TY  - CONF
AU  - Kim, M.J.
AU  - Choi, Choi.
AU  - Han, J.H.
AU  - Jeong, S.-H.
AU  - Jung, Y.G.
AU  - Kang, H.-S.
AU  - Kim, D.E.
AU  - Kim, M.S.
AU  - Lee, H.-G.
AU  - Lee, S.B.
AU  - Lee, S.J.
AU  - Oh, B.G.
AU  - Park, K.-H.
AU  - Suh, H.S.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Design of Analog to Digital Converter Scheme for High - Precision Electromagnet Power supply
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - This paper deals with the design of an analogue-to-digital converter (ADC) scheme for a highly precise magnet current supply (MPS). The MPSs are requires with stable and precise current specification in range of the ppm. To meet the requirements, the AD circuit is composed of parallel ADCs of low-medium resolution. Digitally, the oversampling and averaging are performed to increase both the effective resolution and the signal to noise ratio (SNR). The implemented AD circuit was improved about 18 dB (32 times oversampling). The MPS applied by the proposed ADC scheme provides more precise control and the stable current within 10 ppm at 200 A. The experiment used a dipole magnet of the PAL-XFEL and its results proved feasibility through precisely measurable DVM3458A (Keysight Co.).
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 1309
EP  - 1311
KW  - controls
KW  - FEL
KW  - hardware
KW  - experiment
KW  - dipole
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-TUPMP032
UR  - http://jacow.org/ipac2019/papers/tupmp032.pdf
ER  - 

TY  - CONF
AU  - Park, S.J.
AU  - Cha, S.C.
AU  - Hwang, J.H.
AU  - Kim, D.H.
AU  - Park, Y.J.
AU  - Yu, D.H.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Beam Loss Suppression by Beam Matching in Klystron
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - High power klystrons usually employ large cathodes to generate high currents which are compressed inside the gun to provide optimum beam sizes at the cavity section. We compress the beam by using electrostatic and magnetostatic focusing fields which are established by gun electrodes and external magnets respectively. The geometry of the gun elecrodes and the external magnet is carefully designed to meet the matching condition which results in scalloping-free beam. We have established a systematic design procedures to achieve the beam matching condition at arbitrary beam sizes. In this article we report on the beam-matching design and simulation results with an example case of the 80-MW S-band klystron in the Pohang Accelerator Laboratory.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 4218
EP  - 4220
KW  - klystron
KW  - simulation
KW  - gun
KW  - beam-losses
KW  - injection
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-THPTS052
UR  - http://jacow.org/ipac2019/papers/thpts052.pdf
ER  -