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Since the 1940s, Minnkota Power Cooperative, Great River Energy (then United Power Association and Cooperative Power), Dairyland Power Cooperative, and East River Electric Power Cooperative in the Midwestern United States have deployed nearly 600,000 load management devices with their more-than 1.2 million member-owners. Building upon technological innovation systems theory and using case studies of the co-ops, I show the importance of intermediaries such as contractors and distribution cooperative managers in facilitating the deployment of these distributed energy resources for the co-ops. I then use common pool resource rules to highlight the intermediary functions that helped drive the common pool resource of the co-ops’ innovations. This research has implications for future decarbonized distributed energy resource deployments and the electrification of formerly fossil-fueled technologies. More widely, this study shows the potential need for appropriate levels, connectedness, and locations of polycentric governance within a far-reaching, deep, and distributed energy resource transition.

Utilities, faced with increasingly limited resources, strive to maintain high levels of reliability in energy delivery by adopting improved methodologies in planning, operation, construction and maintenance. On the other hand, driven by steady research and development and increase in sales volume, the cost of deploying PV systems has been in constant decline since their first introduction to the market. The increased level of penetration of distributed energy resources in power distribution infrastructure presents various benefits such as loss reduction, resilience against cascading failures and access to more diversified resources. However, serious challenges and risks must be addressed to ensure continuity and reliability of service. By integrating necessary communication and control infrastructure into the distribution system, to develop a practically coordinated system of distributed resources, controllable load/generation centers will be developed which provide substantial flexibility for the operation of the distribution system. On the other hand, such a complex distributed system is prone to instability and black outs due to lack of a major "infinite" supply and other unpredicted variations in load and generation, which must be addressed. To devise a comprehensive method for coordination between Distributed Energy Resources in order to achieve a collective goal, is the key point to provide a fully functional and reliable power distribution system incorporating distributed energy resources. A road map to develop such comprehensive coordination system is explained and supporting scenarios and their associated simulation results are then elaborated. The proposed road map describes necessary steps to build a comprehensive solution for coordination between multiple agents in a microgrid or distribution feeder.'

Abstract: Recently, riding through grid faults and supporting the grid voltage under faults have become major requirements in distributed energy resource (DER) units. There have been also extensive efforts in academia and industry to develop and implement control strategies to ride through voltage disturbances, and even to support the grid under such faulted conditions which can be named as low-voltage ride-through (LVRT) technology. Therefore, a comprehensive and comparative study seems to be very useful in order to analyze and discuss available LVRT reference-current-generation (LVRT-RCG) strategies in converter-interfaced DER units, compare their performances, and introduce their pros and cons. This thesis studies all existing (nine) LVRT-RCG strategies available in the literature. These strategies are categorized into two main groups. The analytical evaluations and mathematical assessments of all LVRT-RCG strategies are performed. For a comprehensive evaluation of these strategies, the following important parameters are used in this study: instantaneous active/reactive powers oscillation and maximum phase currents. Analytical expressions of these parameters are formulated, evaluated and used to conduct several evaluation and comparative studies on different strategies. Based on the obtained formulas for the maximum phase currents, the maximum allowable reactive power delivery (MARPD) equations are proposed specifically for each of the nine LVRT-RCG strategies. Proposed equations help each LVRT-RCG technique to provide their best voltage support under the specific maximum phase current restrictions imposed by DER owners. Using different test cases, the strategies are compared and the proposed equations are validated. This thesis can be helpful to evaluate the performance of existing LVRT-RCG strategies, solve their existing drawbacks, exploit the best performance out of each, combine their individual capabilities, and improve them.

The demand for electric power has been steadily increasing, and this trend is expected to continue over the coming decades. With the increased usage of fossil fuels, there has been a growing concern with the environmental impacts of electric power generation. Therefore, penetration of renewable sources of energy in the modern electric grid has also been increasing. The intermittent nature of renewables introduces uncertainty in the electric grid, which has a negative impact on grid reliability. To address these challenges, renewables are supplemented with energy storage systems (ESS). This dissertation evaluates ESS technologies according to their applications. A generalized method is proposed for ESS sizing for microgrids. This method can be successfully applied to any load profile; it also takes into account operating temperature and aging factors.In addition, this dissertation presents a variety of ESS life balancing solutions using the new framework of Flexible Distribution of EneRgy and Storage Resources (FDERS). It is based on an in-situ reconfiguration approach through `virtual’ reactance and/or `virtual’ inertia to change the `electrical’ position of each DER without physically displacing it in the microgrid system. Several approaches toward balancing the ESS utilization are proposed taking advantage of the flexibility offered by FDERS framework. It is shown that the estimated ESS cycle life is dependent on factors such as cycling sequence, pattern, and occurrence.Finally, this dissertation proposes a multi-agent based fleet vehicle-to-grid (V2G) control strategy that intelligently computes each vehicle’s load share based on its battery state-of-health (SoH). Unlike state-of-the-art V2G systems, which treat all the fleet electric vehicles equally with no regard to their diverse driving histories and unequal battery aging, the proposed control strategy employs a programmable on-board smart device to estimate the vehicle’s battery SoH. When multiple vehicles are connected to an isolated microgrid, the individual load shares are dependent on their latest SoH value.