本文選題：實時以太網(wǎng) + 時間同步�。� 參考：《中國科學院研究生院（上海應用物理研究所）》2014年碩士論文

【摘要】：在上海光源裝置、質子治療裝置等大型加速器系統(tǒng)的控制中，存在由多個控制器組成的分布式系統(tǒng)實現(xiàn)高速實時控制的需求，如上海光源的機器快聯(lián)鎖保護系統(tǒng)，其時間響應需求為1ms，其IO信號圍繞432米周長的儲存環(huán)分布于20個單元中。 課題采用基于實時以太網(wǎng)的解決方案。為了實現(xiàn)課題目標，課題研究在1ms的時間內完成100個IO站點之間的實時通信的方法，設計按照時間分片原理進行實時數(shù)據(jù)的傳輸，并指出實現(xiàn)時間同步是實現(xiàn)實時以太網(wǎng)的關鍵，同時分析比較了現(xiàn)有的時間同步協(xié)議，最終本課題采用IEEE1588精準時間同步協(xié)議實現(xiàn)所有站點的時間同步。 論文首先介紹了IEEE1588精準時間同步協(xié)議的相關理論知識，包括IEEE15-88時間同步的基本原理和IEEE1588協(xié)議的時鐘類型，并分析了IEEE1588硬件時間戳的標記、影響時間同步的各種因素和實現(xiàn)IEEE1588的各種方案。其次，課題采用FPGA和千兆以太網(wǎng)實現(xiàn)IEEE1588時間同步和實時以太網(wǎng)，并根據(jù)需求定制了IO板，完成了分布式IO系統(tǒng)的基礎硬件框架。最后，課題在FPGA平臺上編寫VHDL硬件語言程序完成IEEE1588時間同步和實時以太網(wǎng)的相關模塊設計，并且針對普通晶振的頻率偏差造成IEEE1588同步精度低的問題，，本文提出了一種頻率動態(tài)補償?shù)乃惴ǎ怪鲿r鐘和從時鐘實現(xiàn)更高的時間同步精度。 課題采用兩種測試方案進行IEEE1588時間同步的測試。采用IEEE1588時間同步測試方案一驗證了頻率動態(tài)補償算法的可行性，極大地提高了時間同步的精度；采用IEEE1588測試方案二分別測試了在不同同步周期以及在特定同步周期條件下采用不同的連接方式時的時間同步精度，并分析了交換機的延遲抖動和同步周期對時間同步精度的影響。由于上海光源的網(wǎng)絡系統(tǒng)的延遲抖動比較大，在上海光源的網(wǎng)絡拓撲結構中測試的IEEE1588的時間同步結果無法滿足需求，也就無法在現(xiàn)有的上海光源的網(wǎng)絡拓撲結構中實現(xiàn)本文設計的實時以太網(wǎng)。但在實驗室條件下，本文設計的實時以太網(wǎng)的測試得到了相對比較滿意的結果。 論文的最后，對整個論文進行了總結，并針對上海光源的網(wǎng)絡系統(tǒng)的延遲抖動大造成無法實現(xiàn)高精度的時間同步的問題，本文提出了新的網(wǎng)絡拓撲結構進行實時以太網(wǎng)的設計。
[Abstract]:In the control of large accelerator systems such as the Shanghai light source device and the proton therapy device, there is a need for high speed real-time control in a distributed system composed of multiple controllers, such as the machine fast interlocking protection system of the Shanghai light source, whose time response demand is 1ms, and its IO signal is distributed around the 20 units around the 432 meter circumference.
The project uses real-time Ethernet based solutions. In order to achieve the goal of the project, the task is to complete the real-time communication between 100 IO sites in the time of 1ms, design the real-time data transmission according to the time fragmentation principle, and point out that time synchronization is the key to realize real-time Ethernet. At the same time, the analysis and comparison are made. Some time synchronization protocols. Finally, this topic uses IEEE1588 precise time synchronization protocol to achieve the time synchronization of all sites.
The thesis first introduces the relevant theoretical knowledge of IEEE1588 precise time synchronization protocol, including the basic principle of IEEE15-88 time synchronization and the clock type of the IEEE1588 protocol, and analyzes the tags of the IEEE1588 hardware timestamp, the various factors that affect the time synchronization and the various schemes to realize the IEEE1588. Secondly, the topic uses FPGA and Gigabit Ethernet. The network implements IEEE1588 time synchronization and real-time Ethernet, and customize the IO board according to the requirement, complete the basic hardware framework of the distributed IO system. Finally, the task is to write the VHDL hardware language program on the FPGA platform to complete the related module design of the IEEE1588 time synchronization and the real-time Ethernet, and to cause the IEEE1 in the frequency deviation of the ordinary crystal oscillator. 588 the problem of low synchronization accuracy is presented in this paper. A frequency dynamic compensation algorithm is proposed to achieve higher time synchronization accuracy between the master clock and the clock.
Two kinds of test schemes are used to test the time synchronization of IEEE1588. The feasibility of the frequency dynamic compensation algorithm is verified by the IEEE1588 time synchronization test scheme, and the time synchronization accuracy is greatly improved. The IEEE1588 test scheme two is used to test the different same step period and the specific synchronization period. The time synchronization precision of different connection modes is used, and the effect of delay jitter and synchronization period on the time synchronization precision is analyzed. Because the delay jitter of the network system of the Shanghai light source is larger, the time synchronization results of the IEEE1588 which are tested in the network topology of the Shanghai light source can not meet the demand, and it is impossible. The real time Ethernet designed in this paper is implemented in the existing network topology of the Shanghai light source. But under the laboratory conditions, the test of real-time Ethernet designed in this paper has been relatively satisfactory.
At the end of this paper, the whole paper is summarized, and the problem that the delay jitter of the network system of Shanghai light source can not be realized with high precision time synchronization. This paper proposes a new network topology for real-time Ethernet design.

【學位授予單位】：中國科學院研究生院（上海應用物理研究所）
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TP393.11

【參考文獻】

相關期刊論文 前3條

1 舒邦久;姚沛;劉興文;;IEEE 1588的時鐘設備模型研究[J];電子技術;2009年12期

2 桂本p

本文編號：1811408