Now showing 1 - 7 of 7
  • Publication
    Impact of high penetrations of micro-generation on low voltage distribution networks
    Due to rising fossil fuel and electricity prices and the overall need to reduce carbon emissions, there is a growing interest in the utilisation of micro-generation amongst electricity consumers and governments alike. Electricity consumers are installing small scale generators on their premises, which are also being connected to existing low voltage (LV) electricity supply networks. High penetrations of micro-generation may present challenges to the planning and operation of LV electricity networks. This is due to LV distribution networks being designed for delivery of electricity from sub-stations to the consumers and not for accommodating generation. The aim of the work presented in this paper is to examine the effect of high penetrations of micro-generation on the voltage levels of a section of existing Irish LV distribution network.
      4506
  • Publication
    Stochastic analysis of the impact of electric vehicles on distribution networks
    Advances in the development of electric vehicles, along with policy incentives, will see a wider uptake of this technology in the transport sector in future years. However, large penetrations of EVs could lead to adverse effects on power system networks, especially at the residential distribution network level. These effects could include excessive voltage drop and thermal loading of network components. A stochastic method is developed to take account of the uncertainties associated with EV charging and the technique is implemented on a residential test network using power system simulation software. The results show how voltage levels, component loading network losses are impacted from EV charging, taking into account the probabilistic behaviour of the EV owners.
      805
  • Publication
    Impact assessment of varying penetrations of electric vehicles on low voltage distribution systems
    Advances in the development of electric vehicles, along with policy incentives will see a wider uptake of this technology in the transport sector in future years. However, the widespread implementation of electric vehicles could lead to adverse effects on power system networks, especially existing distribution networks. This work investigates some of the potential impacts from various levels of uncontrolled electric vehicle charging on a test distribution network. The network is examined under worst case scenario conditions for residential electricity demand in an effort to assess the full impact from electric vehicles. The results demonstrate that even for relatively modest levels of electric vehicle charging, both the voltage and thermal loading levels can exceed safe operating limits. The results also indicate the importance of assessing each phase on the network separately in order to capture the full effects of uncontrolled electric vehicle charging on the network.
      2707Scopus© Citations 158
  • Publication
    Controlled charging of electric vehicles in residential distribution networks
    (Institute of Electrical and Electronics Engineers, 2012-10) ; ; ;
    The integration of electric vehicles (EVs) poses potential issues for low voltage (LV) distribution networks, such as voltage deviations and overloading of equipment. Controlled EV charging is seen as one possibility for reducing, or even eliminating, these issues. This work presents an optimisation method which focuses on controlling the rate at which EVs charge over a 24-hour time horizon, subject to certain constraints. A sample distribution network is used and the optimisation tool is tested for multiple objective functions.
      1022Scopus© Citations 10
  • Publication
    Local Versus Centralized Charging Strategies for Electric Vehicles in Low Voltage Distribution Systems
    (Institute of Electrical and Electronics Engineers, 2012-06) ; ;
    Controlled charging of electric vehicles offers a potential solution to accommodating large numbers of such vehicles on existing distribution networks without the need for widespread upgrading of network infrastructure. Here, a local control technique is proposed whereby individual electric vehicle charging units attempt to maximise their own charging rate for their vehicle while maintaining local network conditions within acceptable limits. Simulations are performed to demonstrate the benefits of the technique on a test distribution network. The results of the method are also compared to those from a centralized control method whereby EV charging is controlled by a central controller. The paper outlines the advantages and disadvantages of both strategies in terms of capacity utilization and total energy delivered to charging EVs.
      6477Scopus© Citations 199
  • Publication
    Optimal charging of electric vehicles in low-voltage distribution systems
    Advances in the development of electric vehicles, along with policy incentives will see a wider uptake of this technology in the transport sector in future years. However, the widespread adoption of electric vehicles could lead to adverse effects on the power system, especially for existing distribution networks. These effects would include excessive voltage drops and overloading of network components, which occur mainly during periods of simultaneous charging of large numbers of electric vehicles. This paper demonstrates how controlling the rate at which electric vehicles charge can lead to better utilisation of existing networks. A technique based on linear programming is employed, which determines the optimal charging rate for each electric vehicle in order to maximise the total power that can be delivered to the vehicles while operating within network limits. The technique is tested on a section of residential distribution network. Results show that, by controlling the charging rate of individual vehicles, high penetrations can be accommodated on existing residential networks with little or no need for upgrading network infrastructure.
      3846Scopus© Citations 450