Power Maximization for a Multiport Network Described by the Admittance Matrix

Background: The original filter including grounded or virtual ground capacitors can be synthesized by using the NAM expansion. However, so far the filters including floating capacitor, such as Sallen-Key filter, have not been synthesized by means of the NAM expansion. This is a problem to be researched further. Methods: By using the adjoint network theory, the Sallen-Key filter including floating capacitor first is turned into a current-mode one, which includes a grounded capacitor and a virtual ground capacitor. Then the node admittance matrix, after derived, is extended by using NAM expansion. Results: At last, one VDTA Sallen-Key filter is received. It employs single compact VDTA and two grounded capacitors. Conclusion: A Butterworth VDTA second-order frequency filter based on Sallen-Key topology with fo = 100kHz, HLP = -HBP=1, is designed.

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Weighted Sum Power Maximization for Intelligent Reflecting Surface Aided SWIPT

IEEE Wireless Communications Letters ◽

10.1109/lwc.2019.2961656 ◽

2020 ◽

Vol 9 (5) ◽

pp. 586-590 ◽

Cited By ~ 32

Author(s):

Qingqing Wu ◽

Rui Zhang

Keyword(s):

Weighted Sum ◽

Power Maximization ◽

Reflecting Surface

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Analysis between graph-based and Power Transfer Distribution Factors (PTDF)-based model reduction methods in Electric Power Systems

International Journal of Emerging Electric Power Systems ◽

10.1515/ijeeps-2019-0278 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Diego A. Monroy-Ortiz ◽

Sergio A. Dorado-Rojas ◽

Eduardo Mojica-Nava ◽

Sergio Rivera

Keyword(s):

Power Systems ◽

Power System ◽

Model Reduction ◽

Electrical Power ◽

Schur Complement ◽

Power Transfer ◽

Electrical Power System ◽

Admittance Matrix ◽

Test Beds ◽

Power Transfer Distribution Factors

Abstract This article presents a comparison between two different methods to perform model reduction of an Electrical Power System (EPS). The first is the well-known Kron Reduction Method (KRM) that is used to remove the interior nodes (also known as internal, passive, or load nodes) of an EPS. This method computes the Schur complement of the primitive admittance matrix of an EPS to obtain a reduced model that preserves the information of the system as seen from to the generation nodes. Since the primitive admittance matrix is equivalent to the Laplacian of a graph that represents the interconnections between the nodes of an EPS, this procedure is also significant from the perspective of graph theory. On the other hand, the second procedure based on Power Transfer Distribution Factors (PTDF) uses approximations of DC power flows to define regions to be reduced within the system. In this study, both techniques were applied to obtain reduced-order models of two test beds: a 14-node IEEE system and the Colombian power system (1116 buses), in order to test scalability. In analyzing the reduction of the test beds, the characteristics of each method were classified and compiled in order to know its advantages depending on the type of application. Finally, it was found that the PTDF technique is more robust in terms of the definition of power transfer in congestion zones, while the KRM method may be more accurate.

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