Purpose Photon source has developed to the fourth generation.The requirements for beam stability and power supply output current stability have been greatly improved.In this paper,a precision acquisition system is des...Purpose Photon source has developed to the fourth generation.The requirements for beam stability and power supply output current stability have been greatly improved.In this paper,a precision acquisition system is designed for improving the stability for power supply output current.Method The acquisition system consists of two parts,the analog to digital converter(ADC)system and the temperature control system.The composition and software simulation analysis are given in this paper.Results A prototype is made and tested.The test results showed that the acquisition system has an effective resolution of 15.5 bits,signal-to-noise ratio(SNR)of 98 dB,and integral nonlinearity(INL)of 86 ppm.The internal temperature stable range is±0.06℃.Conclusions The acquisition system can fully meet the requirements of the developed photon source.展开更多
Purpose At present,the high-energy photon source(HEPS)is under construction in Beijing.HEPS has beam emittance lower than 40 pm rad.In order to ensure low beam emittance,a high-performance fast orbit feedback system(F...Purpose At present,the high-energy photon source(HEPS)is under construction in Beijing.HEPS has beam emittance lower than 40 pm rad.In order to ensure low beam emittance,a high-performance fast orbit feedback system(FOFB)is designed for fast and accurate correction of beam orbit.The FOFB needs to have the smallest adjustment step.Therefore,as the execution unit of the FOFB system,the output current resolution of the fast corrector power supply needs to be as small as possible.In FOFB systems,precise correction of beam orbit is required for fast corrector power supply with output current resolution better than 60μA.A precision digital sampling system needs to be designed to meet the high requirements of output current resolution.Method The precision operational amplifier is used to complete the scaling and sampling of signals.The precision operational amplifier is used as the front-end processing in the circuit design to complete the amplitude processing and filtering.Meanwhile,the precision operational amplifier is used as the driver of the precision analog to digital converter(ADC)chip.A precision ADC chips based on oversampling technology is used.With this scheme,the selected ADC chip can have the advantages of both high speed and high precision.A simulation prototype is built for test,and the performance parameters of key chips in the design are given.Results A precision voltage reference is used to test the designed digital sampling system.The test results showed that the acquisition system has an effective resolution of 21.6 bits.The HEPS fast corrector power supply is used for testing the developed precision sampling system.The test result showed that the output current resolution of fast corrector power supply is lower than 16μA.展开更多
Purpose This power supply prototype is developed for the quadrupole magnets in the storage ring of HEPS.The project requires a high current stability of these power supplies,in order to master the key technology of th...Purpose This power supply prototype is developed for the quadrupole magnets in the storage ring of HEPS.The project requires a high current stability of these power supplies,in order to master the key technology of this type of power supply in advance,a prototype is made in the project of HEPS test facility.Methods Modularization is used in the prototype’s topology and a combination of digital and analog control is adopted in the closed-loop control.Three control loops are used to improve the output current’s quality.In order to improve the current stability,the key devices in the circuit are under thermostatical controlled.Results The acceptance test results for the NDRC are given in details,which show that all the parameters are better than the design indexes.Conclusions After a lot of experiments and tests,all the parameters of this prototype passed the acceptance test.Among the results,the stability of this prototype achieved 5.2 ppm,the repeatability is 3.2 ppm,and the low-frequency voltage ripples are lower than the requirements of Physicists.The success of this prototype means that the requirements of power supplies in physical design can be met.展开更多
Background Fourth-generation photon sources like Free Electron Lasers(FEL)and Diffraction-Limited Storage Rings(DLSR)have high requirements for beam emittance.In the case of DLSR sources,a set of high-performance fast...Background Fourth-generation photon sources like Free Electron Lasers(FEL)and Diffraction-Limited Storage Rings(DLSR)have high requirements for beam emittance.In the case of DLSR sources,a set of high-performance fast orbit feedback system(FOFB)is needed to correct the beam orbit quickly and accurately.Purpose FOFB system has four key components,which is BPM,orbit feedback calculation,fast correction magnet and fast corrector power supply.The FOFB gives the correction command and controls the fast corrector power supply to drive the fast correction magnet to correct the beam quickly and accurately.The corrector power supply has an important impact on the performance of FOFB.The corrector power supply needs to have high bandwidth and low output current ripple.Methods The new GaN power device is used to solve the restriction of the high-speed switching.The switching frequency of the power supply is increased to 300 kHz.The control system is designed to improve the bandwidth and optimize the output current ripple.The modeling analysis of the key parts of the system is given and the simulation experiments are carried out with MATLAB.Results and conclusion The test results showed that bandwidth of the designed power supply is 20 kHz.The step response time is 18us and output current ripple is lower than 1 mA.展开更多
文摘Purpose Photon source has developed to the fourth generation.The requirements for beam stability and power supply output current stability have been greatly improved.In this paper,a precision acquisition system is designed for improving the stability for power supply output current.Method The acquisition system consists of two parts,the analog to digital converter(ADC)system and the temperature control system.The composition and software simulation analysis are given in this paper.Results A prototype is made and tested.The test results showed that the acquisition system has an effective resolution of 15.5 bits,signal-to-noise ratio(SNR)of 98 dB,and integral nonlinearity(INL)of 86 ppm.The internal temperature stable range is±0.06℃.Conclusions The acquisition system can fully meet the requirements of the developed photon source.
文摘Purpose At present,the high-energy photon source(HEPS)is under construction in Beijing.HEPS has beam emittance lower than 40 pm rad.In order to ensure low beam emittance,a high-performance fast orbit feedback system(FOFB)is designed for fast and accurate correction of beam orbit.The FOFB needs to have the smallest adjustment step.Therefore,as the execution unit of the FOFB system,the output current resolution of the fast corrector power supply needs to be as small as possible.In FOFB systems,precise correction of beam orbit is required for fast corrector power supply with output current resolution better than 60μA.A precision digital sampling system needs to be designed to meet the high requirements of output current resolution.Method The precision operational amplifier is used to complete the scaling and sampling of signals.The precision operational amplifier is used as the front-end processing in the circuit design to complete the amplitude processing and filtering.Meanwhile,the precision operational amplifier is used as the driver of the precision analog to digital converter(ADC)chip.A precision ADC chips based on oversampling technology is used.With this scheme,the selected ADC chip can have the advantages of both high speed and high precision.A simulation prototype is built for test,and the performance parameters of key chips in the design are given.Results A precision voltage reference is used to test the designed digital sampling system.The test results showed that the acquisition system has an effective resolution of 21.6 bits.The HEPS fast corrector power supply is used for testing the developed precision sampling system.The test result showed that the output current resolution of fast corrector power supply is lower than 16μA.
文摘Purpose This power supply prototype is developed for the quadrupole magnets in the storage ring of HEPS.The project requires a high current stability of these power supplies,in order to master the key technology of this type of power supply in advance,a prototype is made in the project of HEPS test facility.Methods Modularization is used in the prototype’s topology and a combination of digital and analog control is adopted in the closed-loop control.Three control loops are used to improve the output current’s quality.In order to improve the current stability,the key devices in the circuit are under thermostatical controlled.Results The acceptance test results for the NDRC are given in details,which show that all the parameters are better than the design indexes.Conclusions After a lot of experiments and tests,all the parameters of this prototype passed the acceptance test.Among the results,the stability of this prototype achieved 5.2 ppm,the repeatability is 3.2 ppm,and the low-frequency voltage ripples are lower than the requirements of Physicists.The success of this prototype means that the requirements of power supplies in physical design can be met.
文摘Background Fourth-generation photon sources like Free Electron Lasers(FEL)and Diffraction-Limited Storage Rings(DLSR)have high requirements for beam emittance.In the case of DLSR sources,a set of high-performance fast orbit feedback system(FOFB)is needed to correct the beam orbit quickly and accurately.Purpose FOFB system has four key components,which is BPM,orbit feedback calculation,fast correction magnet and fast corrector power supply.The FOFB gives the correction command and controls the fast corrector power supply to drive the fast correction magnet to correct the beam quickly and accurately.The corrector power supply has an important impact on the performance of FOFB.The corrector power supply needs to have high bandwidth and low output current ripple.Methods The new GaN power device is used to solve the restriction of the high-speed switching.The switching frequency of the power supply is increased to 300 kHz.The control system is designed to improve the bandwidth and optimize the output current ripple.The modeling analysis of the key parts of the system is given and the simulation experiments are carried out with MATLAB.Results and conclusion The test results showed that bandwidth of the designed power supply is 20 kHz.The step response time is 18us and output current ripple is lower than 1 mA.
