Self-configuring microgrids : stabilizing microgrids to support the growing demand

Abstract

Tackling the challenge of stable operation, the thesis proposes a novel approach for micro-grid stability by exploiting demand side management. The balance of supply and demand in a mi-crogrid, must be ensured all the times to guarantee the safe operation, is traditionally maintained by controlling generation reserves. However, an isolated microgrid is likely to undergo the situation of power generation shortage because of growing energy demand. This work utilizes the potential of communication technology for direct load control to reduce the demand during imbalance situations. Considering rural areas of developing countries as target application areas, the proposed microgrid system is self-organizing in the sense that it is able to adapt to changing generation and/or load con-figurations without the need of specialists to change parameters of the microgrid central controller.<br />The self-configuration of the proposed system is achieved by disconnecting the unessential loads from the grid after identifying the types of connected loads automatically. The microgrid central controller communicates with the loads and directs them to isolate from the grid to reduce the over-all demand especially during peak load hours; so that the system is able to cope with more demand than it was actually designed for. Each load is equipped with a control node to become an intelligent load. The control node is a simple circuitry, containing a communication node, power measuring device and switch that can isolate the load from the grid. Load disconnection is decided on the basis of control algorithms implemented in the central controller. Different load management algorithms are tested and evaluated by simulation, and results show that the proposed system increases the availability of consistent energy supply. Moreover, besides offering stable microgrid operation with demand growth support in an automated manner, self-configuring attribute makes the microgrid an easy to use (i.e.<br />plug-and-play) system that requires minimum maintenance activities resulting in reduced operational and maintenance costs. Such a self-configuring microgrid is the power system of choice for the electrification of off-grid rural areas because of limited resources and lack of ex-perts' availability at remote locations.