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Implementation of Temporal Parallelization for Rapid Quasi-Static Time-Series (QSTS) Simulations

Conference Record of the IEEE Photovoltaic Specialists Conference

Azzolini, Joseph A.; Reno, Matthew J.; Montenegro, Davis

Quasi-static time-series (QSTS) analysis of distribution systems can provide critical information about the potential impacts of high penetrations of distributed and renewable resources, like solar photovoltaic systems. However, running high-resolution yearlong QSTS simulations of large distribution feeders can be prohibitively burdensome due to long computation times. Temporal parallelization of QSTS simulations is one possible solution to overcome this obstacle. QSTS simulations can be divided into multiple sections, e.g. into four equal parts of the year, and solved simultaneously with parallel computing. The challenge is that each time the simulation is divided, error is introduced. This paper presents various initialization methods for reducing the error associated with temporal parallelization of QSTS simulations and characterizes performance across multiple distribution circuits and several different computers with varying architectures.

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TYPE Conference Poster YEAR 2019
DOIOSTIScopus

Single Diode Parameter Extraction from In-Field Photovoltaic I-V Curves on a Single Board Computer

Conference Record of the IEEE Photovoltaic Specialists Conference

Jones, Christian B.; Hansen, Clifford

In this paper, we present a new, light-weight approach for extracting the five single diode parameters (IL, Io, RS, RSH, and nNsVt) for advanced, in-field monitoring of in situ current and voltage (I-V) tracing devices. The proposed procedure uses individual I-V curves, and does not require the irradiance or module temperature measurement to calculate the parameters. It is suitable for operation on a small, single board computer at the point of I-V curve measurement. This allows for analysis to occur in the field, and eliminates the need to transfer large amounts of data to centralized databases. Observers can receive alerts directly from the in-field devices based on the extraction, and analysis of the commonly used single diode equivalent model parameters. This paper defines the approach and evaluates its accuracy by subjecting it to I-V curves with known parameters. Its performance is defined using actual I-V curves generated from an in situ scanning devices installed within an actual photovoltaic production field. The algorithm is able to operate at a high accuracy for multiple module types and performed well on actual curves extracted in the field.

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TYPE Conference Poster YEAR 2019
DOIOSTIScopus

Vacuum Insulator Flashover of Ultra High Vacuum Compatible Insulators

IEEE International Pulsed Power Conference

Leckbee, Joshua; Simpson, Sean; Ziska, Derek; Bui, Bill

High voltage vacuum systems with stringent vacuum requirements are often designed with ceramic insulators which have low flashover strength. In this paper, we report on experimental results comparing pulsed high voltage flashover of Rexolite®(cross-linked polystyrene), a pulsed power industry standard vacuum insulator, to Kel-F® (polyclorotrifluoroethylene), a plastic with significantly lower vacuum outgassing. Our results show similar surface flashover results with the two materials, with both exhibiting large spread in flashover electric field. The average electric field for flashover of each material agree well with predictions based on previously published results.

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TYPE Conference Poster YEAR 2019
DOIOSTIScopus

Single Diode Parameter Extraction from In-Field Photovoltaic I-V Curves on a Single Board Computer

Conference Record of the IEEE Photovoltaic Specialists Conference

Jones, Christian B.; Hansen, Clifford

In this paper, we present a new, light-weight approach for extracting the five single diode parameters (IL, Io, RS, RSH, and nNsVt) for advanced, in-field monitoring of in situ current and voltage (I-V) tracing devices. The proposed procedure uses individual I-V curves, and does not require the irradiance or module temperature measurement to calculate the parameters. It is suitable for operation on a small, single board computer at the point of I-V curve measurement. This allows for analysis to occur in the field, and eliminates the need to transfer large amounts of data to centralized databases. Observers can receive alerts directly from the in-field devices based on the extraction, and analysis of the commonly used single diode equivalent model parameters. This paper defines the approach and evaluates its accuracy by subjecting it to I-V curves with known parameters. Its performance is defined using actual I-V curves generated from an in situ scanning devices installed within an actual photovoltaic production field. The algorithm is able to operate at a high accuracy for multiple module types and performed well on actual curves extracted in the field.

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TYPE Conference Poster YEAR 2019
DOIOSTIScopus

Electro-Optical Measurement of Electric Fields for Pulsed Power Systems

IEEE International Pulsed Power Conference

Owens, Israel J.; Grabowski, Theodore C.; Joseph, N.; Coffey, Sean; Ulmen, Ben; Kirschner, Debra; Rainwater, K.; Struve, Kenneth

The electric field strength between the cathode and anode (i.e., the voltage) of a pulsed power machine is one of the most important operating parameters of the device. However, to date, accurate and precise voltage measurements on these high energy pulsed power systems have proved difficult if not virtually impossible to perform. In many cases, the measurements to be performed take place in an environment cluttered with electromagnetic interference (EMI), radio frequency interference (RFI), and electron pollution, and there is the potential for electrical discharge (or arcing), there is limited physical access, or the measurement area is deemed unsuitable due to radiation safety concerns. We report on an electro-optical-based approach to measuring strong, narrow-pulse-width electric fields that requires no interfering metallic probes or components to disturb the field to be measured. Here we focus on device theory, operating parameters and a laboratory experiment.

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TYPE Conference Poster YEAR 2019
DOIOSTIScopus

Geographic Assessment of Photovoltaic Module Environmental Degradation Stressors

Conference Record of the IEEE Photovoltaic Specialists Conference

Jones, Christian B.; Karin, Todd; Jain, Anubhav; Hobbs, William B.; Libby, Cara

Environmental stress can degrade photovoltiac (PV) modules. We perform a literature search to identify models that estimate the damage caused by exposure to various environmental stressors, including temperature, radiation, and humidity. The weather-related variables, including ambient temperature, irradiance and humidity are calculated using the Global Land Data Assimilation System (GLDAS). The analysis also calculated degradation-model stressors, module temperature, plane of array irradiance, and relative humidity and compared these PV-specific variables to identify correlations and the translation required to represent the stressor accurately. The results show that global horizontal (GHI) irradiance can be used instead of plane-of-array irradiance to represent radiation dose. However, module temperature can be significantly different from ambient temperatures and specific humidity is significantly different from relative humidity.

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TYPE Conference Poster YEAR 2019
DOIOSTIScopus

Grid-forming Inverter Experimental Testing of Fault Current Contributions

Conference Record of the IEEE Photovoltaic Specialists Conference

Gurule, Nicholas S.; Hernandez-Alvidrez, Javier; Reno, Matthew J.; Summers, Adam; Gonzalez, Sigifredo; Flicker, Jack D.

Historically, photovoltaic inverters have been grid-following controlled, but with increasing penetrations of inverter-based generation on the grid, grid-forming inverters (GFMI) are gaining interest. GFMIs can also be used in microgrids that require the ability to interact and operate with the grid (grid-tied), or to operate autonomously (islanded) while supplying their corresponding loads. This approach can substantially improve the response of the grid to severe contingencies such as hurricanes, or to high load demands. During islanded conditions, GFMIs play an important role on dictating the system's voltage and frequency the same way as synchronous generators do in large interconnected systems. For this reason, it is important to understand the behavior of such grid-forming inverters under fault scenarios. This paper focuses on testing different commercially available grid-forming inverters under fault conditions.

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TYPE Conference Poster YEAR 2019
DOIOSTIScopus

Large Acoustoelectric Effect in Wafer Bonded Indium Gallium Arsenide / Lithium Niobate Heterostructure Augmented by Novel Gate Control

2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems and Eurosensors XXXIII, TRANSDUCERS 2019 and EUROSENSORS XXXIII

Siddiqui, Aleem; Hackett, Lisa A.P.; Dominguez, Daniel; Tauke-Pedretti, Anna; Friedmann, Thomas A.; Peake, Gregory M.; Miller, M.; Douglas, James K.; Eichenfield, Matt

This paper demonstrates a monolithic surface acoustic wave amplifier fabricated by state-of-the-art heterogenous integration of a IH-V InGaAs-based epitaxial material stack and LiNb03. Due to the superior properties of the materials employed, we observe electron gain and also non-reciprocal gain in excess of 30dB with reduced power consumption. Additionally, we present a framework for performance optimization as a function of material parameters for a targeted gain. This platform enables further advances in active and non-reciprocal piezoelectric acoustic devices.

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TYPE Conference Poster YEAR 2019
DOIOSTIScopus

EXPERIMENTAL RESULTS FROM THE 1.2 MA 2.2 m DIAMETER LINEAR TRANSFORMER DRIVER AT SANDIA NATIONAL LABS

Douglass, Jonathan; Hutsel, Brian T.; Leckbee, Joshua J.; Stoltzfus, Brian S.; Wisher, Matthew L.; Savage, Mark E.; Stygar, William A.; Breden, Eric W.; Calhoun, Jacob D.; Cuneo, Michael E.; Jaramillo, Deanna M.; Johns, Owen; Jones, Michael; Lucero, Diego; Moore, James M.; Sceiford, M.E.; Kiefer, Mark L.; Mulville, Thomas D.; Sullivan, Michael A.; Hohlfelder, Robert J.

Abstract not provided.

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TYPE Conference Poster YEAR 2019
DOIOSTI
Results 23101–23200 of 99,299
Results 23101–23200 of 99,299