Candidate: Farid Farmani
Title: Frequency control via demand response in smart grid
Date: May 10, 2018
Time: 2:00pm
Place: EIT 3142
Supervisor(s): Zhuang, Weihua
Abstract:
In order to have a reliable microgrid (MG) system, we need to always keep the frequency within an acceptable range. However, due to disturbances happening in a MG system (e.g., sudden load change, etc.), it can experience major or minor deviations in frequency, which need to be controlled within seconds to provide the system stability. In order to maintain the balance between supply and demand, traditionally, generation side controllers have been utilized to stabilize the power system frequency. These systems add high operational cost, which is not suitable for power system operators. With the introduction of smart grid, more and more renewable energy sources are to be used in the power system. The intermittent behavior of these energy resources, as well as high operation cost of conventional controllers, has made researchers seek for new alternatives. In a smart grid environment, demand response (DR) programs can be considered as a promising alternative for the conventional controllers to efficiently contribute to the frequency regulation by switching responsive loads on or off. DR programs can reduce the amount of reserve required, and hence, are more cost efficient. Moreover, they can act very fast and can provide a wide range of operation time from a few seconds to several minutes.
Thermostatically controlled loads (TCLs) are proper candidates to participate in frequency regulation programs. However, individual TCLs do not have a noticeable impact on frequency due to small size and they should be aggregated in order to have a considerable effect on frequency. Nevertheless, there are still many challenges which should be addressed in order to make use of TCLs for frequency control in smart grid. In this regard, proper aggregated load models and control algorithms for TCLs contributing to this service need to be investigated. In this presentation we present an aggregation model for TCLs as well as a control strategy to coordinate power provided from DR participants with that of generation side of the MG to keep system frequency within its desired range.