Status of the PS TFB

Status of the PS Status of the PS TFBTFB

J. Belleman, E. Benedetto, F. Caspers, D. Glenat, R. Louwerse,

M. Martini, E. Métral, V. Rossi, J. Sladen, J.M. Nonglaton

Acknowledgments:

R. Steerenberg, S. Gilardoni

1. Hardware Overview2. Machine results3. To be done

Alfred Blas APC 30/1/2009APC 30/1/2009 11

PS TFBPS TFB

Green boxes represent devices to be completed

Block diagram


PS TFBPS TFB

Kickers + transformers PS SS 97Power + electronics 355-R-017 Water distribution 355-R-017

Clock distribution PS CB

Hardware setup


PS TFBPS TFB Pick-up amplifiers J. Belleman

BW: 20 kHz – 40 MHz80 dB dynamic range (compatible with ions)

Remotely programmable gain

Located in the ring below concrete slab


PS TFBPS TFB DSPU hardware V. Rossi


PS TFBPS TFB DSPU firmware


Green boxes represent functions to be completed

PS TFBPS TFB

1 GHz DDSReceives the frequency program from the PS central building and outputs the 160*Frev (< 80 MHz).

Clock GeneratorTransforms 10 MHz into 1 GHz

Clock generation J. Sladen


PS TFBPS TFB Pre-Amplifier

Fast Clipping of the output signal

0 and 180o outputs

Programmable gain

TFM setup

Local / Remote control

Interface with the PLC control


PS TFBPS TFB Power Amplifier R. Louwerse

[2.5 kHz – 25 MHz], 3kW – 2ms, 800W – CW


PS TFBPS TFB Impedance matching transformers R. Louwerse

Input impedance: 50 ΩOutput impedance: 100 Ω [ 2kHz – 40 MHz] 3 kW


PS TFBPS TFB Kicker F. Caspers, V. Bretin


PS TFBPS TFB Kicker


PS TFBPS TFB Power loads

50 Ω / 30 dB Attenuator[ DC – 1GHz] 1 kW CW

100Ω to 50Ω resistive transition[ DC – 190 MHz] 1.6 kW CW


PS TFBPS TFB PLC Power Control D. Glenat


PS TFBPS TFB

Operation display

J. M. Nonglaton


PS TFBPS TFBResults: Automatic delay

•Resolution=0.4ns

•Measurement time: 22 us

•Maximum jitter : 260 ps

•Precision requirement:

1.1 ns for 10o error at 25 MHz


PS TFBPS TFB Machine Results Auto Dly + Hilbert

The proper functioning of the automatic delay has been tested during an MD on MDPS (22/09/08) with a copy of the SFTPRO beam.

The beam transfer function was measured on the 3.5 GeV plateau and on the 14 GeV plateau.

If the phase response of all betatron lines can be superimposed, the delay is correct. The parameters of the automatic delay were set at 3.5 GeV for a proper phase response and the measurements made again at 14 GeV proved that the circuit behaved as expected.The measurements made another day at 1.4 GeV gave the same positive results.BTF of a Q+q betatron line


PS TFBPS TFB Results: Notch Filter


PS TFBPS TFB Results: Hilbert Filter

Without Notch Filter – set value = 45o With Notch Filter – set value = 45o

M= 3 Hilbert


PS TFBPS TFB Results: Hilbert Filter

Without Notch Filter – set value = 45o With Notch Filter – set value = 45o

M= 1 Hilbert


PS TFBPS TFB Sensitivity to Q measurement

With the PU in SS98 and the kicker in SS97, the ideal betatron phase lag within the TFB path can be

expressed as follow (qH,V Є [0 , 0.5]):

ΔφB-TFB = -111.6o + (536.4o * q) in the case of no delay for the dephasing (2 PUs!)

ΔφB-TFB = -111.6o + (896.4o * q) in the case of 1TREV delay for the dephasing (m=1 Hilbert)

ΔφB-TFB = -111.6o + (1616.4o * q) in the case of 3TREV delay for the dephasing (m=3 Hilbert)

9o phase error for an error in q of 0.01 with the m=1 Hilbert

( <=> 4.5 kHz error in the FFT)

One measurement made on LHC25. 11/11/08

The Q measurements are supposed to have a precision of 100ppmUnfortunately during the tests we had a jitter from cycle to cycleThe rf clock of the Q measurement doesn’t take into account the loop errors of the RFLL.Is this the explanation?


PS TFBPS TFB Results

500 μs/div

30mm p-p initial H error MDPS 1.4 GeV flat cycle with no Chromaticity and no coupling23/10/08

PSB MD1 beam 55.1010 p injected (3 turns in R3)

Injection error obtained by setting PI.KFA45 to 270 kV instead of 300 kV

Inj. error Damping: 20mm/ms @ 1.4 GeV (21mm/ms required for the most demanding case: Pilot beam εn = 0.8μm)

Power system used for controlled blow-up (slow extraction) and Q measurement

From M. MartiniAPC 26/5/2005


PS TFBPS TFB Results

500 μs/div

30mm p-p initial H error


Zoom top = h position bottom = kick 2μs/div

PS TFBPS TFB Results MD 11/11/2008 E. Metral

•LHC25 injection plateau at 1.4 GeV with linear H/V coupling (Iskew =-0.3)

•Without coupling (Iskew = +0.3)

•See logbook for more details (11/11/08)

•Last plot taken from a good shot; not always the case

(The Betatron phase was set to an empirical fixed value!)


With coupling – No TFB Without coupling – No TFB

Without coupling – With TFB

PS TFBPS TFB Results MD 11/12/2008

•Q measurement


Without coupling – No TFB

Only the H plane is excited

PS TFBPS TFBThe MDs on the machine show that the PSTFB fulfills the expected requirements:

Kick efficiency Automatic delay Hilbert filter Remote control of the DSPU and of the Power system Usage of the power system for the Q measurements and controlled blow-up

Improvements for 2009:

Hardware 2 fully loaded DSPU modules instead of the single beta version. 2nd input on the DSPU with a serial delay for the 2nd PU. ( -> lower sensitivity to Q value) 3rd and 4th inputs on the DSPU for the PU SUM signals (normalization of the Delta signal) DSPU input impedance varies with the input attenuation (52 -> 72Ω) Install a driver for a better compatibility with the Q measurement excitation

Firmware Notch filter could be modified for a more suitable phase response Q-to-Hilbert-phase LUT should be adapted to take into account the phase errors of the Hilbert (with respect to the command) together with the response of the Notch.

Software Q (h and V) measured along the cycle (0.01 precision) and value sent to a GFAS (PA.GSTFBH and PA.GSTFBV) PU control knob to be created (Automatic gain as a function of peak beam intensity ?)

Other Q measurement (rev clock used for the sampling of the beam signal precise enough ?)

Conclusion


Status of the PS TFB

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