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DOE OSTI2018

Method for calibration-free scanned-wavelength modulation spectroscopy for gas sensing

A method of calibration-free scanned-wavelength modulation spectroscopy (WMS) absorption sensing is provided by obtaining absorption lineshape measurements of a gas sample on a sensor using 1f-normalized WMS-2f where an injection current to an injection current-tunable diode laser (TDL) is modulated at a frequency f, where a wavelength modulation and an intensity modulation of the TDL are simultaneously generated, extracting using a numerical lock-in program and a low-pass filter appropriate band-width WMS-nf (n=1, 2, . . . ) signals, where the WMS-nf signals are harmonics of the f, determining a physical property of the gas sample according to ratios of the WMS-nf signals, determining the zero-absorption background using scanned-wavelength WMS, and determining non-absorption losses using at least two of the harmonics, where a need for a non-absorption baseline measurement is removed from measurements in environments where collision broadening has blended transition linewidths, where calibration free WMS measurements without knowledge of the transition linewidth is enabled.

47 OTHER INSTRUMENTATION↗

DOE OSTI2018

Integration of microinverter with photovoltaic module

Various technologies for integrating a microinverter with a photovoltaic module are disclosed. An alternating current photovoltaic (ACPV) module includes a photovoltaic module having a frame and a junction box including a direct current (DC) output connector, and a microinverter having a housing coupled to the frame and a DC input connector electrically mated with the DC output connector of the photovoltaic module.

Gilchrist, Phil↗

DOE OSTI2018

Coherent radar receiver that comprises a sigma delta modulator

Described herein are various technologies relating to processing a coherent signal. A receiver is configured to receive an analog signal, and process the analog signal to generate an input analog signal. The input analog signal has been modulated according to a suitable modulation sequence. A coherent signal sampler coherently samples the modulation sequence, and the result of such sampling is in turn used to demodulate the input analog signal. The resultant signal is then passed to a sigma delta modulator, where it is converted to digital form.

47 OTHER INSTRUMENTATION↗

DOE OSTI2019

The International Supply Chain and Manufacturing Costs for Photovoltaic Modules, and Project Economics of Systems Including Storage

This talk will highlight the most recent efforts from the National Renewable Energy Laboratory's (NREL) Strategic Energy Analysis Center (SEAC) to track solar PV manufacturing capacities and trade flows, bottom-up manufacturing costs, and project capital costs including storage. We will begin with an overview of the global PV supply chain and the 2019 benchmark input data used to inform NREL's crystalline silicon (c-Si) and thin film module manufacturing cost models. The accounting framework that we follow and that will be reviewed during this talk provides a methodology to prepare cost models in accordance with the Generally Accepted Accounting Principles (GAAP) and the International Financial Reporting Standards (IFRS). For the polysilicon, wafer, cell conversion, and module assembly steps of the c-Si supply chain, and for thin film modules, we will review input data and methods useful for calculating the costs of goods sold (COGS); research and development (R&D) expenses; and sales, general, and business administration (S, G, &A) expenses. This 2019 benchmark analysis is compiled for state-of-the-art polysilicon-to-module manufacturing across the globe. We will also provide an overview of opportunities for solar plus storage and show our 2018 benchmark bottom-up capital cost model results for utility-scale PV systems with battery storage.

14 SOLAR ENERGY↗

DOE OSTI2018

Edge reflector or refractor for bifacial solar module

One embodiment relates to a bifacial photovoltaic module having an edge reflector. The module includes a plurality of solar cells in an array, each solar cell having a front side and a back side. A reflector is configured on an edge of the array of solar cells, the first reflector being configured to reflect light onto the front side of a row of solar cells adjacent to the edge. Another embodiment relates to a method of reducing non-uniformity of power generation from a bifacial photovoltaic module. Electrical current produced from solar cells along at least one edge of the array is increased by using a reflective strip facing towards the front side of the solar cells along the edge. Another embodiment relates to a bifacial photovoltaic module having an edge refractor. Other embodiments and features are also disclosed.

Rose, Douglas H.↗

DOE OSTI2019

Development of a Marx Modulator for FNAL Linac

A Marx-topology modulator has been designed and developed at the Fermi National Accelerator Laboratory under the Proton Improvement Plan (PIP). This modulator replaces the previous triode hard-tube design, increasing reliability, lowering operational costs, and maintaining waveform accuracy. The Marx modulator supplies the anode of the 7835 VHF power triode tube with a 35 kV, 375 Amp, 460 μs pulse at 15 Hz. It consists of 54 individual Marx cells, each containing a 639 μF capacitor charged to 900 Volts, combined in series with IGBT switches to create the desired output waveform. This requires variable rise and fall times, flattening of capacitive droop, and feedforward beam loading compensation. All five 201.25 MHz RF systems have been upgraded to Marx modulators to ensure continued operation of the linear accelerator.

43 PARTICLE ACCELERATORS↗

DOE OSTI2019

Development of a Marx Modulator for FNAL Linac

A Marx-topology modulator has been designed and developed at the Fermi National Accelerator Laboratory under the Proton Improvement Plan (PIP). This modulator replaces the previous triode hard-tube design, increasing reliability, lowering operational costs, and maintaining waveform accuracy. The Marx modulator supplies the anode of the 7835 VHF power triode tube with a 35 kV, 375 Amp, 460 µs pulse at 15 Hz. It consists of 54 indi-vidual Marx cells, each containing a 639 µF capacitor charged to 900 Volts, combined in series with IGBT switches to create the desired output waveform. This requires variable rise and fall times, flattening of capaci-tive droop, and feedforward beam loading compensation. All five 201.25 MHz RF systems have been upgraded to Marx modulators to ensure continued operation of the linear accelerator.

43 PARTICLE ACCELERATORS↗

DOE OSTI2019

Structural frame and solar collector module

Solar collector modules and techniques for their construction are disclosed. In one aspect, a solar collector module includes a reflector and a three-dimensional structural frame that supports the reflector. The structural frame includes a set of primary structural shapes and a set of axial frame members connected between corners of the primary structural shapes forming helical paths for the transmission of torque from one end of the structural frame to the other. In another aspect, a method for assembling a solar collector module includes pre-assembling part of the module.

Eisinger, Joseph↗

DOE OSTI2016

Comparison between 1.7 kV SiC SJT and MOSFET Power Modules

Abstract— In this paper, a comprehensive evaluation work on 1.7 kV SiC Super Junction Transistor (SJT) power module and 1.7 kV SiC MOSFET power modules is presented. Both device static and dynamic performance is extracted and compared at wide device current range and temperature range. The data presented in this paper can be used as input for medium voltage power conversion system power transistor selection, gate drive design and system level thermal management design. Since the SiC SJT is a new power transistor with unique current driven mechanism. A dedicated section discusses the SiC SJT power module gate drive configuration and device false turn on suppress as well. In a summary, 1.7 kV SiC SJT shows superior on state conductivity, but similar switching performance compared to 1.7 kV SiC MOSFET power modules.

gate drive↗

DOE OSTI2020

Passive bias temperature compensation circuit module

A passive bias temperature compensation module for silicon photomultiplier, avalanche photodiodes and similar photodetectors that possess a moderately linear temperature coefficient of gain and that may be compensated by varying an applied bias voltage. The module includes an electrical circuit and a method for determining component values to provide a constant voltage source to stabilize the gain of one or more photodetector devices. A temperature sensor in the module is held in close thermal contact with the photodetector and a filter capacitor is electrically close to the photodetector. The module is based on the concept of temperature sensitive voltage division which is applicable to situations in which large numbers of photodetectors must be gain-compensated for temperature variations over a wide range while maintaining excellent gain matching. The passive bias temperature compensation method enables multiple photodetectors to share a single constant voltage supply without loss of matching performance.

42 ENGINEERING↗

DOE OSTI2020

Constraining the Charge-Sign and Rigidity-Dependence of Solar Modulation

Our ability to identify the sources of cosmic rays and understand how these particles propagate through the interstellar medium is hindered by the combined effects of the solar wind and its embedded magnetic field, collectively known as solar modulation. In this paper, we build upon our previous work to model and constrain the effects of solar modulation on the cosmic-ray spectrum, using data from AMS-02 and BESS Polar II collected between 2007 and 2012, during which the heliospheric magnetic field was in a state of negative polarity. Our model uses measurements of the heliospheric magnetic field and the tilt angle of the heliospheric current sheet to accurately predict the effects of solar modulation as a function of time, charge, and rigidity. By incorporating data from a period of negative polarity, we have been able to robustly observe and constrain the charge-dependent effects of solar modulation.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2020

Method and apparatus of surface-incident, plasmon-enhanced multiple quantum well modulators and optical coupling thereon

An optical interconnect system has first and second waveguides each with wedge-shaped cross-section at a first end, disposed over an optical modulator. The optical modulator is a surface-plasmon multi quantum well (SP-MQW) modulator, the first waveguide an input waveguide and the second waveguide configured an output waveguide. In embodiments the SP-MQW modulator has multiple semiconductor layers disposed atop a lower metal layer between 10 and 300 nanometers thick and configured such that incident light is reflected at the lower metal layer unless a voltage is applied to the semiconductor layers, when incident light is coupled into a surface plasmon mode in the lower metal layer.

42 ENGINEERING↗

DOE OSTI2020

Field Reliability of Glass/Glass Modules

A review of literature indicates that there will be a 20% increase in utilization of glass/glass PV modules by 2023. Common degradation modes reported in literature of glass/glass modules are: Encapsulant delamination, Encapsulant browning, corrosion and glass cracks. There is a strong need to investigate the reliability of glass/glass modules in detail to identify and overcome any potential failures in the future constructions. This work presents a preliminary literature review on the reliability of old generation glass/glass modules in the field.

14 SOLAR ENERGY↗

DOE OSTI2021

Systems and methods for reworking shingled solar cell modules

A high efficiency configuration for a solar cell module comprises solar cells arranged in a shingled manner to form super cells, which may be arranged to efficiently use the area of the solar module, reduce series resistance, and increase module efficiency. Removing a defective solar cell from a super cell may be difficult, however. It may therefore be advantageous to bypass defective solar cells in a super cell rather than remove and replace them. A bypass conductor may be applied to the rear surface of the super cell to bypass one or more defective solar cells in a super cell or in a solar module comprising super cells.

Caswell, Nathaniel Alexis↗

DOE OSTI2021

Integration of microinverter with photovoltaic module

Gilchrist, Phil↗

DOE OSTI2023

Scintillation light detection performance for the DUNE ND-LAr 2 × 2 modules

The Deep Underground Neutrino Experiment (DUNE) will be using a liquid argon time projection chamber (LAr TPC) with optically separated modules in the Near Detector (ND) complex. A prototype experiment, DUNE ND-LAr 2 × 2, is composed of four test modules. They detect ionization charge through a pixel-based readout and scintillation light through fibers in light collection modules and light traps called ArCLights. The light detection performance for two modules of DUNE ND-LAr 2 × 2 that took cosmic ray data at the University of Bern is shown. We present further the role of the 2 × 2 prototype in DUNE and how it is used to demonstrate the reconstruction capabilities of its light detectors in terms of energy thresholds and timing resolution.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2023

Rear-Side Irradiance Simulation of Field PV Modules: Preprint

Assessing the durability of photovoltaic (PV) module backsheet is critical to increasing module lifetime. Historically, laboratory-based accelerated testing has insufficient in predicting large-scale failures of commercial polymeric materials. Additionally, there is growing concern that standard condition tests do not reflect non-uniformities in field exposure, and that certain modules experience more severe degradation due to their location. Anisotropy in field exposures is installation dependent and reflects different levels of exposure to irradiance due to mounting geometry, ground surface albedo, and climatic zone. "Bificial Radiance" [1], simulates the amount of reflected irradiance on the Polyethylene Naphthalate (PEN) backsheet of a PV array located in Maryland. In our work, site specific weather data are gathered for the entire length of exposure for the modules. The total full-spectrum dose for the incident irradiance on the backsheet was then determined. The simulation results are integrated with historical field survey data to better understand realworld outdoor degradation.

backsheet↗

DOE OSTI2023

Stabilizers for a vehicle cooling module

A stabilizing arrangement of a cooling system module of a vehicle includes stabilizer pins attached to the vehicle cooling system module. Stabilizer slots are incorporated into a component of the chassis of the vehicle, such as a frame extender. The stabilizer slots may be formed as an upwards opening U-shape. Bushings are attached to the stabilizer pins. The stabilizer pins and bushings extend laterally into and engage with the stabilizer slots. Upon installation, the stabilizer pins and bushings are aligned with the stabilizer slots as the cooling system module is lowered onto the ISO mounts. The stabilizer pins and bushings slide vertically downwards into the stabilizer slots as the cooling system module is lowered into place. The simpler stabilizer pins, bushings, and stabilizer slots thereby take the place of expensive, time consuming, complex, labor intensive, and space consuming stay rod arrangements.

Wu, Shouhao↗