In this paper,a model free volt/var control(VVC)algorithm is developed by using deep reinforcement learning(DRL).We transform the VVC problem of distribution networks into the network framework of PPO algorithm,in ord...In this paper,a model free volt/var control(VVC)algorithm is developed by using deep reinforcement learning(DRL).We transform the VVC problem of distribution networks into the network framework of PPO algorithm,in order to avoid directly solving a large-scale nonlinear optimization problem.We select photovoltaic inverters as agents to adjust system voltage in a distribution network,taking the reactive power output of inverters as action variables.An appropriate reward function is designed to guide the interaction between photovoltaic inverters and the distribution network environment.OPENDSS is used to output system node voltage and network loss.This method realizes the goal of optimal VVC in distribution network.The IEEE 13-bus three phase unbalanced distribution system is used to verify the effectiveness of the proposed algorithm.Simulation results demonstrate that the proposed method has excellent performance in voltage and reactive power regulation of a distribution network.展开更多
VoLTE 是一种基于 4G IMS 的语音服务,使得数据和语音服务能够在都在 4G IP 网络上承载。它采用高效率编解码技术,与 2G 和 3G 语音通话相比,VoLTE 可以将语音质量提高约 40%。MOS是作为 VoLTE 语音质量评估的重要指标,本文通过对丢包...VoLTE 是一种基于 4G IMS 的语音服务,使得数据和语音服务能够在都在 4G IP 网络上承载。它采用高效率编解码技术,与 2G 和 3G 语音通话相比,VoLTE 可以将语音质量提高约 40%。MOS是作为 VoLTE 语音质量评估的重要指标,本文通过对丢包率、时延、包抖动与 MOS 值的相关性以及造成这些问题的无线因素开展量化研究,明确影响 VoLTE MoS 质量的原因,并针对性提出了提升MOS 的方法,为后续 VoLTE MOS 提升提供参考借鉴。展开更多
在LTE网络大规模部署的现阶段,4G用户规模和业务量持续攀高,4G手机渗透率迅速提升,而语音业务作为运营商重要的收入来源,其重要性不言而喻。针对LTE的语音终极实现方案VoLTE(Voice over LTE),研究了实现VoLTE的关键技术,分析了影响语音...在LTE网络大规模部署的现阶段,4G用户规模和业务量持续攀高,4G手机渗透率迅速提升,而语音业务作为运营商重要的收入来源,其重要性不言而喻。针对LTE的语音终极实现方案VoLTE(Voice over LTE),研究了实现VoLTE的关键技术,分析了影响语音质量的多种因素,提出了一种基于E-model的VoLTE语音性能评估方法,在LTE网络率先部署的密集城区场景中,基于不同网络配置和并发用户数,对VoLTE业务性能进行仿真,并采用E模型进行语音质量分析,最终实现对VoLTE的语音性能评估。展开更多
基金supported by the Science and Technology Project of State Grid Zhejiang Electric Power Co.,Ltd.under Grant B311JY21000A。
文摘In this paper,a model free volt/var control(VVC)algorithm is developed by using deep reinforcement learning(DRL).We transform the VVC problem of distribution networks into the network framework of PPO algorithm,in order to avoid directly solving a large-scale nonlinear optimization problem.We select photovoltaic inverters as agents to adjust system voltage in a distribution network,taking the reactive power output of inverters as action variables.An appropriate reward function is designed to guide the interaction between photovoltaic inverters and the distribution network environment.OPENDSS is used to output system node voltage and network loss.This method realizes the goal of optimal VVC in distribution network.The IEEE 13-bus three phase unbalanced distribution system is used to verify the effectiveness of the proposed algorithm.Simulation results demonstrate that the proposed method has excellent performance in voltage and reactive power regulation of a distribution network.
文摘VoLTE 是一种基于 4G IMS 的语音服务,使得数据和语音服务能够在都在 4G IP 网络上承载。它采用高效率编解码技术,与 2G 和 3G 语音通话相比,VoLTE 可以将语音质量提高约 40%。MOS是作为 VoLTE 语音质量评估的重要指标,本文通过对丢包率、时延、包抖动与 MOS 值的相关性以及造成这些问题的无线因素开展量化研究,明确影响 VoLTE MoS 质量的原因,并针对性提出了提升MOS 的方法,为后续 VoLTE MOS 提升提供参考借鉴。
文摘在LTE网络大规模部署的现阶段,4G用户规模和业务量持续攀高,4G手机渗透率迅速提升,而语音业务作为运营商重要的收入来源,其重要性不言而喻。针对LTE的语音终极实现方案VoLTE(Voice over LTE),研究了实现VoLTE的关键技术,分析了影响语音质量的多种因素,提出了一种基于E-model的VoLTE语音性能评估方法,在LTE网络率先部署的密集城区场景中,基于不同网络配置和并发用户数,对VoLTE业务性能进行仿真,并采用E模型进行语音质量分析,最终实现对VoLTE的语音性能评估。
