Radial distribution network reconfiguration for power losses reduction using a modified particle swarm optimisation

Abstract: Recently, losses reduction gained a great deal of attention in distribution system due to low-voltage level and the high-current passing through the lines, pushing the distribution utilities to improve their profit margins on one hand by reducing the unnecessary operational cost, and improving their delivered power quality on the other hand by maintaining the system reliability, and the continuity of supply for varying load demand. Load balancing, voltage regulation, network reconfiguration and others are different techniques used to reduce the losses. This study addresses the distribution network reconfiguration to minimise the network losses. A new modified form of particle swarm optimisation (PSO) is used to identify the optimal configuration of distribution network effectively. The difference between the modified PSO (MPSO) algorithms and the typical one is the filtered random selective search space for initial position, which is proposed to accelerate the algorithm for reaching the optimum solution. The suggested MPSO is tested via 33 and 69 IEEE networks. A benchmark comparison has been conducted to prove the effectiveness of MPSO compared with previous optimisation techniques

Utilization of Battery Energy Storage Systems (BESS) in Smart Grid: A Review

The uncertainty in fuel cost, the ageing of most existing grid, the lack of utilities’ supply capacity to respond to the increasing load demand, and the lack of automatically power restoration, accelerate the need to modernize the distribution network by introducing new technologies, putting the smart grid (SG) on spot. The aim of this paper is to carry out a detailed survey of the major requirements of (SG) and discuss the operational challenges arising from the integration of distributed generation (DG) in distribution networks (DN). These requirements dictate the necessity to review the energy and communication infrastructure, the automatic control, metering and monitoring systems, and highlight the features of smart protection system for a robust and efficient distribution grid. In addition, the paper aims to classify the energy storage systems (ESS) and explain their role for utilities, consumers and for environment. This includes the pumped hydro systems (PHS) and compressed air systems (CAS), battery energy storage systems (BESSs), double layer and superconductive capacitors, and electric vehicles (EVs). Since BESSs emerged as one of the most promising technology for several power applications, the paper presents an overview of their main features, management and control systems and operational modes. A survey about the utilization of BESSs in power system is presented

Modelling of induction motors for system faults and transient stability studies

The research carried out in this thesis was mainly concerned with the effects of large induction motors and their transient performance in power systems. Computer packages using the three phase co-ordinate frame of reference were developed to simulate the induction motor transient performance. A technique using matrix algebra was developed to allow extension of the three phase co-ordinate method to analyse asymmetrical and symmetrical faults on both sides of the three phase delta-star transformer which is usually required when connecting large induction motors to the supply system. System simulation, applying these two techniques, was used to study the transient stability of a power system. The response of a typical system, loaded with a group of large induction motors, two three-phase delta-star transformers, a synchronous generator and an infinite system was analysed. The computer software developed to study this system has the advantage that different types of fault at different locations can be studied by simple changes in input data. The research also involved investigating the possibility of using different integrating routines such as Runge-Kutta-Gill, RungeKutta-Fehlberg and the Predictor-Corrector methods. The investigation enables the reduction of computation time, which is necessary when solving the induction motor equations expressed in terms of the three phase variables. The outcome of this investigation was utilised in analysing an introductory model (containing only minimal control action) of an isolated system having a significant induction motor load compared to the size of the generator energising the system