基于实测信号的抽水蓄能机组频率自适应算法研究

针对抽水蓄能机组起动运行的实测数据进行时频分析,本文提出了一种针对抽水蓄能机组起动特性和运行特点的软件测频的频率自适应算法。用于精确计算各种运行工况下对抽水蓄能机组的电压和电流值,同时针对在信号波动的过程中,提出非周期分量的滤除方法,并将该算法应用于故障录波装置中的录波分析软件,仿真表明该方法抗干扰性好,测量精度高,能满足实际应用中的频率测量要求。     

GB/T18482-2001《可逆式抽水蓄能机组起动试验规程》简介

可逆式抽水蓄能机组除具有发电工况的起动运行方式外,还具有水泵工况的起动运行特点,因此它比常规水轮发电机在设备和技术等方面都要复杂.国内已有潘家口、广蓄Ⅰ期和Ⅱ期、十三陵、溪口和天荒坪等电站投入运行.近年来我们对上述电站机组起动试验进行分析和总结,并吸取国外先进国家相关技术标准,经过各方努力,完成了国家标准《可逆式抽水蓄能机组起动试验规程》(GB/T 18482-2001)的制定,这也是国内第一部有关抽水蓄能机组的国家标准.这一标准的颁发和实施,将对我国今后多座大中型抽水蓄能电站的机组起动试验起到重要的指导作用.现将规程主要内容简单介绍如下.     

抽水蓄能机组微机励磁控制器的研制

抽水蓄能机组励磁控制器具有工况转换频繁,逻辑控制严密,需采取电气起动和制动等特点,国内目前尚无大型抽水蓄能机组微机励磁控制器研究成功的报道.从分析抽水蓄能机组的特点出发,以80C196十六位单片机为核心控制芯片,从硬件设计和软件编程方面详细介绍了抽水蓄能机组励磁控制器的研制.通过实验室样机调试,结果表明,该16位单片机构成的抽水蓄能机组励磁控制器具有体积小,线路简单,运行可靠,易于调试、维护,且控制精度高等优点.能够满足抽水蓄能机组发电、抽水、起动、电气制动等各种运行工况之间相互转换的要求.     

抽水蓄能机组双微机励磁系统的研制

本文根据抽水蓄能机组励磁系统的控制及运行特点,对抽水蓄能机组的电气起动投励、主回路选择、STD 工控机微机调节器硬件、软件设计及系统可靠性方面进行了研究与分析。为大型抽水蓄能机组励磁控制设备的国产化设计应用提供了经验。     

国产抽水蓄能机组成套开关设备的发展

<正>介绍了抽水蓄能机组成套开关设备中存在的问题及在实际运行中的功能需求，以及国内外抽水蓄能机组成套开关设备发展现状，从技术参数、结构特点及成套供货能力等几个维度对国内外产品进行了对比分析。抽水蓄能电站具有调峰、调频、调相、储能、系统备用和黑起动等多种功能，是当前技术最成熟、     

抽水蓄能电站的一种特殊运行方式

研究用于分析羊卓雍湖电站三机式蓄能机组三机同时运行方式的数学模型及其解法，在此基础上算出电机输入功率与入库流量，水泵抽水效率等之间的关系．当入库流量为零时需消耗电网约４０００ｋＷ的电能，当电网可供抽水的剩余功率大于４０００ｋ，则水泵抽水的流量除一部分回流至水轮机外，还有一部分流至羊卓雍湖蓄能，这就充分利用系统中小于一台泵额定功率的多余功率，提高经济效益．分析利用同轴水轮机来完成的水泵起动和停运过程，说明蓄能泵起动和停运过程都可做到对电网无瞬时负荷冲击．还提出一种利用同轴水轮机改善水泵断电过渡过程的方法．     

抽水蓄能电站发电电动机起动仿真计算研究

本文介绍了抽水蓄能发电电动机的主要起动方法以及应用SIMSEN仿真计算软件对白莲河抽水蓄能发电电动机的两种主要起动方式的仿真计算研究。     

大型抽水蓄能机组的变频起动

现代大型抽水蓄能机组大都采用变频器方式进行启动。本文将从蓄能机组变频起动的工作原理和控制过程分析入手，介绍我国首次采用变频器对机组进行控制的电站－潘家口抽水蓄能电站的机组变频起动的调试结果。     

抽水蓄能机组静止变频器起动控制系统半实物仿真

静止变频器(SFC)起动已经成为抽水蓄能机组起动普遍采用方式。对抽水蓄能机组的静止变频器起动控制策略进行了深入研究。通过实时数字仿真系统(RTDS)与SFC实物控制器装置相结合构建了半实物仿真试验平台,验证了所采用的变频起动控制策略的正确性。     

响洪甸抽水蓄能机组调试及运行

本文介绍响洪甸抽水蓄能机组投运调试情况。包括主机、辅机、自动化及监控程序的调试工作,叙述了一些主要的调试项目及调试结果,对有关水泵起动的一些关键技术环节作了简要说明,为今后机组的运行及抽水蓄能新机组的设计与制造积累了经验。     

Digital protective relaying algorithms and systems — An overview

This paper gives an overview of the digital algorithms and systems for protective relaying. First, digital relaying algorithms are discussed. Classification and categorization of the proposed algorithms are given. The major classes are: transmission line protection, transformer protection, bus protection, and generator protection. The categories correspond to the different schemes used for the signal processing. The discussion of algorithms is concluded by giving some basic results related to the comparison and selection of the algorithms. A particular methodology is proposed if one is to investigate and compare digital algorithms using more elaborate quantitative techniques. The second major topic discussed is related to the digital implementations of the protective relays. Major philosophies used in designing digital relaying systems are outlined. These philosophies include the following design approaches: a centralized relaying system using a minicomputer; a decentralized relaying system where each protection function is implemented using a separate microprocessor; an integrated relaying system where a number of dedicated microprocessors are connected together in a protection system; an integrated substation control and protection system. Finally, expected trends in the areas of algorithm developments and system implementations are indicated.     

网络图论方法在继电保护数字仿真中的应用

本文简要介绍了继电保护数字仿真的几种研究方向，并对其进行了评价。     

Microcomputer based digital differential relaying for generator protection: Real time test results

The paper presents the development of a digital differential relaying scheme around a 16-bit microprocessor for generator winding protection. It uses a simple filter algorithm which is based on cross-correlation with a heptagonal wave for the extraction of fundamental frequency components of differential and sum currents. Application of this filter and use of the real parts alone, instead of both the real and imaginary parts, of the fundamental frequency components for the relaying reduces the computation requirement drastically, thus enabling implementation of a complete three-phase differential relay on a single microprocessor without requiring a coprocessor or multiplier. The relay has been tested in real time on simulated generator currents representing internal-, external- and no-fault conditions separately. The test results agree well with the results of off-line evaluation reported earlier and point to a successful implementation of the differential relaying algorithm on a microprocessor in real time.     

Novel microprocessor based negative phase sequence relay and meter

Microprocessor application in relaying and condition monitoring technology is becoming increasingly popular. In this paper, a novel microprocessor based negative phase sequence (NPS) current detector for motor condition monitoring and relaying for motor/generator protection is developed. The proposed meter eliminates the need of a negative phase sequence filter and does not require complicated digital signal processing techniques. Instead it uses a phase sensitive rectifier. A prototype based on Intel's 8085 A microprocessor was built and tested. Complete circuitry, main and interrupt software flowcharts are provided. Results show the proposed NPS relay and meter can provide a high degree of accuracy and satisfactory results.     

Applying CTs with digital ground relays

Industrial power distribution system substation transformers and generator step-up transformers in power stations often use resistance-grounded wye secondary windings for medium-voltage power distribution. The purpose of this is to limit damage due to ground-fault currents, while providing sufficient fault current for the operation of ground-fault relaying. The relaying used to protect against ground faults in the system may not provide sufficient protection of the transformer winding against internal faults because the backup ground overcurrent relay in the transformer neutral-to-ground connection must be set to coordinate with downstream relays. In order to protect the winding itself, special relays are utilized. Ground differential protection can be provided by digital overcurrent relays in conjunction with auxiliary ratio matching transformers. Ground differential protection can also be provided in multifunction digital relays. Transformer protection relays may include this feature with one of the schemes used with component relays. If a feeder-protection relay is used on the secondary, in some cases, this may have a ground-directional feature that can be utilized for ground-differential protection     

A new distance relaying algorithm based on complex differential equation for symmetrical components

This paper presents a new digital impedance measuring technique for transmission lines that combines symmetrical components and the complex differential equation of an equivalent fault loop circuit. The phase voltages and currents at the relaying point are transformed into symmetrical components using Fourier filters of short window length. Depending on fault type, an appropriate fault loop circuit is formed, signals of which are the appropriate symmetrical components, while a parameter of which is the positive sequence impedance being a geometrical measure of the distance from the relaying point to a fault. The impedance, however, is measured very fast by on-line solving the complex differential equation originated for this fault loop circuit. Consequently, this approach combines frequency domain estimation of symmetrical components (accurate filtration) and time domain measurement of positive sequence impedance (high speed response).

The presented method suits well the protection of parallel lines against high-resistance faults occurring very close to the far end of a line. A new method is proposed for detecting high-resistance faults and deciding which line out of two parallel lines actually suffers a fault.

The included EMTP test results demonstrate the efficiency of the proposed relaying algorithm.     

Protection of the Induction Motor/Generator

This paper covers a brief review of the induction generator theory. The equivalent circuit is covered along with comment on performance characteristics. The application involving the relaying of induction generators can be simple to complex depending on the process requirements. As an example, the induction generator can be connected to an expander in the natural gas system with a minimum of relaying, or it can be used as a motor to help accelerate a multi- element train and function as a brake for the multi-element train and thus complicate the relaying. A more complicated application is analyzed and relaying suggested.     

Educational use of EMTP MODELS for the study of a distance relayingalgorithm for protecting transmission lines

This paper presents the implementation of a distance relaying algorithm using EMTP MODELS, in which we have simplified the procedures of system modeling and distance relaying system by using a single structure of MODELS. The technique presented is based on integrating the modeling of the power system and the protective system in one program module. The purpose of this paper is to provide systematic relaying concepts by modeling a digital relaying system using MODELS functions within EMTP in a closed-loop manner, principally to facilitate and enhance an understanding of the basic concepts of distance relaying of final year undergraduate students/postgraduate students/young engineers who are new to the subject of power system protective relaying. Various elements of digital distance relaying are organized to generate a systematic approach to modeling the actual hardware of digital relaying systems. Case studies relating to the most commonly encountered single phase-to-ground fault and phase-to-phase fault are presented and various fault distances and fault inception angles are considered     

微机型继电保护测试用模拟断路器的研制

目前市场上销售的模拟断路器大多数不能与微机型继电保护测试装置配合使用，少量可配合使用的模拟断路器价格又普遍较高，可靠性和抗干扰性较差。为解决这一问题，研制了一种以数字电路为核心的集成电路模拟断路器。它由“主回路”、“控制回路”和“保护回路”三部分电路组成。此模拟断路器具有造价低、功耗小、计时准确并可与微机型继电保护测试装置相配合来检测成套保护装置等特点。大量试验证明它还具有工作可靠和抗干扰性好等优点。     

12脉动桥式换流器数学模型及数字仿真

利用布尔交量推导出了双桥换流器一种新的数学模型。针对高压直流输电单元接线方式，将其与凸极同步发电机及三相三绕组变压器模型结合在一起，构成了带有非正弦负荷的凸极同步发电机系统模型。最后给出了数字仿真结果。