IPAC2017 - List of Authors (Malmgren, L.)

Paper	Title	Page
THPAB135	Digital LLRF for MAX IV	4037
	A. Salom, F. Pérez ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain Å. Andersson, R. Lindvall, L. Malmgren, A.M. Milan, A.M. Mitrovic MAX IV Laboratory, Lund University, Lund, Sweden
	The MAX IV facility consists of a 3 GeV Storage Ring(SR), a 1.5 GeV SR, and a linear accelerator (fed by two guns) that serves as a full-energy injector to the rings, but also as a driver for the Short Pulse Facility. The RF systems of the two SRs work at 100MHz. There are 6 normal conducting capacity loaded accelerating cavities and three Landau passive cavities in the 3GeV SR. In the 1.5GeV SR there are two accelerating cavities and two Landau cavities with the same characteristics. Each of these cavities is fed by a modular 60kW SSA. In the 3 GeV SR the power will be doubled by adding a second SSA when required. A digital Low Level RF system has been developed using commercial uTCA boards, with a Virtex-6 FPGA mother board (Perseus 601X) and two double stack FMC boards with fast ADCs and DACs. The large capabilities of state-of-the-art FPGAs allowed including the control of two normal conducing cavities and two landau cavities in one single LLRF system, reducing the development costs. Other utilities like the handling of fast interlocks and post-mortem analysis were also added to this system. This paper summarizes the main capabilities and performance of this DLLRF.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPAB135
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THPIK086	Design and Implementation of Stripline Feedback Kickers in the MAX IV 3 GeV Ring	4285
	D. Olsson, L. Malmgren, K. Åhnberg MAX IV Laboratory, Lund University, Lund, Sweden
	The commissioning of a bunch-by-bunch feedback system for the MAX IV 3 GeV storage ring was started in early 2016. At date, the actuators are two stripline kickers oriented in the horizontal and in the vertical plane, respectively. Apart from providing feedback in the transverse plane, the horizontal stripline is simultaneously operating as a longitudinal kicker. This is done by upconverting the longitudinal 0 - 50 MHz baseband signal to the 150 MHz - 250 MHz range where the longitudinal shunt impedance of the stripline is higher. This signal is then fed to the stripline electrodes in common-mode. The design of the stripline kickers and the layout of the bunch-by bunch feedback system in the 3 GeV ring are presented in this report. Results from instability studies in this ring are also discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPIK086
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THPIK087	A Waveguide Overloaded Cavity Kicker for the MAX IV Bunch-by-Bunch Feedback System	4289
	D. Olsson, L. Malmgren, K. Åhnberg MAX IV Laboratory, Lund University, Lund, Sweden
	The higher-order modes (HOMs) in the main and the 3:rd harmonic cavities are driving longitudinal coupled-bunch mode instabilities (CBMIs) in the MAX IV 3 GeV storage ring. This far, negative feedback has been applied in the longitudinal plane by a stripline kicker at lower ring currents. However, the maximum longitudinal feedback voltage provided by the stripline is rather weak, and a waveguide overload cavity was therefore designed in order to suppress CBMIs at higher ring currents as well. Due to the long bunch length in the MAX IV storage rings, a relatively low center frequency of 625 MHz is selected. The new cavity kicker has been manufactured, and will be installed in the 3 GeV ring during the summer shut-down of 2017. In this paper, the RF and mechanical design of the cavity is presented. Simulation results are also compared with measurements of the manufactured cavity.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPIK087
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Paper

Title

Page

Digital LLRF for MAX IV

4037

A. Salom, F. Pérez
ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
Å. Andersson, R. Lindvall, L. Malmgren, A.M. Milan, A.M. Mitrovic
MAX IV Laboratory, Lund University, Lund, Sweden

The MAX IV facility consists of a 3 GeV Storage Ring(SR), a 1.5 GeV SR, and a linear accelerator (fed by two guns) that serves as a full-energy injector to the rings, but also as a driver for the Short Pulse Facility. The RF systems of the two SRs work at 100MHz. There are 6 normal conducting capacity loaded accelerating cavities and three Landau passive cavities in the 3GeV SR. In the 1.5GeV SR there are two accelerating cavities and two Landau cavities with the same characteristics. Each of these cavities is fed by a modular 60kW SSA. In the 3 GeV SR the power will be doubled by adding a second SSA when required. A digital Low Level RF system has been developed using commercial uTCA boards, with a Virtex-6 FPGA mother board (Perseus 601X) and two double stack FMC boards with fast ADCs and DACs. The large capabilities of state-of-the-art FPGAs allowed including the control of two normal conducing cavities and two landau cavities in one single LLRF system, reducing the development costs. Other utilities like the handling of fast interlocks and post-mortem analysis were also added to this system. This paper summarizes the main capabilities and performance of this DLLRF.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPAB135

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THPIK086

Design and Implementation of Stripline Feedback Kickers in the MAX IV 3 GeV Ring

4285

D. Olsson, L. Malmgren, K. Åhnberg
MAX IV Laboratory, Lund University, Lund, Sweden

The commissioning of a bunch-by-bunch feedback system for the MAX IV 3 GeV storage ring was started in early 2016. At date, the actuators are two stripline kickers oriented in the horizontal and in the vertical plane, respectively. Apart from providing feedback in the transverse plane, the horizontal stripline is simultaneously operating as a longitudinal kicker. This is done by upconverting the longitudinal 0 - 50 MHz baseband signal to the 150 MHz - 250 MHz range where the longitudinal shunt impedance of the stripline is higher. This signal is then fed to the stripline electrodes in common-mode. The design of the stripline kickers and the layout of the bunch-by bunch feedback system in the 3 GeV ring are presented in this report. Results from instability studies in this ring are also discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPIK086

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THPIK087

A Waveguide Overloaded Cavity Kicker for the MAX IV Bunch-by-Bunch Feedback System

4289

D. Olsson, L. Malmgren, K. Åhnberg
MAX IV Laboratory, Lund University, Lund, Sweden

The higher-order modes (HOMs) in the main and the 3:rd harmonic cavities are driving longitudinal coupled-bunch mode instabilities (CBMIs) in the MAX IV 3 GeV storage ring. This far, negative feedback has been applied in the longitudinal plane by a stripline kicker at lower ring currents. However, the maximum longitudinal feedback voltage provided by the stripline is rather weak, and a waveguide overload cavity was therefore designed in order to suppress CBMIs at higher ring currents as well. Due to the long bunch length in the MAX IV storage rings, a relatively low center frequency of 625 MHz is selected. The new cavity kicker has been manufactured, and will be installed in the 3 GeV ring during the summer shut-down of 2017. In this paper, the RF and mechanical design of the cavity is presented. Simulation results are also compared with measurements of the manufactured cavity.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPIK087

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reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)