基于GSM短消息的测试数据远程传输技术研究

远程数据采集系统广泛用于远程技术支援,但一些传统的远程数据采集系统具有一定的缺点和不足,如造价较高,维修不便。在数据量不是很大,实时性要求不是很高的场合,利用GSM短信进行设备测试数据的远程传输是一种较好的选择。设备测试数据的远程传输系统利用文本文件读取信息和测试数据,将信息和数据编码成数据包,并将串口通信技术、多线程技术应用于GSM短消息数据包的远程传输过程中,接收到信息之后进行数据包的解码和数据的分析。文中给出了利用Visual C＋＋6．0串口通信技术开发基于GSM短消息的设备测试数据远程传输系统的关键部分和软件开发流程图。目前该系统已成功应用于设备监测现场,取得了良好的效果。     

智能电网建设助推电动汽车业快速发展

电动汽车业的发展,是改变交通模式及能源消费结构,加速我国实现低碳经济目标的有效途径。分析了电动汽车业的发展对电网规划、建设、运行、服务方面带来的挑战,说明了智能电网是电动汽车规模化应用的基础,介绍了智能电网中柔性充放电、双向互动、集中监控、商业运营技术的电动汽车能源供给技术研究及实践情况,对电动汽车业发展的创新商业运营模式进行了展望。     

华东电力节能减排监管现状及措施分析

介绍了华东能源环境现状,将华东电力的生产、运输、分配和消费等环节的能耗和排放指标和国际先进水平相比较,评估华东区域电力节能减排的潜力。针对华东电力节能减排监管存在的问题和不足,从华东电力市场、可再生能源监管、燃煤机组烟气排放监管和电力节能减排监管信息公开等4个方面提出了具体的监管措施。     

Robust control of an isolated hybrid wind-diesel power system using Linear Quadratic Gaussian approach

This paper presents the application of the Linear Quadratic Gaussian (LQG) controller for voltage and frequency regulation of an isolated hybrid wind-diesel scheme. The scheme essentially consists of a vertical axis wind turbine driving a self-excited induction generator connected via an asynchronous (AC-DC-AC) link to a synchronous generator driven by a diesel engine. The synchronous generator is equipped with a voltage regulator and a static exciter. The wind generator and the synchronous generator together cater for the local load and power requirement. However, the load bus voltage and frequency are governed by the synchronous generator. The control objective aims to regulate the load voltage and frequency. This is accomplished via controlling the field voltage and rotational speed of the synchronous generator. The complete nonlinear dynamic model of the system has been described and linearized around an operating point. The standard Kalman filter technique has been employed to estimate the full states of the system. The computational burden has been minimized to a great extent by computing the optimal state feedback gains and the Kalman state space model off-line. The proposed controller has the advantages of robustness, fast response and good performance. The hybrid wind diesel energy scheme with the proposed controller has been tested through a step change in both wind speed and load impedance. Simulation results show that accurate tracking performance of the proposed hybrid wind diesel energy system has been achieved.     

A novel approach of reference current generation for power quality improvement in three-phase, three-wire distribution system using DSTATCOM

This paper presents a novel approach based on an improved instantaneous active and reactive current component theory for generating reference currents for distribution static compensator (DSTATCOM). Three-phase reference current waveforms generated by proposed scheme are tracked by the three-phase voltage source converter in a hysteresis band control scheme. The performance of the DSTATCOM using the proposed control strategy has been evaluated under various source and load conditions. The performance of the proposed control strategy has been evaluated in terms of load balancing, reactive power compensation, compensator rating and harmonic mitigation. A three-phase, three-wire distribution system supplying star connected linear as well as non-linear unbalanced load is considered for simulation study. The detailed simulation results using MATLAB/SIMULINK software are presented to support the feasibility of proposed control strategy.     

铅酸蓄电池铸焊应用综述

与手工烧焊相比,铸焊有着无可比拟的优势,良好的铸焊质量与模具制遣工艺和现场生产控制工艺密切相关。本文结合生产实际对铸焊工艺做了系统的研究阐述,对焊接质量的核心问题“连接强度”进行了分析,并且为保证高质量的连接强度提出了工艺参数要求,对焊接缺陷进行了归类并提出了应对措施。     

直吹式制粉系统W火焰锅炉混煤掺烧试验研究

在直吹式制粉系统W火焰锅炉上进行对比试验。试验表明:不同煤种采用磨内掺混、炉内混烧的方式难以掺混均匀,难燃尽煤种细度难控制,燃烧稳定性、经济性差;分磨制粉、炉内掺烧的方式煤粉细度可控,不同煤种燃烧器可均匀投运,并可采取不同的配风和燃烧控制方式,炉膛温度均匀,燃烧稳定,锅炉热效率比磨内掺混、炉内混烧提高1.65%。     

电工电子学开放性实验教学探索

开放性实验教学是指实验时间、空间、教学内容和方法等都是开放的。学生可以随时进入实验室,进行实验设计和调试,并最终独立完成实验。开放性实验能够调动学生学习的主动性和独立思考的能力,激发学生参与科研的兴趣和创新意识,对学生树立理论联系实际的理念,培养分析问题解决问题的能力有着重要的作用。本次进行的数字钟电路设计与实现实验,使我们首次学会自己动手设计实验方案,制定实验步骤,实施实验过程,讨论实验结果,在查阅文献资料的过程中学习和巩固理论知识;同时也锻炼了我们的动手能力,培养了我们发现问题、解决问题和团结协作的能力。     

新能源与电网规划建设

探讨了在低碳观念逐渐普及、新能源方兴未艾的新形势下,电网应该抓住前所未有的巨大机遇,调整电网规划思路,提高发电比重、预留新能源电源点及其接入通道,大幅扩大电力市场规模,做大做强电网,使电网成为全社会能源供应的主平台。     

基于扰动观察法的最大功率跟踪的实现

对光伏并网逆变系统最大功率算法中的扰动观察法的实现问题进行研究。在分析光伏电池伏安特性的基础上,提出扰动观察法的实现算法。通过比较前后两次功率的大小来决定光伏电池电压扰动的方向,使光伏电池最终达到最大功率点。最大功率跟踪过程中直流侧存在功率脉动,干扰最大功率判断。合理设置滤波算法和采样周期,可滤除直流侧功率脉动。通过设置直流电压控制环节,使系统在最大功率跟踪过程中直流电压保持平稳。实验结果表明,该算法可有效跟踪光伏电池最大功率点,适用于光伏并网逆变系统。