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1、PQPQ测量量仪器和技器和技术基基础(1)(1)LuisIntroduction to 3 Phase Power Company Confidential 2 Electricity is generated by conductors rotating though a magnetic field电是由在磁场中旋转的导体电是由在磁场中旋转的导体产生的产生的Pick a point on a circle, rotating counterclockwise at a fixed speed. When the angle is small the change in height is
2、rapid. As the angle increases towards 90 the change in height slows. The distance from the “the horizon” sweeps out a sine wave. 在圆周上选一个点,该点以固定速率在在圆周上选一个点,该点以固定速率在圆周上向逆时针方向旋转。当旋转的角圆周上向逆时针方向旋转。当旋转的角度比较小时,高度的变化就比较明显;度比较小时,高度的变化就比较明显;当旋转角度向当旋转角度向90方向增长时,方向增长时, 高度的高度的变化也组件减缓。偏离变化也组件减缓。偏离“水平水平”方向的方向的高度即形
3、成了一个正弦波。高度即形成了一个正弦波。Why Sine Waves ?为什么会是正弦波?为什么会是正弦波?LuisIntroduction to 3 Phase Power Company Confidential 3 Why 3-Phase?为什么为三相?为什么为三相? At any instant the net current on the neutral is zero. Try it!在任何情况下,零线上的净电流为零。试试看! Three phase motors have better starting torque, run more quietly, are more eff
4、icient and are smaller than singlephase motors of similar hp rating三相马达具有更好的起动扭矩、运行更平顺、更有效率,并且体积比相同马力的单相马达更小。 If you add more than three phases it adds more cost but doesnt deliver significant performance improvements如果相数多余三个,会增加很多费用,但是性能并没有明显改善。Three individual voltage phases typically 120 degrees
5、out of phase of each other.三个独立的电压相位彼此之间一般相差120度。Three individual current phases typically 120 degrees out of phase of each other.三个独立的电流相位彼此之间一般相差120度。Voltage and current will typically be shifted from each other resulting in “power factor”电压和电流的相位一般不一致,所以就有了“功率因数”LuisIntroduction to 3 Phase Power
6、Company Confidential 4 Vector Representation矢量表示矢量表示Note that the vectors go in the counterclockwise direction, like the circle in the previous slide注意:矢量呈逆时针运动,类似前面例子中的圆周。注意:矢量呈逆时针运动,类似前面例子中的圆周。LuisIntroduction to 3 Phase Power Company Confidential 5 From the Dam to Your Load从发电站到负载从发电站到负载LuisIntro
7、duction to 3 Phase Power Company Confidential 6 From the Dam to Your Load从发电站到负载从发电站到负载High Voltage (over 100kV) is used for transmission. All 3-phase用于电力传输的高压用于电力传输的高压线路(线路(100kV以上)。以上)。全为三相系统全为三相系统Substations use transformers to step down the voltage to medium voltage (4160 to 14kV).PTs are used t
8、o measure voltage levels.变电站利用变压器将电压变变电站利用变压器将电压变为中压(为中压(4160到到12kV)。)。使用使用PT来测量电压。来测量电压。Medium voltage is used for distribution. Mostly 3-phase.使用中压进行配电。大使用中压进行配电。大多数为三相系统。多数为三相系统。Medium Voltage is stepped down to 240 or 480 for delivery to customers.中压又被变为中压又被变为240或或480伏的电压,然后传伏的电压,然后传输给用户。输给用户。 F
9、uses and circuit breakers保险和电路断路器保险和电路断路器 Protective relays保护继电器保护继电器 Lightning arrestors避雷器避雷器 Switches电闸电闸“Reclosure”自动开关自动开关LuisIntroduction to 3 Phase Power Company Confidential 7 From the Dam to Your Load从发电站到负载从发电站到负载LuisIntroduction to 3 Phase Power Company Confidential 8 Transformer Connecti
10、ons变压器的连接变压器的连接Single-phase systems单相系统单相系统 Three-phase, Four wire systems 三相、四线系统三相、四线系统Three-phase, Three wire systems 三相、三线系统三相、三线系统LuisIntroduction to 3 Phase Power Company Confidential 9 Delta Configuration三角型配置三角型配置Comprised of 3 voltages and 3 currents.由三个电压和三个电流组成No Neutral wire.无零线Sometimes
11、 has a ground wire.有时有地线Voltage is measure as “phase to phase”.测量的电压为“相相”电压Typically 480vrms.一般为480vrms.LuisIntroduction to 3 Phase Power Company Confidential 10 Wye ConfigurationY型配置型配置Almost all commercial and light industrial loads are supplied by Grounded-Y (4-wire Y) transformers. 几乎所有的商业和照明领域的
12、负载都是由几乎所有的商业和照明领域的负载都是由接地的接地的Y型(型(4线线Y型)配置的变压器供电的型)配置的变压器供电的Comprised of 3 voltages and 3 currents.由三个电压三个电流组成Neutral wire and ground wire.零线和地线The Wye delivers two stable voltage levels from one transformer在Y性配置下,变压器可以提供两个电压Phase to Neutral may be used for smaller loads相零电压,小的负载可以使用这个电压Phase to pha
13、se may be used for larger loads or longer wiring runs相相电压,大负载或配线较长时可以使用该电压LuisIntroduction to 3 Phase Power Company Confidential 11 Voltage Levels 电压电压Standard voltage levels vary by country各个国家的标准电压会不一样Most distribution within buildings is 120V to 480V建筑物内的绝大多数配电系统为120V到480VResidential standards va
14、ry considerably 各个国家与住宅有关的标准也不一样US, Canada, Mexico use a 240V single phase system美国、加拿大、墨西哥使用240V的单相系统Europe, China, others use 230V single or 3-phase欧洲、中国以及其它国家使用230V单相或三相系统Typical Wye phase-to-phase and phase-to-neutral voltages are典型的Y型配置下相相和相零电压如下240/120V (US, Canada, Mexico) 240/120V(美国、加拿大、墨西哥
15、)400/230V (China, Europe) 400/230V(中国、欧洲)480/277V (US, Canada, Mexico) 480/277V(美国、加拿大、墨西哥)Voltages from 1kV to 100kV are used to serve large commercial buildings and for utility distribution1kV到100kV的电压一般用于大的商业建筑和公用配电系统Voltages over 100kV are used for transmission超过100kV的电压一般用于电力传输LuisIntroduction
16、to 3 Phase Power Company Confidential 12 Color Codes色标色标Varies by country and territory.各个国家和地区不一致Not always done correctly.不一定都正确使用Bus bar usually not labeled.通常并不标注母线Australia & New Zealand:澳大利亚和新西兰:Red / White / Blue / Black / Yellow Green Strip红/白/蓝/黑/黄色卷带USA:美国:Black / Red /Blue / White / Green
17、黑/红/蓝/白/绿Europe:欧洲:Red / Yellow / Blue / Black / Yellow Green strip红/黄/蓝/黑/黄色卷带LuisIntroduction to 3 Phase Power Company Confidential 13 Let us speak Power关于功率关于功率Three Kinds of AC Power三种交流功率三种交流功率True Power (W)有效功率(有效功率(W)Does useful work做有用功Reactive Power (VAR)无功功率(无功功率(VAR)Powers motor magnetic
18、field, charges capacitor驱动马达磁场、给电容充电Apparent Power (VA)视在功率(视在功率(VA)System capacity系统负载量PF = WattsVolt-AmpsHead = VARs头部头部=乏乏Beer = Watts啤酒啤酒=瓦特瓦特Glass = VA玻璃杯玻璃杯=伏安伏安LuisIntroduction to 3 Phase Power Company Confidential 14 Power Triangle功率三角形功率三角形Motors require “lagging” VARs, reducing PF.Greater
19、system capacity (VA) is required.马达需要马达需要“滞后滞后” 乏,乏,导致功率因数降低,需导致功率因数降低,需要更大的系统负载量要更大的系统负载量(VA)。)。Caps supply “leading” VARs, improving PF, reducing VA requirement.电容能使乏电容能使乏“提前提前”,提高功率因数,减小所提高功率因数,减小所需的伏安。需的伏安。Capsreduce PF电容降低了电容降低了PFReactivePower (VARs)无功功率无功功率(乏)(乏)True Power (Watts)有效功率(瓦特)有效功率(
20、瓦特)Apparent Power (VA)视在功率(伏安)视在功率(伏安)LuisIntroduction to 3 Phase Power Company Confidential 15 What is Power Quality什么是电能质量什么是电能质量“Any power problem manifested in voltage, current, or frequency deviations that results in failure or missed operation of utility or end user equipment”“电能质量就是指出现在导致公用设施
21、或最终用户设备故障或工作不正常的电压、电流或频率偏移上的任何电能问题。Dugan, McGranahan, Beaty; Electrical Power Systems Quality Dugan, McGranahan, Beaty;“电力系统的质量”LuisIntroduction to 3 Phase Power Company Confidential 16 Power Problems电能问题电能问题Voltage sags and outages电压骤降或断电Overcurrent (tripping CBs)过流(启动断路器)Utility Bills电费Energy cons
22、umption能量消耗Peak Demand最高负荷Power Factor Penalties功率因数的影响Voltage swells电压骤升Transients瞬态电压Voltage imbalance/unbalance电压失衡/紊乱Excessive harmonics谐波过多Flicker闪变Noise噪声Ground currents or poor grounding接地电流或接地不良LuisIntroduction to 3 Phase Power Company Confidential 17 Severity of Voltage Events电压时间的安全性电压时间的安
23、全性Most Power Quality events are really voltage events.大多数电能质量时间其实是电压事件Severity of a voltage event is characterized by magnitude and duration.电压时间的严重程度是由幅度和持续时间表示的。The larger the change, and the longer it takes place, the more likely it is that equipment will malfunction.事件的变化越大、持续的时间越长,设备就越有可能出现故障IT
24、IC/CBEMA curves plot magnitude and duration of events that are likely to cause problems with computer equipment. ITIC/CBEMA曲线用来绘制可能会导致计算机设备出现故障的事件的幅度和持续时间。LuisIntroduction to 3 Phase Power Company Confidential 18 Lets Talk About Standards关于标准关于标准There are two important standards that influenced the
25、design of the Fluke 430有两个重要的标准影响着Fluke 430设计IEC 61000-4-30 “Testing and Measurement Techniques for Power Quality Measurement Methods.”IEC 61000-4-30 “电能质量测量的测试和测量技术”EN50160 “Voltage Characteristics of Electricity Supplied by Public Distribution Systems”EN50160 “公共配电系统所供电力的电压特征”EN50160 does not mand
26、ate IEC-61000-4-30 measurement techniques, but it is consistentEN50160标准对IEC-61000-4-30测量技术并没有要求,但是一致的。Both standards are exerting strong influence worldwide!两个标准对全世界有不同凡响的影响!LuisIntroduction to 3 Phase Power Company Confidential 19 IEC61000-4-30IEC61000-4-30 Testing and Measurement Techniques for P
27、ower Quality Measurement Methods.IEC61000-4-30 “电能质量测量的测试和测量技术”Refers to other standards like IEC61000-4-7 (Harmonics) and IEC61000-4-15 (Flicker)引用了其它标准,如IEC61000-4-7 (谐波) 和 IEC61000-4-15 (闪变)Two classes of measurement performance 两种类型的测量性能Class A, precise, suitable for compliance test and solving
28、disputes in courtA类,精确,适用于兼容性测试和解决争议Class B for troubleshooting and statistics surveysB类,用于故障诊断和统计测量IEC61000In this presentation this symbol means IEC 6100-4-30 is the guiding force在本幻灯片中,该标志表示以在本幻灯片中,该标志表示以IEC 6100-4-30 为导向为导向The Fluke 430 Series meets many of the specs for class A and all specs fo
29、r Class B!Fluke 430 系列满足多数系列满足多数A类技术指标要求和全部的类技术指标要求和全部的B类技术指标要求!类技术指标要求!LuisIntroduction to 3 Phase Power Company Confidential 20 IEC 61000-4-30 DefinitionsIEC 61000-4-30的定义的定义 Power frequency 电源频率Magnitude of the supply voltage 电源电压的幅度Flicker闪变Supply-voltage dips and swells电源电压骤降和骤升Voltage interrup
30、tions 断电Transient voltages 瞬态电压Supply voltage unbalance电源电压失衡Voltage harmonics电压谐波Voltage interharmonics电压谐间波Mains signaling voltage on the supply voltage电源电压上的主信号电压Rapid voltage changes快速的电压变化Measurement of underdeviation and overdeviation parameters 欠偏离和过偏离参数的测量Current电流IEC61000LuisIntroduction to
31、 3 Phase Power Company Confidential 21 IEC61000-4-30 “Aggregation”IEC61000-4-30 “集合集合”Measurement aggregation over time intervals时间间隔上的测量集合时间间隔上的测量集合Basic measurement time interval is基本的测量时间间隔为 10-cycles for 50 Hz systems对50 Hz 的系统为10个周期 12-cycles for 60 Hz systems对60 Hz的系统为12个周期Measurement time int
32、ervals are aggregated over 3 different time intervals:测量时间间隔由3个不同的时间间隔组成: 3-s interval (150 cycles for 50 Hz nominal or 180 cycles for 60 Hz nominal), 3-s间隔(对于标称为50 Hz的电压为150个周期,对于标称为60 Hz的电压为180个周期) 10-min interval, 10-min间隔 2-h interval. 2-h间隔Many measurements like rms voltage and harmonics are si
33、mply averaged. Others, like, flicker, arent quite so simple.许多测量参数如rms电压和谐波是经过简单平均得到的。其它参数如闪变并没那么简单。IEC61000The uses 10 minute aggregation for voltage, harmonics, flicker checking in System Monitor Mode. Plt is a 2-hour measurement.Fluke 430 使用使用10分钟间隔在系统监控模式下进行电压、谐分钟间隔在系统监控模式下进行电压、谐波和闪变检查。波和闪变检查。Pl
34、t为为2小时间隔测量的。小时间隔测量的。LuisIntroduction to 3 Phase Power Company Confidential 22 IEC61000-4-30 “Flagging”IEC61000-4-30“标记标记”During dip, swell, or interruption, other parameters may be unreliable?在骤降、骤升或断电期间,其它参数是不是可能不可靠?Flagging concept avoids counting a single event more than once通过标记,避免了重复计算某一信号事件Fla
35、gging is only triggered by dips, swells, and interruptions.标记仅由骤降、骤升和断电事件触发Applicable for measurement of power frequency, voltage magnitude, flicker, supply voltage unbalance, voltage harmonics, voltage interharmonics.适用于频率、电压幅度、闪变、电源电压失衡、电压谐波、电压谐间波的测量A flagged value is indicated on the Fluke 430 by
36、 a small flag in the upper right of the display.被标志的值由Fluke 430 显示屏右上角的标志表示。IEC61000Luis Introduction to 3 Phase Power Company Confidential 23 The Fluke 430 SeriesFluke 430 系列系列The Fastest Way to Pinpoint Power Quality Problems诊断细微的电能质量问题的最快途径LuisIntroduction to 3 Phase Power Company Confidential 24
37、 Power To GoFull 3-phase measurement! 完整的3相测量! 4 voltage inputs three phases and neutral. 4 current inputs allow measurements on three phases and neutral. 4个电压输入:三个相电压和零线电压。4个电流输入,可以测量三个相电流和零线电流。Runs for over 7 hours on NiMH batteries or runs on line power. Take it anywhere. 在由镍氢电池供电时,可使用7个小时以上;也可以由
38、市电供电。可以拿到任何地方进行测量。Includes everything you need to get down to work: voltage clips and leads, current clamps, and carrying case包括测量所需的一切功能:电压夹子和测试线、电流钳和便携包Fluke 434 includes FlukeView Software and interface cableFluke 434 包括FlukeView软件和接口电缆LuisIntroduction to 3 Phase Power Company Confidential 25 See
39、 What Youve Been Missing可以得到的新功能可以得到的新功能High resolution, color LCD for viewing multiple parameters and multiple phases simultaneously.高分辨率、彩色LCD,可以同时观察多个参数和多个相信号。Select from Industry Standard color coding or Choose your own. Lets you easily correlate connections and readings可以选择工业标准的色标,或自己选择颜色。可以方便地
40、正确连接和度数。LuisIntroduction to 3 Phase Power Company Confidential 26 Get Answers Fast!答案就是:快!答案就是:快!Fast-update, high-resolution scope display shows voltage and current waveforms for all three phases and neutral.快速刷新、高分辨率的示波器显示全部三个相信号和零线信号的电压和电流波形。Toggle to phasor display at any time for a quick check
41、of phase sequence.在任何时候都可以切换到矢量显示,快速检查相序。LuisIntroduction to 3 Phase Power Company Confidential 27 All Basic Measurements全部的基本测量全部的基本测量RMS and peak voltage, RMS and peak current, crest factor for all phases and neutralRMS和峰值电压、RMS和峰值电流、所有相信号和零线信号的波峰因数Frequency频率Watts, VA, VARs瓦特、伏安、乏Power Factor and
42、 displacement power factor功率因数和位移功率因数LuisIntroduction to 3 Phase Power Company Confidential 28 Auto Trending自动趋势绘图自动趋势绘图Automatic trending starts in the background when you select V-A-Hz, Power, or Harmonics. 当选择了V-A-Hz、功率或谐波功能时,则在后台启动自动趋势绘图功能Switch between numeric readings and trends without losing
43、 data.在数字读数和趋势绘图之间进行切换,而不会丢失数据 The Fluke 430 records every reading you see on the tables Fluke 430 记录在表中显示的所有读数LuisIntroduction to 3 Phase Power Company Confidential 29 Detailed Dips (Sags) & Swells细微的骤降和骤升信号细微的骤降和骤升信号Capture up to 100 dips or swells with 1/2 cycle visibility. 可以捕获100个1/2周期可见度的骤降和骤升
44、事件View data as graphs or as a list of events可以按事件的图表或清单观察数据Events are defined by EN50160 or by limits you set yourself事件可以由EN50160标准定义或用户设定的限制定义Dips and swells are captured per IEC 61000-4-30遵循IEC 61000-4-30标准捕获骤降和骤升事件LuisIntroduction to 3 Phase Power Company Confidential 30 System Monitor系统监控系统监控Sy
45、stemMonitor系统监控器How often is your rms voltage out of spec? rms电压超出技术指标的频率如何?How often is it distorted? 电压失真的频率如何? Get an overview of critical power events at a glance.初步了解严重的电能事件。EN50160 specifies limits for how often voltage events can occur. The Fluke 430 allows you to determine at a glance how often voltage is within user-adjustable tolerances. Drill down to see detailed trends behind the summary.Store up to 4 custom limit templates in the instrumentEN50160 标准规定了电压事件可以发生的频率。 利用Fluke 430,用户可以初步确定电压在可以调整的容差之内的频率。在初步了解的基础上,仔细观察详细的趋势。在设备中可以保存多达4组用户限制模板。结束结束