Stage Smart Grid Issues: Power System Modelling H/F Job In EUROPE-France-Île-de-France-Massy

The vision of the smart grid is to break down barriers between transmission and distribution, communications, and back office systems to create a fully integrated network. Today's power grid is primarily composed of central generating stations and electromechanical power delivery systems operated from control centres. However, the system is transforming itself into a smart grid that integrates a multitude of distributed energy resources. Almost all distributed generation is used as back-up power and is unconnected to the grid The grid will achieve greater throughput, thus lowering power costs. Grid upgrades that increase the throughput of the transmission grid and optimize power flows will reduce waste and maximize use of the lowest-cost generation resources. Better harmonization of the distribution and local load servicing functions with interregional energy flows and transmission traffic will also improve utilization of the existing system assets. The emergence of competitive Distributed Energy Resources (DER) solutions, and the political push towards sustainable development will help the penetration of DER on medium (MV) and low (LV) voltage grids.

The continuity and quality of electricity delivered safely and economically by today's and future's electrical power networks are important for both developed and developing economies. In order to ensure safety and/or to identify economic network investments, it is requested to perform accurate modelling of power system equipment as well as correct fault analysis of electrical networks. In addition, environmental and economic factors require engineers to maximize the use of existing assets which in turn require accurate modelling and analysis techniques.

According to the purpose of the system study, it is necessary to select appropriate models in terms of accuracy, complexity and computational burden. Selecting improper models for power system components may lead to erroneous conclusions. Generators are important in system stability studies, and are modelled in dissimilar ways depending on the objective of the study. For instance, in complex analyses, such as small-disturbance stability, it may be required to use either generator subtransient or transient stability models that are represented by means of DAEs (Differential Algebraic Equations). All researchers and utility engineers use this small disturbance model for stability studies. In 2009, our research group has found very interesting results in terms of scale-free exact linear model to describe power systems, as shown in figures 3 and 4. This obtained model is not only representative for small disturbance but in all state space. The improved model can be adopted when an accurate representation of the nonlinear swing equation is necessary. The power system modelling study has also been carried out for model reduction of multi-machines system as well as for inter-areas oscillations phenomena. Thanks to the obtained model, analysis of the frequency and the associated active power of an interconnected machines system become easier. Moreover, electric network transient stability and FACTS placement/coordination are also concerned. The obtained model could change the study of stability for power system and benefit to many dedicated software's.

Load models are categorized as static and dynamic. Dynamic load models are more complicated, and are used mainly for transient stability analysis. On the other hand, static models are better suited for power flow and small-disturbance stability analysis. Our aim is to have accurate load models representing correct behaviour of considered systems. For example, if one wants to study the impact of industrial power plants on power network, one need a reduced and accurate model of the network in association with a simplified industrial power plant models.

The aim of this training is to study the modelling of power system and specially the case of industrial network protection and stability. The trainee will use a dedicated power system simulating tool.