On the three-step control methodology for Smart Grids

Energy usage, dependability of energy supply and climate change are important topics in society. Today, a number of trends can be recognized in the electricity consumption and generation. On the one hand, the electricity consumption increases and becomes more žuctuating. is is caused by increasing economic activity and prosperity, but also by a shiŸ towards more electricity supplied devices, for example electrical cars. On the other hand, the projected reduction in CO2 emission requires the introduction of generation based on renewable sources. ese renewable sources are based on uncontrollable and very žuctuating sun-, waterand wind power. ese trends introduce challenges tomaintain a reliable and ašordable electricity supply. Fluctuations in electricity demand decrease the e›ciency of conventional power plants. Furthermore, peak demands determine the required generation and transportation capacity, higher peaks require more generation and transportation capacity. Moreover, renewable generation oŸen does not match the demand prole and in addition to that ine›cient peak power plants have to supply this žuctuating mismatch between generation and demand. Furthermore, since all produced electricity must be consumed, in the current electricity supply system the lowest demand results in an upper bound on the renewable generation. erefore, only a limited amount of the demand can be supplied by renewable sources. A solution to these problems may be to transform domestic customers from static consumers into active participants in the production process. Consumer participation can be achieved through the development of new (domestic) devices with controllable load, micro-generation and domestic energy storage of both heat and electricity. ese devices have potential to shiŸ electricity consumption in time without harming the comfort of the residents. Examples of devices with optimization potential are (smart) freezers and fridges which can adjust their cooling cycles to shiŸ their electricity load and (electrical car) batteries that can temporarily store excess electricity. To exploit this optimization potential on a large scale, a global control methodology is required. In this thesis the above mentioned challenges and optimization potential are studied and a control methodology is derived. is control methodology aims 1) to achieve a more e›cient use of the generated electricity of existing power plants, 2) to facilitate the large scale introduction of renewable sources and 3) to allow large scale introduction of new technologies for production, consumption and storage while at the same time maintaining grid stability and ensuring a reliable and ašordable supply.