在积极推进新工科建设的背景下,在几十年教学实践的基础上,立足农业院校电气类专业实际,开展沈阳农业大学电气类专业课程建设研究.经过教学团队多年的积淀和传承,沈阳农业大学电气类专业课程建设目标明确,课程建设成果显著,已形成了集立体化的课程育人体系、多元化的课程教学体系和多样化的课程评价体系于一体的较为健全的课程建设体系.秉承立德树人理念,依托新工科建设,沈阳农业大学电气类专业课程建设将面向未来形成特色,并持续改进不断提升.

该文对可再生能源发电并网逆变器虚拟同步发电机(VSG)控制策略进行研究,针对传统VSG不能兼顾动态调节特性与稳态性能这一缺陷,提出一种改进的虚拟同步发电机控制策略.在传统同步发电机本体控制算法数学模型分析基础上,建立虚拟同步发电机有功功率对于频率波动的闭环传递函数,研究动态过渡过程中转动惯量与阻尼对有功功率响应的影响机理.在传统VSG功频控制器中引入导前微分控制环节与惯性校正环节,提出基于导前微分控制的改进虚拟同步发电机功频控制策略,建立有功功率对于频率波动的闭环传递函数,分析离网与并网状态下的功频特性.通过对导前微分环节控制参数的调节,抑制过渡过程中的功率振荡,实现VSG动态特性与稳态性能的解耦控制.

植物柔性传感器具有轻量化、透气、植物表面共形性高等特点,可以实现无损、实时、原位监测,提供精准的植物生理与环境信息,实现植物语言识别,开创"植物半导体新赛道".介绍了柔性电子技术在植物健康监测方面的最新进展,概述了植物柔性传感器用于植物激素、信号分子、植物电信号、挥发性有机物等的监测,可有效反映出植物健康状态;通过监测地表和空气中植物代谢产物反映环境胁迫条件,分析了新型植物可穿戴设备的传感技术,制备材料、结构以及监测方法.最后,对植物柔性传感器在现代农业中的应用进行总结,并讨论了未来植物可穿戴设备面临的机遇和挑战.

文章主要对新工科背景下多方协同育人的"工程实践"教学模式展开研究.在对现阶段地方高校构建多方协同育人实践教学模式所面临的问题进行分析的基础之上,结合具体建设内容提出建设目标.并进一步设计出具体建设措施:首先,以强化学生工程实践能力培养为目的,设计"闭环式"多方协同人才培养方案;其次,以政、校、企合作优化资源配置为手段,基于"一体系、双平台"思想构建多层次实践教学平台;再次,以"多元化"考核为依托,重构学生学习效果评价方法;最后,以持续建设"双师"型教师队伍为保障,推进校企协同培养模式.

本着全力建设新工科和全面振兴本科教育的发展理念,立足沈阳农业大学电气类专业,对沈阳农业大学电气类专业实践本科生导师制的优势、劣势、机会和威胁进行详尽分析.在SWOT分析的基础上,根据遵循“以本为本”教育理念、顺应新工科发展方向、符合电气类专业特点、适合农业院校学情的本科生导师制的实践依据,利用SWOT矩阵开展了电气类专业进一步实践本科生导师制的对策研究.

New energ y acce ss t he power distribution system on the large scale, increases the uncertainties of the operating parameters of power system. There are two aspects to the key issue of achieving the new energy grid system stable operation:establishing reasonable optimization model of photovoltaic power generation grid-connected system, and providing the voltage limit interval and system rational "carrying capacity" based on stable operation conditions. Therefore, we put forward the application of the interval optimization algorithm for realizing the operation parameter optimization of PV grid-connected system. The power source capacity of the photovoltaic power grid node was used as the objective function, and the distribution network node voltage and branch power characteristics as the constraint conditions, a nonlinear model of the interval optimization was created in regard to the photovoltaic power generation system. The deterministic model transformation of objective function and constraint condition using the interval possibility and interval order relationship were completed. Two nested interval optimization functions were established in order to achieve the minimum node voltage fluctuations and the minimum network active power loss. The interval boundary function of the active capacity and the node voltage as the constraint condition. It sets up the optimization model of multi-node PV grid-connected system was used to combine the active power inequality constraints and the regulation of PV grid-connected. The optimal solution of robustness was obtained. The simulation of IEEE 33 node power distribution system had the best effect to improve the voltage of the end node of the distribution network. The voltage of the end node was enhanced by 3.3% - 11.8%, with the optimal range of the end node voltage lower boundary [9.8277, 9.8367], the accuracy of node voltage lower boundary being from -5% to -1.72% the optimal range of active power loss being [131.6576, 143.4365] with the reduction of the active power loss by 63.8% - 66.8% compared with no PV grid-connected system. The first-end power optimization interval was [30.446, 354.59], achieving the active power maximum adjustment peak 354.59kW, which provided the reliability of the operation for the photovoltaic power grid-connected system. The method had the characteristics of high precision and fast convergence suitable for improving the condition of the voltage at the end of the rural distribution network. The PV grid-connected configuration scheme could be provided by utilizing the interval optimization method, which could provide an important theoretical basis for the future power distribution network reconstruction.

风电并入电网时,风的波动性和随机性会对电网的稳定运行带来不利的影响.通过分位数回归对风电场发电功率进行预测,可以尽量提前避免由于风力波动对电网造成的不利影响.运用Eviews软件对历史风速和风功率数据进行分析、建模和预测,实现了较好的预测效果.

In view of the nonlinear and non-stationary characteristics of wind power time series,this paper presents a modified ensemble empirical mode decomposition (MEEMD)-sample entropy (SE)-ARMA wind power ultra short term combined forecasting model.The white noise signal added in the EEMD decomposition is changed to two groups positive and negative white noise signal which have the equal absolute value,and the EMD steps of the decomposition process of MEEMD is improved with the endpoint extension and three piecewise Hermite interpolation,forming a modified EEMD decomposition algorithm (MEEMD).The wind power time series is decomposed into a series of complex wind power generation by MEEMD-SE,and the ARMA forecasting model is built for each different sub sequence,and the final wind power forecast value is obtained.Through numerical analysis and comparison with other forecasting models,the results show that the MEEMD-SE-ARMA combination forecasting model can effectively improve the accuracy of the ultra short term forecasting of wind power generation.

ABSTRACT:In order to mine the deep information contained in the wind power big data and explore the law of the wind farm operation and offer guidance for the practical wind farm operation in a scientific, proper, and economical way, the research on the wind power farm operation data analysis is done in this paper. With the operation data of the SCADA system of the wind turbine generator as the main research target,with analysis of the power big data as the basic train of thought,and econometrics and statistics as the main research method,this paper proposes the level structure of wind power farm data analysis,and summarizes the classification frame structure and analyzes the performance characteristics of the various parame-ters of the wind turbine generator and verifies the necessity of research in the current hot points in the wind power sector based on the data analysis.

风力发电由于其清洁性、波动性、随机性及不稳定性,向电网输送绿色电能的同时也对电网的可靠运行造成了一定的冲击,因此风电发电量预测的准确性对电网科学合理调度、安全稳定运行具有至关重要的作用。以大数据分析、多学科交叉融合为背景,以负荷预测为基础理论,利用计量经济学分析方法对风电场月发电量数据进行分析、建模和预测。对辽宁地区某49.5 MW风电场月发电量数据进行收集整理,利用计量经济学分析软件EVIEWS对采样数据进行分析,并采用SARIMA模型对风电场月发电量数据进行拟合和预测,达到了较好的预测效果。

农村电网“低电压”问题已经成为影响供电企业运营的重要制约因素.与高压输电网不同,农村低压配电线路长度和有功功率对线路末端电压影响较为明显,不能依靠高压输电线路的无功补偿方法达到有效治理低电压的目的,应该充分考虑有功功率、线路电阻参数和分布式电源接入位置的影响.文章分析了分布式电源对于农村电网低电压的治理效果和适应性.仿真结果表明,分布式电源接入线路末端,低电压治理效果明显;通过优化三相功率分布,有助于解决农村电网存在的三相电压不平衡带来的低电压问题;协调控制分布式电源,可以为农村电网低电压治理提供有效的解决方案.

本着以人为本,与时俱进的教育教学理念,通过不断的实践与探索,本文分别以复合型人才培养、导师制、职业化为研究背景,阐述了沈阳农业大学电气工程及其自动化、农业电气化与自动化专业的本科生教育实践,倡导整体提升、个性开发、创新发展的培养方式,探索出了适合我校电类专业本科生教育的教育教学模式.

Wind power prediction is very important to improve the power quality and the safe operation of power sys -tem.The ultra short-term prediction of wind power data is carried out in a wind farm in Chifeng of Inner Mongola based on time series analysis , and the ARMA ( Autoregressive Moving Average ) model of time series is built through the stationary test of data.Through ARCH effect of the residual of ARMA model by Lagrange Multiplier (LM), the corresponding ARMA-GARCH model is set up .Through the comparison of the wind power prediction by using ARMA model , ARMA-ARCH model and ARMA-GARCH model respectively , ARMA-GARCH model possesses higher accura-cy on the residual sequence of the data with the long term correlation .

<正>我国风电产业发展迅速1.我国风力发电总装机容量已位居世界首位,风力发电已成为我国第三大电源2012年11月15日于北京举行的国际风能大会暨展览会上,国家能源局副局长刘琦发表讲话指出,中国是目前全球风电装机排名第一的国家,预计将超过6000万kW,发电量超过1000亿kW·h,成为中国第三大电源。毫无疑问,风力发电在许多国家已成为电力系统的主要发电形式,其提供了经济可靠的电能。据世界风能协会

Single phase-to-ground fault-detection for neutral non-effectively grounded distribution system has been a challenge for many years, but the research has been mainly concentrated on permanent grounding fault, which is not general. Actually, unstable arc-grounding and intermittent arc-grounding faults which are kind of non-permanent grounding faults most likely to occur in the power system. When arc-grounding fault happens, many high frequency components will be produced correspondingly. A novel method is introduced in this paper according to the research results that are conducted from the research on the singular character of zero-sequence current with the time and frequency localization character of wavelet transform. The Matlab simulation results show that the proposed method can find the fault feeder correctly when single phase intermittent arc-grounding fault occurs. The principle is reliable and accurate.

Power system signal analysis becomes more and more important as the power system is rapidly developed. This paper gives an improved phase-locked loop (IPLL) structure for the application needs of power quality detection, power conversion systems, power systems protection, and so on. Mathematical model is analyzed with control theory. The functions of the IPLL are showed based on Matlab/simulink. The analysis mentioned above shows that IPLL can extract phase, frequency, amplitude and also fundamental wave. The applications of the IPLL don’t need αβ transform and dq transform compared with conventional phase locked-loop. This is a new choice for power system signal analysis application.

<正>在建设风场时,需要注意和控制的环节很多,从风力发电机的基础施工、风力发电机吊装以及各种设备的调试等,任何一点的疏忽都可能导致破坏性的严重后果。而在风力发电机安装的众多环节中,螺栓的安装质量是否合格对风力发电机的安全和以后运行有着举足轻重的作用。本文介绍了在风场风力发电机的安装过程中关于螺栓力矩的简单计算和安装应该注意的几个问题,对业主在风场建设

Based on the "Electrical Engineering CAD" program this paper explored and deeply analysed the characteristics of "Electrical Engineering CAD" program and the main problems of teaching during this present period.It also has explained at large the combinated teaching mode of explaining,demonstrating and exercising summarized by "Electrical Engineering CAD" program teaching practice,the scientific and rational scheme of assessment and evaluation,by the humanized teaching methods with student centered and the practice teaching exploration of teacher-student and student interaction,and other things.

本文通过对比东北辽宁省某风电场正版可研数据、风电机组的标准功率曲线和现场监控软件的实际功率曲线,结合该风电场风电机组的可利用率,分析了该风电场半年实际发电量与可研数据存在差异的原因,希望对我国其他风电场具有一定的借鉴意义。

由于中美两国高等学校教师来源不同,中国高等农林院校新教师面临心理调试、取得教学经验、提升教师素养、选定专业发展方向和减轻人生压力等方面问题。新教师必须通过角色转换与适应、增加知识储备和工作自信、合理自我定位、培养人生归属感等心理建设;同时再通过准确把握教学环节、掌握高效教学法、激发学生学习兴趣、加强师生互动交流等教学能力建设,适时开展与教学有关的科研工作,提升教师的自身建设,最终成为一名合格的农林院校教师。