构网型储能设备(grid-forming energy storage system,GFM-ESS)因具备主动构网和提供惯量支持等能力,已成为解决大规模新能源接入引发宽频振荡问题的重要手段。然而,GFM-ESS的容量配置直接影响系统投资成本,在保障系统稳定性的前提下如...构网型储能设备(grid-forming energy storage system,GFM-ESS)因具备主动构网和提供惯量支持等能力,已成为解决大规模新能源接入引发宽频振荡问题的重要手段。然而,GFM-ESS的容量配置直接影响系统投资成本,在保障系统稳定性的前提下如何实现其经济性配置,成为当前研究热点。现有研究多侧重于提升系统稳定裕度,较少考虑GFM-ESS容量与选址的协同优化,且缺乏统一的量化指标指导配置方案的制定。为此,本工作基于s域模态分析理论,构建了一条集模态识别、关键节点筛选与容量协同优化于一体的完整技术链条,并提出一种考虑经济性约束的GFM-ESS容量与选址协同优化方法。首先,通过归一化模态参与因子对各母线的振荡模态贡献进行定量评估,识别影响不稳定模态的关键节点;针对系统多模态振荡特性,引入粒子群优化(particle swarm optimization,PSO)算法,在预选节点上对储能容量进行协同优化,以满足预设的稳定裕度指标。仿真结果表明,所提技术链能够有效识别关键控制节点,并以较小的GFM-ESS投入容量将原本不稳定的系统恢复至稳定状态,且具备明确的稳定裕度,为新型电力系统中GFM-ESS的合理配置提供了理论支撑。展开更多
针对单一监测信号难以实现电主轴复杂工况的精确评估问题,提出了一种基于熵权法改进D-S证据理论的分析方法。基于电主轴不同类型的监测信号,结合多域特征提取、主成分分析(Principal Component Analysis,PCA)算法和改进基于密度的噪声...针对单一监测信号难以实现电主轴复杂工况的精确评估问题,提出了一种基于熵权法改进D-S证据理论的分析方法。基于电主轴不同类型的监测信号,结合多域特征提取、主成分分析(Principal Component Analysis,PCA)算法和改进基于密度的噪声应用空间聚类(Density-Based Spatial Clustering of Applications with Noise,DBSCAN)算法,获取能够表征电主轴运行状态的特征指标。引入信度熵概念,基于熵权法对经典D-S证据理论算法进行改进,降低不敏感信号的干扰,改善了电主轴弱状态信息特征的融合效果。设计并搭建了电主轴试验台,对比研究了电主轴在不同转速下服役状态评估效果。依托现有的集成开发环境(Integrated Development Environment,IDE)开发了主轴运维信息管理评估系统,实现了电主轴服役过程中的数据采集、健康监测、状态评估的应用,满足了高精密电主轴运行维护的工程需求。为机床或电主轴等生产企业和设备制造企业提供系统的状态诊断与运维管理的系统解决方案。展开更多
A complete closed-loop third order s-domain model is analyzed for a frequency synthesizer. Based on the model and root-locus technique, the procedure for parameters design is described, and the relationship between th...A complete closed-loop third order s-domain model is analyzed for a frequency synthesizer. Based on the model and root-locus technique, the procedure for parameters design is described, and the relationship between the process,voltage,and temperature variation of parameters and the loop stability is quantitatively analyzed. A variation margin is proposed for stability compensation. Furthermore,a simple adjustable current cell in the charge pump is proposed for additional stability compensation and a novel VCO with linear gain is adopted to limit the total variation. A fully integrated frequency synthesizer from 1 to 1.05GHz with 250kHz channel resolution is implemented to verify the methods.展开更多
文摘针对单一监测信号难以实现电主轴复杂工况的精确评估问题,提出了一种基于熵权法改进D-S证据理论的分析方法。基于电主轴不同类型的监测信号,结合多域特征提取、主成分分析(Principal Component Analysis,PCA)算法和改进基于密度的噪声应用空间聚类(Density-Based Spatial Clustering of Applications with Noise,DBSCAN)算法,获取能够表征电主轴运行状态的特征指标。引入信度熵概念,基于熵权法对经典D-S证据理论算法进行改进,降低不敏感信号的干扰,改善了电主轴弱状态信息特征的融合效果。设计并搭建了电主轴试验台,对比研究了电主轴在不同转速下服役状态评估效果。依托现有的集成开发环境(Integrated Development Environment,IDE)开发了主轴运维信息管理评估系统,实现了电主轴服役过程中的数据采集、健康监测、状态评估的应用,满足了高精密电主轴运行维护的工程需求。为机床或电主轴等生产企业和设备制造企业提供系统的状态诊断与运维管理的系统解决方案。
文摘A complete closed-loop third order s-domain model is analyzed for a frequency synthesizer. Based on the model and root-locus technique, the procedure for parameters design is described, and the relationship between the process,voltage,and temperature variation of parameters and the loop stability is quantitatively analyzed. A variation margin is proposed for stability compensation. Furthermore,a simple adjustable current cell in the charge pump is proposed for additional stability compensation and a novel VCO with linear gain is adopted to limit the total variation. A fully integrated frequency synthesizer from 1 to 1.05GHz with 250kHz channel resolution is implemented to verify the methods.
