Hefei Light Source Synchronous Optical Position Measuring System Developed And Applied Research

This thesis treats the development of photon beam position monitor system in HLS (Hefei Light Source), including SR characteristics computing of bend magnet, design of two-wire monitor with the spring system, hardware design, software design and the performance of PBPM system in HLS. Design of the vacuum monitor and control system of diagnostics beamline at HLS is also introduced in this thesis.Accurate and reliable photon beam position monitor system is essential for the successful operation of synchrotron radiation source beamlines. Log-ratio method is first presented in this thesis. Two methods of position signal processing are given and compared. Log-ratio method has a higher dyamatic range, wider linearity range and larger sensitivity than A/E method. A new wire photon beam position monitor with the spring system was designed and installed in the machine diagnostic beamline (MDBL) at HLS. The monitor was tested and calibrated; the results are fit well with the computed results.A photon beam position monitor system with the log-ratio method was designed. The current to voltage converter, signal conditioning, 16bits analog to digital converter, MCU and the enthernet controller were interated into one board, which has a good performance rice ratio. The current to voltage converter is the key technique of the system, and a logarithmic and log-ratio amplifier (L0G112) is used for I/V converting to detect wide input currents. The new designed system can measure 5 decades input currents; the linearity range is about 4mm, and the resolution is less 2μm.The results of the applications of the new designed system are given. Orbit stability was measured and compared with the BPM. SR vertical size was measured with the new designed monitor in two methods, and the results fit well. The beam current has a less affect on the SR vertical size. S/N and linearity can be improved with a positive bias voltage applied to the copper block, but sensitivity will be decreased. The system is proved reliable and able to provide accurate and continuous data on the photon beam position.The vacuum monitor and control system of the diagnostic beamline is also introduced. The front end of the diagnostic beamline was introduced. Both software and hardware were designed. The high stability has been realized with the applications of the CPLD & RF card, and the system has a friendly operation interface due to the use of Human-Machine Interface (HMI).