分布式结构作为常用的远程通信架构,其通过多个独立的局部控制子系统将回路的数据进行集中获取、集中管理和集中控制.电力线作为连接子系统间的通信介质,传输数据时接受和发送方共用同一信道,导致终端并发数据相互干扰而使数据错乱.通过引入CSMA/CA机制,提出了一种解决数据并发错乱的电力载波通信技术,提高了通信的稳定性和可靠性.分析了基于CSMA/CA的电力载波通信技术,建立了在并发条件下电力线上多终端正确发送数据所需时间即延迟时间的计算模型,并运用蒙特卡洛法仿真求出延迟时间的数学期望.在工程实验中验证了这种技术的可行性,对影响延迟时间的因素进行灵敏度分析,结果可以为智能照明系统设计提供理论与实践依据.
Distributed control system focuses on the data acquisition, centralized management and centralized control of the circuit through independent multi-subsystem. Receiver and transmitter of power line share the same communication channel when message is transferred by terminals, which will give rise to data disorder. An anti-collision PLC technology based on CSMA/CA mechanism was proposed to solve the shortcoming,by which the stability and reliability of the communication could be improved. After analyzing the principle of data collision, the calculation model of the time which was used to transmit message between terminals simultaneously was established. Monte Carlo method was presented to compute the expectation of delay time. The feasibility of this technique was verified in engineering experiments. Sensitivity analysis was made to verify the factors that affect the delay time. The results provide a theoretical and practical basis of the design of intelligent lighting system.