Research On Congestion Control Algorithm Of Wireless Communication Network For Smart Distribution Grid

The timely accurate interaction of distribution information is very important for the normal operation of the smart distribution grid,and the wireless communication technology is widely used in the access layer of distribution communication network because of its large coverage,low construction cost and convenient maintenance.However,the sharp increase of distribution business in the distribution wireless communication network and the limited network resources of the access layer make the congestion of this network extremely severe,reducing the service quality of the distribution business.Therefore,on the basis of congestion prevention and congestion avoidance,the congestion control algorithm for smart distribution wireless communication network is studied in this paper.This algorithm can effectively reduce packet loss rate and transmission delay of the distribution information,so as to improve the operation reliability of smart distribution grid.In view of this,focusing on the congestion control of the smart distribution wireless communication network,the application of the active queue management algorithm which can prevent congestion and queue scheduling algorithm with the function of congestion avoidance in the smart distribution wireless communication network is studied.The special studies are as follows:(1)According to the analysis of distribution communication network architecture and the demand of distribution business,the business priority is divided.Meanwhile,the cause of the network congestion and the basic ideas of congestion control are expounded as well as the algorithms of queue management and queue scheduling are researched.Furthermore,a suitable solution for congestion control of distribution wireless communication network is put forward.(2)Aiming at the problem that packet loss rate and the transmission delay are difficult to meet the demand of business in distribution wireless communication network when the business increase sharply,the RED algorithm was improved by introducing distribution business priorities.After considering buffer capacity and the impact on the size of the buffer capacity by lost packets of distribution business,the algorithm that forecast buffer queue size can be adjustable called Estimate and Buffer Size Adjustment RED is proposed.The simulation results shows that when congestion occurs in the distribution business queue,the proposed algorithm can guarantee the quality of distribution business with high priority,reduce the packet loss rate of distribution business and improve the buffer utilization of resources.(3)For the serious shortage of queue buffer capacity which is caused by excessive sharp increment of distribution business in the distribution wireless communication network,a buffer queue scheduling algorithm based on the priority of the distribution business in collaboration with the queue management algorithm is proposed to solve this problem.In this algorithm,the weights of buffer queue are calculated and adjusted according to the buffer capacity of current distribution business queue.Then,the output rate of this distribution business packet will be adjusted correspondingly.The simulation results show that the proposed algorithm can meet the delay demand of high-priority distribution business and make distribution wireless communication network have good stability when a large number of distribution business burst.In conclusion,the proposed two algorithms can reduce the packet loss rate of the distribution business,improve the utilization rate of cache resource,meet the delay requirements of business and moreover control the congestion of the smart distribution wireless communication network effectively through the queue management and scheduling of the distribution business.