区分配电网中发生的单相接地故障类型,能够有针对性地制定故障检修策略,提升故障处置效率。配电自动化设备作为配电网故障快速辨识与处理的重要载体,对故障分类的原理及效果差异性较大,准确率无法满足电力系统工作需求,为此提出一种基...区分配电网中发生的单相接地故障类型,能够有针对性地制定故障检修策略,提升故障处置效率。配电自动化设备作为配电网故障快速辨识与处理的重要载体,对故障分类的原理及效果差异性较大,准确率无法满足电力系统工作需求,为此提出一种基于分类回归树与多核残差网络(classfication and regression tree and multi-core ResNet, CART-MRN)的树状结构故障类型识别方法。首先,建立树状故障分类结构,利用Fourier变换、经验模态分解(empirical mode decompsition, EMD)分解等方法提取故障点电压电流的多域故障特征;其次,结合特征分析与信息增益建立适应不同小电流接地系统的融合算法模型,并引入粒子群算法优化网络超参数;最后,通过现场录波数据验证与对比实验,证明该方法能快速、有效地完成单相接地故障分类识别,且更具有适应性。展开更多
In this article,the Non-Aqueous Phase Liquid（NAPL）transport in the single filled fracture was studied with the Shan-Chen multi-component multiphase Lattice Boltzmann Method（LBM）with special consideration of wettab...In this article,the Non-Aqueous Phase Liquid（NAPL）transport in the single filled fracture was studied with the Shan-Chen multi-component multiphase Lattice Boltzmann Method（LBM）with special consideration of wettability effects.With the help of the model,the contact angle of the non-wetting phase and wetting phase interface at a solid wall could be adjusted.By considering a set of appropriate boundary conditions,the fractured conductivity was investigated in condition that the NAPL blocks the channels in the single filled fracture.In order to study the wettability effects on the NAPL transport,a constant driving force was introduced in the Shan-Chen multi-component multiphase LBM.Flow regimes with different wettabilities were discussed.Simulated results show that the LBM is a very instrumental method for simulating and studying the immiscible multiphase flow problems in single filled fracture.展开更多
配电变压器无触点有载调压技术对稳定电压具有重大意义。有载调压控制系统的耐压问题是限制无触点有载自动调压配电变压器工程应用的关键因素,上电时无触点配电变压器的自启动是另一难点。为解决这2方面的问题,文中设计出一种配电变压...配电变压器无触点有载调压技术对稳定电压具有重大意义。有载调压控制系统的耐压问题是限制无触点有载自动调压配电变压器工程应用的关键因素,上电时无触点配电变压器的自启动是另一难点。为解决这2方面的问题,文中设计出一种配电变压器无触点有载自动调压的新方案,其控制系统的电源和测量电压均取自高压(10 k V)分接头,解决分接开关与控制系统的耐压问题;分接开关和控制系统采用悬浮地技术解决对地耐压问题;采用无源自取能触发方式,并利用一组有载调压分接开关在配电变压器上电时实现自启动。模拟实验、理论分析以及近一年的运行试验考核表明,该方案可较好地解决耐压问题,且启动可靠,稳压效果平稳,具有实际应用价值。展开更多
文摘区分配电网中发生的单相接地故障类型,能够有针对性地制定故障检修策略,提升故障处置效率。配电自动化设备作为配电网故障快速辨识与处理的重要载体,对故障分类的原理及效果差异性较大,准确率无法满足电力系统工作需求,为此提出一种基于分类回归树与多核残差网络(classfication and regression tree and multi-core ResNet, CART-MRN)的树状结构故障类型识别方法。首先,建立树状故障分类结构,利用Fourier变换、经验模态分解(empirical mode decompsition, EMD)分解等方法提取故障点电压电流的多域故障特征;其次,结合特征分析与信息增益建立适应不同小电流接地系统的融合算法模型,并引入粒子群算法优化网络超参数;最后,通过现场录波数据验证与对比实验,证明该方法能快速、有效地完成单相接地故障分类识别,且更具有适应性。
基金supported by the National Natural Science Foundation of China(Grant Nos.51079043,41172204)the Program for Non-profit Industry Financial Program of Ministry of Water Resources(Grant Nos.200901064,201001020)the Research Innovation Program for College Graduates of Jiangsu Province(Grant No.CXZZ11_0450)
文摘In this article,the Non-Aqueous Phase Liquid（NAPL）transport in the single filled fracture was studied with the Shan-Chen multi-component multiphase Lattice Boltzmann Method（LBM）with special consideration of wettability effects.With the help of the model,the contact angle of the non-wetting phase and wetting phase interface at a solid wall could be adjusted.By considering a set of appropriate boundary conditions,the fractured conductivity was investigated in condition that the NAPL blocks the channels in the single filled fracture.In order to study the wettability effects on the NAPL transport,a constant driving force was introduced in the Shan-Chen multi-component multiphase LBM.Flow regimes with different wettabilities were discussed.Simulated results show that the LBM is a very instrumental method for simulating and studying the immiscible multiphase flow problems in single filled fracture.
文摘配电变压器无触点有载调压技术对稳定电压具有重大意义。有载调压控制系统的耐压问题是限制无触点有载自动调压配电变压器工程应用的关键因素,上电时无触点配电变压器的自启动是另一难点。为解决这2方面的问题,文中设计出一种配电变压器无触点有载自动调压的新方案,其控制系统的电源和测量电压均取自高压(10 k V)分接头,解决分接开关与控制系统的耐压问题;分接开关和控制系统采用悬浮地技术解决对地耐压问题;采用无源自取能触发方式,并利用一组有载调压分接开关在配电变压器上电时实现自启动。模拟实验、理论分析以及近一年的运行试验考核表明,该方案可较好地解决耐压问题,且启动可靠,稳压效果平稳,具有实际应用价值。
