Publications

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Field tests of air-copper arcs were completed at a high-voltage, photovoltaic power plant using a simplified, 'arc-in-a-box' geometry to study dc arc-faults. Copper electrodes, 12.7 mm in diameter, were arranged in three configurations and an arc was initiated using < 700 VDCwith applied energy varying from 40-3900 kJ. Constitutive modeling of the arc-discharge predicts arc temperatures much greater than 1000 K. Two diagnostic techniques were fielded to characterize the spectral and thermal emission. Optical emission spectroscopy determined the time-resolved and mean arc temperatures were approximately T_{mean}= 7500 with standard deviations of ± 600 K, and infrared (IR) imaging mapped the mean temperature field, T_{mean}=1500\ \mathrm{K}, of the arc-heated environment.

Photovoltaic (PV) system certifications and codes have been modified to allow 1,500 V products onto the market which facilitate the plant engineering, procurement, and construction; however, the codes inadequately address the increased hazards to people and equipment in a high-voltage, photovoltaic plant that emanate from the rapid release of thermal energy, pressure waves, and electromagnetic interference of an arc-fault event. Existing calculations can contradict one another and are rooted in theory, not in physical testing. For this investigation, a localized arc-plasma model for a cylindrical geometry arc was developed from coupled electrodynamic, thermodynamic, and fluid mechanics equations, that were convolved together based on previous arc-discharge models [1]. The model was developed to assess incident energy, used for determining appropriate personal protective equipment (PPE), as a function of spark-gap current. To validate the model, preliminary experiments were performed at Sandia National Laboratories (SNL) with voltage levels as high as 1,500 V. Further utility-scale PV experiments were also conducted with current levels as high as 1,607 A to provide further data. Arc-stability, plasma column spectral features and radiative temperature rise were all evaluated during each respective test to provide radiated power values for validation. Overall preliminary results suggest a logarithmic increase in radiative power between 250 and 2800 W/cm for a current increase from 100 to 300 A.

Field tests of air-copper arcs were completed at a high-voltage, photovoltaic power plant using a simplified, 'arc-in-a-box' geometry to study dc arc-faults. Copper electrodes, 12.7 mm in diameter, were arranged in three configurations and an arc was initiated using < 700 VDCwith applied energy varying from 40-3900 kJ. Constitutive modeling of the arc-discharge predicts arc temperatures much greater than 1000 K. Two diagnostic techniques were fielded to characterize the spectral and thermal emission. Optical emission spectroscopy determined the time-resolved and mean arc temperatures were approximately T_{mean}= 7500 with standard deviations of ± 600 K, and infrared (IR) imaging mapped the mean temperature field, T_{mean}=1500\ \mathrm{K}, of the arc-heated environment.

Photovoltaic (PV) system certifications and codes have been modified to allow 1,500 V products onto the market which facilitate the plant engineering, procurement, and construction; however, the codes inadequately address the increased hazards to people and equipment in a high-voltage, photovoltaic plant that emanate from the rapid release of thermal energy, pressure waves, and electromagnetic interference of an arc-fault event. Existing calculations can contradict one another and are rooted in theory, not in physical testing. For this investigation, a localized arc-plasma model for a cylindrical geometry arc was developed from coupled electrodynamic, thermodynamic, and fluid mechanics equations, that were convolved together based on previous arc-discharge models [1]. The model was developed to assess incident energy, used for determining appropriate personal protective equipment (PPE), as a function of spark-gap current. To validate the model, preliminary experiments were performed at Sandia National Laboratories (SNL) with voltage levels as high as 1,500 V. Further utility-scale PV experiments were also conducted with current levels as high as 1,607 A to provide further data. Arc-stability, plasma column spectral features and radiative temperature rise were all evaluated during each respective test to provide radiated power values for validation. Overall preliminary results suggest a logarithmic increase in radiative power between 250 and 2800 W/cm for a current increase from 100 to 300 A.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.