Accelerator/RF systems

Anders SunessonRF group leader

www.europeanspallationsource.seApril 22, 2015

RF Overview

• RF provides the power to accelerate• 2 WPs are covered, WP 8 and WP 17• There are 155 cavities to be powered, each by one

amplifier station• Start at the wall power plug end at the cavity coupler• New development: SML modulator topology• New development: MB-IOT amplifier• Costbook value 166 M€, ≈118 WP8, ≈48 WP 17• A large part of the RF systems is provided in kind

2

RF In Kind discussions

• NC RF systems and Spoke LLRF provided by ESS-Bilbao• Spoke RF transmitters provided by Elettra• Spoke, medium/high beta interlock systems provided by Hungary• 704 MHz LLRF provided by Poland• Phase reference line provided by Warsaw Technical University• Distribution systems spoke, medium and high beta provided by

Huddersfield University• Installation services provided by IFJ PAN Krakow• Ongoing discussions on design of dry HV HF transformers with

Technical University Tallinn, Estonia• Covers all of WP 8 except Master oscillator, medium/high beta

amplifiers• Covers WP 17 except medium/high beta High voltage supplies 3

Master Schedule – RF Systems

Energy (MeV)

Frequency /MHz

No. of Cavities βg Temp / K RF power /kW

Source 0.075 - 0 – ~300 –

LEBT 0.075 - 0 – ~300 –

RFQ 3.6 352.21 1 – ~300 1600

MEBT 3.6 352.21 3 – ~300 20

DTL 90 352.21 5 – ~300 2200

Spoke 220 352.21 26 (2/CM) 0.5 βopt ~2 330Medium

β 570 704.42 36 (4/CM) 0.67 ~2 870

High β 2000 704.42 84 (4/CM) 0.86 ~2 1100

HEBT 2000 – 0 – ~300 –

Spokes Medium β High βDTLMEBTRFQLEBTSource HEBT & Contingency

Target

2.4 m 4.5 m 3.6 m 40 m 54 m 75 m 174 m

75 keV 3.6 MeV 90 MeV 220 MeV 570 MeV 2000 MeV

352.21 MHz 704.42 MHz

RF Technical performances

RF Selected technologies

6

• Two new technology developments are presented• SML – stacked mutli-level modulator topology

• This gives scalable, compact, and cost effective solutions

• Multi-beam IOT• This gives higher efficiency, and a more compact system compared

to klystrons

• The following slides detail technology choices and strategies throughout RF systems

7

Modulators Strategy A

• ESS internal development of a new topology (SML – Stacked Multi-Level)

• Construction and validation of a Reduced Scale prototype rated for 120 kVA (115kV / 20A, 3.5ms / 14Hz) in collaboration with Lund University (LTH). Can power one 704MHz 1.2MWpk klystron

• Project has started in June 2013. Completion and demonstration of technology are foreseen for fall 2015

• Upgrade to the full scale system 660kVA (115kV / 100A, 3.5ms / 14Hz) is a matter of thermal re-design and selection of higher current components. The full scale modulator is able to power 4x 704MHz 1.2MWpk klystrons in parallel. Straightforward approach with low risks

8

Modulators Strategy B

• ESS has launched an Invitation To Tender for the design and construction of one 330kVA modulator• Contract awarded to Ampegon on June 2014• Technical Design Report under review• Delivery foreseen for Feb 2016• Soak testing in Uppsala RF test stand, from March to May(?) 2016

• CEA / Saclay has launched an Invitation To Tender for the design and construction of another 330kVA modulator for their RFQ test stand. It can also serve as a technology demonstrator for ESS• Contract awarded to DTI on Oct 2014• Delivery foreseen for Jan 2016• Soak testing at CEA/Saclay RFQ test stand from January to April(?) 2016

Klystron Modulators for ESS Carlos A. Martins – ESS AB, Accelerator Division, RF Group 9

HFTransformer 1 Lf

Cf

HFTransformer 2 Lf

Cf

HFTransformer 3 Lf

Cf

OIL TANK(NOT PART OF THE

SUPPLY)

KLYSTRON OIL TANK

(NOT PART OF THE SUPPLY)

KLYSTRON BODY

KLYS

TRO

N

HEA

D

HV

CAB

LE

HFTransformer 4 Lf

Cf

HFTransformer 5 Lf

Cf

HFTransformer 6 Lf

Cf

CABINET #2 (INVERTERS)

Rds

Kds

GSw

Rds

Kds

GSw

Rds

Kds

GSw

OFF

ON

DRI

VER

DC/DC #A

LEM

DC-

A

Ldc A

Rcb

Tcb

LEM CB-A

RpCA

AC/DC #ALEM R-A

DA+

DA-

DB+

DB-

DC+

DC-

DRIV

ER

DRIV

ER

DRIV

ER

LEM S-A

LEM T-A

Lf R-A

Lf S-A

Lf T-A

CAP.BANK 1

DRI

VER

DRI

VER

DC/AC #1

LEM

1+LE

M 1-

CAP.BANK 2

DRI

VER

DRI

VER

DC/AC #2

LEM

2+LE

M 2-

CAP.BANK 3

DRI

VER

DRI

VER

DC/AC #3

LEM

3+LE

M 3-

CAP.BANK 4

DRI

VER

DRI

VER

DC/AC #4

LEM

4+LE

M 4-

CAP.BANK 5

DRI

VER

DRI

VER

DC/AC #5

LEM

5+LE

M 5-

CAP.BANK 6

DRI

VER

DRI

VER

DC/AC #6

LEM

6+LE

M 6-

13 1423 24

A1 A224 Vdc

KAC A

13 1423 24

DRI

VER

DC/DC #B

LEM

DC-

B

Ldc B

Rcb

Tcb

LEM CB-B

RpCB

AC/DC #BLEM R-B

DRIV

ER

DRIV

ER

DRIV

ER

LEM S-B

LEM T-B

Lf R-B

Lf S-B

Lf T-B

13 1423 24

A1 A224 Vdc

KAC B

DRI

VER

DC/DC #C

LEM

DC-

C

Ldc CRc

bTc

b

LEM CB-C

RpCC

AC/DC #CLEM R-C

DRIV

ER

DRIV

ER

DRIV

ER

LEM S-C

LEM T-C

Lf R-C

Lf S-C

Lf T-C

13 1423 24

A1 A224 Vdc

KAC C

CABINET #1 (CAPACITOR CHARGERS)

KPreCh23 24

Th PreCh

R PreCh(3x)

MCB

SDE

OF

SD

24 Vdc

No Volt Coil

EMC FILTER

13 1423 24

A1 A224 Vdc

R

S

T

AUX POWER SUPPLY

+ -

(PART OF THE SUPPLY) (PART OF THE SUPPLY)

Jun ’13

From a conceptual design to reality…

Sept ’13 – May ’14

Apr ’14 Aug ’14May ’14

Jan ’15

Experimental results, low voltage stage

Construction and testing of High Voltage Oil tank assembly Feb’15 to Sept’15

The Stacked Multi-Level (SML) modulator: – Development roadmap

9

10

Modulator decision chart (to medium b)

Strategy Ready/Delivery Validated Decision point Outcome

A - SML Fall 2015 End 2015

If A: SML fully validated, Q1 2016

If B: July 2016

Strategy A: Launch call for tender for 660 kVA units medium beta. ESS Bilbao similar action for NC linac

B:1- Ampegon Q1 2016 Mid 2016

Strategy B: Launch call for tender for 330 kVA units for

medium beta. ESS Bilbao similar action for NC linac

Note: higher cost (≈6 M€ Mb), schedule challenges

B:2 - DTI Q1 2016 Mid 2016

11

ESS LLRF prototype and efforts

– mTCA 4 standard– Regulation 352 and function 704 tested– Adaptive feedforward learning– Lorentz force detuning compensation– Tests (352 @ FREIA, 704 @ Saclay)– Klystron linearisation– Requirements on precision

• Control/cavity system modeling• Beam physics (loss) modeling• Regulation system set-up• Handling beam current variations• Handling modulator ripple

• Note all LLRF provided in kind

12

Phase ref line

• First design prepared• Prototyping 2015-2016,

scaled down version to test• Phase reference signal

delivery system• Air pressure system• Temperature control system• Data acquisition, drift

calibration, EPICS interface

• Phase reference line provided in-kind

MO

20dBm, 704.42MHz20dBm,352.21MHz

~50dBm, 704.42MHz~40dBm, 352.21MHz

Temperature controlled within ±0.1°C

… …

704.42MHz, 1 5/8’’ rigid line

Temperature controlled within ±0.1°C

352.21MHz, 1 5/8’’ rigid line

13

High power amplifiers

Section Power /kW Baseline Status

Normal conducting RFQ and DTL 2800 Klystron In kind

Normal conducting bunchers 30 Solid State In kind

Spoke linac 400 Tetrode In kind

Medium beta linac 1500 Klystron Prototyping

High beta linac 1500/1200Klystron/IOT

MB-IOT (decision end 2017)

Prototyping

14

Spoke power sources

• 400 kW tetrode-based solution• Two complete stations to Uppsala University FREIA

facility (Proof of concept)• FAT of tube recently (Thonon)

Results

Peak power

200 kW

Efficiency 66%

Gain 15 dB

Duty 4.6%

15

Medium and high beta (klystron option)

Three klystron prototypes are being procured, from three different manufacturers (Thales, Toshiba and CPI)

ThalesTH 2180

CPIToshibaE37504

Status of the contract Expected delivery date

Thales Contract started in January 2015(Kickoff meeting held at the end of January)Klystron design based on the TH2182 for Cern with minor modificationsDesign review in one month

March 2016

Toshiba Contract started at the beginning of March 2015(Kickoff meeting held on March 17th)Design review next May

May 2016

CPI Contract in place July 2016

Preliminary

drawings

16

Multi-Beam IOT for ESS (High beta baseline)

10 Beam Multi-Beam IOT1.2 MW704 MHz

17

Multi-Beam IOT, courtesy L3, CPI, Thales

00.20.40.60.8

11.21.41.61.8

2

0 2 4 6 8 10 12 14 16

Out

put P

ower

[MW

]

Input Power [kW]

36kV

40kV

45kV

50kV

0

0.2

0.4

0.6

0.8

1

1.2

1.4

0 2 4 6 8 10 12 14 16

Body

Cur

rent

Per

Bea

m [A

]

Input Power [kW]

36kV40kV45kV50kV

0.300.350.400.450.500.550.600.650.700.750.80

0 2 4 6 8 10 12 14 16

Effici

ency

Input Power [kW]

36kV40kV45kV50kV

00.20.40.60.8

11.21.41.61.8

2

0 2 4 6 8 10 12 14 16

Out

put P

ower

[MW

]

Input Power [kW]

36kV

40kV

45kV

50kV

0

0.2

0.4

0.6

0.8

1

1.2

1.4

0 2 4 6 8 10 12 14 16

Body

Cur

rent

Per

Bea

m [A

]

Input Power [kW]

36kV40kV45kV50kV

0.300.350.400.450.500.550.600.650.700.750.80

0 2 4 6 8 10 12 14 16

Effici

ency

Input Power [kW]

36kV40kV45kV50kV

Power and Efficiency Impact of HV

Vk = 48 kVClass-C

Power Transfer Curve

1.2 MW

MAGIC-3D simulation of one beam with MB-IOT off-axis B-field

18

IOTs and power supplies for high beta

• 2 prototypes will be delivered end 2016• Testing at CERN complete mid 2017• IOT/Klystron decision for high beta end 2017

– If IOT looks successful PSU development needed• Proof of concept start 2017• Start of series contract 2018• Delivery first unit 2020

– If Klystron is the choice• Start of series contract 2018• Delivery first unit 2020

19

IOT/Klystron selection criteria

• Technical performance• Project risk• Financial considerations

• Manufacturing capability compatible with timescales• Power output minimum 90% of rated power• Reliability (time to repair/replace, MTBF trip & fault)

• (ESS document ESS-0008307)

20

RF Distribution systems

• Issues: high temperature cooling water in loads – new external development needed

• Several km of waveguides needed

Section Type Status Partner

Normal conducting RFQ and DTL Waveguide In kind ESS Bilbao

Normal conducting bunchers Transmission line In kind ESS Bilbao

Spoke linac Waveguide In kind +Prototype UU Huddersfield University

Medium beta linac Waveguide In kind +Prototype Lund Huddersfield University

High beta linac Waveguide In kind +Prototype Lund Huddersfield University

21

Interlock: Prototype design

– PLC module plus fast module.– PLC monitors slowly varying signals (temperatures etc)– Two FIM (Fast Interlock Module) are being designed in

parallel (arc detectors, pin diodes, etc)• Siemens FM352-5 Fast Boolean Processor (FPGA based) – 12

Inputs / 8 outputs per module. Only 24VDC digital inputs/outputs are available.

• Fast Interlock Module NI cRIO connected via Fieldbus to the main controller PLC CPU. Different signal types I/O are available.

RF Integration and Verification

22

• RF systems will be prototype level tested at CERN (IOT), FREIA (330 kVA modulator, 704 klystron), Lund (Reduced scale SML modulator, 704 klystron)

• In kind contributions will be tested at our partner sites prior to delivery

• RF systems will be installed directly in the gallery and tested on site (by our partners and as part of Polish contribution from Krakow)

• A detailed plan for these activities is needed

RF Organization

• Until EOC there will be– 13 technicians added to WP 8– 5 technicians added to WP 17

23

RF Major Procurements I

• 330 kVA modulator prototype• Awarded t o Ampegon Jan 2014• Cost 1100 k€• Delivery schedule Jan 2016

• 2nd 330 kVA modulator• For Cryomodule test stand Lund• Estimated cost 1440 k€• Call for tender Q4 2015, delivery Q4 2017

• Medium beta linac modulators• 9 x 660 kVA modulators baseline• 10300 k€ total• Possible suppliers Jema, DTI, Ampegon,…• Call for tender Q1 2016, delivery Q4 2017-Q1 2019 24

RF Major Procurements II

• 704 MHz 1.2 MW Multi-beam IOT prototypes• 2 contracts awarded to L3 and CPI/Thales consortium• Cost 5000 k€ together• Delivery scheduled Oct 2016

• 704 MHz 1.5 MW klystron prototypes• 3 contracts awarded to Toshiba, Thales, and CPI• Cost 1400 k€ together• Delivery scheduled March 2016 (Thales), May 2016 (Toshiba), and

July 2016 (CPI)

• Medium beta 704 MHz klystrons• 36 x 1.5 MW klystrons• Cost 11200 k€ total• Possible suppliers Thales, Toshiba, CPI,…• Call for tender Q3 2016, delivery Q2 2018-Q2 2019 25

RF Major Procurements III

• High beta linac modulators• 21 x 660 kVA modulators baseline• 21000 k€ total• Possible suppliers Jema, DTI, Ampegon,…• Call for tender Q4 2017, delivery Q1 2020-Q2 2022

• High beta 704 MHz IOTs• 84 x 1.5 MW IOTs baseline• Cost 26000 k€ total• Possible suppliers Thales, L3, CPI,…• Call for tender Q2 2018, delivery Q3 2019-Q2 2022

26

RF Top risks

27

Issue Risk Solution

A large fraction of the RF systems is designated as in-kind

In kind partners might redesign already designed systems like LLRF, LPS, and Spoke RF transmitters

When milestone slippage is detected, procure from industry

In kind partner personnel not capable of delivering the desired functionality

When milestone slippage is detected, procure from industry

Gallery space is very tight and not all is designed

RF systems might not fit into the gallery

Add space

The klystrons are cooled at high temperature (50 -80 C)

1)Reduced lifetime2)Not stable performance3)Unsafe

Cool klystrons at 30 C

Next Six Months

• HoAs and in kind contracts signatures, and finalisation of the SoWs (mid summer)

• Continued follow-up of IOT, klystron, and modulator contracts

• Finalization of the SML modulator prototype• First HV tests of SML prototype• Hiring of four positions to the RF group• Finalization of interlock system design• Phase reference line prototype

28

RF Summary

• Power to all accelerating cavities provided• Very demanding schedule• Challenging in kind portion• Exciting new developments

• SML modulator topology• MB-IOT concept

29

30

Thank you

• SPARE SLIDES

31

32

HV oil tank assembly(Collaboration between ESS and LTH)- Design of the whole system

undergoing;

HV module (HV transformer + HV rectifier)Construction and validation of one HV module prototype is undergoing:

- HV transformer assembled (first test results obtained two weeks ago);- HV rectifier is under construction (PCB’s delivered last Tuesday)

HV module

control signal

primary voltage

secondary voltage

secondary current

High Voltage oil tank assembly:- Design in view of construction . Collaboration with LU

330 kVA modulator, strategy B1

33

AMPEGON AGH-bridge inverters (x36) based on MOSFET’s (x720)

Electrolythic capacitors(x108)

HVHF transformers (x36 units)

34

330 kVA modulator, strategy B2

Diversified Technologies Incorporated, DTIPulse Transformer (7.4tons; 1’850 liters of oil)

Primary pulse generator (weigth = 5 tons)

35

LLRF system NC

LLRF system:PI-controller

Master Oscillator

Phase Reference Clk 352.21 MHz

KlystronPre-Amp

Load

Cavity

Circulator

KlystronmodulatorPower Grid

4 5

1

3 6 7

9

10

2

8

I

Pz Ctrlfine grain tuning

Motor Ctrlcoarse grain tuning

Pz

M

LLRF system:Motion control

LLRF system:Monitoring & Storing

1 … 10

Warning/Errors

U

36

MO

20dBm, 704.42MHz20dBm,352.21MHz

~50dBm, 704.42MHz~40dBm, 352.21MHz

Temperature controlled within ±0.1°C

• 16dBm at each tap point for LLRF, BPMs, and BSMs• Total 12 taps in prototyping• SNR at each output shall be >70dB in single side bandwidth1MHz• Integral phase noise 1Hz~100kHz shall be >70dB

… …

704.42MHz, 1 5/8’’ rigid line

Temperature controlled within ±0.1°C

352.21MHz, 1 5/8’’ rigid line

Digital Domain

Drift Calibration

AD CAD C AD C AD C AD C AD C AD C AD C AD C

Input from 6 taps and 2 MO outputs

Data Acquisition Board

Data Acquisition and EPICS interface

Input from temperature sensors, air pressures, amplifier protection signals

Data Communication Bus

CPU

7/8’’ Coaxial cable

3/8’’ coaxial cable

Prototype Block Diagram

37

Medium and high beta (klystron option)36 Medium beta elliptical cavities: 704.42 MHz, input power from 207 kW to 866 kW (plus 30% for losses compensation and overhead) saturated power from klystrons up to 1.15 MW

84 High beta elliptical cavities: 704.42 MHz, input power from 835 kW to 1.1 MW (plus 30% with klystrons); 1.2 MW MB IOTs (or klystrons as backup)

Nominal output power 1.5 MW

Frequency 704.42 MHz

BW ≥ +/- 1 MHz

Pulse width 3.5 ms

Repetition rate 14 Hz

Perveance 0.6*10-6

Efficiency >60%

VSWR Up to 1.2

Power Gain ≥ 40 dB

Group Delay ≤ 250 ns

Harmonic Spectral content ≤ -30 dBc

Spurious Spectral content ≤ -60 dBc

Klystron specs

4.5 Cells of 8 klystrons for Medium Beta10.5 Cells of 8 klystrons (IOTs) for High Beta

KlystronsModulators

Racks

38

66

68

70

72

74

76

78

35 40 45 50 55 60

Effici

ency

[%]

Voltage [kV]

Operational OptimisationsCourtesy of L3 Communications

1.3 MW70% eff

00.20.40.60.8

11.21.41.61.8

2

0 2 4 6 8 10 12 14 16

Out

put P

ower

[MW

]

Input Power [kW]

36kV

40kV

45kV

50kV

0

0.2

0.4

0.6

0.8

1

1.2

1.4

0 2 4 6 8 10 12 14 16

Body

Cur

rent

Per

Bea

m [A

]

Input Power [kW]

36kV40kV45kV50kV

0.300.350.400.450.500.550.600.650.700.750.80

0 2 4 6 8 10 12 14 16

Effici

ency

Input Power [kW]

36kV40kV45kV50kV

00.20.40.60.8

11.21.41.61.8

2

0 2 4 6 8 10 12 14 16

Out

put P

ower

[MW

]

Input Power [kW]

36kV

40kV

45kV

50kV

0

0.2

0.4

0.6

0.8

1

1.2

1.4

0 2 4 6 8 10 12 14 16

Body

Cur

rent

Per

Bea

m [A

]

Input Power [kW]

36kV40kV45kV50kV

0.300.350.400.450.500.550.600.650.700.750.80

0 2 4 6 8 10 12 14 16

Effici

ency

Input Power [kW]

36kV40kV45kV50kVIncreased beam voltage provides

for better performance• Increases gain• Increases efficiency• Decreases body current

Simulations are for 10 beams

Plot shows maximum achievable efficiency for various operating points

Power and Efficiency Impact of HV

39

MAGIC Prediction of MB-IOT PerformanceCourtesy of Thales and CPI

Efficiency & Gain vs Output Power

MAGIC-3D simulation of one beam with MB-IOT off-axis B-field • At 1.2 MW, h = 72% with Vk = 48 kV

• At 600 kW• h = 59% with Vk = 48 kV• h = 68% with Vk = 34 kV

Vk = 48 kVClass-C

Power Transfer Curve

1.2 MW Efficiency

Gain

40

Some results from the TH2182 klystron testing at CERN

Nominal output power 1.5 MW

Frequency 704.42 MHz

Beam Voltage 111.4 kV

Beam current 22.2

Repetition rate 2 Hz

Pulse length 1.8 ms

Efficiency 66%

Saturated Gain 45.15 dB

Group Delay 130 ns

The klystron TH2182 has also been tested at ESS parameters

Courtesy of Thales ED and CERN

41

Distribution system layout example MB

ESS needs waveguides inHuge quantity