1. HLRF Post-TTC Meeting (Fukuda)
Recent Status of DRFS
S. Fukuda (KEK)
Scheme of SB2009
Comparison between Diode Klystron (+ Marx)　and MA Klystron (+DC P/S & MA Modulator)
Costing in DRFS
Summary
HLRF
HLRF Post-TTC Meeting (Fukuda)

2. HLRF Post-TTC Meeting (Fukuda)
Scheme of SB2009
HLRF
HLRF Post-TTC Meeting (Fukuda)

3. ILC Main Linac TD Parameters:
Number of cavities
14,560
Repetition rate
5 Hz
Gradient
<31.5> MV/m (25 to 38 max. range)
2 K Cryogenic load
1.3 W / cavity average
Final Energy Stability / energy spread
0.1% (~1% per RF unit)
250 GeV/beam
# of bunches
bunch spacing
beam current
beam duration
rf peak power
fill time, ti
rf pulse duration
full beam RDR
2625
369.2 ns
9 mA
0.969 ms
294.2 kW
0.595 ms
1.564 ms
DRFS
1313
738.5 ns
4.5 mA
147.1 kW
1.190 ms
2.159 ms (up 38%)
KCS
535.1 ns
6.21 mA
0.702 ms
203.0 kW
0.862 ms
RDR – HLRF (backup)
553.8 ns
6 mA
0.727 ms
196.1 kW
0.893 ms
1.619 ms (up 3.5%)
PAC Prague,
Marc Ross - Fermilab

4. Upgrade Pass from SB2009 and DRFS
HLRF
HLRF Post-TTC Meeting (Fukuda)

5. Current Scheme of DRFS (Fukuda) LCWS11
3 operation mode (Low Energy 10Hz, SB2009 and Full scheme) and DRFS Layout
(1) Low energy 10Hz operation: 250GeV, 4.5mA, 10Hz
All units have a capability of 2.3ms pulse width, 10Hz.
Facility requires 144% power capability.
Numbers of active klystrons are 50% to 70% depending on the sorted kly. group.
(2) Reduced bunch operation: 500GeV, 4.5mA, 5Hz
All units have a
capability of 2.3ms
pulse width, 5Hz.
Facility requires 144%
power capability.
Numbers of active
klystrons are same in
sorted kly. group.
Same units
(3) Full energy operation: 500GeV, 9mA, 5Hz
Increase units
Old units have same
capability, and new
units with 1.8ms pulse
width.
Facility for new units
requires 113%
power capability.
2011/9/28
Current Scheme of DRFS (Fukuda) LCWS11

6. HLRF Post-TTC Meeting (Fukuda)
3 operation mode (Low Energy 10Hz, SB2009 and Full scheme) and DRFS Layout（２）
All units have a capability of 1.6 ms pulse width, 10Hz.
Numbers of active klystrons are 35 %.
All units have a
capability of 1.6 ms
pulse width, 5Hz.
Numbers of active
klystrons are 2/3 of Full case and P/S also 2/3.
Old units have same
capability, and new
units (1/3) with 1.6ms pulse width.
Need upgrade period
HLRF
HLRF Post-TTC Meeting (Fukuda)

7. HLRF Post-TTC Meeting (Fukuda)
Comparison between Diode Klystron (+ Marx) and MA Klystron (+DC P/S & MA Modulator)
HLRF
HLRF Post-TTC Meeting (Fukuda)

8. HLRF Post-TTC Meeting (Fukuda)
Technical Concern of DRFS and Cost comparison with different scheme (1)
DRFS was based on the Modulated-anode(MA) type klystron and associated power supply　-　DC power supply and MA modulator.
Simple configuration and cost benefit
There are concerns about some technology-R&D of some key points takes longer time and afraid not in time of TDR preparation
Reliable Crowbar Circuit
---- Gap switch reliability though cheap, not high reliability
-----How about other device such as thyratron and ignitron?
thyratron technology degrading and relatively short life.
ignitron-so far stable from the Tristan and KEKB experience and we are considering to use it.
-----Solid state switch is reliable but expensive
Requirement of cheap and compact pulse sag compensation circuit
-----bouncer circuit is reliable and successive, but need space and not easy to change the specification for longer pulse width
-----Marx circuit type sag compensator is considered
HLRF
HLRF Post-TTC Meeting (Fukuda)

9. HLRF Post-TTC Meeting (Fukuda)
Technical Concern of DRFS and Cost comparison with different scheme (2)
If crowbar circuit using solid-state switch is employed, introduction of Marx modulator plus diode-type klystron has a simple solution.
Start to compare the cost of two schemes
Concerning to the Marx modulator, there are several versions by several companies, and examples to be used in the accelerator facility.
Technically both scheme reliabilities ( MA-type klystron and diode-type klystron) in final version will be same degree
How about the cost difference?
HLRF
HLRF Post-TTC Meeting (Fukuda)

10. HLRF Post-TTC Meeting (Fukuda)
PS System for DRFS
M. Akemoto, KEK
PS System for Modulation-anode-type klystrons
PS System for Diode-type klystrons
HLRF
HLRF Post-TTC Meeting (Fukuda)

11. HLRF Post-TTC Meeting (Fukuda)
PS system for Modulation-anode-type klystrons 6 2 3
Crowbar Circuit
(0V)
Droop compensation PS
6.6 kVAC, 3φ
VCB
Transformer
Input:6.6kV
Output:
420V,
200V,
100V
Klystron #1
Klystron #13
Switching PS
MA modulator MA
Spark Gap Switch
Anode
Pulser 1 10 HK
HV cable
Heater PS H 4 5
Klystron
Heater/Cathode
HV Box #1 9 7 8
Control 11
6.6kV Main Power Line
HLRF
HLRF Post-TTC Meeting (Fukuda)

12. HLRF Post-TTC Meeting (Fukuda)
Crowbar and Bouncer
Marx Bouncer
output G Ci
2Ci
20Ci
Ignitron
HLRF
HLRF Post-TTC Meeting (Fukuda)

13. HLRF Post-TTC Meeting (Fukuda)
Cost Estimation List
No.
Component
Quantity
Suppliers
Specification 1
VCB
Toshiba, Mitsubishi
6.6 kV , 3 phase, 100 A fault current 2
Transformer
Nichicon
6.6 kV, 3φ / 420 V,3φ, 200 V, 1φ, 100 V,1φ 300 kVA 3
DC Switching PS
Matsusada, Nichicon
-65.8 kV, 166 kW 4
Capacitor bank
44 µF,-65.8 kV 5
Crowbar circuit
Ignitron or gap switch 6
Droop compensation PS
PPJ, Nichicon, Matsusada, DTI
-13 kV, 263 A peak, 2,4 ms 7
Heater PS
NTD
200 V AC, 3 kVA, 80 kV Isolation Trans. 8
MA modulator
Nissin,Nichicon
-53 kV, 2.4 ms, 5 Hz 9
Klystron Heater/Cathode HV Box 13
KEK, NTD
HV floating 10
HV Cable -
Fujikura
RG-220/U , 150 kVAC 11
Control
PLC, optical link
HLRF
HLRF Post-TTC Meeting (Fukuda)

14. HLRF Post-TTC Meeting (Fukuda)
PS system for Diode-type klystrons 2 3
(0V)
6.6 kVAC, 3φ
VCB
Transformer
Input:6.6kV
Output:
420V,
200V,
100V
Klystron #1
Klystron #13
Marx
Modulator
Heater Trans.
Oil Tank 7 1 HK
HV cable
Heater PS H
Klystron
Heater/Cathode
HV Box #1 6 4 5
Control 8
6.6kV Main Power Line
HLRF
HLRF Post-TTC Meeting (Fukuda)
Klystron system connected to HV cables in parallel

15. HLRF Post-TTC Meeting (Fukuda)
Cost Estimation List
No.
Component
Quantity
Suppliers
Specification 1
VCB
Toshiba, Mitsubishi
6.6 kV , 3φ, 100 A fault current 2
Transformer
Nichicon
6.6 kV, 3φ / 420 V,3φ, 200 V, 1φ, 100 V,1φ,
300 kVA 3
Marx Modulator
DTI, SLAC, PPJ
67.5kV, 273 A, 2.4 ms, 5 Hz 4
Heater PS
Matsusada,Takasago
134V, 18.3 A, 3 kVA, Constant current 5
Heater Trans. Oil Tank
NTD
200 V AC, 3 kVA, 80 kV Isolation Trans. 6
Klystron Heater/Cathode HV Box 13
KEK, NTD
HV floating 7
HV Cable -
Fujikura
RG-220/U , 150 kVAC 8
Control
PLC, optical link
HLRF
HLRF Post-TTC Meeting (Fukuda)

16. Marx Modulator Specification
Performance requirements
67.4 kV peak voltage
273 A peak current
2.4 ms pulse width
5 Hz pulse repetition frequency
+/- 0.5% flat top
221 kW average power
<20 J deposited into klystron from gun spark
Input voltage 3φ, 420 VAC, 50 Hz
HLRF
HLRF Post-TTC Meeting (Fukuda)

17. HLRF Post-TTC Meeting (Fukuda)
Summary about P/S
We have designed two kind of PS Systems for DRFS.
Now, we ask some companies to estimate the cost, size of the system components.
We will compare them and decide the PS system for DRFS.
HLRF
HLRF Post-TTC Meeting (Fukuda)

18. HLRF Post-TTC Meeting (Fukuda)
Costing in DRFS
HLRF
HLRF Post-TTC Meeting (Fukuda)

19. New DRFS Plan in Kamaboko
If DRFS design is changed from MA-klystron system to Diode-klystron system, configuration is almost the same as before. Footprint of new scheme is now under design.
Diode Klystron
Or MA Klystron
Marx Modulator
Or DC P/S + MA Modulator
HLRF
HLRF Post-TTC Meeting (Fukuda)

20. Cost Difference among the two DRFS
Discussion about the cost only in Kamaboko Tunnel
Klystrons
Including recent specification change Body design (RF circuit design) and beam optics design are the same among the DRFS diode and DRFS MA klystrons
Body design (RF circuit design) and beam optics design are the same among the DRFS diode and DRFS MA klystrons
Gun design and focusing (permanent) magnet design of diode type is simpler for diode type klystron
For 8000 manufacturing, Toshiba says both cost is not so different in the first order approximation
Other factors such as the manufacturing method and automatic process of fabrication, measurement and processing give the larger cost effects
From that view point, processing of klystron in ILC site is very important factor (which should be discussed later)
Modulator
In original plan of MA-klystron DRFS, simple DC power supply and MA modulator are considered, but thereafter additional specification such as the back-up system, the switching regulator, the crowbar, and the bouncer requires the complexity of cost and system structure.
Diode-type klystron and modulator system solves some aspects of above points.
Cost estimation is asked to SLAC and DTI now, and we will quote to other possible companies. DTI proposed Marx modulator and solid state hard switch modulator, and both cost estimation will be performed in a month. Specification and description will be performed by Akemoto.
If ambiguity come from the absence of reliable technology described before in MA-type DRFS is considered, cost of diode type DRFS is expected to be cheaper.
Power Distribution System
Recent PDS change in DRFS is to introduce circulators and variable hybrids.
These changes result in cost increase.
PDS cost estimation, there are now changes between two DRFS schemes.
Cost estimation is based on the RDR basis.
HLRF
HLRF Post-TTC Meeting (Fukuda)

21. Cost Difference among the DRFS and RDR
Discussion about the cost only in Kamaboko Tunnel
General
Including recent specification change described before, re-estimation is required and this results more most than the estimation of SB2009.
Klystrons
Basically DRFS klystron cost is more expensive since one RDR system contains 13 (12) klystrons and unit price of DRFS klystron is higher than the 1/13 times price of 10 MW MBK.
Target price of DRFS we pursue is to make smaller the difference among the DRFS klystron and MBK.
Basic condition of manufacturing such as in-site auto-processing of klystron will help this approach.
In 10 MW MBK, also in-site auto processing is helps the cost decrease but process is more complicated than DRFS and cost reduction effect will be smaller than DRFS case.
In diode-type DRFS, klystron socket is simple and oil-free system (is expected) and it has the benefit.
Modulator
If both types employ the Marx modulators, almost the cost will be same in the first order though the out put voltage is different ( 70 kV in DRF and 110 kV in RDR)
In the case of Kamaboko tunnel, DRFS does not need the back-up system therefore significantly the cost is the same order.
We are interesting about the solid state hard SW modulator and its price.
Cost estimation of main modulator are estimated by the company base ( and SLAC base)
KEK have a plan to introduce the cheaper modulator in STF-II and now we are preparing to have an international bit.
Power Distribution System
Recent PDS change in DRFS result in small difference or almost equal cost effect between the DRFS and RDR.
Cost difference is essentially come from the difference of klystrons. Other factors on DRFS is depend on the availability, operability and reliability.
HLRF
HLRF Post-TTC Meeting (Fukuda)

22. Common Understanding to Estimate the Cost of HLRF
In order to perform the cost estimation in various models in HLRF, comon understanding about the specification is important.
Cavity strings scheme in cryomodule, 989 or 888?: Common understanding is necessary, and I think 888 system should be employed.
Understanding of total overhead numbers of RF source in ML, electron source, positron source and DTML.
Overhead of klystron power considering LLRF feedback margin.: Common understanding including LLRF people to stand on the common basis of cost estimation. This will be related to the output power of klystron.
Is sorting necessary? If DRFS introduce circulator, this will be the same as KCS and discuss the common basis.
Concerning about RDR
RDR, an RDR based on single tunnel with diameter of 5.5m (4.5m) and an RDR based on Kamaboko tunnel, should be prepared, but conclusion will be discussed. Who is responsible for RDR is also the issue.
Is single tunnel with 5.7m diameter DESY type specification?
Is RDR system replaced after RFS in Kamaboko tunnel?
HLRF
HLRF Post-TTC Meeting (Fukuda)

23. Understanding of In-site Facility for Klystron Processing
In DRFS, Cost estimation of DRFS klystron are based on the basic condition of on-site processing.
In ILC host laboratory, several fractions of modulators are installed in advance and klystron processing will be performed automatically, and this helps lot for cost reduction in DRFS klystrons.
Extra cost investing is unnecessary in both the company and ILC in this method.
Single ILC host laboratory? A few hub-Lab?
This will be also linked to the numbers of company to order. Cost for testing person etc, will be the point of discussion.
In RDR, auto processing described above is not easy comparing with DRFS klystrons, but employing similar system is also expected to be cheaper cost estimation. And this will be also understood commonly.
HLRF
HLRF Post-TTC Meeting (Fukuda)

24. HLRF Post-TTC Meeting (Fukuda)
Summary
DRFS introduces 6mA scheme, therefore SB2009 and low energy 10 Hz option, presented schemes are on the same bases.
DRFS compares the cost between the diode-type klystron scheme (+ Marx modulator) and the MA klystron scheme (+DC P/S & MA modulator)
Several remarks of costing in DRFS are presented.
HLRF
HLRF Post-TTC Meeting (Fukuda)