IPAC2012 - List of Authors (Chen, J.-R.)

Paper	Title	Page
MOPPR053	Improvement of BPM System for the Siam Photon Source	903
	P. Songsiriritthigul, S. Boonsuya, S. Klinkhieo, P. Klysubun, S. Krainara, P. Sudmuang, N. Suradet SLRI, Nakhon Ratchasima, Thailand J.-R. Chen, H.P. Hsueh, Y.-H. Liu NSRRC, Hsinchu, Taiwan S. Rujirawat, P. Songsiriritthigul Suranaree University of Technology, Nakhon Ratchasima, Thailand
	The Siam Photon Source (SPS) is the first synchrotron light source ever built by modifying and relocating a light source from one country to another. The SPS produced its first light in Dec 2001. The machine has been used to provide regularly synchrotron light for users since 2005. Systematic studies and investigations of the machine have properly been carried out under the supervision of the International Advisory Committee of SLRI in the last two years. This report describes the improvement of the beam position monitoring (BPM) system for the 1.2 GeV storage ring of SPS. The efficiency and reliability of the original BPM system was greatly hindered by the low quality signal cables. The replacement with the higher quality (lower loss and better interference shielding) BPM cables and the implementation of a separated cable tray for the BPM cables have significantly improved the quality of the BPM signals, allowing the possibilities for machine study and thus providing further improvement of the machine. Detailed descriptions of the work on the BPM electronic boards will be described. The measurement results before and after the improvement of the BPM system will also be presented.

WEPPD019	Manufacturing and Welding Process of Straight Section of Aluminum Alloy UHV Chambers for Taiwan Photon Source	2537
	C.-C. Chang, C.K. Chan, C.L. Chen, J.-R. Chen, G.-Y. Hsiung, S-N. Hsu NSRRC, Hsinchu, Taiwan
	This paper describes the manufacturing process and welding sequence for the aluminum extrusion vacuum chamber for the straight sections in Taiwan Photon Source. The straight section composes of aluminum extrusion chamber of A6063 and BPM chamber of A6061 aluminum alloys. The straightness and flatness of these extrusion chambers are controlled under 0.1mm/m and 0.2mm/m, respectively. The BPM chambers are manufactured precisely in oil-free environment, which provide clean surface and a precise sealing surface after machining. All the components are assembled in pre-aligned support system through the welding process. The aluminum chamber for 24 straight sections has been welded. The results show the straightness of < 0.15mm/m, flatness of < 0.3mm/m, and leakage rates of < 2 × 10^-10 mbarl/sec. were achieved.

WEPPD020	Vacuum System for TPS Booster	2540
	C.M. Cheng, C.K. Chan, C.L. Chen, J.-R. Chen, G.-Y. Hsiung, S-N. Hsu, H.P. Hsueh NSRRC, Hsinchu, Taiwan
	The TPS booster is designed for lower beam emittance and 3GeV full energy injection ramped up from 150MeV. It is a synchrotron accelerator of 496.8m in circumference and located concentric with the electron storage ring in the same tunnel. The vacuum system for the booster is divided into six super periods and each has nine bending magnet chambers. The beam duct is made of thin stainless steel tube extruded to the elliptical cross section with inner diameters of 35 mm×20 mm and thickness of 0.7 mm. All the chambers will be supported on the inner wall of the tunnel. The straightness of the extruded thin chambers is controlled within 2.5 mm in 4 m length. The bending chamber is made by mechanical bending from the straight tube. All the beam ducts will be chemical cleaned prior to welding, with flanges or BPM chambers, to form the long chambers in the clean room before installation. The arrangement of vacuum pumps are distributed to fulfill an average pressure of ＜1×10^-6 Pa. The detailed design and the construction status will be described in the paper.

WEPPD021	Optimization of the Ultra-High Vacuum Systems for the 3 GeV TPS Synchrotron Light Source	2543
	G.-Y. Hsiung, C.K. Chan, C.-C. Chang, C.L. Chen, J.-R. Chen, C.M. Cheng, Y.T. Cheng, S-N. Hsu, H.P. Hsueh, Huang, Y.T. Huang, I.C. Sheng, L.H. Wu, Y.C. Yang NSRRC, Hsinchu, Taiwan
	The Taiwan Photon Source (TPS), a 3 GeV synchrotron light source, provides an ultra-low emittance of electron beam and the consequent extremely high brightness of photons. The vacuum pressure along the beam duct should be ultra-high vacuum (UHV) and even lower for reduction of the impact to the beam from the gas scattering or ion trapping troubles. Most of the outgas comes from the photon stimulated desorption (PSD) back streaming from downstream absorbers during beam operation and large area surface outgas inside the beam duct as well. Due to the anticipate request of the smallest vertical aperture of beam ducts from various insertion devices and the lowest broadband impedance through all the vacuum chambers of electron storage ring, the inner structure design and the surface treatment of vacuum chambers as well as the constraint of the back stream PSD outgas from distributed absorbers and the pumping locations should be optimized to obtain a high quality UHV system for the high stable synchrotron light source through the long period of operation. The optimized design of the vacuum chambers for the TPS will be described.

WEPPD022	Design of the Water-Cooling System for the Vacuum System of the TPS Storage Ring	2546
	Y.C. Yang, C.K. Chan, J.-R. Chen, C.M. Cheng, G.-Y. Hsiung NSRRC, Hsinchu, Taiwan
	Taiwan Photon Source (TPS) was under construction since 2009. TPS vacuum system was designed in 10^-10 torr level and gas load from synchrotron light was almost confined in bending chambers. A water cooling system was designed to protect vacuum equipment including vacuum chambers and absorbers to avoid melting down by synchrotron light. There are 3 cooling loops for aluminum chambers and 4 loops for cooper absorbers in one unit cell. One prototype for unit cell, including arrangement of control terminal, monitor of flow rate and temperature, and vibration from cooling system will be tested.

WEPPD023	Design and Manufacture of TPS BPM Diamond-Edge Gasket	2549
	Huang, Y.T. Huang, C.-C. Chang, C.L. Chen, J.-R. Chen, G.-Y. Hsiung, H.P. Hsueh NSRRC, Hsinchu, Taiwan
	TPS vacuum chamber is oil-free machined and the material is A6061T651 which the Brinell hardness is 95 kg/mm2. Beam position monitors are installed onto the bending chambers, B1 and B2 and the straight chambers, S3 and S4. The diamond-edge gasket was chosen to seal between BPM flange (SS316L) and the vacuum chamber (A6061T651). Easily manufactured, low cost and less clamping force are three main advantages of this diamond-edge gasket. This diamond-edge gasket is made of A1050H14 which has less hardness, 32 kg/mm2 and its surface roughness is well controlled under 0.8 μm because worse surface roughness probably lead to radial leak. Considering differences of thermal expansion between stainless steel and aluminium, SS304 set screws, nuts and washers are chosen to provide axial sealing force. The sealing ability of this diamond-edge gasket is reliable through tens of bake-out experiments. It is reminded that pre-torque should be sufficient to cause plastic deformation of the diamond-edge gasket and re-torque after baking 24hr and cooling down to room temperature is also important to prevent leaks resulting from loss of torque which usually happen at 100oC.

WEPPD024	A Study of Vacuum Pressure in TPS Cells	2552
	L.H. Wu, J.-R. Chen, C.M. Cheng, G.-Y. Hsiung, C.S. Huang, Huang, Y.T. Huang NSRRC, Hsinchu, Taiwan
	Recently, the type-2 and type-3 TPS cells are installed and pumped down into vacuum status. The pumping down curves of the type-2 and type-3cells, including R03, R06, R07, R10, and R11, are recorded after on-site welding and after assembling without leakage, individually. In the R03, R06, R07, R10 cells, the pumping down curve after assembling without leakage is a little higher than that after on-site welding. In those four cells, the pumping down curve after assembling all vacuum components and pumps is similar. However, in the R11 cell, it was found that the pumping down curve after assembling without leakage is almost along that of after on-site welding. The slope of pumping down curve near 1 hour in the R11 cell is -1.52, while that in the R10 cell is -1.39. It means that the vacuum pressure in the R11 cell is apparently improved. It is confirmed that the vacuum chambers are cleaned by the same process and the assembling components are similar. Besides, the photon stopper chambers are all pre-baked to 200 oC for the same time. We try to investigate the residual gas analysis (RGA) data to find the true reasons.

WEPPD039	Status of the Utility System Construction for the 3 GeV TPS Storage Ring	2597
	J.-C. Chang, W.S. Chan, J.-R. Chen, Y.F. Chiu, Y.-C. Chung, K.C. Kuo, Y.-C. Lin, C.Y. Liu, I. Liu, Z.-D. Tsai, T.-S. Ueng NSRRC, Hsinchu, Taiwan
	The construction of the utility system for the 3.0 GeV Taiwan Photon Source (TPS) was started in the end of 2009. The utility building for the TPS ring will be completed in the end of 2011. The whole construction of the utility system is scheduled to be completed in the end of 2012. Total budget of this construction is about four million dollars. This utility system presented in this paper includes the electrical power, cooling water, air conditioning, compressed air and fire control systems.

WEPPD042	The Grounding System at TPS	2606
	T.-S. Ueng, J.-C. Chang, J.-R. Chen, Y.-C. Lin NSRRC, Hsinchu, Taiwan
	An elaborately designed grounding system has been installed under the TPS construction site. The ground grid was installed sector by sector to comply with the building construction schedule. The ground resistance measurement of each sector was carried out right after the grid installation. The final ground resistance measurement for the whole grounding system was performed also right after its completion. The measured ground resistances of each sector were used to estimate the final TPS ground resistance, and it was compared to the final TPS ground measurement result. Also, the analysis with computer software is used to justify it. The low impedance of TPS grounding system, < 0.15 ohm, is to insure the safety of TPS personnel and instrumentation, also, to reduce the noise of electronic devices.

WEPPD045	An Application of Multi-stage Adjustable Shock Absorbers for the Girders of Storage Ring in Taiwan Photon Source	2615
	C.-S. Lin, J.-R. Chen, M.L. Chen, H.C. Ho, K.H. Hsu, D.-G. Huang, C.K. Kuan, W.Y. Lai, C.J. Lin, H.M. Luo, S.Y. Perng, P.L. Sung, Y.L. Tsai, T.C. Tseng, H.S. Wang, M.H. Wu NSRRC, Hsinchu, Taiwan D.-Y. Chiang NCKU, Tainan city, Taiwan
	Beam stability is a major concern for the operation of the Taiwan Photon Source (TPS). One of the many factors to instability of electron beam is mechanical vibration of the accelerator components. The TPS uses steel girders to support the magnets and vacuum chambers in the storage ring. Three pedestal and six mover assemblies support the girders. Multi-stage adjustable shock absorbers are designed for passive vibration damping, and presently installed between the girders and the pedestals. Through adjusting the amount of hydraulic fluid which bypasses the damping passage between two hydraulic chambers, the desired damping coefficient of the damping absorbers can be achieved. Experimental results of modal testing presented in this paper show that the multi-stage adjustable damping absorbers under the assembly of the girders reduced the level of girder vibration.

WEPPP087	The Improvement and Test of Laser Positioning System for TPS Magnets Alignment Inspection	2915
	M.L. Chen, J.-R. Chen, H.C. Ho, K.H. Hsu, W.Y. Lai, C.-S. Lin, C.J. Lin, H.C. Lin, H.M. Luo, S.Y. Perng, P.L. Sung, Y.L. Tsai, T.C. Tseng, H.S. Wang, M.H. Wu NSRRC, Hsinchu, Taiwan
	A Laser positioning system, consist of a laser, laser position sensing devices (PSD) module and two granite blocks, is developed for the alignment inspection of TPS (Taiwan Photon Source) quadrupole and sextupole magnets during installation on a girder. The PSD module is adapted on the pole center of magnet and is designed to stand for mechanical center of magnets. For high accuracy, eliminating the influence of magnets manufacturing errors between PSD module is a major work. The PSD is mounted on a precise diameter expansible jig to absorb the manufacturing errors. The real roundness of the expansible jig can keep under 3um when diameter is expanded 80um. The PSD position is adjusted and corrected in advance, and then the PSD module center can be identical to the ideal pole position of magnets on the girder within 15um. The magnet will be aligned and adjusted by laser position on PSD. This paper describes how to eliminate the measuring error caused by magnet manufacturing error and the detail of alignment inspection procedure of magnets during the installation on a girder.

WEPPP088	Auto-alignment System and CalibrationPprocedure in TPS Girder System	2918
	W.Y. Lai, J.-R. Chen, M.L. Chen, H.C. Ho, K.H. Hsu, D.-G. Huang, C.K. Kuan, C.-S. Lin, C.J. Lin, H.M. Luo, S.Y. Perng, P.L. Sung, Y.L. Tsai, T.C. Tseng, H.S. Wang, M.H. Wu NSRRC, Hsinchu, Taiwan
	The TPS (Taiwan photon source) project is under construction and will be finished in the December 2012. Considering the floor’s deformation with time and frequent earthquakes at Taiwan, the survey and alignment procedure should be taken quite often. For dealing with these difficulties and improving accuracy of girder’s position, a highly accurate auto-tuning girders system was designed to accomplish the alignment tasks. There are two cells of TPS girders and varied sensor modulus set up for testing the auto-tuning system. The adjustment of the system converges to less than 6um, and the repeatability of the testing is under 10 um. For improving the accuracy of girders position, that is critical thing to make sure all the calibration of sensors modulus correctly and accurately. The calibration procedure about sensor modular and testing results is described in this paper.

THPPD059	Conductive EMI Reduction to Kicker Magnet Power Supply in NSRRC	3647
	Y.-H. Liu, J.-C. Chang, C.S. Chen, H.H. Chen, J.-R. Chen NSRRC, Hsinchu, Taiwan
	The purpose of this paper is to estimate and reduce the conductive Electromagnetic Interference (EMI) from kicker magnet power supply in TLS. A LISN system was conducted to measure the EMI spectrum of kicker power supply. The EMI noise exceeded FCC standards in some frequency range especially during kicker firing. Reducing EMI level by using different EMI filters were applied. Double pi filter was more efficient than single pi filter. After using filter, the conducted EMI could diminish lower than FCC class B. The experimental results will provide useful information to future TPS pulsed magnet design.

WEPPP089	Study of the Combined Controller for Adjusting and Locking a Girder with Micrometer-level at NSRRC	2921
	H.S. Wang, M.L. Chen, W.Y. Lai, S.Y. Perng, Y.L. Tsai, T.C. Tseng NSRRC, Hsinchu, Taiwan J.-R. Chen NTHU, Hsinchu, Taiwan
	A girder control system is proposed to quickly and precisely adjust the displacement and rotating angle of all girders in the storage ring with little manpower at the Taiwan Photon Source (TPS) project at National Synchrotron Research Center (NSRRC). In this control girder system, six motorized cam movers supporting a girder are driven on three pedestals to perform six-axis adjustments of a girder. To increase the nature frequency of a girder, the locking system is applied to promote the stiffness of a girder structure. The locking system consists of six locking mechanisms attached to three inboard pedestals and a locking controller. The study of the girder control system and the locking system control combined are achieving to the positioning with micrometre-level. This paper presents details of the study and tests of the combined controller.

Paper

Title

Page

Improvement of BPM System for the Siam Photon Source

903

P. Songsiriritthigul, S. Boonsuya, S. Klinkhieo, P. Klysubun, S. Krainara, P. Sudmuang, N. Suradet
SLRI, Nakhon Ratchasima, Thailand
J.-R. Chen, H.P. Hsueh, Y.-H. Liu
NSRRC, Hsinchu, Taiwan
S. Rujirawat, P. Songsiriritthigul
Suranaree University of Technology, Nakhon Ratchasima, Thailand

The Siam Photon Source (SPS) is the first synchrotron light source ever built by modifying and relocating a light source from one country to another. The SPS produced its first light in Dec 2001. The machine has been used to provide regularly synchrotron light for users since 2005. Systematic studies and investigations of the machine have properly been carried out under the supervision of the International Advisory Committee of SLRI in the last two years. This report describes the improvement of the beam position monitoring (BPM) system for the 1.2 GeV storage ring of SPS. The efficiency and reliability of the original BPM system was greatly hindered by the low quality signal cables. The replacement with the higher quality (lower loss and better interference shielding) BPM cables and the implementation of a separated cable tray for the BPM cables have significantly improved the quality of the BPM signals, allowing the possibilities for machine study and thus providing further improvement of the machine. Detailed descriptions of the work on the BPM electronic boards will be described. The measurement results before and after the improvement of the BPM system will also be presented.

WEPPD019

Manufacturing and Welding Process of Straight Section of Aluminum Alloy UHV Chambers for Taiwan Photon Source

2537

C.-C. Chang, C.K. Chan, C.L. Chen, J.-R. Chen, G.-Y. Hsiung, S-N. Hsu
NSRRC, Hsinchu, Taiwan

This paper describes the manufacturing process and welding sequence for the aluminum extrusion vacuum chamber for the straight sections in Taiwan Photon Source. The straight section composes of aluminum extrusion chamber of A6063 and BPM chamber of A6061 aluminum alloys. The straightness and flatness of these extrusion chambers are controlled under 0.1mm/m and 0.2mm/m, respectively. The BPM chambers are manufactured precisely in oil-free environment, which provide clean surface and a precise sealing surface after machining. All the components are assembled in pre-aligned support system through the welding process. The aluminum chamber for 24 straight sections has been welded. The results show the straightness of < 0.15mm/m, flatness of < 0.3mm/m, and leakage rates of < 2 × 10^-10 mbarl/sec. were achieved.

WEPPD020

Vacuum System for TPS Booster

2540

C.M. Cheng, C.K. Chan, C.L. Chen, J.-R. Chen, G.-Y. Hsiung, S-N. Hsu, H.P. Hsueh
NSRRC, Hsinchu, Taiwan

The TPS booster is designed for lower beam emittance and 3GeV full energy injection ramped up from 150MeV. It is a synchrotron accelerator of 496.8m in circumference and located concentric with the electron storage ring in the same tunnel. The vacuum system for the booster is divided into six super periods and each has nine bending magnet chambers. The beam duct is made of thin stainless steel tube extruded to the elliptical cross section with inner diameters of 35 mm×20 mm and thickness of 0.7 mm. All the chambers will be supported on the inner wall of the tunnel. The straightness of the extruded thin chambers is controlled within 2.5 mm in 4 m length. The bending chamber is made by mechanical bending from the straight tube. All the beam ducts will be chemical cleaned prior to welding, with flanges or BPM chambers, to form the long chambers in the clean room before installation. The arrangement of vacuum pumps are distributed to fulfill an average pressure of ＜1×10^-6 Pa. The detailed design and the construction status will be described in the paper.

WEPPD021

Optimization of the Ultra-High Vacuum Systems for the 3 GeV TPS Synchrotron Light Source

2543

G.-Y. Hsiung, C.K. Chan, C.-C. Chang, C.L. Chen, J.-R. Chen, C.M. Cheng, Y.T. Cheng, S-N. Hsu, H.P. Hsueh, Huang, Y.T. Huang, I.C. Sheng, L.H. Wu, Y.C. Yang
NSRRC, Hsinchu, Taiwan

The Taiwan Photon Source (TPS), a 3 GeV synchrotron light source, provides an ultra-low emittance of electron beam and the consequent extremely high brightness of photons. The vacuum pressure along the beam duct should be ultra-high vacuum (UHV) and even lower for reduction of the impact to the beam from the gas scattering or ion trapping troubles. Most of the outgas comes from the photon stimulated desorption (PSD) back streaming from downstream absorbers during beam operation and large area surface outgas inside the beam duct as well. Due to the anticipate request of the smallest vertical aperture of beam ducts from various insertion devices and the lowest broadband impedance through all the vacuum chambers of electron storage ring, the inner structure design and the surface treatment of vacuum chambers as well as the constraint of the back stream PSD outgas from distributed absorbers and the pumping locations should be optimized to obtain a high quality UHV system for the high stable synchrotron light source through the long period of operation. The optimized design of the vacuum chambers for the TPS will be described.

WEPPD022

Design of the Water-Cooling System for the Vacuum System of the TPS Storage Ring

2546

Y.C. Yang, C.K. Chan, J.-R. Chen, C.M. Cheng, G.-Y. Hsiung
NSRRC, Hsinchu, Taiwan

Taiwan Photon Source (TPS) was under construction since 2009. TPS vacuum system was designed in 10^-10 torr level and gas load from synchrotron light was almost confined in bending chambers. A water cooling system was designed to protect vacuum equipment including vacuum chambers and absorbers to avoid melting down by synchrotron light. There are 3 cooling loops for aluminum chambers and 4 loops for cooper absorbers in one unit cell. One prototype for unit cell, including arrangement of control terminal, monitor of flow rate and temperature, and vibration from cooling system will be tested.

WEPPD023

Design and Manufacture of TPS BPM Diamond-Edge Gasket

2549

Huang, Y.T. Huang, C.-C. Chang, C.L. Chen, J.-R. Chen, G.-Y. Hsiung, H.P. Hsueh
NSRRC, Hsinchu, Taiwan

TPS vacuum chamber is oil-free machined and the material is A6061T651 which the Brinell hardness is 95 kg/mm2. Beam position monitors are installed onto the bending chambers, B1 and B2 and the straight chambers, S3 and S4. The diamond-edge gasket was chosen to seal between BPM flange (SS316L) and the vacuum chamber (A6061T651). Easily manufactured, low cost and less clamping force are three main advantages of this diamond-edge gasket. This diamond-edge gasket is made of A1050H14 which has less hardness, 32 kg/mm2 and its surface roughness is well controlled under 0.8 μm because worse surface roughness probably lead to radial leak. Considering differences of thermal expansion between stainless steel and aluminium, SS304 set screws, nuts and washers are chosen to provide axial sealing force. The sealing ability of this diamond-edge gasket is reliable through tens of bake-out experiments. It is reminded that pre-torque should be sufficient to cause plastic deformation of the diamond-edge gasket and re-torque after baking 24hr and cooling down to room temperature is also important to prevent leaks resulting from loss of torque which usually happen at 100oC.

WEPPD024

A Study of Vacuum Pressure in TPS Cells

2552

L.H. Wu, J.-R. Chen, C.M. Cheng, G.-Y. Hsiung, C.S. Huang, Huang, Y.T. Huang
NSRRC, Hsinchu, Taiwan

Recently, the type-2 and type-3 TPS cells are installed and pumped down into vacuum status. The pumping down curves of the type-2 and type-3cells, including R03, R06, R07, R10, and R11, are recorded after on-site welding and after assembling without leakage, individually. In the R03, R06, R07, R10 cells, the pumping down curve after assembling without leakage is a little higher than that after on-site welding. In those four cells, the pumping down curve after assembling all vacuum components and pumps is similar. However, in the R11 cell, it was found that the pumping down curve after assembling without leakage is almost along that of after on-site welding. The slope of pumping down curve near 1 hour in the R11 cell is -1.52, while that in the R10 cell is -1.39. It means that the vacuum pressure in the R11 cell is apparently improved. It is confirmed that the vacuum chambers are cleaned by the same process and the assembling components are similar. Besides, the photon stopper chambers are all pre-baked to 200 oC for the same time. We try to investigate the residual gas analysis (RGA) data to find the true reasons.

WEPPD039

Status of the Utility System Construction for the 3 GeV TPS Storage Ring

2597

J.-C. Chang, W.S. Chan, J.-R. Chen, Y.F. Chiu, Y.-C. Chung, K.C. Kuo, Y.-C. Lin, C.Y. Liu, I. Liu, Z.-D. Tsai, T.-S. Ueng
NSRRC, Hsinchu, Taiwan

The construction of the utility system for the 3.0 GeV Taiwan Photon Source (TPS) was started in the end of 2009. The utility building for the TPS ring will be completed in the end of 2011. The whole construction of the utility system is scheduled to be completed in the end of 2012. Total budget of this construction is about four million dollars. This utility system presented in this paper includes the electrical power, cooling water, air conditioning, compressed air and fire control systems.

WEPPD042

The Grounding System at TPS

2606

T.-S. Ueng, J.-C. Chang, J.-R. Chen, Y.-C. Lin
NSRRC, Hsinchu, Taiwan

An elaborately designed grounding system has been installed under the TPS construction site. The ground grid was installed sector by sector to comply with the building construction schedule. The ground resistance measurement of each sector was carried out right after the grid installation. The final ground resistance measurement for the whole grounding system was performed also right after its completion. The measured ground resistances of each sector were used to estimate the final TPS ground resistance, and it was compared to the final TPS ground measurement result. Also, the analysis with computer software is used to justify it. The low impedance of TPS grounding system, < 0.15 ohm, is to insure the safety of TPS personnel and instrumentation, also, to reduce the noise of electronic devices.

WEPPD045

An Application of Multi-stage Adjustable Shock Absorbers for the Girders of Storage Ring in Taiwan Photon Source

2615

C.-S. Lin, J.-R. Chen, M.L. Chen, H.C. Ho, K.H. Hsu, D.-G. Huang, C.K. Kuan, W.Y. Lai, C.J. Lin, H.M. Luo, S.Y. Perng, P.L. Sung, Y.L. Tsai, T.C. Tseng, H.S. Wang, M.H. Wu
NSRRC, Hsinchu, Taiwan
D.-Y. Chiang
NCKU, Tainan city, Taiwan

Beam stability is a major concern for the operation of the Taiwan Photon Source (TPS). One of the many factors to instability of electron beam is mechanical vibration of the accelerator components. The TPS uses steel girders to support the magnets and vacuum chambers in the storage ring. Three pedestal and six mover assemblies support the girders. Multi-stage adjustable shock absorbers are designed for passive vibration damping, and presently installed between the girders and the pedestals. Through adjusting the amount of hydraulic fluid which bypasses the damping passage between two hydraulic chambers, the desired damping coefficient of the damping absorbers can be achieved. Experimental results of modal testing presented in this paper show that the multi-stage adjustable damping absorbers under the assembly of the girders reduced the level of girder vibration.

WEPPP087

The Improvement and Test of Laser Positioning System for TPS Magnets Alignment Inspection

2915

M.L. Chen, J.-R. Chen, H.C. Ho, K.H. Hsu, W.Y. Lai, C.-S. Lin, C.J. Lin, H.C. Lin, H.M. Luo, S.Y. Perng, P.L. Sung, Y.L. Tsai, T.C. Tseng, H.S. Wang, M.H. Wu
NSRRC, Hsinchu, Taiwan

A Laser positioning system, consist of a laser, laser position sensing devices (PSD) module and two granite blocks, is developed for the alignment inspection of TPS (Taiwan Photon Source) quadrupole and sextupole magnets during installation on a girder. The PSD module is adapted on the pole center of magnet and is designed to stand for mechanical center of magnets. For high accuracy, eliminating the influence of magnets manufacturing errors between PSD module is a major work. The PSD is mounted on a precise diameter expansible jig to absorb the manufacturing errors. The real roundness of the expansible jig can keep under 3um when diameter is expanded 80um. The PSD position is adjusted and corrected in advance, and then the PSD module center can be identical to the ideal pole position of magnets on the girder within 15um. The magnet will be aligned and adjusted by laser position on PSD. This paper describes how to eliminate the measuring error caused by magnet manufacturing error and the detail of alignment inspection procedure of magnets during the installation on a girder.

WEPPP088

Auto-alignment System and CalibrationPprocedure in TPS Girder System

2918

W.Y. Lai, J.-R. Chen, M.L. Chen, H.C. Ho, K.H. Hsu, D.-G. Huang, C.K. Kuan, C.-S. Lin, C.J. Lin, H.M. Luo, S.Y. Perng, P.L. Sung, Y.L. Tsai, T.C. Tseng, H.S. Wang, M.H. Wu
NSRRC, Hsinchu, Taiwan

The TPS (Taiwan photon source) project is under construction and will be finished in the December 2012. Considering the floor’s deformation with time and frequent earthquakes at Taiwan, the survey and alignment procedure should be taken quite often. For dealing with these difficulties and improving accuracy of girder’s position, a highly accurate auto-tuning girders system was designed to accomplish the alignment tasks. There are two cells of TPS girders and varied sensor modulus set up for testing the auto-tuning system. The adjustment of the system converges to less than 6um, and the repeatability of the testing is under 10 um. For improving the accuracy of girders position, that is critical thing to make sure all the calibration of sensors modulus correctly and accurately. The calibration procedure about sensor modular and testing results is described in this paper.

THPPD059

Conductive EMI Reduction to Kicker Magnet Power Supply in NSRRC

3647

Y.-H. Liu, J.-C. Chang, C.S. Chen, H.H. Chen, J.-R. Chen
NSRRC, Hsinchu, Taiwan

The purpose of this paper is to estimate and reduce the conductive Electromagnetic Interference (EMI) from kicker magnet power supply in TLS. A LISN system was conducted to measure the EMI spectrum of kicker power supply. The EMI noise exceeded FCC standards in some frequency range especially during kicker firing. Reducing EMI level by using different EMI filters were applied. Double pi filter was more efficient than single pi filter. After using filter, the conducted EMI could diminish lower than FCC class B. The experimental results will provide useful information to future TPS pulsed magnet design.

WEPPP089

Study of the Combined Controller for Adjusting and Locking a Girder with Micrometer-level at NSRRC

2921

H.S. Wang, M.L. Chen, W.Y. Lai, S.Y. Perng, Y.L. Tsai, T.C. Tseng
NSRRC, Hsinchu, Taiwan
J.-R. Chen
NTHU, Hsinchu, Taiwan

A girder control system is proposed to quickly and precisely adjust the displacement and rotating angle of all girders in the storage ring with little manpower at the Taiwan Photon Source (TPS) project at National Synchrotron Research Center (NSRRC). In this control girder system, six motorized cam movers supporting a girder are driven on three pedestals to perform six-axis adjustments of a girder. To increase the nature frequency of a girder, the locking system is applied to promote the stiffness of a girder structure. The locking system consists of six locking mechanisms attached to three inboard pedestals and a locking controller. The study of the girder control system and the locking system control combined are achieving to the positioning with micrometre-level. This paper presents details of the study and tests of the combined controller.