Areal RF Stationcandle.am/.../uploads/2015/05/TAC-2013-ArealRFStation.pdfAcharyan 31, 0040, Yerevan, Armenia Tel / FAX (+374-10) - 629806 RF System 2 The AREAL RF system will consist

Areal RF Station

Yerevan 16.07.2013

A. Vardanyan, L. Hakobyan, H. Avdishyan, H. Davtyan, H. Poladyan

Acharyan 31, 0040, Yerevan, Armenia Tel / FAX (+374-10) - 629806

RF System

2

The AREAL RF system will consist of 3 RF stations:

Each RF station has 1 klystron, HV modulator, a low-level RF system, preamplifier and an interlock and control system.

1 station is required for RF Gun

2 (or 1 station) stations – for accelerating section(s) operation

LLRF systems which control the amplitude and the phase of the RF

RF power 7 MW in peak at 3 GHz

Interlock and control system


The Required Operation Parameters

• Peak power 6 MW

• Gradient 17 MV/m

• RF pulse duration 3.8 µs

• Repetition rate 1-2 Hz

3


RF Power Source

• Frequency 3 GHz

• RF Pulse Duration 3.8 µs

• Repetition Rate 1-2 Hz

• Cathode Voltage 190 - 200 kV

• Beam Current 95 - 105A

• HV Pulse Duration 3.8 µs

• RF Peak Power 7 MW

4


K211 Klystron Parameters

• Output Power peak 7 MW

• Efficiency 40 %

• Gain (min. dB) 31

• Beam voltage 200 KV

• Beam peak current 92A

5


KY211 Klystron Main Parameters

• Water and Air Cooling For Operate Rate (50Hz)

• Water flow to body 3.64 l/min min

• Water flow to collector 20.5 l/min min

• Resistance of cooling water 50 kOhm cm min

• Air flow to output window 85 l/min min

• Cooling Air pressure 2.1 kg/cm2 min

6


KY211 Klystron Main Parameters

7

5

5.1

5.2

5.3

5.4

5.5

5.6

5.7

5.8

5.9

6

6.1

6.2

6.3

6.4

6.5

6.6

6.7

6.8

6.9

7

7.1

0 1 2 3 4 5 6

30

31

32

33

34

35

36

37

38

39

0 1 2 3 4 5 6

Peak RF Input Power in kW

Pe

ak

RF

Ou

tpu

t P

ow

er

in M

WG

ain

in

dB


Low Level Radio Frequency Control

Characteristics of Signal/Probes:

• Phase stability 0.1 deg@3GHz

• Amplitude stability 0.1%

• Amplitude dynamic range 40 dB

• Ready to be integrated into the EPICS control system

8

The LLRF system ordered by I-Tech LIBERA.

1st stage.


RF Control System

Requirements for the RF control system

• Phase and amplitude stability of the accelerating field during 2 µs flat-top RF pulse – Field amplitude control 0.1%– Phase control 0.1°

• A frequency and phase stable master oscillator for RF reference signals to measure the cavity fields

The RF control system will provide:

– Remote control for all RF components– An opportunity to change the necessary parameters such as

waveguide tuners, phase shifters, etc.

9


LLRF / Control

RF Amplifier

Master OscillatorTi

min

g

Modulator

GunInterlock

Cooling

GunCavityWaveguide System

Phase shifter,Couplers,

Loads,Circulators, etc.

RF Gate

Vacuum

Pickups & Probes

Klystron

ACC1

LaserOpticsLaser

Cathode

?

Control System Block Scheme Overview

10


Master Oscillator

The Master oscillator designed by InWave AG according

to our requirements. • Frequency ports:

– 1x 1Hz 1x 9MHz

– 1x 2Hz 1x 81MHz

– 1x 9MHz 1x 250MHz

– 1x 81MHz2x 90MHz

– 1x 125MHz 2x 10MHz (Secondary)

– 1x 250MHz 1x 10MHz (main)

– 2x 500MHz

– 1x 1GHz

– 2x 3GHz

11


The Measurement Results

The picture describes RMS phase Jitter 6.47 fsec !

12


The Location of RF Equipment

13


RF Test stand

• Modulator (HV pulse power source)

• HV pulse modulator

• 1:18,2 pulse transformer in an oil tank.

• The nominal pulse duration is 3.8 µs.

• Requirements to the flat top ripple

– should not exceed ±1%.

– The pulse-to-pulse stability better than ±0.5%.

14


Amplitude flatness ~ 1.2%

RF Station

K211 Modulator

Measurements

15


Measurements

16

K211 Modulator

> 200 kV


Equipment

LB480A Pulse Profiling USB PowerSensor

Specifications

50 MHz to 8 GHz (functional to 10 GHz) - 60 dBm to +20 dBm1.95% Total Error

17


Equipment

18

Power Meter GUI

Pulse profiling GUI

Power Meter Measurements 10 MHz Pulse Profiling (standard) 100 kHz Time resolution 0.1 us10 % to 90% Rise Time ~100 ns (-70 to -20 dBm pulse measured @ 4 GHz)

10 % to 90% Fall Time ~100ns (-70 to -20 dBm pulse measured @ 4 GHz)


Equipment

19

0

1

2

3

4

5

6

7

8

9

0 2 4 6 8 10 12

Power Amplifier output (+24dB Att.)


Klystron V-A Characteristics

20

A [A] V [kV]

33.(3) 81.9

36 92.82

52.2(6) 131.04

66 163.8

69.(3) 174.7

77.(3) 192.9

90.(6) 209.3

0

10

20

30

40

50

60

70

80

90

100

0 50 100 150 200 250

I [A

]

U [kV]

21.11.2012

Typical

23.10.2012


S-parameters

21

Directional coupler 1 Directional coupler 2

S11 -17,78 dB S11 -19,316 dB

S12 -0,615 dB S12 -0,613 dB

(FW) S14 -76,8 dB (FW)S14 -76 dB

(REF) S23 -76,8 dB (REF)S23 -73,2 dB

Directional coupler 1

Directional coupler 2


TH2436 Modulator V-A Measurements

22


After adjusting modulator coils we get +/- 1%

TH2436 Modulator V-A Measurements

23


Net Stability Measurements

24

Network±2.4V/330V0.7%


Measurements

25

PS12V out±380mV/12V1.5%


Solenoid and Body Thermocouple Calibration

0

200

400

600

800

1000

1200

1400

1600

1800

0 10 20 30 40 50

R[*

2kO

m]

T[°C]

Date of measurement 22.10.2012


Klystrons Input Resonant Frequency Measurement

YK1110K211

t=28oC

27

Resonant TM010 mode

On axis

Ez [MV

/m]

z [cm]

Cavity parameters for TM 010 resonant mode

Frequency – f [GHz] 2.99646

Unloaded quality factor – Q0 15292.34

Shunt impedance – Rsh=V 2/(2 Pd) [MΩ] 2.1174765

Rsh /Q0 [Ω] 138.4665

External quality facor – Qe 15434.52

Loaded quality factor – Q=(1/Q0+1/Qe)-1 7681.55

Coupling factor – β=Q0/Qe 0.99

Natural filling time (loaded/unloaded) –

τ=2 Q/(2π f) [μs]

0.816

π – mode freq. – 2.99646 GHz

A. Tsakanian

6 MW flat-top regime


Adjusting PFN Coil with real Load

Interlock Testing

Klystron Mounting &

Testing

PFN Tuning, Power Supply , Cathode

conditioning, Shielding,

Cabling, Preamplifier

Modulator & Preamplifier Preparation works

Move to tunnel

Mounting & Testing

Interlock Testing•.•.•.•.•.

Measurements

RF

Stat

ion

Rea

dy

19

.09

.20

12

Waveguides delivery

8/O

ct

26

/Oct

26

/No

v

HV ON

Integration wit other subsystemsCooling Vacuum

Radiation SafetyInterlock Integration

15

/Oct

LLRF Impl.

Measurement of Klystron Working Parameters for FF

table (Gain, saturation, etc…

)

Prep. Klystron start

17

/Dec

Sep Oct Nov Dec Jan

40 41 42 43 44 45 46 47 48 493938 50 51 52 1

Oil tank

ready

Ordering VNA Cables and Calibration Unit

5/N

ov

Klystron resonator measurement for

optimal Temperature

Klystron START

without LLRF

LLRF test

Ordering missing parts

Stage 1

12

/No

v8

/Oct

2 0 1 2 Presented on 19.09.2012

Klystron Start Preparation Works

29


Inte

rlo

ck T

esti

ng

Mo

un

tin

g &

Tes

tin

g M

easu

rem

ents

Mo

ve t

o t

un

nel

Jan Feb Mar Apr May Jun Jul Aug Sep

RF

Rea

dy

Tod

ay

18

/Ap

r

PFN

Tu

nin

g

Inte

grat

ion

wit

oth

er s

ub

sist

ems

LLR

F Im

pl.

LLR

F te

st

Pre

p. K

lyst

ron

sta

rt1

/Sep

30

Stage 1

2 0 1 3

K211 mod. coax x2 50

Ohm

Network 220 V

RACK - 1

Remote Control

Main Trigger

Klystron Heater

HeaterPower supply

TH2436 Modulator Power supply

Index Volts / Amperes

K211 mod. coax x250 Ohm TH2436

mod. coax 50 Ohm

K211 klystron

K211 klystron solenoid

TH2436 mod.

±12,24,130,250 V

K211 klystron coax x2 V-A

TH2436klystroncoax x2

V-A

Main Trigger

K211 mod. 24

pole

1 or 2 Hz

thyratrons’ driver

Wiring of Subsystems


AC

transformer K211

K211 modulator

K211 mod.coax x2 50 Ohm

K211 mod. 24 pole

K211 klystron coax x2 V-A

thyratron

driver

K211 mod. coax x250 Ohm

K2117 MW

TH2436 klystroncoax x2 V-A

TH2436 mod.±12,24,130,250 V

thyratron driverTH2436 mod. coax 50 Ohm

TH2436modulator

TH243610 KW

K211 klystronsolenoid

K211 klystron heater

Network 220 V

Network220 V

Wiring of Subsystems

32


• The majority of the tasks defined for our group were performed according to the schedule. The critical issue remains the problem of timing which we plan to solve via simple time delays.

• An important problem we haven’t yet paid enough attention to is the automatic synchronization of the laser and RF, which at the first phase we plan to perform manually.

• The analog interlock system is implemented and tested which will protect the accelerator and the RF station.

• An additional digital interlock system for the RF system is required. The Digital Interlock System (based on programmable logic devices) will be implemented after the LINAC first stage completion and upon necessity it can be easily modified during operation.

Conclusion

33

Thank You for Attention!!!

34

Documents

Areal RF Stationcandle.am/.../uploads/2015/05/TAC-2013-ArealRFStation.pdfAcharyan 31, 0040, Yerevan, Armenia Tel / FAX (+374-10) - 629806 RF System 2 The AREAL RF system will consist