Michael Starke

AC vs. DC distribution: A loss comparison

Environmentally friendly technologies such as photovoltaics and fuel cells are DC sources. In the current power infrastructure, this necessitates converting the power supplied by these devices into AC for transmission and distribution which adds losses and complexity. The amount of DC loads in our buildings is ever-increasing with computers, monitors, and other electronics entering our workplaces and homes. This forces another conversion of the AC power to DC, adding further losses and complexity. This paper proposes the use of a DC distribution system. In this study, an equivalent AC and DC distribution system are compared in terms of efficiency.

Characteristics of wind turbine generators for wind power plants

This paper presents a summary of the most important characteristics of wind turbine generators applied in modern wind power plants. Various wind turbine generator designs, based on classification by machine type and speed control capabilities, are discussed along with their operational characteristics, voltage, reactive power, or power factor control capabilities, voltage ride-through characteristics, behavior during short circuits, and reactive power capabilities.

AC vs. DC distribution: Maximum transfer capability

Many studies comparing AC and DC systems have focused on efficiency, stability, and controllability, but have not compared the maximum transfer capability. In this paper, the maximum transfer capability of an AC system and two DC systems, one with two lines and another with three, is determined through the continuation power flow method and compared. The results reveal that significant gains can be achieved by moving to a DC system with three lines.

A method for modeling household occupant behavior to simulate residential energy consumption

This paper presents a statistical method for modeling the behavior of household occupants to estimate residential energy consumption. Using data gathered by the U.S. Census Bureau in the American Time Use Survey (ATUS), actions carried out by survey respondents are categorized into ten distinct activities. These activities are defined to correspond to the major energy consuming loads commonly found within the residential sector. Next, time varying minute resolution Markov chain based statistical models of different occupant types are developed. Using these behavioral models, individual occupants are simulated to show how an occupant interacts with the major residential energy consuming loads throughout the day. From these simulations, the minimum number of occupants, and consequently the minimum number of multiple occupant households, needing to be simulated to produce a statistically accurate representation of aggregate residential behavior can be determined. Finally, future work will involve the use of these occupant models along side residential load models to produce a high-resolution energy consumption profile and estimate the potential for demand response from residential loads.

Reactive power compensation for wind power plants

This technical paper provides the basic guidelines for the application of reactive compensation systems to be used as part of a wind power plant. A brief history of wind plant reactive compensation system is discussed, then the fundamental needs of why reactive compensation is required. The paper will then provide some alternatives for reactive compensation, how to size the reactive compensation, and finally some of the principles on how different compensation devices work.

Wind power plant substation and collector system redundancy, reliability, and economics

This paper presents basic guidelines on design considerations for wind power plant substation and collector system based on redundancy, reliability, and economics. Design considerations, although similar to utility substation and underground or overhead distribution systems, often include aspects not normally considered for those systems. This paper will highlight design considerations unique to wind power plant design comparing economic and reliability benefits among available design options. Power loss analysis in a typical wind power plant is explained. Finally, an overall economic analysis to be considered when designing a new wind power plant is presented.

Wind power plant collector system design considerations: IEEE PES wind plant collector system design working group

This paper presents a summary of the most important design considerations for wind power plants. Various considerations, including feeder topology, collector design, interconnect and NESC/NEC requirements, and design engineering studies are discussed.

A MATLAB based occupant driven dynamic model for predicting residential power demand

This paper presents a MATLAB based dynamic model for predicting residential power demand. Markov chain based occupant behavior models developed using data gathered by the U.S. Census Bureau in the American Time Use Survey (ATUS) are used in conjunction with models of the most common residential loads to predict residential power demand on a one-second time scale. First, the methods utilized for the modeling of each residential load are presented. Next, an explanation of how these load models are combined with occupant behavior models to predict residential power demand is given. Simulation results showing the overall contribution of each load to the overall residential sector power demand are shown for both winter and summer cases. Finally, future work will involve the use of this high-resolution dynamic residential model to estimate the potential for demand response from residential loads.

Modeling, controls, and applications of community energy storage systems with used EV/PHEV batteries

This study presents the modeling and controls of a community energy storage system composed of repurposed used electric or plug-in hybrid electric vehicle (EV/PHEV) battery packs. The expectation is that the vehicular batteries will be replaced with a fresh battery pack by the original equipment manufacturers (OEMs) once their performance (storage capacity and peak power capability) decrease to its 80% of the initial performance. Community energy storage (CES) systems can be a feasible application of these after vehicle batteries due to economic and environmental reasons. These batteries, if their power electronic interfaces are controlled properly, can perform many grid support applications or provide grid ancillary services as will be detailed in this study.

Load Participation in Ancillary Services Workshop Report

Developing load participation in ancillary services to the electric grid. Challenges: coordination among multiple entities, targeted R&D for market conditions and regulatory and policy environments.