In a typical data center, less than half the energy consumed is delivered to compute load, with rest lost in power conversion, distribution and cooling. Traditionally at 400/480 V AC centers -48 DC telco facilities. Higher voltage has been proposed as an efficient option for both types of facilities, this paper presents analytical evaluation several center delivery architectures over range loads, showing that 400 facility-level most efficient. The equipment required support such architecture...

This paper presents a method for minimizing the cost of vehicle battery charging given variable electricity costs while also accounting estimated degradation using simplified lithium-ion lifetime model. The simple model, developed and presented here, estimates both energy capacity fade power includes effects due to temperature, state charge profile, daily depth discharge. model has been validated by comparison with detailed at National Renewable Energy Laboratory, which in turn through...

The problem of modeling and stochastic optimization for home energy management is considered. Several different types load classes are discussed, including heating, ventilation, air conditioning unit, plug-in hybrid electric vehicle, deferrable loads such as washer dryer. A first-order thermal dynamic model extracted validated using real measurements collected over an eight months time span. mixed integer multi-time scale formulated the scheduling characteristics. predictive control based...

This paper presents a method for minimizing the cost of electric vehicle (EV) charging given variable electricity costs while also accounting estimated battery degradation using simplified lithium-ion lifetime model. The simple model, developed and presented here, estimates both energy capacity fade power due to temperature, state charge profile, daily depth discharge. model has been validated by comparison with detailed [6], which in turn through experimental data. runs quickly MATLAB...

Approximately 100 million singlefamily homes in the United States account for 36% of electricity load, and often they determine peak system especially on hot summer days when residential air-conditioning use is high. Traditional building power profiles are changing. Currently, there an increased energy-efficient materials designs, which decreases loads. In addition, adoption rooftop solar photovoltaic (PV), leads to bidirectional flow significant ramps as PV output late afternoon. Building...

Residential customers use more than one-quarter of the electricity in world. Optimally managing home energy consumption is an effective way easing operational challenges facing electric grid with increasing solar photovoltaics (PV). This paper studies impact future proliferation management systems (HEMS) presence PV on large-scale distribution systems. First, we present a stochastic HEMS model that minimizes residential customers' thermal discomfort and costs under uncertainty. The schedules...

To achieve high-power density in power supplies, it is desirable to minimize the physical size of energy storage capacitor. The capacitance determined by requirement for line outage ride-through and also ripple current handling capability Interleaving well known as an effective method reduce capacitor cases where considerations dominate, could size. This paper presents a methodology calculate current, both single phase <i xmlns:mml="http://www.w3.org/1998/Math/MathML"...

Microgrids can provide economic benefits, and those benefits be maximized through intelligent control. This paper applies a fast reliable linear programming (LP) approach to the dispatch of grid-tied microgrids containing any or all following resources: conventional generators, energy storage, demand response resources, non-dispatchable resources (e.g. solar wind). The proposed method minimizes cost operate microgrid while meeting various resource constraints. Forecast load renewable power...

This paper presents a test bed that utilities, vendors, and researchers can use to evaluate the performance of existing emerging advanced distribution management systems (ADMS) or specific applications such systems. The provides realistic laboratory setting, including detailed modeling power system, controller and/or hardware, industry-standard communication protocols. further represent current state utility's system anticipated with increased penetrations distributed energy resources, as...

This paper develops an integrated synchronization control technique for a grid-forming inverter operating within microgrid that can improve the microgrid's transients during transition operation. includes disconnection and reconnection control. The simulation results show developed works effectively to smooth angle change of Thus, are significantly improved compared case without

The problem of scheduling and control appliances for Home Energy Management (HEM) is considered. A multi-time scale multi-stage stochastic optimization framework proposed the Heating, Ventilation, Air Conditioning (HVAC) unit, charging Plug-in Hybrid Electric Vehicle (PHEV), deferrable load such as washer/dryer operations. Formulated a constrained that incorporates thermal dynamics, temperature measurements, real time pricing signal, model predictive algorithm minimizes customer's discomfort...

The problem of modeling and control for Home Energy Management (HEM) is considered. A first order thermal dynamic model considered its parameters are extracted using real measurements over a period three summer months. identified validated separate data sets. shows certain nonstationarity non-Gaussianity. However, local approximations stationary shown to have relatively small prediction errors. then used developing multi-scale multi-stage stochastic optimization framework the Heating,...

The limited lifetime, high cost, and large size of current lithium ion batteries are some the primary obstacles to wider adoption electric vehicles plug-in hybrid vehicles. Simulations presented in this paper predict that Li-ion battery life can be extended through intelligent charging, especially when predictions next-day energy needs used charge only as needed. As-needed charging minimizes degradation by minimizing time spent at state-of-charge. Preliminary results here indicate a vehicle...

Microgrids have long been deployed to provide power customers in remote areas as well critical industrial and military loads. Today, they are also being proposed grid-interactive solutions for energy-resilient communities. Such microgrids will spend most of the time operating while synchronized with surrounding utility grid but be capable separating during contingency periods due storms or temporary disturbances such local faults. Properly designed grid-integrated can flexibility,...

Power hardware-in-the-loop (PHIL) simulation, where actual hardware under text is coupled with a real-time digital model in closed loop, powerful tool for analyzing new methods of control emerging distributed power systems. However, without careful design and compensation the interface between simulated systems, PHIL simulations may exhibit instability modeling inaccuracies. This paper addresses issues that arise simulation battery inverter interfaced distribution feeder. Both stability...

This paper proposes a stochastic, multi-objective optimization model within Model Predictive Control (MPC) framework, to determine the optimal operational schedules of residential appliances operating in presence renewable energy source (RES). The objective function minimizes weighted sum discomfort, cost, total and peak electricity consumption, carbon footprint. A heuristic method is developed for combining different components. proposed stochastic utilizes Monte Carlo simulation (MCS)...

Energy systems integration combines energy carriers, including electricity, with infrastructures, to maximize efficiency and minimize waste. In order study at a variety of physical scales---from individual buildings distribution systems---interconnected through these NREL is developing an Integrated System Model (IESM), initial focus on the electricity system. Today's grid most complex system ever built---and future likely be even more because it will incorporate distributed resources (DERs)...

This paper reports on tools and methodologies developed to study the impact of adding rooftop photovoltaic (PV) systems, with without ability provide reactive power, primary voltage profile a distribution feeder. Simulation results are provided from SDG&E utility The simulation model feeder was built in OpenDSS verified by comparing simulated voltages field measurements. First, all PV inverters were set operate at unity power factor, analyzed. Then simulations conducted support activated for...

Dynamic tariffs such as time-of-use (TOU) were introduced to motivate consumers change the operation of their behind-the-meter (BTM) resources reduce power consumption during peak demand times. Recently, export rates have been implemented that reimburse for electricity exported grid at a rate less than retail reverse flow in distribution systems with high photovoltaic penetrations. Export are expected be employed more widely, and therefore it is important understand impact on consumers, BTM...

Many have proposed that responsive load provided by distributed energy resources (DERs) and demand response (DR) are an option to provide flexibility the grid especially distribution feeders. However, because involves a complex interplay between tariffs DER DR technologies, it is challenging test evaluate options without negatively impacting customers. This paper describes hardware-in-the-loop (HIL) simulation system has been developed reduce cost impacts of evaluating effect advanced...