Abstract: To solve load balancing problem of Power Line Communication (PLC) network in Smart Grid (SG), an adaptive opportunistic routing protocol named LBORP (Load Balancing Opportunistic Routing Protocol) was proposed. All the candidate forwarding nodes receiving a packet in LBORP had the opportunity to participate in packet forwarding. As a result, packet forwarding was no longer limited to one routing path, which avoided load imbalance caused by traffic with only one link for traffic to pass. And forwarding priority of the candidate forwarding nodes considered not only the distance from forwarding nodes to destination node, but also instability of PLC links and change of traffic. Besides, an implicit acknowledgment scheme was adopted in LBORP, further reducing the end-to-end delay of the proposed protocol. In simulation experiment, compared to PLC-TR (Power Line Communication-Tree Routing) and PLC-OR (Power Line Communication-Opportunistic Routing), LBORP reduced delay by 19.7% and 45.8% respectively and reduced packet loss rate by 23.4% and 32.5% respectively. Experimental results show that LBORP can achieve network load balancing, improve network reliability and reduce end-to-end delay.

Key words: Smart Grid (SG), Power Line Communication (PLC), load balancing, routing algorithm, opportunistic routing

摘要： 针对智能电网（SG）中电力线通信（PLC）网络中负载均衡的问题，提出了一个自适应机会路由协议——负载均衡的机会路由协议（LBORP）。在LBORP中，所有收到数据包的候选转发节点都有机会参与到数据包的转发中，不再局限于一条路由路径，避免了流量仅从一条链路经过导致的负载不均衡现象；而且候选转发节点的转发优先级不仅考虑到转发节点到目的节点的距离，还考虑到了PLC链路的不稳定性以及流量的变化。除此之外，在LBORP中采用一种隐式确认方案，进一步减少协议的端到端时延。在仿真实验中，与基于有序树的PLC路由协议（PLC-TR）和PLC机会路由协议（PLC-OR）相比，LBORP在时延上分别降低了19.7%和45.8%，在丢包率上分别降低了23.4%和32.5%。实验结果表明，LBORP能够实现网络的负载均衡，提升网络的可靠性并减小端到端时延。

关键词: 智能电网, 电力线通信, 负载均衡, 路由算法, 机会路由