为保证电力系统信息综合传输中各种信息业务的服务质量,提出一种改进的最坏情况下公平的加权公平队列(improved worst-case fair weighted fair queueing plus,IWF2Q)调度算法。该算法通过在WF2Q算法的虚拟开始时间和虚拟完成时间计算公式中引入"虚拟延迟时间",解决了电力系统信息综合传输中由WF2Q算法导致的推迟传输高优先级信息业务分组的问题。以NS2为工具,建立了基于区分服务体系结构模型的IEEE 14母线系统信息综合传输网络仿真模型,运用网络仿真方法定量评估了以IWF2Q算法实现基于区分服务体系结构模型的电力系统信息综合传输时各类信息业务的实时性和公平性。仿真结果表明,IWF2Q算法降低了高优先级信息业务分组延时,同时兼顾综合传输的各类信息业务间的公平性,证明了IWF2Q算法的有效性和可行性。
To guarantee the quality of service (QoS) of various wide area communication services for integrated information transmission in power systems, an improved worst-case fair weighted fair queueing plus (IWF2Q+) scheduling algorithm was proposed. IWF2Q+ scheduling algorithm was obtained by introducing virtual delay time in the formulas of virtual start time and virtual finish time of WF2Q+ scheduling algorithm. The problem that the packets of high-priority communication services were delayed by WF2Q+ scheduling algorithm was solved by IWF2Q+ scheduling algorithm. The integrated information transmission network model on IEEE 14-bus test system was constructed in NS2 based on the Differentiated Services (Diffserv) architectural model which was implemented by IWF2Q+ scheduling algorithm. Real-time performance and fairness of the communication services in integrated information transmission had been verified by a network simulation. The simulation result shows that IWF2Q+ scheduling algorithm is valid and feasible as the packet delay of high-priority communication services is reduced and the fairness of the traffics is considered.