随着高电压等级网架的成熟完善,电磁环网解环实现分区运行,已成为电网发展的必然趋势.论述了电网解环分区供电的原则和方法,结合河北南网"十四五"期间规划数据,重点讨论了2021 年河北南网的电磁环网.通过基础潮流计算分析、短路电流扫描和N-1 校验,结合地理接线图提出解环及分区供电方案,并在仿真计算后得到有效验证.

在利用原有方法进行电网供应链稳态管控时,识别的风险点不够全面,导致无法进行电网供应链风险评估,且评价标准在76.23％～92.23％的范围内存在供应链节点稳定率较低的问题,因此本文提出一种基于模糊综合评价模型的电网供应链稳态管控方法.通过对电网供应链的结构分析,结合德尔菲法和流程分析法,全面识别电网供应链运行流程中的显性风险与隐性风险.构建电网供应链风险评估模型,并基于模糊综合评价模型构造评估矩阵对电网供应链风险评估模型中的风险因素进行评估.通过对比实验验证,设计方法使评价标准在76.23％～92.23％范围内的供应链节点稳定率高于原有方法,提高了电网供应链稳态管控的稳定性.

可再生能源(Renewable Energy Source,RES)发电固有的间歇性和波动性给其并网消纳造成了困难.虚拟电厂(Virtual Power Plant,VPP)是聚合分散分布的RES并对其进行统一协调管理的有效方法.首先,深度挖掘负荷侧供能潜力,提出可控负荷概念,并建立可控负荷储备率函数和可控负荷参与度指标.然后,建立包含可控负荷、传统电厂、随机性可再生能源的VPP模型;以VPP时序上网功率稳定性最大为目标,兼顾风光有效消纳,建立考虑可控负荷参与的VPP协调优化调度模型,该模型为典型二次规划(Quadratic Programming,QP),采用LINGO软件进行求解.最后,对IEEE14标准算例进行仿真分析,结果表明可控负荷参与下的VPP能有效改善负荷峰谷时段和新能源出力波动较大时段的系统运行特性,VPP整体出力平稳,且出力水平较高.

阐述了传统物流管理和现代供应链管理的内涵,分析了传统物流管理与现代供应链管理的区别,探讨了传统物流管理向现代供应链管理模式转变的意义,提出传统物流管理向现代供应链管理模式转变的策略,以期为物流业发展提供参考.

In order to realize the abnormal condition detection and analysis of the wind turbine generator,a deep learning method of stacked autoencoder(SAE) network is proposed based on condition monitoring data of supervisory control and data acquisition(SCADA) of wind turbine generator.The SAE network is composed of multiple autoencoder networks,and the normal generator SCADA state variable data is selected as the training input of the network.The distributed rules are extracted intelligently from the network layer by layer to build the SAE learning model.Because internal dynamic balance rules of the generator SCADA data are destroyed under the abnormal state,the reconstruction error is calculated using the initial input and reconstruction values as the observation of the whole state.Adaptive threshold is used to detect the trend of the reconstruction error and as a criterion for abnormal early warning to detect generator abnormal condition.When the generator is abnormal, there is a larger deviation between the actual value and its reconstruction value.So the residuals trend of the state variables will deviate from the original dynamic stability state.The trend change of the state variable residual will be used to isolate the abnormal variables to locate the generator fault and achieve the purpose of fault diagnosis.The simulation results show that the SAE network deep learning method is effective for condition monitoring and fault diagnosis of generator.

As the capacity percentage of renewable energy power generation will increase and the role of traditional thermal power units will change from supporting mediate load to deep participating in peak regulation,the torsional life loss of turbine-generator caused by the quick and frequent power output regulation is studied.The finite element analysis software ANSYS is applied for building the models of turbine-generator shaft system to obtain the torsional response of dangerous shaft segment and the rain-flow counting method is used to convert the working cyclic stress into the symmetrical cyclic fatigue stress.With the consideration of the frequent load fluctuation,the Manson-coffin strain-life formula is combined with the continuum damage mechanics to evaluate the torsional life loss of shaft system.With domestic 600 WM supercritical turbine-generator as an example,the relationship between the torsional life loss and the fluctuation/randomness of load is studied by simulation.The life loss grows exponentially with the increase of ramping rate or peak regulation range.For balancing the life loss of turbine-generator and the accommodation of renewable energy,the key of thermal power units deeply participating in the peak regulation is to select suitable ramping rate and peak regulation range according to the operational characteristics of unit.When the frequent load fluctuation is considered,the torsional life loss conforms to the accumulation rules due to the faster attenuation of torsional oscillation.

灵活性反映电力系统在一定时间尺度下响应供需两端变化的能力,研究灵活性对分析可再生能源接入问题有重要的意义,因此需要分析可再生能源与传统电源之间的制约关系。根据传统电源爬坡率的特点,提出机组灵活性和电力系统传统电源灵活性的量化指标,利用蒙特卡罗模拟的方法给出相应的计算流程。相比其他灵活性指标,所提灵活性指标能够评价机组灵活性的高低,表征各机组对传统电源灵活性的贡献,同时,还可计算出系统消纳可再生能源发电的能力。最后以IEEE-9机57节点系统为例,计算所提灵活性指标,得到机组灵活性的高低和消纳可再生能源的能力。结果表明所提指标是准确有效的。