PXI Instrumentation Research Articles

An automated environment for hardware testing using PXI instrumentation and LabVIEW software

An automated environment for hardware testing using PXI instrumentation and LabVIEW software

Development of a New Time Resolved Irradiance Uniformity Mapper at Spasolab

Irradiance uniformity mapping of solar simulators is a key characterization required for performing accurate solar cell electrical performance tests, alongside spectrum matching and stability. Within photovoltaic space standards such as [1] and [2], uniformity mapping is specified to verify the solar simulator nonconformance class. However, uniformity mappers are a relevant tool for solar simulator manufacturers as well as for space solar cell testing facilities, aiding to adjust test plane irradiance uniformity after maintenance, lamp replacement or on a more analytic approach, applying correction factors to the test plane. Thus, it is desirable to have a tool that allows for easier and faster acquisition of irradiance uniformity maps.This paper presents a time-resolved uniformity mapper developed at Spasolab based on two main premises: easy adaptability to different solar simulators and versatility in terms of irradiance operation range, extended up to 2 AM0. A modular two-stage design features independent bias PCB’s per each photodiode that allow for easy sensor swapping or different biasing for future sensor replacements. A new type of photodiode active biasing is also presented, with the main feature of being capable of switching on the bias voltage only during the acquisition process, hence reducing self-heating. Ad-hoc software developed in LabVIEW and PXI instrumentation enable the system to have different acquisition modes further expanding the irradiance range to be tested without risking hazard to the system due to overheating. Finally, outdoor calibration method and results for the system are also presented.

Focus on materials, semiconductors, vacuum, and cryogenics

Focus on materials, semiconductors, vacuum, and cryogenics

The Test System of PXI-Based Aeronautic Equipment

By analyzing the interface characteristics and test requirements of certain aeronautic equipment, using PXI instrument as test platform, integrated using SPIB instrument, virtual instrument, simulation technologies, independent developed video output collection equipment, SRU testing equipment modules and other hardware device, developed integrated automatic test equipment which based on PXI and GPIB bus instrument technology, provide airborne work environment for weapons, instrument, electrical, communication, navigation, identification, reactance systems airborne LRU, automatic complete the control, incentive, performance and function test of LRU.

The Test System of PXI-Based Aeronautic Equipment

By analyzing the interface characteristics and test requirements of certain aeronautic equipment, using PXI instrument as test platform, integrated using SPIB instrument, virtual instrument, simulation technologies, independent developed video output collection equipment, SRU testing equipment modules and other hardware device, developed integrated automatic test equipment which based on PXI and GPIB bus instrument technology, provide airborne work environment for weapons, instrument, electrical, communication, navigation, identification, reactance systems airborne LRU, automatic complete the control, incentive, performance and function test of LRU.

Filterscopes: Spectral line monitors for long-pulse plasma devices

A photomultiplier (PMT)-based diagnostic system for monitoring spectral lines along multiple viewchords, named the "Filterscope" [R. J. Colchin et al., Rev. Sci. Instrum. 74, 2068 (2003)], is currently in use at the DIII-D, NSTX, and CDX-U fusion plasma devices in the US, and has been installed at the KSTAR device in Korea. This diagnostic has recently been upgraded for application to long-pulse devices, such as KSTAR, EAST in China, and the future ITER in France. A new data acquisition system, employing the PXI instrumentation platform with an embedded Windows microprocessor controller, can simultaneously record up to 72 channels at 100 kHz sampling rates for plasma periods lasting up to 20 min. Based on the average signal level during an adjustable time interval (100 ms in the present DIII-D implementation), the controller digitally adjusts PMT dynode voltage throughout the course of a discharge, thereby maintaining the output signals at a level where they are neither saturated nor dominated by digitizer noise. The new system's ability to accommodate large variations in source strength, discharge to discharge and within a single discharge, has proved particularly valuable during DIII-D operations, since changes between top, bottom, and double-null divertor magnetic configurations lead to large temporal variations in signal brightness.