Controls and Control Theory Commons^™

Power System Dynamic Control And Performance Improvement Based On Reinforcement Learning, Wei Gao

Electronic Theses and Dissertations

This dissertation investigates the feasibility and effectiveness of using Reinforcement Learning (RL) techniques for power system dynamic control, particularly voltage and frequency control. The conventional control strategies used in power systems are complex and time-consuming due to the complicated high-order nonlinearities of the system. RL, which is a type of neural network-based technique, has shown promise in solving these complex problems by fitting any nonlinear system with the proper network structure.

The proposed RL algorithm, called Guided Surrogate Gradient-based Evolution Strategy (GSES) determines the weights of the policy (which generates the action for our control reference signal) without back-propagation process …

Nonlinear Control And Observation Of Full-Variable Speed Wind Turbine Systems., Nicholas Hawkins

Electronic Theses and Dissertations

With increasing concern for the environmental effects of power generation from fossil fuels, wind energy is a competitive source for electrical power with higher efficiency than other clean sources. However, the nature of this power source makes controlling wind turbines difficult. The variability of wind as a source either requires highly accurate measurement equipment or sophisticated mathematical alternatives. In addition to the unknown quantities of the weather itself, the efficiency of power capture at the turbine blades is highly nonlinear in nature and difficult to ascertain. The ability of either determine these troublesome quantities, or control the system despite ignorance …

A Four-Port Bidirectional Dc-Dc Converter For Renewable Energy System And Microgrid, Xia Du

All Graduate Theses, Dissertations, and Other Capstone Projects

Renewable energy has nowadays become important in electrical power applications. Power converters play an important role in integrating these distributed energy sources. However, due to their intermittence characteristics, e.g., the output power provided by the PV and wind turbine is not stable, either an energy storage system will be used or microgrid is formed between the main grid and the sources. To integrate these renewable energy sources and manage the power flow, a multiport converter is preferred because it is highly beneficial and cost-efficiently than the traditional solution that using multiple individual power converter for each source. This thesis proposed …

Applications Of Complex Network Analysis In Electric Power Systems, Mahmoud Saleh, Yusef Esa, Ahmed Mohamed

Publications and Research

This paper provides a review of the research conducted on complex network analysis (CNA) in electric power systems. Moreover, a new approach is presented to find optimal locations for microgrids (MGs) in electric distribution systems (EDS) utilizing complex network analysis. The optimal placement in this paper points to the location that will result in enhanced grid resilience, reduced power losses and line loading, better voltage stability, and a supply to critical loads during a blackout. The criteria used to point out the optimal placement of the MGs were predicated on the centrality analysis selected from the complex network theory, the …

Communication Based Control For Dc Microgrids, Mahmoud S. Saleh, Yusef Esa, Ahmed Mohamed

Publications and Research

Centralized communication-based control is one of the main methods that can be implemented to achieve autonomous advanced energy management capabilities in DC microgrids. However, its major limitation is the fact that communication bandwidth and computation resources are limited in practical applications. This can be often improved by avoiding redundant communications and complex computations. In this paper, an autonomous communication-based hybrid state/event driven control scheme is proposed. This control scheme is hierarchical and heuristic, such that on the primary control level, it encompasses state-driven local controllers, and on the secondary control level, an event-driven MG centralized controller (MGCC) is used. This …

Robust Power Interface For Smart Grid With Renewable Energy Source-To-Grid Functionality, Bohyun Ahn

All Graduate Theses, Dissertations, and Other Capstone Projects

Many renewable energy companies design wind turbine generators, solar panels, or electrical car batteries with different specifications according to their management philosophy. And typical commercial power converters are not universally designed for all different types of renewable energy systems. Because of this lack of flexibility and interoperability, a universal and scalable smart grid power converter design is desirable. Designing a robust controlled bi-directional power converter is the motivation for this thesis as the first step to develop a more universal converter topology connecting renewable energy sources and the electrical smart-grid of the future.

Renewable energy such as wind or solar …

A Novel Power Sharing Control Method For Distributed Generators In Dc Networks, Christina James

Electrical & Computer Engineering Theses & Dissertations

The power sharing control method is a desirable solution to integrate multiple renewable energy generators into the grid and to keep them working synchronously. Power sharing control between different distributed generators is an important consideration for the stabilized operation of the power grid network. In this thesis work, a novel method is used with the concept of droop control technique and is designed to control power from each individual generator in DC network particularly. The proposed power sharing control method can be widely applied to grid connected network and to islanded power grid network for obtaining high efficiency of power …

Impact Of Clustering Microgrids On Their Stability And Resilience During Blackouts, Mahmoud S. Saleh, Ammar Althaibani, Yusef Esa, Yassine Mhandi, Ahmed Mohamed

Publications and Research

In this paper, the impact of clustering multiple microgrids during blackouts, on their stability and supply availability, will be investigated. Microgrids have the capability of satisfying their emergency loads during blackouts. However, distributed energy resources (DERs)-dominated microgrids are affected by the uncertainty of their input energy supply, e.g. impact of solar irradiance on photovoltaic (PV) output. Moreover, an individual islanded microgrid is prone to instability issues due to large sudden load/generation changes. In order to increase the supply security, and enhance system stability, we propose to use the existing distribution grid infrastructure, if applicable, during blackouts to form microgrid clusters. …

Hybrid Power System Intelligent Operation And Protection Involving Plug-In Electric Vehicles, Tan Ma

FIU Electronic Theses and Dissertations

Two key solutions to reduce the greenhouse gas emissions and increase the overall energy efficiency are to maximize the utilization of renewable energy resources (RERs) to generate energy for load consumption and to shift to low or zero emission plug-in electric vehicles (PEVs) for transportation. The present U.S. aging and overburdened power grid infrastructure is under a tremendous pressure to handle the issues involved in penetration of RERS and PEVs. The future power grid should be designed with for the effective utilization of distributed RERs and distributed generations to intelligently respond to varying customer demand including PEVs with high level …