Realizable constraint driven capacitor placement and control sequences for voltage spread reduction in distribution systems.

摘要

There is a continued focus on advancing and diversifying the US electric energy sector. Some federal and state initiatives have been imposed to: reduce system peak load, increase the amount of renewable generators, and increase the number of demand response participants. In distribution systems, various combinations of network devices (e.g. capacitors, distributed generators, loads) are used to achieve a reduction in peak load. Historically, capacitors have been installed and employed by system operators for reactive power compensation, voltage regulation, power factor correction and energy loss reduction.;In this thesis, capacitor placement and control sequences for voltage spread reduction in distribution systems is developed and delivered. Additionally, direct load control participants and photovoltaic generators are included in the control problem in order to investigate impacts of federal and state peak load reduction goals.;Existing capacitor placement and control problem formulations do not address bulk transmission system requirements and whether an optimal solution is physically attainable by system operators. Here, two new constraints are included in the problem formulation. A substation reactive power constraint is included in order to comply with the transmission system operating requirements. A voltage rise constraint is included so that bus voltage magnitudes between pre and post device switch actions are held to an acceptable change (rise/drop) in bus voltage. Subsequently, heuristic based greedy algorithms were developed to find a solution.;The results show that constraint-driven methodologies are needed to generate control sequences, which can realize the objectives. The order in which capacitors actions are taken throughout a day is significant and should be guided by the voltage rise constraint. A set of feasible non-inferior solutions which are attained via a search of feasible switching sequences was found. Also, the transmission system reactive power requirements significantly impact the placement and control results. DLC and PhV results showed that a tradeoff exists between a reduction in real power and increase in the total reactive power in the circuit.