Hello all,
We have an issue at the laboratory on how to acquire real-time analog data (high voltage ~10kV and current ~70 kA) into digital, in an environment with electro-magnetic interference.
In order to get rid of the EMI one could transform analog to light. However, you get inaccuracies as a result of the transformation analog-light-analog-digital.
I wonder, if any lab has experienced the same problem. If so, how did you resolve it? Also, are there any COTS data acquisition systems for measuring high voltage/current? After a brief Google search, I have stumbled upon the NI PXI Express Optical Sensor Interrogator. One of our labs is currently using it. However, it measures temperature/strain only.
There's little we have come up with so far:
1. Current transducer. We are considering the NXCT F3 Optical Current Sensor (by Alstom). It does provide the required accuracy and is insensitive to EMI. Although they claim it's IEC 61850 compliant, I couldn't find any info on how to embed it in a control system.
2. As a voltage transducer we can take high-precision voltage dividers and are thinking of designing custom-made analog-to-light converters (transmitter) and light-to-digital receiver.
The total number of sensors/signals to measure is on the order of 80-100. Since this is intended to be used in the ITER tokamak, there are constraints on the instrumentation/software to be used. In particular, it is proposed to use National Instuments architecture, together with the CODAC framework. Aslo, it has to be IEEE-1588 compliant (TCN).
Any insights on the matter would be much appreciated!
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Best regards,
Pavel Maslov, MS
Controls Engineer at Pulsed power Lab
Efremov Institute for Electro-Physical Apparatus
St. Petersburg, Russia
Mobile: +7 (951) 672 22 19
Landline: +7 (812) 461 01 01
