IPAC2019 - List of Authors (Wu, Y.)

Paper	Title	Page
THPRB041	Design a Precise Stability Controller for High Power Pulse Modulator Based on FPGA	3900
THPRB040	use link to see paper's listing under its alternate paper code
	Y.F. Liu, Z.H. Chen, M. Gu, J. Tong, Y. Wu, Q. Yuan, X.X. Zhou SINAP, Shanghai, People’s Republic of China
	Shanghai Soft X-ray Free Electron Laser (SXFEL) facility is under testing at Shanghai Institute of Applied Physics (SINAP), Chinese Academy of Sciences. The stability of RF system is one of the major factors to get great beam performance. It is mainly determined by klystron modulators power supply. The beam voltage of the LINAC klystron modulator, which is the pulsed power source of the RF amplifier, is directly affecting the RF amplitude and phase. This paper shows the suitable upgrade scheme of the modulator power supply and design considerations for the stability improvement of modulator power supply for Shanghai SXFEL. We present a real time feedback control system of LINAC pulse modulator to improve pulse to pulse amplitude stability. The feedback control system is based on the principle of embedded FPGA techniques. The control system consists of an embedded NIOS II processor, a High resolution ADC and an upper computer. The NIOS II processor manage on chip FIFO, ADC, IRQ, and Ethernet. The relevant experiments indicate that the feedback control strategy reaches required function. It is useful to improve the stability of existing modulator power supply.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-THPRB041
About •	paper received ※ 21 April 2019 paper accepted ※ 21 May 2019 issue date ※ 21 June 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPRB042	Stability Research Progress on High-power Pulse Modulator for SXFEL-UF	3904
	Q. Yuan, M. Gu, Y.F. Liu, J. Tong, Y. Wu SINAP, Shanghai, People’s Republic of China
	Funding: Supported by the National Natural Science Foundation of China(11675250) Abstract: SXFEL-UF(Shanghai Soft X-ray Free Electron Laser User Facility) under construction presently demands higher energy stability. Stability of pulse modulator feeding power for klystron plays an utmost important role in energy stability and occupy dominant factors in bringing influences in stability of RF power. Presently, stability of high-power pulse modulator of LINAC (Linear Accelerator) is on the level of 0.1% to 0.05% usually. In order to meet the higher stability requirements, it is very necessary for close-loop feedback control techniques instead of traditional open-loop to be applied in the modulator design. The stability controller adopts double control-loops techniques which feedback signals are respectively from PFN(Pulse Forming Network) and pulse transformer in oil tank. In addition, the paper also introduces recent progress on high stability CCPS research(Capacitor Charging Power Supply), which brings direct impact on the stability of modulator. In comparison with the former close-loop design, high stability CCPS design takes the overall modulator stability into full consideration. And the feedback control algorithm utilized to adjust PWMs for full bridge switch is implemented in the CCPS controller directly rather than modulator controller independent of CCPS. It is expected to obtain 0.01% stability by taking the above measures.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-THPRB042
About •	paper received ※ 06 May 2019 paper accepted ※ 23 May 2019 issue date ※ 21 June 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

THPRB041

Design a Precise Stability Controller for High Power Pulse Modulator Based on FPGA

3900

THPRB040

use link to see paper's listing under its alternate paper code

Y.F. Liu, Z.H. Chen, M. Gu, J. Tong, Y. Wu, Q. Yuan, X.X. Zhou
SINAP, Shanghai, People’s Republic of China

Shanghai Soft X-ray Free Electron Laser (SXFEL) facility is under testing at Shanghai Institute of Applied Physics (SINAP), Chinese Academy of Sciences. The stability of RF system is one of the major factors to get great beam performance. It is mainly determined by klystron modulators power supply. The beam voltage of the LINAC klystron modulator, which is the pulsed power source of the RF amplifier, is directly affecting the RF amplitude and phase. This paper shows the suitable upgrade scheme of the modulator power supply and design considerations for the stability improvement of modulator power supply for Shanghai SXFEL. We present a real time feedback control system of LINAC pulse modulator to improve pulse to pulse amplitude stability. The feedback control system is based on the principle of embedded FPGA techniques. The control system consists of an embedded NIOS II processor, a High resolution ADC and an upper computer. The NIOS II processor manage on chip FIFO, ADC, IRQ, and Ethernet. The relevant experiments indicate that the feedback control strategy reaches required function. It is useful to improve the stability of existing modulator power supply.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-THPRB041

About •

paper received ※ 21 April 2019 paper accepted ※ 21 May 2019 issue date ※ 21 June 2019

Export •

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

THPRB042

Stability Research Progress on High-power Pulse Modulator for SXFEL-UF

3904

Q. Yuan, M. Gu, Y.F. Liu, J. Tong, Y. Wu
SINAP, Shanghai, People’s Republic of China

Funding: Supported by the National Natural Science Foundation of China(11675250)
Abstract: SXFEL-UF(Shanghai Soft X-ray Free Electron Laser User Facility) under construction presently demands higher energy stability. Stability of pulse modulator feeding power for klystron plays an utmost important role in energy stability and occupy dominant factors in bringing influences in stability of RF power. Presently, stability of high-power pulse modulator of LINAC (Linear Accelerator) is on the level of 0.1% to 0.05% usually. In order to meet the higher stability requirements, it is very necessary for close-loop feedback control techniques instead of traditional open-loop to be applied in the modulator design. The stability controller adopts double control-loops techniques which feedback signals are respectively from PFN(Pulse Forming Network) and pulse transformer in oil tank. In addition, the paper also introduces recent progress on high stability CCPS research(Capacitor Charging Power Supply), which brings direct impact on the stability of modulator. In comparison with the former close-loop design, high stability CCPS design takes the overall modulator stability into full consideration. And the feedback control algorithm utilized to adjust PWMs for full bridge switch is implemented in the CCPS controller directly rather than modulator controller independent of CCPS. It is expected to obtain 0.01% stability by taking the above measures.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-THPRB042

About •

paper received ※ 06 May 2019 paper accepted ※ 23 May 2019 issue date ※ 21 June 2019

Export •

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