Examples of ITER CODAC requirements for diagnostics - PowerPoint PPT Presentation

About This Presentation
Title:

Examples of ITER CODAC requirements for diagnostics

Description:

Examples of ITER CODAC requirements for diagnostics S. Arshad Colloquium on ITER-CODAC Plant Control Design Handbook and EU Procurement of Control and Instrumentation ... – PowerPoint PPT presentation

Number of Views:85
Avg rating:3.0/5.0
Slides: 12
Provided by: card105
Category:

less

Transcript and Presenter's Notes

Title: Examples of ITER CODAC requirements for diagnostics


1
Examples of ITER CODAC requirements for
diagnostics
S. Arshad
Colloquium on ITER-CODAC Plant Control Design
Handbook and EU Procurement of Control and
Instrumentation for ITER 28 October 2008
2
Hot fusion plasma can be contained in a magnetic
field
3
Containment improves with size ITER will be
much larger than todays machines
R (m) 6.2
a (m) 2
IP (MA) 16
Bt (T) 5.3
Paux (MW) 40 90
Pa (MW) 80
Q (Pfus/Pin) 10
Prad (MW) 48
tpulse (s) 400
New engineering and physics challenges for
measurement and control
4
Wide range of diagnostics needed to diagnose
fusion plasma
Port type
No. used
Equatorial
9
Upper
12
Lower
9
Additionally many measurements inside vessel
  • UPPER PORT 10
  • X-Ray Survey
  • Imaging VUV Spectroscopy
  • UPPER PORT 11
  • Edge Thomson
  • EQUATORIAL PORT 11
  • X-Ray Crystal Spectroscopy, array
  • Divertor VUV Spectroscopy
  • X-Ray Survey
  • Core VUV Monitor
  • Neutral Particle Analyser
  • Reflectometry
  • EQUATORIAL PORT 9
  • MSE
  • Toroidal Interferometer / Polarimeter
  • ECE
  • Wide Angle TV/IR
  • DIVERTOR PORT 10
  • X-point LIDAR
  • Divertor Thomson Scattering
  • H-Alpha Spectroscopy
  • DIVERTOR PORT 8
  • Divertor Reflectometry

5
The EU will supply a range of diagnostics to ITER
General scheme for processing of diagnostic data
Ports for diagnostics heating systems
Physics studies
Analog processing
Off-line processing
ADC
Real-time processing
Controller
Machine protection plasma control
Processed data from diagnostics (Courtesy of
EFDA-JET)
About 40 diagnostic systems installed in ports
and inside / outside the toroidal chamber 13 to
be supplied by the EU
Plasma shape neutron profile
Plasma wall interaction
Temperature density profiles
  • Wide-angle viewing system
  • Magnetics
  • Radial neutron camera
  • Core Thomson scattering
  • Bolometers
  • Core charge exchange recombination spectrometer
  • Hard X-ray monitor
  • Plasma position reflectometer
  • Pressure gauges
  • Thermocouples
  • LFS collective Thomson scattering
  • High-resolution neutron spectrometer
  • Gamma-ray spectrometers

6
The magnetics diagnostic is a large system for
basic plasma control, machine protection and
physics studies
Purpose
Prototype magnetics sensors
Control
Protection
Physics
  • Determine plasma current, shape and movement
  • Measure thermal energy of plasma
  • Detect and quantify plasma instabilities
  • Reconstruct magnetic flux surfaces (equilibrium)
  • Detect and quantify any current flowing from
    plasma into vessel

?
?
?
?
?
?
?
?
?
In-vessel pick-up coil
?
?
Ex-vessel pick-up coil
In-vessel pick-up coil
  • Diagnostic comprises pick-up coils, flux loops,
    Rogowski coils
  • 1050 sensors inside the vessel (shown in figure)
  • 600 additional sensors outside vessel

Hall probe
External rogowski coil
7
Overview of magnetics signal processing
Event triggers
B
Off-line processing
dB/dt
Int
Physics studies
ADC
Real-time processing
Amp
Control protection
dB/dt
  • Around 1650 sensors in total
  • Slow (4kHz) ADCs for basic equilibrium
  • Fast (1 MHz) ADCs for instabilities
  • Typically with optical isolation
  • Data stored for specialist off-line studies
  • Real-time signals distributed to other plant
    systems (power amplifiers for tokamak magnets,
    machine protection systems)
  • Digital or analogue integrators
  • Amplifiers

ALL NUMBERS ARE INDICATIVE
8
Plasma current and shape (1/2)
  • Plasma current measured by integrating magnetic
    field over poloidal contour (Amperes law)
  • Plasma shape characterised by gap between plasma
    boundary (solid red line) and first wall
  • Shape controlled by changing current in tokamak
    coils

9
Plasma current and shape
Similar arrangement for 410 in-vessel Rogowski
coils feeding vessel current reconstruction code
Event triggers
B
Off-line processing
dB/dt
Int
Physics studies
ADC
Real-time processing
Amp
Control protection
dB/dt
  • Around 750 sensors (of which 380 in-vessel)
  • Typical raw signal from 0.05m2 pick-up coil in
    /-60mV range under normal operation /-5V at
    disruptions
  • Integrated signals typically sampled at 4kHz
    (20kHz at events)
  • Typically 16 bit ADC with dithering, 25 bits
    without)
  • Calibration of signals
  • On-line data validation checks and corrective
    actions (e.g. voting system with 3 toroidal
    positions)
  • Second plasma current calculation from individual
    signals
  • Plasma boundary and plasma-wall gaps determined
    (1-2cm accuracy) 100k FLOP/cycle (10ms cycle time
    ? 0.01GFLOPS)
  • Control signals generated for gap control and
    distributed to power amplifiers for tokamak coils
  • Data stored for specialist off-line studies
    including full equilibrium reconstruction
    combining data from other diagnostics (20GB per
    pulse)
  • Individual signals integrated (typical time
    constant 100ms output /-5V) and digitised
    separately
  • Integrated signal in range of 0.06Vs frequency
    response 10kHz drift lt0.35mVs after pulse of
    3600s
  • Summing integrator for hardware calculation of
    plasma current (10kA-15MA range, 1 accuracy)

ALL NUMBERS ARE INDICATIVE
10
High frequency instabilities analysis control
Event triggers
B
Off-line processing
dB/dt
Int
Physics studies
ADC
Real-time processing
Amp
Control protection
dB/dt
  • Around 270 high frequency sensors (with response
    up to 100kHz)
  • 16 bit resolution likely to be adequate
  • Sampling rates up to 1 MHz
  • Event triggering to manage data quantities
  • Data stored for specialist off-line studies of
    order 50GB per pulse
  • Real-time signals for feedback control
    (resistive-wall modes)
  • Additional, more specialised, event triggers
  • High frequency results in relatively strong
    (voltage-range) signals which can be recorded
    directly with low gain
  • Frequency response up to 300kHz
  • RMS signals from summing amplifiers may for rapid
    overview of instabilities or for event triggering

Similar arrangement for around 380 in-vessel
sensors for plasma vertical speed control 10kHz
sampling 30GB storage 1GFLOPS
ALL NUMBERS ARE INDICATIVE
11
Overview of requirements for some diagnostics
System
Electronics
ADCs
Storage (per pulse)
Magnetics
  • 1200 integrators
  • 650 amplifiers
  • 1600 slow ADC channels (20kHz)
  • 270 fast ADC channels (1 MHz)

110GB
Bolometry
  • 500 lock-in amplifiers (50kHz)
  • 500 ADC channels

360MB
Charge Exchange
  • Read-out from up to 75 CCD cameras (100
    spectra/sec. 560 pixels each)
  • N/A

30GB
Core LIDAR TS
  • 150 ADC channels at 20GSa/S 10-bit samples

100MB
ALL NUMBERS ARE INDICATIVE
Write a Comment
User Comments (0)
About PowerShow.com