Engineering Commons^™

Microgrid Energy Management During High-Stress Operation, Thomas Price, Gordon Parker, Gail Vaucher, Robert Jane, Morris Berman

Michigan Tech Publications

We consider the energy management of an isolated microgrid powered by photovoltaics (PV) and fuel-based generation with limited energy storage. The grid may need to shed load or energy when operating in stressed conditions, such as when nighttime electrical loads occur or if there is little energy storage capacity. An energy management system (EMS) can prevent load and energy shedding during stress conditions while minimizing fuel consumption. This is important when the loads are high priority and fuel is in short supply, such as in disaster relief and military applications. One example is a low-power, provisional microgrid deployed temporarily to …

Storage Minimization Of Marine Energy Grids Using Polyphase Power, Salman Husain, Gordon Parker, Wayne W. Weaver

Michigan Tech Publications

Multiple wave energy converter (WEC) buoys can be used to establish a WEC array-powered microgrid collectively forming a Marine Energy Grid (MEG). An oceanic domain with gravity waves will have significant spatial variability in phase, causing the power produced by a WEC array to have high peak-to-average ratios. Minimizing these power fluctuations reduces the demand for large energy storage by WEC array-powered DC microgrids while also reducing losses in the undersea cable to the shore. Designs that reduce energy storage requirements are desirable to reduce deployment and maintenance costs. This work demonstrates that polyphase power in conjunction with an energy …

Real Time Adaptive Relay Settings For Microgrid Protection Verified Using Hardware In Loop, Aadam Harnekar

Dissertations, Master's Theses and Master's Reports

Microgrids with penetration of renewables is imposing new challenges for system protection. Renewables are characterized with high source impedance which limit the short circuit current. The value of short-circuit current is limited due to converters used which limit the current to a maximum of 1.1 to 1.5 times maximum rated load current. This can result in faults during the islanded mode of microgrid to go unnoticed if the relay settings are not adapted to account for it. The presence of such uncleared faults in the microgrid can result in exposing it to overcurrent for a long time which can damage …

A Low-Cost Secure Iot Mechanism For Monitoring And Controlling Polygeneration Microgrids, Josué Martínez-Martínez, Diego Aponte-Roa, Idalides Vergara-Laurens, Wayne Weaver

Michigan Tech Publications

The use of Internet-connected devices at homes has increased to monitor energy consumption. Furthermore, renewable energy sources have also increased, reducing electricity bills. However, the high cost of the equipment limits the use of these technologies. This paper presents a low-cost secured-distributed Internet of Things (IoT) system to monitor and control devices connected in a polygeneration microgrid, as a combined power system for local loads with renewable sources. The proposed mechanism includes a Wireless Sensor Actuator Networked Control System that links network nodes using the IEEE 802.15.4 standard. The Internet communication enables the monitor and control of devices using a …

Characterizing Meteorological Forecast Impact On Microgrid Optimization Performance And Design, Robert Jane, Gordon G. Parker, Gail Vaucher, Morris Berman

Michigan Tech Publications

A microgrid consists of electrical generation sources, energy storage assets, loads, and the ability to function independently, or connect and share power with other electrical grids. Thefocus of this work is on the behavior of a microgrid, with both diesel generator and photovoltaic resources, whose heating or cooling loads are influenced by local meteorological conditions. Themicrogrid's fuel consumption and energy storage requirement were then examined as a function of the atmospheric conditions used by its energy management strategy (EMS). A fuel-optimal EMS, able to exploit meteorological forecasts, was developed and evaluated using a hybrid microgrid simulation. Weather forecast update periods …

Optimal Mission Planning Of Autonomous Mobile Agents For Applications In Microgrids, Sensor Networks, And Military Reconnaissance, Casey D. Majhor

Dissertations, Master's Theses and Master's Reports

As technology advances, the use of collaborative autonomous mobile systems for various applications will become evermore prevalent. One interesting application of these multi-agent systems is for autonomous mobile microgrids. These systems will play an increasingly important role in applications such as military special operations for mobile ad-hoc power infrastructures and for intelligence, surveillance, and reconnaissance missions. In performing these operations with these autonomous energy assets, there is a crucial need to optimize their functionality according to their specific application and mission. Challenges arise in determining mission characteristics such as how each resource should operate, when, where, and for how long. …

Optimal And Decentralized Control Strategies For Inverter-Based Ac Microgrids, Michael D. Cook, Eddy H. Trinklein, Gordon Parker, Rush D. Robinett Iii, Wayne Weaver

Michigan Tech Publications

This paper presents two control strategies: (i) An optimal exergy destruction (OXD) controller and (ii) a decentralized power apportionment (DPA) controller. The OXD controller is an analytical, closed-loop optimal feedforward controller developed utilizing exergy analysis to minimize exergy destruction in an AC inverter microgrid. The OXD controller requires a star or fully connected topology, whereas the DPA operates with no communication among the inverters. The DPA presents a viable alternative to conventional P−ω/Q−V droop control, and does not suffer from fluctuations in bus frequency or steady-state voltage while taking advantage of distributed storage assets necessary for the high penetration of …

Multidimensional Optimal Droop Control For Dc Microgrids In Military Applications, Kaitlyn J. Bunker, Michael D. Cook, Wayne Weaver, Gordon Parker

Michigan Tech Publications

Reliability is a key consideration when microgrid technology is implemented in military applications. Droop control provides a simple option without requiring communication between microgrid components, increasing the control system reliability. However, traditional droop control does not allow the microgrid to utilize much of the power available from a solar resource. This paper applies an optimal multidimensional droop control strategy for a solar resource connected in a microgrid at a military patrol base. Simulation and hardware-in-the-loop experiments of a sample microgrid show that much more power from the solar resource can be utilized, while maintaining the system’s bus voltage around a …

Optimal Multidimensional Droop Control For Wind Resources In Dc Microgrids, Kaitlyn J. Bunker, Wayne Weaver

Michigan Tech Publications

The inclusion of electricity generation from wind in microgrids presents an important opportunity in modern electric power systems. Various control strategies can be pursued for wind resources connected in microgrids, and droop control is a promising option since communication between microgrid components is not required. Traditional droop control does have the drawback of not allowing much or all of the available wind power to be utilized in the microgrid. This paper presents a novel droop control strategy, modifying the traditional approach and building an optimal droop surface at a higher dimension. A method for determining the optimal droop control surface …

Multi-Time Scale Control Of Demand Flexibility In Smart Distribution Networks, Bishnu P. Bhattarai, Kurt S. Myers, Birgitte Bak-Jensen, Sumit Paudyal

Michigan Tech Publications

This paper presents a multi-timescale control strategy to deploy electric vehicle (EV) demand flexibility for simultaneously providing power balancing, grid congestion management, and economic benefits to participating actors. First, an EV charging problem is investigated from consumer, aggregator, and distribution system operator’s perspectives. A hierarchical control architecture (HCA) comprising scheduling, coordinative, and adaptive layers is then designed to realize their coordinative goal. This is realized by integrating multi-time scale controls that work from a day-ahead scheduling up to real-time adaptive control. The performance of the developed method is investigated with high EV penetration in a typical residential distribution grid. The …

Simulation Of Scalability For Autonomous Mobile Microgrids, Nathan Beyers

Dissertations, Master's Theses and Master's Reports

Microgrids are small-scale, decentralized systems for generation, storage, and management of electricity to provide power within a local area. By establishing these microgrids using autonomous robots, they can be made safer and more easily reconfigurable. This thesis presents a plan and outlines the infrastructure needed for scaling up previous experimental work on such systems. This work brings together a variety of tools in the form of both software and hardware to set the stage for how further development can be completed. An architecture for physical testing has been built to validate the full potential of navigation and making electrical connections …

State Of Charge Balancing Droop Control, Rui Hu

Dissertations, Master's Theses and Master's Reports - Open

This thesis presents a load sharing method applied in a distributed micro grid system. The goal of this method is to balance the state-of-charge (SoC) of each parallel connected battery and make it possible to detect the average SoC of the system by measuring bus voltage for all connected modules. In this method the reference voltage for each battery converter is adjusted by adding a proportional SoC factor. Under such setting the battery with a higher SoC will output more power, whereas the one with lower SoC gives out less. Therefore the higher SoC battery will use its energy faster …

Multidimensional Optimal Droop Control For Wind Resources In Dc Microgrids, Kaitlyn J. Bunker

Dissertations, Master's Theses and Master's Reports - Open

Two important and upcoming technologies, microgrids and electricity generation from wind resources, are increasingly being combined. Various control strategies can be implemented, and droop control provides a simple option without requiring communication between microgrid components. Eliminating the single source of potential failure around the communication system is especially important in remote, islanded microgrids, which are considered in this work. However, traditional droop control does not allow the microgrid to utilize much of the power available from the wind. This dissertation presents a novel droop control strategy, which implements a droop surface in higher dimension than the traditional strategy. The droop …

Autonomous Power Distribution Systems, Barzin Moridian

Dissertations, Master's Theses and Master's Reports - Open

Using robotic systems for many missions that require power distribution can decrease the need for human intervention in such missions significantly. For accomplishing this capability a robotic system capable of autonomous navigation, power systems adaptation, and establishing physical connection needs to be developed. This thesis presents developed path planning and navigation algorithms for an autonomous ground power distribution system. In this work, a survey on existing path planning methods along with two developed algorithms by author is presented. One of these algorithms is a simple path planner suitable for implementation on lab-size platforms. A navigation hierarchy is developed for experimental …

Dc Microgrid Stabilization Through Fuzzy Control Of Interleaved, Heterogeneous Storage Elements, Robert David Smith

Dissertations, Master's Theses and Master's Reports - Open

As microgrid power systems gain prevalence and renewable energy comprises greater and greater portions of distributed generation, energy storage becomes important to offset the higher variance of renewable energy sources and maximize their usefulness. One of the emerging techniques is to utilize a combination of lead-acid batteries and ultracapacitors to provide both short and long-term stabilization to microgrid systems.

The different energy and power characteristics of batteries and ultracapacitors imply that they ought to be utilized in different ways. Traditional linear controls can use these energy storage systems to stabilize a power grid, but cannot effect more complex interactions. This …

Realization Of A Dc Microgrid Using A Hamiltonian Based Controls Solution, Matthew J. Heath

Dissertations, Master's Theses and Master's Reports - Open

Future power grids are envisioned to be serviced by heterogeneous arrangements of renewable energy sources. Due to their stochastic nature, energy storage distribution and management are pivotal in realizing microgrids serviced heavily by renewable energy assets. Identifying the required response characteristics to meet the operational requirements of a power grid are of great importance and must be illuminated in order to discern optimal hardware topologies. Hamiltonian Surface Shaping and Power Flow Control (HSSPFC) presents the tools to identify such characteristics. By using energy storage as actuation within the closed loop controller, the response requirements may be identified while providing a …