Topology (electrical circuits)

About: Topology (electrical circuits) is a research topic. Over the lifetime, 33316 publications have been published within this topic receiving 397651 citations. The topic is also known as: topology.

A family of high power density unregulated bus converters

Abstract: This paper begins by reviewing current bus converters and exploring their limitations. Next, a family of inductor-less bus converters is proposed to overcome the limitations. In the new bus converters, magnetizing current is used to achieve zero-voltage-switching (ZVS) turn-on for all switches. The resonant concept is used to achieve nearly zero-current-switching (ZCS) turn-off for the primary switches and no body diode loss for the synchronous rectifiers (SRs). Meanwhile, the self-driven method can be easily applied to save drive loss of SRs. Based on these concepts, a full-bridge bus converter is built in the quarter-brick size to verify the analysis. The experimental results indicate that it can achieve 95.5% efficiency at 500-W, 12-V/45-A output. Compared with industry products, this topology can dramatically increase the power density. These concepts are also applied to nonisolated dc/dc converters. As an example, a resonant Buck converter is proposed and experimentally demonstrated.

Comparison of Cascaded H-Bridge and Modular Multilevel Converters for BESS application

Abstract: This paper compares the Cascaded H-Bridge (CHB) converter topology with the Modular Multilevel Converter topology (M2LC) for the use in battery energy storage systems (BESS). Standard modules are examined as well as extended modules allowing an increase in output voltage. Semiconductor and capacitor requirements are evaluated by simulation, and practical considerations are discussed. Experimental results from a laboratory setup of a CHB based BESS are presented.

Topology identification of weighted complex dynamical networks

Abstract: Recently, various papers investigated the geometry features, synchronization and control of complex network provided with certain topology. While, the exact topology of a network is sometimes unknown or uncertain. Using Lyapunov theory, we propose an adaptive feedback controlling method to identify the exact topology of a rather general weighted complex dynamical network model. By receiving the network nodes evolution, the topology of such kind of network with identical or different nodes, or even with switching topology can be monitored. Experiments show that the methods presented in this paper are of high accuracy with good performance.

Fully decoupled current control and energy balancing of the Modular Multilevel Matrix Converter

Abstract: The Modular Multilevel Matrix Converter (M3C) is a Modular Multilevel Converter topology which is suitable for high power low speed drive applications. This paper presents a fully decoupled current control which allows an independent input, output and internal balancing current control. To equalize the energy stored in the nine converter arms, an energy and balancing control is presented which includes average, horizontal, vertical and diagonal balancing control loops. Simulation results are used to verify the function of the M3C together with an induction motor drive system. Additionally, the proper function of the recently constructed arm PCB working as single phase multilevel STATCOM is presented. This PCB will be used for each arm in the laboratory prototype of the M3C in the near future.

Topology Discovery in Software Defined Networks: Threats, Taxonomy, and State-of-the-Art

Abstract: The fundamental role of the software defined networks (SDNs) is to decouple the data plane from the control plane, thus providing a logically centralized visibility of the entire network to the controller. This enables the applications to innovate through network programmability. To establish a centralized visibility, a controller is required to discover a network topology of the entire SDN infrastructure. However, discovering a network topology is challenging due to: 1) the frequent migration of the virtual machines in the data centers; 2) lack of authentication mechanisms; 3) scarcity of the SDN standards; and 4) integration of security mechanisms for the topology discovery. To this end, in this paper, we present a comprehensive survey of the topology discovery and the associated security implications in SDNs. This survey provides discussions related to the possible threats relevant to each layer of the SDN architecture, highlights the role of the topology discovery in the traditional network and SDN, presents a thematic taxonomy of topology discovery in SDN, and provides insights into the potential threats to the topology discovery along with its state-of-the-art solutions in SDN. Finally, this survey also presents future challenges and research directions in the field of SDN topology discovery.