Design And Verification Prototype Of Timing System For HIAF

High Intensity heavy-ion Accelerator Facility(HIAF)is a heavy ion scientific research facility with an internationally leading level and a wide range of uses.It adopts accelerator cascade to achieve high power and high current intensity.To achieve coordination between devices,the operation of cascade requires high-precision timing scheduling.High-precision timing is the key to precise control of the equipment,which determines the accuracy and precision of the operation of the equipment.The facility is distributed within a range of 1km,and the number of devices need to be controlled more than 600,and the accuracy is better than 2ns.At the same time,for the construction of the BEIF,the designed system needs to have a larger range of equipment coverage and precision improvement space,which makes challenges for the realization of timing scheduling.Timing system is a system-level solution to realize timing scheduling of HIAF,the standard protocol is used to enhance the scalability for the system.As the accuracy is better than 2ns and the precision is sub-nanosecond,the injection,capture,acceleration and extraction efficiency are improved and the parallel beam supply mode of the device is optimized.At the system level,this dissertation designs an absolute timing system,which has significance for the design of similar systems and timing optimization.Based on the White Rabbit protocol,this dissertation designs the synchronization scheme,which realizes the synchronization of large-span,multi-node,real-time calibration,and solves the problems such as the reduction of precision caused by long-distance transmission,the change of network structure by multi-nodes,and the real-time calibration.In terms of system reliability,this dissertation uses network technology to the design.By analyzing the reliability of the network topology,studying the influence of the network topology on synchronization and data transmission,the basic network redundancy scheme is obtained.By focusing on the analysis of the reliability of data transmission in the network,studying the reliable transmission of data under different parameters,and providing data redundancy schemes and parameters suitable for system,the reliability of data transmission is improved.The network bandwidth occupied by different data is analyzed,and the transmission time of control information in the network is emphatically studied.The priority of data transmission and the data transmission scheme of dividing VLAN are obtained.Through investigating the network monitoring solution,and choosing Zabbix and Grafana software to achieve real-time monitoring of the entire system,the reliable of the entire system is improved.This dissertation realizes the transmission of information for synchronization,control,configuration and alarm on one fiber for the first time in China.Based on the modular design,the synchronization information and other information are separated,and the scheme requires the configuration and status monitoring of the node through the data network is optimized.Based on the high-precision delay circuits and time-to-digital converters,a scheme for constructing a delay chain to achieve sub-nanosecond delay output and timestamping is obtained,and the adjustment step and timestamp accuracy are increased to about 400 picoseconds.In terms of interfaces,the unified abstract modeling of the interfaces of different devices is carried out,and the design scheme of the hardware interface is optimized,which effectively solves the problem that different devices are difficult to access the system.This dissertation is oriented by project requirements,and the system architecture was designed.The software and hardware modules of the data master,clock master,network and terminal node are designed and implemented.Relying on the prototype of the timing system,a system-level test platform is built to realize the whole system test.The accuracy is better than 1ns,the precision is better than 60 ps,and the external reference trigger output deviation is less than 300 ps,which meets the requirements of the timing system of HIAF and has a certain performance improvement space.