IPAC2012 - List of Authors (Yu, D.)

Paper	Title	Page
THPPC043	Cold Test of an L-band, 2-Cell PWT Photoelectron	3380
	Y. Luo, D. Yu DULY Research Inc., Rancho Palos Verdes, California, USA R. Andrews, T.N. Khabiboulline Fermilab, Batavia, USA
	Funding: DOE SBIR Grant No. DE-FG02-06ER84460 An L-band, 1+2/2-cell PWT gun with a coax coupler has been designed for high vacuum polarized electron source applications by DULY Research Inc. A cold test model was fabricated and is currently undergoing test at Fermilab, where the gun will eventually be hot tested. The aluminum cold test model includes an rf/ vacuum sieve, 2 disks, endplates, 6 supporting rods and a 6” CF flange, clamped together during testing. Fermilab made measurements for the cavity resonant frequency and axial field distribution using bead pull. To measure the resonant frequency of the cavity small diameter probes are placed through the vacuum sieve slot. A larger diameter probe can be used as an active tuner. This paper presents the results of the cold test and compares measurements with simulation results from 3D SLAC code Omega3p. The axial field distributions are in good agreement with each other. Frequency deviation is less than 0.5%, well within the experimental accuracy.

THPPD082	A Novel Solid-State Marx Modulator Topology with Voltage Droop Self-Compensation	3707
	P. Chen, M. Lundquist, D. Yu DULY Research Inc., Rancho Palos Verdes, California, USA
	Funding: Work supported by U.S. Department of Energy SBIR grant no. DE-FG02-08ER85052. Solid-state Marx modulators are preferred over conventional modulators in accelerators and radar applications because of their high flexibility, high reliability and long life. However, voltage droop is a notable issue. A novel topology of solid-state Marx modulators is described in this paper for raising their electric energy utilization ratios (EEURs). The new Marx modulator incorporates a buck regulator circuit into each Marx cell and adopts a higher charge voltage than that of application. The topology allows Marx cells to store more electric energy and utilize the energy more efficiently than others. Initial theoretical analysis and preliminary experiments show that solid-state Marx modulators constructed with this topology and under proper control of the stepwise energy release are able to significantly enhance their EEURs. The cost effective Marx modulators with compact energy storage sizes will resolve the issue of voltage droop when they are used in high power, long pulse applications.

Paper

Title

Page

Cold Test of an L-band, 2-Cell PWT Photoelectron

3380

Y. Luo, D. Yu
DULY Research Inc., Rancho Palos Verdes, California, USA
R. Andrews, T.N. Khabiboulline
Fermilab, Batavia, USA

Funding: DOE SBIR Grant No. DE-FG02-06ER84460
An L-band, 1+2/2-cell PWT gun with a coax coupler has been designed for high vacuum polarized electron source applications by DULY Research Inc. A cold test model was fabricated and is currently undergoing test at Fermilab, where the gun will eventually be hot tested. The aluminum cold test model includes an rf/ vacuum sieve, 2 disks, endplates, 6 supporting rods and a 6” CF flange, clamped together during testing. Fermilab made measurements for the cavity resonant frequency and axial field distribution using bead pull. To measure the resonant frequency of the cavity small diameter probes are placed through the vacuum sieve slot. A larger diameter probe can be used as an active tuner. This paper presents the results of the cold test and compares measurements with simulation results from 3D SLAC code Omega3p. The axial field distributions are in good agreement with each other. Frequency deviation is less than 0.5%, well within the experimental accuracy.

THPPD082

A Novel Solid-State Marx Modulator Topology with Voltage Droop Self-Compensation

3707

P. Chen, M. Lundquist, D. Yu
DULY Research Inc., Rancho Palos Verdes, California, USA

Funding: Work supported by U.S. Department of Energy SBIR grant no. DE-FG02-08ER85052.
Solid-state Marx modulators are preferred over conventional modulators in accelerators and radar applications because of their high flexibility, high reliability and long life. However, voltage droop is a notable issue. A novel topology of solid-state Marx modulators is described in this paper for raising their electric energy utilization ratios (EEURs). The new Marx modulator incorporates a buck regulator circuit into each Marx cell and adopts a higher charge voltage than that of application. The topology allows Marx cells to store more electric energy and utilize the energy more efficiently than others. Initial theoretical analysis and preliminary experiments show that solid-state Marx modulators constructed with this topology and under proper control of the stepwise energy release are able to significantly enhance their EEURs. The cost effective Marx modulators with compact energy storage sizes will resolve the issue of voltage droop when they are used in high power, long pulse applications.