26 research outputs found
An algebraic approach for determination of DG parameters to support voltage profiles in radial distribution networks
No full textRapidly increasing electricity demands and capacity shortage of transmission and distribution facilities are the main driving forces for the growth of Distributed Generation (DG) integration in power grids. One of the reasons for choosing a DG is its ability to support voltage in a distribution system. Selection of effective DG characteristics and DG parameters is a significant concern of distribution system planners to obtain maximum potential benefits from the DG unit. This paper addresses the issue of improving the network voltage profile in distribution systems by installing a DG of the most suitable size, at a suitable location. An analytical approach is developed based on algebraic equations for uniformly distributed loads to determine the optimal operation, size and location of the DG in order to achieve required levels of network voltage. The developed method is simple to use for conceptual design and analysis of distribution system expansion with a DG and suitable for a quick estimation of DG parameters (such as optimal operating angle, size and location of a DG system) in a radial network. A practical network is used to verify the proposed technique and test results are presented
Response coordination of distributed generation and tap changers for voltage support
No full textThe recent introduction of the competitive electricity market in many countries has sparked a renew trend in connecting small-size generators into distribution networks. Those new generators together with different other types of equipment such as On-load Tap Changing (OLTC) transformer, shunt capacitors, shunt reactors, etc, will all participate into the voltage regulation process in the power systems. Poor coordination between these devices may cause unnecessary operations, and consequently unnecessary wear, unnecessary energy consumption as well as poor voltage quality. In this paper, we present an innovative strategy to coordinate the voltage control actions in a distribution system with more than one voltage regulating device. The method for voltage control coordination is developed based on the priority level of each regulating device and implemented through communication. A sensitivity-based technique for determining the control zones of the regulating devices has been developed. A practical system with tap changers and distributed generator has been chosen to test the developed control method. Simulations have been carried out extensively on a practical distribution system to show the effectiveness of the method
A decentralized multi-agent approach to prevent voltage collapse in a large power system
No full textInvestigating the Operation of Multiple Voltage Regulators and DG in a Distribution Feeder
No full textAbstractIntegration of distributed generation (DG) in a distribution network may introduce adverse effects including control interaction, oscillatory transients and operational conflicts. This paper investigates the operation of multiple voltage regulators such as on-load tap changer (OLTC) and step voltage regulator (SVR), and DG in a medium voltage distribution feeder. Investigations have been carried out using time domain simulation studies conducted using MATLAB-SimPowerSystems. The results are reported for a case study involving radial distribution feeder, derived from New South Wales (NSW) electricity distribution network in Australia
Optimal allocation of renewable energy resources for minimising emissions in distribution networks
No full textControl stabilisation of multiple distributed generation
No full textGrid connected distributed generation (DG) increases reliability and additional benefits for consumers as well as utilities. Recently, different types of DG are connected into distribution networks. Different control phenomena are applied based on types of DG. The stable and reliable operation of such power system requires sophisticated control. This paper presents a small-signal analysis for investigating dynamic behaviours of the system with multiple DG and also investigating control interactions between different types of DG. Dynamic model of a synchronous generator (SG) based hydro generator and inverter based photovoltaic/ wind distributed resources are considered for case studies to investigate grid connected and islanding mode of operation
Damping of low-frequency oscillations and improving power system stability via auto-tuned PI stabilizer using Takagi-Sugeno fuzzy logic
No full textThis paper proposes a Takagi-Sugeno (TS) fuzzy gain-scheduling PI stabilizer to damp the power system low-frequency oscillations and enhance power system stability. The work describes the construction of appropriate fuzzy membership functions and rules for a Power System Stabilizer (PSS) so that its proportional and integral gains can be automatically tuned in real-time to react to changes in the system operating conditions. To find the optimal number and locations of required stabilizers, this paper uses the participation factor method. Simulation results on a practical power system demonstrate that the proposed stabilizer is effective in damping low-frequency oscillations as well as improving system dynamic stability and voltage profile. In addition, the proposed approach provides superior performance when compared to a conventional PI PSS. © 2011 Elsevier Ltd. All rights reserved
Estimation of capacity credits for wind generation plants in the south east australian power grid
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