The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This paper proposes a voltage regulation method using distributed energy storage systems (ESSs) in low-voltage (LV) distribution networks with high penetration of rooftop photovoltaics. The impact of renewable based distributed generation units on feeder voltages is investigated in detail. The voltage regulation method consists of two stages. The distributed control is proposed in stage one to coordinate...
The main objective of this paper is to study the influence of dispersed generation upon the steady state of distribution networks, especially upon the voltage level, active power losses and branch currents flow. Power flow calculation of electrical distribution networks with and without distributed generation was realized in MATLAB environment, based on backward-forward sweep. The tests were performed...
This paper describes the modeling of automatically operated local controllers, based on the scheduled, measured or calculated values of the locally affected network equipment in real time operation of Distribution Management System - Control Center. The model presented is operated in unbalanced, unsymmetrical distribution networks and analyzed in phase domain. Simulated Locally controlled equipment...
Radial distribution systems (RDS) have lines with high R/X ratios and hence Newton based methods were not reliable to solve their set of bus power balance equations. Historically, a recursive solution method using a set of voltage equations and its variants are very popular to determine a voltage solution of a RDS. Consequently, use of classical optimization was not possible. Recent developments in...
The electricity production field is undergoing a significant change because of both the liberalization of the sector and the policies to support renewable energy sources (RES) and those assimilated to them; in particular, among the latter, the cogeneration technology for civil applications, able to improve the overall energy efficiency, is taken into account in this paper. The electrical generation...
The paper presents the results of few numerical applications for sustaining the idea of unbalancing transversal capacitive compensation like a method for balancing the load of the electrical distribution networks and consequently to increase the voltage quality and the efficiency. The load balancing, analytical described by the annulment of negative component of the currents on the load phases, is...
With the increase of distributed generation (DG) connections, circuit overload and voltage violation will occur for some distribution networks. However, building new lines to accommodate DG may pay high monetary and environment costs. A new procedure of distribution network reinforcement taking the active management means into consideration is proposed in this paper. Models and solution methods for...
While it is difficult to estimate how much distributed generation (DG) capacity will be connected to distribution systems in the coming years, it is certain that increasing penetration levels require robust tools that help assess the capabilities and requirements of the networks in order to produce the best planning strategies. This work presents an overview of some of the uses to which a tailored...
This paper discusses the authors' experience of developing an active network management system for use by two different distribution network operators (DNOs) in the UK with differing network management requirements. The paper describes the fundamental building blocks of AuRA-NMS (autonomous regional active network management system) and how their development was driven by the requirements of the partner...
The problem of choosing the optimal location and size for shunt capacitors in unbalanced distribution systems can be formulated as a mixed, non-linear, constrained multi-objective optimization problem, and is usually solved in deterministic scenarios. However, distribution systems are stochastic in nature, which leads to inaccurate deterministic solutions. To take into account the unavoidable uncertainties...
??Smart Grid?? can be defined as getting the power to the customer the smartest way possible with the least amount of losses. One of the ways to control the power flow over the transmission line is to insert a phase angle regulating transformer (PAR) in the line. PAR's have long been dreaded by the protection engineer as a very complex device with many different currents that make it tedious at best...
Traditional power flow algorithms are not applicable to distribution network with distributed generation because the addition of distributed generation onto distribution networks may result in bi-directional power flow. The models of different type distributed generations in power flow calculation were presented as well as an improved back/forward sweep algorithm. Reactive power apportion method was...
The conventional load flow methods for transmission systems could not be utilised for distribution systems, due to their especial characteristics. If methods like Newton-Raphson and Fast-Decoupled are used for distribution systems, the probability of their convergence will be low. Therefore, due to inherent characteristics of distribution systems, it is essential to develop the distribution version...
Distribution networks are increasingly required to host medium to large volumes of distributed (renewable) generation capacity. To facilitate high penetration levels of these new network participants it is crucial to adopt new control strategies in which the distribution systems are operated actively. The wide deployment of schemes such as coordinated voltage control (CVC) or non-firm connections...
Modern shipboard power systems of surface vessels require accurate and efficient load flow solutions to keep its grid voltage static stable. A novel approach to Particle Swarm Optimization (PSO) algorithm for solving load flow calculation problem of integrated shipboard power systems is presented in this paper. The proposed new technique evolves a unique version of PSO by converting forward-backward...
This paper presents a unique method to determine the weakest branch or the overstressed branch in a distribution network. This radial feature of the network has been fully exploited to establish the concept of local voltage stability indicator in terms of reactive power. The effectiveness of the proposed method has been successfully tested in 12 bus radial distribution system and the results are found...
This paper discusses AuRA-NMS, an autonomous regional active network management system currently being developed in the UK through a partnership between several UK universities, two distribution network operators (DNO) and ABB. The scope of control to be undertaken by AuRA-NMS includes: automatic restoration, voltage control, power flow management and implementation of network performance optimisation...
The way in which electricity networks operate is going through a period of significant change, with global issues causing an overhaul of the industry in countries across the world. Renewable generation technologies have a growing presence and increasing penetrations of generation are being connected at distribution level. Levels of network automation are on the rise, so too is the consumer demand...
One of the major problems in development of distributed generation (DG) is voltage control derived from reverse power. In order that voltage variation may not degrade customer voltage supply quality, feeder voltage should be maintained within the permissible range against DG connection. To improve the voltage profile in distribution network with DG, this paper proposes several voltage control strategies...
A two-step algorithm for the optimal placement of voltage regulators in distribution systems is presented in this paper. In the first step, voltage regulators are placed (and the tap position is determined) at candidate buses, aiming at minimizing voltage drops and real power losses. In the second step, an attempt to reduce the number of voltage regulators is made, taking into consideration economical...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.