Reactive power plays an essential role in voltage control and stability in electric power systems. Various Volt/VAR techniques are utilized in electric power systems to maintain the voltage profile within defined acceptable limits and accordingly provide reliability and stability. Reactive power has been commonly generated through large-scale synchronous generators or distributed capacitor banks to provide proper transmission and distribution level system management, however, reactive power can be further used as an effective means to reduce total system operation cost. In this dissertation, an optimal reactive power model is proposed to determine the optimal nodal reactive powers that result in the lowest total system operation cost. Microgrid is introduced as a source of real and reactive power where its capability curve as a single generator unit is further determined and utilized. An optimization-based method is proposed to determine this capability curve. The results of numerical analyses of this proposal show how the reactive power behaves under gradual changing of real power generation in a microgrid and how these two outputs are correlated. This model is further integrated into an optimal power flow problem to show the potential economic benefits of microgrid-generated reactive power of the larger system. The numerical analyses on standard test systems show the performance of the proposed model and provide insights on the role of microgrid as a source of reactive power in the system.
","abstract_html":"<p>Reactive power plays an essential role in voltage control and stability in electric power systems. Various Volt/VAR techniques are utilized in electric power systems to maintain the voltage profile within defined acceptable limits and accordingly provide reliability and stability. Reactive power has been commonly generated through large-scale synchronous generators or distributed capacitor banks to provide proper transmission and distribution level system management, however, reactive power can be further used as an effective means to reduce total system operation cost. In this dissertation, an optimal reactive power model is proposed to determine the optimal nodal reactive powers that result in the lowest total system operation cost. Microgrid is introduced as a source of real and reactive power where its capability curve as a single generator unit is further determined and utilized. An optimization-based method is proposed to determine this capability curve. The results of numerical analyses of this proposal show how the reactive power behaves under gradual changing of real power generation in a microgrid and how these two outputs are correlated. This model is further integrated into an optimal power flow problem to show the potential economic benefits of microgrid-generated reactive power of the larger system. The numerical analyses on standard test systems show the performance of the proposed model and provide insights on the role of microgrid as a source of reactive power in the system.</p>","abstract_has_math":false,"creators":["Hasan, Sarhan"],"institution":null,"degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":null,"degree_department":null,"school":null,"contributors":["Amin Khodaei","Kimon P. Valvanis","Mohammad Abdul Matin","Shimelis Assefa"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2020,"date_issued":"2020-01-01T08:00:00Z","date_published":"2020-01-01T08:00:00Z","updated_at":"2026-07-24T02:03:35Z","subjects":["Critical bus","Microgrid","Objective function","Operation cost","Reactive power","Solar","Computer Engineering","Electrical and Computer Engineering","Power and Energy"],"languages":["en"],"rights":["Copyright is held by the author. User is responsible for all copyright compliance.
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"]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Microgrid-Enabled Reactive Power Support to Enhance Grid Economics"]}]}],"canonical_facts":{"dc:contributor":["Amin Khodaei","Kimon P. Valvanis","Mohammad Abdul Matin","Shimelis Assefa"],"dc:creator":["Hasan, Sarhan"],"dc:date.available":["2021-02-19T08:00:00Z"],"dc:description.abstract":["Reactive power plays an essential role in voltage control and stability in electric power systems. Various Volt/VAR techniques are utilized in electric power systems to maintain the voltage profile within defined acceptable limits and accordingly provide reliability and stability. Reactive power has been commonly generated through large-scale synchronous generators or distributed capacitor banks to provide proper transmission and distribution level system management, however, reactive power can be further used as an effective means to reduce total system operation cost. In this dissertation, an optimal reactive power model is proposed to determine the optimal nodal reactive powers that result in the lowest total system operation cost. Microgrid is introduced as a source of real and reactive power where its capability curve as a single generator unit is further determined and utilized. An optimization-based method is proposed to determine this capability curve. The results of numerical analyses of this proposal show how the reactive power behaves under gradual changing of real power generation in a microgrid and how these two outputs are correlated. This model is further integrated into an optimal power flow problem to show the potential economic benefits of microgrid-generated reactive power of the larger system. The numerical analyses on standard test systems show the performance of the proposed model and provide insights on the role of microgrid as a source of reactive power in the system.
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"],"dc:subject":["Critical bus","Microgrid","Objective function","Operation cost","Reactive power","Solar","Computer Engineering","Electrical and Computer Engineering","Power and Energy"],"dc:title":["Microgrid-Enabled Reactive Power Support to Enhance Grid Economics"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."]},"updated_at":"2026-07-24T02:03:35Z"}