IBIC2017 - List of Authors (Carwardine, J.)

Paper	Title	Page
TUPCF02	Modeling the Fast Orbit Feedback Control System for APS Upgrade	196
	P.S. Kallakuri, N.D. Arnold, J. Carwardine, D.R. Paskvan, N. Sereno ANL, Argonne, Illinois, USA
	Funding: Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-AC02-06CH11357 The expected beam sizes for APS Upgrade are in the order of 4 microns for both planes. Orbit stabilization to 10% of the beam size with such small cross-sections requires pushing the state of the art in fast orbit feedback control, both in the spatial domain and in dynamical performance; the latter being the subject of this paper. In this paper, we begin to study possible performance benefits of moving beyond the classic PID regulator to more sophisticated methods in control theory that take advantage of a-priori knowledge of orbit motion spectra and system non-linearities. A reliable model is required for this process. Before developing a predictive model for the APS Upgrade, the system identification methodology is tested and validated against the present APS storage ring. This paper presents the system identification process, measurement results, and discusses model validation.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2017-TUPCF02
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TUPCF04	Feedback Controller Development for the APS-MBA Upgrade	203
	H. Bui, N.D. Arnold, A.R. Brill, J. Carwardine, G. Decker, T. Fors, R.M. Lill, D.R. Paskvan, A.F. Pietryla, N. Sereno, S.E. Shoaf, S. Veseli, S. Xu ANL, Argonne, Illinois, USA
	The Advanced Photon Source (APS) is currently in the preliminary design phase for the multi-bend achromat (MBA) lattice upgrade. Broadband Root Mean Square (rms) orbit motion should stay within 10% of a beam cross-section of the order 4μm x 4μm rms at the insertion device source-points. In order to meet these stringent AC beam stability requirements, a new orbit feedback system is under development and is being tested on the existing APS storage ring. The controller prototype uses Commercial Off-The-Shelf (COTS) hardware that has both high-performance Xilinx Field-Programmable Gate Array (FPGA) and two high-performance Texas-Instruments Digital Signal Processors (DSP) onboard. In this paper, we will discuss the rationale for a combined DSP/FPGA architecture and how functions are allocated. We then present the FPGA architecture and the results of using Infinite Impulse Response (IIR) filtering to mitigate Beam Position Monitor (BPM) switching noise and aliasing.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2017-TUPCF04
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WEPCF06	R&D Progress on Precision Current Monitoring and Calibration Systems for the APS Upgrade Unipolar Magnet Power Supplies	428
	R.T. Keane, J. Carwardine, B. Deriy, T. Fors, J. Wang ANL, Argonne, Illinois, USA
	Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under contract DE-AC02-06CH11357 The APS Upgrade storage ring multi-bend acromat lattice uses 1000 individually-powered multi-pole magnets operating at current levels to ~260A. Requirements for power-supply stability, repeatability and reproducibility are of the order of 10 ppm. MBA SR q u a d m a g n e t a n d Q - b e n d dipole magnet current regulation will require a higher level of accuracy, precision, stability, and independent control than existing APS systems. In order to meet these requirements, the upgrade will include the installation of 1000 new unipolar power supplies. To monitor and ensure the performance of the power supplies, an independent precision current measurement system is under development, based on a commercially available DCCT sensor. An in-situ calibration system is also required that will maintain the ensemble accuracy of the measurement system and magnet-to-magnet relative calibration by providing precise known calibration current to each of the 1000 DCCTs distributed around the 1100-meter ring. R&D on the in-situ cross-calibration scheme is being performed using a network of 6-8 full-spec DCCTs. This paper discusses the proposed approach, and results and lessons from the R&D program.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2017-WEPCF06
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Paper

Title

Page

Modeling the Fast Orbit Feedback Control System for APS Upgrade

196

P.S. Kallakuri, N.D. Arnold, J. Carwardine, D.R. Paskvan, N. Sereno
ANL, Argonne, Illinois, USA

Funding: Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-AC02-06CH11357
The expected beam sizes for APS Upgrade are in the order of 4 microns for both planes. Orbit stabilization to 10% of the beam size with such small cross-sections requires pushing the state of the art in fast orbit feedback control, both in the spatial domain and in dynamical performance; the latter being the subject of this paper. In this paper, we begin to study possible performance benefits of moving beyond the classic PID regulator to more sophisticated methods in control theory that take advantage of a-priori knowledge of orbit motion spectra and system non-linearities. A reliable model is required for this process. Before developing a predictive model for the APS Upgrade, the system identification methodology is tested and validated against the present APS storage ring. This paper presents the system identification process, measurement results, and discusses model validation.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2017-TUPCF02

Export •

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

TUPCF04

Feedback Controller Development for the APS-MBA Upgrade

203

H. Bui, N.D. Arnold, A.R. Brill, J. Carwardine, G. Decker, T. Fors, R.M. Lill, D.R. Paskvan, A.F. Pietryla, N. Sereno, S.E. Shoaf, S. Veseli, S. Xu
ANL, Argonne, Illinois, USA

The Advanced Photon Source (APS) is currently in the preliminary design phase for the multi-bend achromat (MBA) lattice upgrade. Broadband Root Mean Square (rms) orbit motion should stay within 10% of a beam cross-section of the order 4μm x 4μm rms at the insertion device source-points. In order to meet these stringent AC beam stability requirements, a new orbit feedback system is under development and is being tested on the existing APS storage ring. The controller prototype uses Commercial Off-The-Shelf (COTS) hardware that has both high-performance Xilinx Field-Programmable Gate Array (FPGA) and two high-performance Texas-Instruments Digital Signal Processors (DSP) onboard. In this paper, we will discuss the rationale for a combined DSP/FPGA architecture and how functions are allocated. We then present the FPGA architecture and the results of using Infinite Impulse Response (IIR) filtering to mitigate Beam Position Monitor (BPM) switching noise and aliasing.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2017-TUPCF04

Export •

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

WEPCF06

R&D Progress on Precision Current Monitoring and Calibration Systems for the APS Upgrade Unipolar Magnet Power Supplies

428

R.T. Keane, J. Carwardine, B. Deriy, T. Fors, J. Wang
ANL, Argonne, Illinois, USA

Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under contract DE-AC02-06CH11357
The APS Upgrade storage ring multi-bend acromat lattice uses 1000 individually-powered multi-pole magnets operating at current levels to ~260A. Requirements for power-supply stability, repeatability and reproducibility are of the order of 10 ppm. MBA SR q u a d m a g n e t a n d Q - b e n d dipole magnet current regulation will require a higher level of accuracy, precision, stability, and independent control than existing APS systems. In order to meet these requirements, the upgrade will include the installation of 1000 new unipolar power supplies. To monitor and ensure the performance of the power supplies, an independent precision current measurement system is under development, based on a commercially available DCCT sensor. An in-situ calibration system is also required that will maintain the ensemble accuracy of the measurement system and magnet-to-magnet relative calibration by providing precise known calibration current to each of the 1000 DCCTs distributed around the 1100-meter ring. R&D on the in-situ cross-calibration scheme is being performed using a network of 6-8 full-spec DCCTs. This paper discusses the proposed approach, and results and lessons from the R&D program.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2017-WEPCF06

Export •

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