The ITER Neutral Beam
injectors
Antonio Masiello
A.Masiello – Colloquium on the ITER-CODAC “Plant Control Design Handbook” - 27-28 October, Barcelona
1
Neutral Beam injection: principles
Accelerator
Ion
Neutraliser
source
Residual ion
Dump (RID)
Plasma
D beam
A.Masiello – Colloquium on the ITER-CODAC “Plant Control Design Handbook” - 27-28 October, Barcelona
2
The configuration of the NB
injectors in ITER
A.Masiello – Colloquium on the ITER-CODAC “Plant Control Design Handbook” - 27-28 October, Barcelona
3
The Neutral Beam injector
Bushing
Beam Source
Vessel rear door
Passive
Magnetic Shield
Top Active coils
Beam Line Vessel
top lid
Fast shutter
HNB
source
Absolute valve
Beam Source
Vessel
VVPSS box
Drift Duct
Neutralizer
RID
Cryopump
Calorimeter
Bottom
Active coils
Beam Line Vessel
A.Masiello – Colloquium on the ITER-CODAC “Plant Control Design Handbook” - 27-28 October, Barcelona
4
NB Power balance and main
specifications
POWER
SUPPLY
5559
BEAM
SOURCE
INPUT
POWER
5
5
0.2
40
The NB 48
injector
to PLASMA
1718
ACCELERATOR
DUCT
RID
Beam energy
Ion species
Accelerated ion current at the grounded grid
Average accelerated ion current density at the grounded grid
Current density uniformity over the extraction area
0.6
CALORIMETER
NEUTRALISER
Power delivered to the plasma per injector
Pulse length
1720
1620
0.05
24
25
1
TRANSMISSION
LINE
ION SOURCE
OTHER
POWER
COMPONENTS SUPPLY
BEAM LINE
16.5 MW
1 MeV
D40 A
200 A/m2
 10 %
≤ 3,600 s
A.Masiello – Colloquium on the ITER-CODAC “Plant Control Design Handbook” - 27-28 October, Barcelona
5
The ion source
Cooling
manifolds
Coaxial RF
conductors
Cs ovens
Capacitors
Source
case
Drivers
Rear view of the RF ion source
Half size ion source test facility
Courtesy of IPP-Garching
A.Masiello – Colloquium on the ITER-CODAC “Plant Control Design Handbook” - 27-28 October, Barcelona
6
The MAMuG accelerator
1MV accelerator
5 stages of 200kV
1 segment
BEG
δBEG=0.15 mm
1280 apertures
4 segments x 4 groups,
5x16 apertures in a group
AEG
δAEG=0.6 mm
0 mm“Plant Control
A.Masiello – Colloquium on the ITER-CODAC
Handbook” - 27-28
October, Barcelona
0.43 mm
(out ofDesign
plane deformation)
7
The beam line components
Component
Max heat load [MW]
Max PD [MW/m2]
The
Max water flow [Kg/s]
Neutraliser
4.56
2.1
Beam
30 Line
Rid
Calorimeter
20
22
6
22
Components
90
198
Neutraliser
RID
A.Masiello – Colloquium on the ITER-CODAC “Plant Control Design Handbook” - 27-28 October, Barcelona
Calorimeter
8
The NB high vacuum pumping
1 section
Cryopanel: 4.6K
supercritical He
Shielding: 80K
gaseous He
1 module with 4
sections in
parallel
Neutraliser
A.Masiello – Colloquium on the ITER-CODAC “Plant Control Design Handbook” - 27-28 October, Barcelona
9
The Power supplies
A.Masiello – Colloquium on the ITER-CODAC “Plant Control Design Handbook” - 27-28 October, Barcelona
10
The Power supplies
A.Masiello – Colloquium on the ITER-CODAC “Plant Control Design Handbook” - 27-28 October, Barcelona
11
Neutral Beam Test Facility
at Padua - Italy
The main risk
mitigation measure
for resolving NB
issues
The NBTF lay-out
reproduces the one
of the ITER NB-1
A full size source
to start in 2012
A full neutral beam
line to start in 2014
A.Masiello – Colloquium on the ITER-CODAC “Plant Control Design Handbook” - 27-28 October, Barcelona
12
Global operating states
Construction and Long Term Maintenance (LTM)
Short Term Maintenance (STM)
Test and Conditioning Operation (TCS)
 Cryopump regeneration at 400 K
 Cryopump cool-down
 Cryopump warm-up to ambient temperature
 HV conditioning over extraction and acceleration grids
 ion source plasma without extraction
 ion beam accelerated
 ion beam neutralized
 residual ion dump active
Short Term Stand-by (STS)
 Cryopump regeneration at 100 K
Pulse Operation State (POS)
 Beam on calorimeter
 Beam on target without plasma
 Beam on target with plasma: beam normal operation of in ITER pulse.
Beam is interlocked (e.g. tokamak plasma density)
A.Masiello – Colloquium on the ITER-CODAC “Plant Control Design Handbook” - 27-28 October, Barcelona
13
Control system main parameters
The NB Injector Control System will control the following main parameters:












Power to the RF driver
Plasma grid current
Bias Voltage
Extraction grid voltage
Acceleration grids voltages
Residual Ion dump biasing
Caesium oven temperature
Gas flows
Fast shutter control (and absolute valve)
Beam on/off-axis injection
Magnetic compensation coil current
…
A.Masiello – Colloquium on the ITER-CODAC “Plant Control Design Handbook” - 27-28 October, Barcelona
14
Control system preliminary
architecture (NBTF)
CSS Central Safety System CIS Central Interlock System
PSS Plant Safety system
PIS Plant Interlock System
Courtesy of the
RFX Association
A.Masiello – Colloquium on the ITER-CODAC “Plant Control Design Handbook” - 27-28 October, Barcelona
15
Main acquisition requirements
The data acquisition system of each NB Injector will include the instrumentation
needed to condition, record, display and analyze the measured signal coming from
the beam line
•
•
•
•
Standard analog inputs to CODAC
Standard digital inputs to CODAC
Standard digital outputs from CODAC
Timing outputs from CODAC








Temperature measurements
Status signals
Gas pressure meas.
Residual pressure meas.
B field (static) meas.
Position transducers
Water and gas flow meas.
……
some thousands
about 100
about 100
few
 Most of the signals sampling speed is 10100Hz
 For higher speeds up to MHz, a baseline
speed of KHz is foreseen and an event
driven acquisition with a window of few ms
to acquire the signal up to some MHz
 Fastest interlock 100ms
A.Masiello – Colloquium on the ITER-CODAC “Plant Control Design Handbook” - 27-28 October, Barcelona
16
References
 ITER neutral beam heating and current drive system 2001 Design
Description Document N53 DDD
 V. A., Final reports, EFDA contract: TW6-THHN-NBD1
 A. Luchetta et al., Final report - Preliminary specification of the architecture
of the control, interlock and safety systems for the NB test facility - EFDA
contract: TW6-THHN-NBTF1
 Plant control design handbook
https://user.iter.org/?uid=27LH2V&version=v3.0
 Systems Requirement Document (SRD) NBH and CD PBS 53
 L. Svensson, private communication
A.Masiello – Colloquium on the ITER-CODAC “Plant Control Design Handbook” - 27-28 October, Barcelona
17