Accurate electric energy(EE)measurements and billing estimations in a power system necessitate the development of an energy flow distribution model.This paper summarizes the results of investigations on a new problem ...Accurate electric energy(EE)measurements and billing estimations in a power system necessitate the development of an energy flow distribution model.This paper summarizes the results of investigations on a new problem related to the determination of EE flow in a power system over time intervals ranging from minutes to years.The problem is referred to as the energy flow problem(EFP).Generally,the grid state and topology may fluctuate over time.An attempt to use instantaneous(not integral)power values obtained from telemetry to solve classical electrical engineering equations leads to significant modeling errors,particularly with topology changes.A promoted EFP model may be suitable in the presence of such topological and state changes.Herein,EE flows are determined using state estimation approaches based on direct EE measurement data in Watt-hours(Volt-ampere reactive-hours)provided by electricity meters.The EFP solution is essential for a broad set of applications,including meter data validation,zero unbalance EE billing,and nontechnical EE loss check.展开更多
文摘为减少电力线信道时变性对自动抄表系统(automaticmeter-reading system,AMRS)计量数据传输效率的不利影响,提出了中继路由与分组队列相结合的方法。中继路由将整条通信链路分割成若干子链路,可以有效提高传输效率,但传输效率仍受制于信噪比(signal to noise ratio,SNR)最低的子链路。为充分利用每条子链路的最大传输效率,在中继路由的基础上,引入了分组队列机制。该方法根据接收和发送子链路的信道状况,动态调整分组队列长度,实现了发送子链路和接收子链路独立传输。由基于SNR的3状态Markov信道模型得到分组的平均发送次数,以该次数表示中继路由的分组接收速率和分组发送速率,建立了基于OPNET的M/M/1/K的AMRS分组排队模型。通过分析不同排队强度时的分组队列长度与队列延时等参数,验证了该方法能够提高传输效率。
文摘Accurate electric energy(EE)measurements and billing estimations in a power system necessitate the development of an energy flow distribution model.This paper summarizes the results of investigations on a new problem related to the determination of EE flow in a power system over time intervals ranging from minutes to years.The problem is referred to as the energy flow problem(EFP).Generally,the grid state and topology may fluctuate over time.An attempt to use instantaneous(not integral)power values obtained from telemetry to solve classical electrical engineering equations leads to significant modeling errors,particularly with topology changes.A promoted EFP model may be suitable in the presence of such topological and state changes.Herein,EE flows are determined using state estimation approaches based on direct EE measurement data in Watt-hours(Volt-ampere reactive-hours)provided by electricity meters.The EFP solution is essential for a broad set of applications,including meter data validation,zero unbalance EE billing,and nontechnical EE loss check.
