Voltage profile of distribution networks with distributed generation are affected significantly due to the integration of distributed generation (DG) on it. This paper presents a way to control voltage of distribution networks with DG using reactive power compensation approach. In this paper, the voltage control approach is shown based on the worst case scenario of the network. To keep the voltage profile within the specified limits, it is essential to regulate the reactive power of the compensators. Finally, based on this concept, a static analysis is done on a 15-bus Japanese distribution system, called Kumumoto system where the system is modified with the inclusion of distributed wind generators, photovoltaics, and synchronous generators.

The classical definitions of various centrality measures are modified to incorporate electrical parameters of the power grid. In this paper three distinct measures of centrality are presented and they are described with suitable examples. The usefulness of these measures are described. Various standard test systems are simulated to find critical nodes of the system. Complex network is a new area of research in power system. Simulation of several systems suggests that the definitions proposed in this paper can be used as a standard.

This paper presents an approach to design a non-singular fast terminal sliding model controller for residual current compensation inverters in compensated distribution networks to compensate the fault current due to most commonly occurred single line-to-ground faults. The main control objective is to completely eliminate the fault current in order to mitigate the impacts of powerline bushfires. A non-singular fast terminal sliding surface is used to design the controller so that the residual current compensation inverter can quickly ensure the desired control performance without experiencing singularity problems. In this scheme, the chattering effects are minimised by replacing the discontinuous function appearing in the control law with a continuous function and the Lyapunov stability theory is utilised to demonstrate the theoretical stability of the control law. This paper also includes an overview of the non-singular terminal sliding model controller as the performance of the non-singular fast terminal sliding model controller is compared with this controller through rigorous simulation results over a range of fault currents. Simulation results clearly demonstrate the faster convergence speed of the non-singular fast terminal sliding model controller over the non-singular terminal sliding model controller for compensating the fault current and hence, mitigating powerline bushfires.

Abstract-In this paper, a new methodology for stability assessment of a smart power system is proposed. The key to this assessment is an index called betweenness index which is based on ideas from complex network theory. The proposed betweenness index is an improvement of previous works since it considers the actual real power flow through the transmission lines along the network. Furthermore, this work initiates a new area for complex system research to assess the stability of the power system. Index Terms--Transient stability, complex network, smart grid, bus admittance matrix. I. INTRODUCTIONANY of the public infrastructures like electric power network are subject to two types of threats: intentional and accidental [1]. Intentional attack can be subdivided into physical or cyber attacks. According to US government accountability office, in 2002, 70 percent of power companies experienced some kind of severe cyber attack to their computing or energy management systems [2]. Physical attacks against key elements of the system are also common. Whether it is going to be a physical or cyber attack, the modern smart grid must resist. The designers of the modern grid should plan for a dedicated, well planned attack prevention strategy. For the modern grid to resist attack it must reduce the vulnerability of the grid to attack by protecting key assets from cyber, physical, or accidental attacks. The complex networks approach to electric power network security would identify key vulnerabilities, assess the likelihood of threats, and determine the consequences of attacks. One of the particular goals of the security program is to identify critical sites and systems.Complex networks, which had been the main research area of graph theory, have drawn interest of researchers from various disciplines as graph theory began to focus on statistics and analytics [3]. A complex network was proposed as a random network [4]. There are other networks whose behaviour falls in between regular and random, and these are classified as small-world networks [5]- [7]. A power system usually falls in the small-world network category [8].A. B. M. Nasiruzzaman and H. R. Pota are with School of Engineering and Information Technology (SEIT) of University of New South Wales at the Australian Defence Force Academy (UNSW@ADFA), Northcott Drive, Canberra, ACT 2600, Australia (e-mail: nasiruzzaman@ieee.org, and h.pota@adfa.edu.au).Complex network theory has been used to model the power system and analyze its several aspects [8]- [13]. The structural vulnerability of the North American power grid was studied after the August 2003 blackout affecting the United States [14]. Similarly, the large scale blackouts and cascading failures motivated analysis of the Italian power grid based on the model for cascading failures [13], [15]. How redistribution of load on nodes due to failure of certain important nodes can cause a cascading failure was also demonstrated [16], [17].Vulnerability analysis models [6]- [11] were initially proposed for complex abstract net...