The RF Power Source for the High Beta Elliptical Cavities of the ESS Linac
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The RF Power Source for the High Beta Elliptical Cavities of the ESS Linac K. Rathsman, H. Danared, R. Zeng, ESS, Lund, Sweden R.J.M.Y. Ruber, Uppsala University, Sweden; C.A. Martins, Laval University, Canada C. Lingwood, Lancaster University, UK; A.J. Johansson, Lund University, Sweden Klystron Parameters High Power 704 MHz Parameter Minimum Nomina l Maximum Unit s RF Frequency 704.42 MHz Peak Output Power 1.0 1.2 1.5 MW RF Pulse length 3.3 ms Pulse repetition rate 14 Hz DC to RF efficiency 65 % Perveance 0.55 μPer v Beam Voltage 102 113 kV Beam current 18 21 A Parameter Minim um Nomi nal Maxim um Uni ts Peak power 1.5 1.8 2.3 MW Peak voltage 95 102 113 kV Pulse width 3.5 ms Pulse repetition rate 14 Hz Pulse rise time 0.2 ms Ripple (<100 Hz) & droop 3 % Ripple (0.1-1 kHz) 1 % Ripple (>1 kHz) 0.1 % Modulator Parameters High Power 704 MHz Parameter Unit Average beam power 5 MW Proton kinetic energy 2.5 GeV Average macro pulse current 50 mA Macro pulse length 2.8 6 ms Pulse Repetition Rate 14 Hz Maximum cavity surface field 40 MV/m Linac Length 392 m Annual operation period 520 0 h Reliability >95 % Losses <1 W/m Elliptical power coupler <0. Linac Parameters High power 704 MHz 112 High β Medium power 704 MHz 8 High β 36 Low β Low power 704 MHz 28 Low β Low power 352 MHz 28 Spoke 2 DTL 1 DTL 1 RFQ High power 352 MHz Klystron Modulator IOT / Solid state RF Source Scheme Power to Beam 1. 0 0. 8 0. 6 0. 4 0. 2 0. 0 0 50 100 150 200 250 300 350 Cavity Power (MW) Position (m) 28 Spokes 64 Low β 120 High β 28 28 44 112 Calculation by M. Eshraqi, WEPS062 RF Source Circulator LLRF Cavity load Klystron Modulator K l y s t r o n Surplus water Surplus water Surplus water 30% Sustainable Science Reliable Renewable, Responsible, Recyclable
description
Surplus water. Klystron Modulator. load. Surplus water. Surplus water. Klystron. Circulator. LLRF. Cavity. Power to Beam. RF Source Scheme. 1.0. 28 Spokes. 64 Low β. 120 Hi gh β. 2. 28. 28. 112. 36. 8. DTL. 112. Spoke. Low β. 0.8. Low β. High β. High β. - PowerPoint PPT Presentation
Transcript of The RF Power Source for the High Beta Elliptical Cavities of the ESS Linac
The RF Power Source for the High Beta Elliptical Cavities of the ESS Linac
K. Rathsman, H. Danared, R. Zeng, ESS, Lund, Sweden
R.J.M.Y. Ruber, Uppsala University, Sweden; C.A. Martins, Laval University, Canada
C. Lingwood, Lancaster University, UK; A.J. Johansson, Lund University, Sweden
Klystron ParametersHigh Power 704 MHz
Parameter Minimum Nominal Maximum Units
RF Frequency 704.42 MHz
Peak Output Power 1.0 1.2 1.5 MW
RF Pulse length 3.3 ms
Pulse repetition rate 14 Hz
DC to RF efficiency 65 %
Perveance 0.55 μPerv
Beam Voltage 102 113 kV
Beam current 18 21 A
RF Power Gain 48 dB
Bandwidth (-1 dB) 4 MHz
Cathode lifetime 100000 h
VSWR Tolerance 1.2:1
Parameter Minimum Nominal Maximum Units
Peak power 1.5 1.8 2.3 MW
Peak voltage 95 102 113 kV
Pulse width 3.5 ms
Pulse repetition rate 14 Hz
Pulse rise time 0.2 ms
Ripple (<100 Hz) & droop 3 %
Ripple (0.1-1 kHz) 1 %
Ripple (>1 kHz) 0.1 %
Pulse reproducibility 99.98 %
Energy in case of arc 10 J
Power efficiency 90 %
Undershoot voltage 10 %
Modulator ParametersHigh Power 704 MHz
Parameter Unit
Average beam power 5 MW
Proton kinetic energy 2.5 GeV
Average macro pulse current 50 mA
Macro pulse length 2.86 ms
Pulse Repetition Rate 14 Hz
Maximum cavity surface field 40 MV/m
Linac Length 392 m
Annual operation period 5200 h
Reliability >95 %
Losses <1 W/m
Elliptical power coupler power <0.9 MW
Linac Parameters
High power 704 MHz
112
High β
Medium power 704 MHz
8
High β
36
Low β
Low power 704 MHz
28
Low β
Low power 352 MHz
28
Spoke
2
DTL
1
DTL
1
RFQ
High power 352 MHz
Klystron Modulator IOT / Solid state
RF Source Scheme
Power to Beam1.0
0.8
0.6
0.4
0.2
0.00 50 100 150 200 250 300 350
Cav
ity
Pow
er (
MW
)
Position (m)
28 Spokes
64 Low β
120 High β
2828
44
112
Calculation by M. Eshraqi, WEPS062
RF Source
Circulator
LLRF
Cavity
loadKlystronModulator
Klystron
Sur
plus
wat
er
Sur
plus
wat
er
Sur
plus
wat
er
30%
Sustainable ScienceReliable Renewable, Responsible, Recyclable
