는 ABE(Available Bandwidth Estimation)가 무선네트워크에 의해 발생하는 패킷 손실로 인해 부정확해지는 것을 지적하고 새로운 ABE방법을 제시한다. 시뮬레이션을 통하여 우수한 성능을 보여주었다.

• Journal of Power System Engineering
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• v.6 no.3
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• pp.64-70
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• 2002

A fast decoupled algorithm for time domain simulation of power electronics circuits is presented. The circuits can be arbitrarily configured and can incorporate feedback amplifier circuits. This simulation algorithm is performed for the input series output parallel connected 2 switch forward converter. Steady state and large signal transient responses due to a step load change are simulated. The simulation results are verified through experiments.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.34 no.5
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• pp.201-209
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• 1985

This paper describes a method for the state estimation by a modified fast decoupled estimation method and system decomposition. The state values are gained by using the weighted least square estimation method, fast decoupled estimation method, and modified fast decoupled estimation method. The estimated values of each method were compared about effectiveness of state values, respectively. This paper investigated the effects of impedance of well-condition or ill-condition into lines. The characteristics of state estimation were gained through hierarchical state estimation. Each method was applied to three model power systems, and, the results of test for the proposed method are given.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.12
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• pp.1514-1519
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• 1999

This paper presents two flexible alternatives to the decoupled load flow(DCL) method. The proposed load flow methods can improve the convergence profiles of the DCL by reflecting in part the effects of the off-diagonal terms in the Jacobian at minimal costs. They can improve the convergence characteristics especially when the power system operating states deviate from the conditions required for stable convergence of the DCL and the P-Q coupling becomes significant. Two algorithms are obtained from the expression of the full Newton-Raphson load flow (NRL) method by successively diminishing the effects of the off-diagonal submatrices in the Jacobian. In the process of simplification, the Neuman series expansion is utilized. Test results show promising performances of the proposed algorithms in their convergence characteristics both in number of iterations and overall convergence speeds. Proposed algorithms are expected to provide flexible alternatives to the NRL when the DCL experiences convergence problems.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.46-48
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• 2000

Continuation power flow has been developed to remove the ill-condition problem caused by singularity of power flow Jacobian at and near steady-state voltage instability point in conventional power flow. When solving large-scale power transmission systems, an alternative strategy for improving computational efficiency and reducing computer storage requirements is the decoupled power flow method, which makes use of an approximate version of the Newton-Raphson procedure. This paper presents a technique to improve the speed of continuation power flow system using decoupled power flow method.

• Proceedings of the KIEE Conference
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• 1999.11b
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• pp.248-250
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• 1999

본 논문에서 제안된 조류계산 알고리즘은 Jacobian의 off-diagonal 부 행렬을 완전히 무시하는 Decoupled Load Flow(DCL) 알고리즘들의 유연한 대안으로 반복(iteration)당 최소한의 추가 계산 부담으로 Jacobian의 off-diagonal 부분의 효과를 부분적으로 반영함에 의해 수렴 특성을 향상시킬 수 있다. 제안된 방법들은 특히 Fast Decoupled Load Flow(FDL)로 대표되는 DCL들의 수렴특성이 불안정해질 경우, 효과적으로 수렴특성을 향상시킬 수 있다. 제안된 알고리즘들은 Newton-Raphson Load Flow(NRL) 방법에서 Jacobian의 off-diagonal 부분의 효과를 점진적으로 제거하는 방법으로 유도하였고, 간략화 과정에서는 Neuman series expansion을 사용하였다. 실험결과 제안된 알고리즘들은 반복횟수와 전반적인 수렴 속도에서 확실한 성능향상을 보여주었다. 제안된 알고리즘들은 특히 DCL의 수렴성능이 문제가 있을 시 full NRL 대신에 적용할 수 있는 가능성이 있어 조류계산 시간을 단축해 줄 수 있을 것으로 기대된다.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.21 no.1
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• pp.23-29
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• 2013

This paper presents a tracking filter of radar beacon system (RBS) for automatic takeoff and landing of an unmanned aerial vehicle. The proposed tracking filter is designed as the decoupled tracking filter to reduce the computational burden. Also, an adaptive estimation method of the measurement error covariance is proposed to provide an improved tracking performance compared to the conventional decoupled tracking filter whenever the accuracy of RBS observations is degraded. 100 times Monte Carlo runs performed to analyze the performance of the proposed tracking filter in case of normal operation and degraded operations, respectively. The simulation results show that the proposed tracking filter provides the improved tracking accuracy in comparison with the conventional decoupled tracking filter.