Transcription

Power Factor CorrectionSolutions & ApplicationsRick OrmanAmericas Sales ManagerPower Factor Correction/SurgeProtection/Power Conditioning 2012 Eaton Corporation. All rights reserved.

Power factor definition Power factor is theratio between the“real” power and the“apparent” power of anelectrical systemkVAkVArφkW “Real” power working power kW “Apparent” power Volts x Amps kVA “Reactive” power magnetizing power kVAR2 2012 Eaton Corporation. All rights reserved.2

What is a VAR? Active power, also called real power, ismeasured in Watts or kW and performs UsefulWork Electrical equipment like motors andtransformers require reactive power create aMagnetic Field and allow work to beperformed. This reactive power is called volt-amperesreactive or VAR’s Reactive power is measured in vars or kvars Total apparent power is called volt-amperesand is measured in VA or kVA3 2012 Eaton Corporation. All rights reserved.3

Somebody has to pay for capacity and lossesWasted Capacity(VAR’s)CapacityUseful Work(kVA)(Watts)5 2012 Eaton Corporation. All rights reserved.5

Typical Sources of Low Power Factor Reactive power is required by many loads toprovide magnetizing current for: Motors Power transformers Welding machines Electric arc furnaces Inductors Lighting ballasts6 2012 Eaton Corporation. All rights reserved.6

Utility must generate, transmit, anddistribute active AND reactive power7 2012 Eaton Corporation. All rights reserved.7

If reactive power could come from anothersource – utility can reduce 2012 Eaton Corporation. All rights reserved.8

What are these magical capacitors? 2012 Eaton Corporation. All rights reserved.10

What are these magical capacitors? 2012 Eaton Corporation. All rights reserved.11

What are these magical capacitors?Gas Pressure 2012 Eaton Corporation. All rights reserved.12

What are these magical capacitors? 2012 Eaton Corporation. All rights reserved.13

Why Consider PFC?PF correction provides many benefits: Primary Benefit: Reduced electric utility bill if there is a penalty Other Benefits: Increased system capacity (generators, cables, transformers) Reduced losses in transformers and cables Improved voltage regulation Greening the power system14 2012 Eaton Corporation. All rights reserved.14

Where do PF charges appear on a bill? Explicit Power Factor Penalty Power Factor Adjustment Power Factor Multiplier Reactive Demand Charge Calculated Demand Billed Demand15 2012 Eaton Corporation. All rights reserved.15

Escalation in Electrical Energy CostIndustrial Electrical Energy Cost by Year6.5Price/KWH (cents) Electrical Energy costhas increased nearly50% over the last 10years The rate of increasehas accelerated in thepast few years If your penalty is KWrelated, such as PFmultiplier applied to KWDemand, your penaltyamounts will track withEnergy Cost.65.554.541997 1998 1999 2000 2001 2002 2003 2004 2005 2006YearSource Energy Information Administration16 2012 Eaton Corporation. All rights reserved.16

Typical Uncorrected Power FactorIndustryPercent Uncorrected PFBrewery76-80Cement80-85Chemical65-75Coal -80Forge70-80Hospital75-80Machine manufacturing60-65Metal working65-70Office building80-90Oil-field pumping40-60Paint rks65-80Textile65-7517Source: IEEE Std 141-1993 (IEEERed Book)Low PF typically results fromunloaded or lightly loaded motorsUnloaded motor – PF .20Loaded motor – “rated PF” .85 2012 Eaton Corporation. All rights reserved.17

Example: Improving PFPower Factor 0.80125 kVA125 kVA100 kW100 kW150 A150 A75 kvar125 HP18 2012 Eaton Corporation. All rights reserved.18

Example: Improving PF Cont.Power Factor0.80 0.97103 kVA100 kW125 kVA100 kW124 A25 kvar153 A75 kvar125 HP1950 kvar 2012 Eaton Corporation. All rights reserved.19

Cost savings due to increased capacity Correcting poor powerfactor can significantlyreduce the load ontransformers andconductors and allowfor facility expansion Transformers are ratedby kVA and must besized accordingly20 2012 Eaton Corporation. All rights reserved.20

Effect of LocationR1ResistiveLoadR2MotorLoadPlace here for line lossreduction and voltageimprovementPlace here for utility PF penaltyPlace here for utility PF penalty(utility owned transformer)orPlace here to reduce losses intransformer or free capacity21 2012 Eaton Corporation. All rights reserved.21

Power Factor Correction – Lab Testing15 kVAR Caps18-pulse VFD, 75HPReactors75 kvaisolation 2012 Eaton Corporation. All rights reserved.22

Power Factor Correction – No VAPowerFactor026912169960.72153045607590105 2012 Eaton Corporation. All rights reserved.23

Power Factor Correction – 15 7590105 2012 Eaton Corporation. All rights reserved.24

Power Factor Correction – 30 0070800.8745607590105 2012 Eaton Corporation. All rights reserved.25

Power Factor Correction – 45 0070800.87452719270740.94607590105 2012 Eaton Corporation. All rights reserved.26

Power Factor Correction – 60 0070800.87452719270740.94602728870710.987590105 2012 Eaton Corporation. All rights reserved.27

Power Factor Correction – 75 00.9990105 2012 Eaton Corporation. All rights reserved.28

Power Factor Correction – 90 00.99902748970730.95 (1.05)105 2012 Eaton Corporation. All rights reserved.29

Power Factor Correction – 105 00.99902748970730.95 (1.05)1052769570790.89 (1.11) 2012 Eaton Corporation. All rights reserved.30

Power Factor Correction – No VAPowerFactor026912169960.72153045607590105 2012 Eaton Corporation. All rights reserved.31

Power Factor Correction – 15 7590105 2012 Eaton Corporation. All rights reserved.32

Power Factor Correction – 30 0070800.8745607590105 2012 Eaton Corporation. All rights reserved.33

Power Factor Correction – 45 0070800.87452719270740.94607590105 2012 Eaton Corporation. All rights reserved.34

Power Factor Correction – 60 0070800.87452719270740.94602728870710.987590105 2012 Eaton Corporation. All rights reserved.35

Power Factor Correction – 75 00.9990105 2012 Eaton Corporation. All rights reserved.36

Power Factor Correction – 90 00.99902748970730.95 (1.05)105 2012 Eaton Corporation. All rights reserved.37

Power Factor Correction – 105 00.99902748970730.95 (1.05)1052769570790.89 (1.11) 2012 Eaton Corporation. All rights reserved.38

On-Site PFCDemonstrationPower Factor Demonstration Unit – Designed to show phasedisplacement, system capacity increase, and dispel less thanreputable companies claiming 30-40% kW savings from capacitors! 2007 Eaton Corporation. All rights reserved.

Power Factor Defined –IEEE Emerald BookIEEE Std 1100-2005 Power Factor (displacement): The displacement component of power factor The ratio of the active power of the fundamentalwave (in watts) to the apparent power of thefundamental wave (in volt-amperes) Power Factor (total):kwpf -------kva The ratio of the total power input (in watts) to thetotal volt-ampere input.NOTE: This definition includes the effect of harmoniccomponents of currents and voltage and the effect of phasedisplacement between current and voltage. 2012 Eaton Corporation. All rights reserved.40

Power Factor ‘True’ EquationReference: Dr. Mack Grady, University of Texas at Austin, Proc of the EPRI Power Quality Issues & OpportunitiesConference (PQA ‘93), San Diego, CA, November 1993.For more info: http://users.ece.utexas.edu/ grady/POWERFAC.pdf41 2012 Eaton Corporation. All rights reserved.41

Two Types of Electrical Loads Linear NDUCTIONMOTORSVARIABLEFREQUENCYDRIVES42 2012 Eaton Corporation. All rights reserved.BALLASTSFLUORESCENT &HID LIGHTING42

Linear Loads Draw Power LinearlyVoltage Electrical voltage andcurrent “ebbs and flows”from plus to minus 60times per second. Voltage and Currentfollow the same rhythmperfectly in a linear load Current1/60THSEC.43 2012 Eaton Corporation. All rights reserved.43

Non-Linear Loads Draw Power Unevenly Current is drawn in short“gulps” or pulses.Current Voltage and Currentwaveforms are irregular anddon’t match – waveformsare said to be“DISTORTED”Voltage1/60TH NON-LINEAR LOADSPRODUCE HARMONICS Harmonics cause misoperation of equipment andWASTE ENERGY.44SEC. 2012 Eaton Corporation. All rights reserved.44

Distortive Power Factor 2012 Eaton Corporation. All rights reserved.45

Harmonic Resonance Capacitors not only supply reactive power to the loads in anelectrical distribution system they also change theresonance frequency of the system. Capacitors are also a “sink” for harmonic currents present ina system (series resonance). When the resonance frequency of a system with PFcorrection capacitors is close to the frequency of a harmoniccurrent generating load parallel resonance can occur.46

Why talk about - Harmonic ResonanceThe “Self Correcting”Problem- Blown Fuses- Failed Capacitors- Damaged Transformer 2012 Eaton Corporation. All rights reserved.47

Parallel Resonance The parallel combination of impedance is:X EQUIVALENT jX L ( j ) X CjX L ( j ) X C Since XL and XC have opposite signs, the denominator can equalzero if XL XC. In reality, the only limiting factor is the difference inresistance between the capacitor and reactor.Frequency Scan100000Impedance in Ohms10000XCXLHarmonic 1140126013801500Frequency in HzEquivalent Parallel Resonant Circuit48Frequency Scan for Parallel Resonant Circuit

Parallel ResonancehR MVASCMVARCAPXs1000 kVA5.75%480 V500 HP200 HPVSD49600 kVAR

Parallel Resonance – the ProblemZ At 420Hz (the 7th harmonic) theZ (impedance) of the circuit increasesfrom around 80 ohms to 10,000 ohms125 times increase!Subsequently, harmonic voltageIncreases 125 times!Solution? Make sure you perform calculation Purchase Power Factor caps with detuned anti-resonance filter Use capacitor-less solutions (HCU & others) 2012 Eaton Corporation. All rights reserved.50

Series ResonanceThe series combination of impedance is:X EQUIVALENT jX L ( j ) X CSince XL and XC have opposite signs, the summation can equal zeroif XL XC. In reality, the only limiting factor is the difference inresistance between the capacitor and reactor.Frequency ScanXLHarmonic CurrentSourceImpedance in Ohms10001001010.1XCEquivalent Series Resonant 00Frequency in HzFrequency Scan for Series Resonant Circuit

Expected HarmonicsSourceTypical Harmonics*6 Pulse Drive/Rectifier5, 7, 11, 13, 17, 19 12 Pulse Drive /Rectifier11, 13, 23, 25 18 Pulse Drive17, 19, 35, 37 Switch-Mode Power Supply 3, 5, 7, 9, 11, 13 Fluorescent Lights3, 5, 7, 9, 11, 13 Arcing Devices2, 3, 4, 5, 7.Transformer Energization2, 3, 4* Generally, magnitude decreases as harmonic order increasesH NP /-1i.e. 6 Pulse Drive - 5, 7, 11, 13, 17, 19, 52 2012 Eaton Corporation. All rights reserved.52

Harmonic Resonance - Solutions1. Change the method of kvar compensation (harmonicfilter, active filter, etc.)2. Change the size of the capacitor bank to overcompensate or under-compensate for the required kvarand live with the ramifications (i.e. overvoltage or PFpenalty).Natural System frequency of oscillation typically at 5th to 13th harmonic53 2012 Eaton Corporation. All rights reserved.53

What type of PFC solution? Capacitors (standard/harmonically hardened) Harmonic Filters (Tuned or De-tuned) Active Filters LV or MV Fixed or Switched (contactor or thyristor) Active harmonic filter (PF and harmonic control)CostCapacitors Hardened Capacitors54Harmonic Filters Active Filters 2012 Eaton Corporation. All rights reserved.54

Capacitor SelectionCapacitor selection issues (besides size) Utility penalties Installed cost, payback of equipment, and NPV Load variability Voltage regulation Load requirements (Speed of changing PF) Harmonic resonance55 2012 Eaton Corporation. All rights reserved.55

Application Example – At the LoadAt a motorGroup of MotorsR1R2Group of Motors w/harmonicsResistiveLoadMotorLoadVariable LoadEaton UnipumpVariable SystemVariable System w/harmonicsRapidly changingloadAdvantages Auto-regulating, comes on and off with loadCapacitor matched with load – reduces concernof overcorrectionRelatively small in size – easy to locate, noadditional distribution equipment requiredElectronic VARInjector MV at a motorWhen to UseMV variable load Facility load fluctuatesMany anticipated changes to plant system andloads 2012 Eaton Corporation. All rights reserved.57

Application Example – Group of LoadsAt a motorGroup of MotorsR1R2Group of Motors w/harmonicsResistiveLoadMotorLoadVariable LoadEaton UnipakVariable SystemVariable System w/harmonicsRapidly changingloadElectronic VARInjectorMV at a motorMV variable loadWhen to use Facility load is relatively constant – 24/7/365 Few anticipated changes to plant system &loadsConsiderations Possibility of “over-correcting” (leadingpower factor, increases current)Overvoltage can occur if load drops 2012 Eaton Corporation. All rights reserved.58

Application Example –Group of Harmonic LoadsAt a motorGroup of MotorsR1R2Group of Motors w/harmonicsHarmonicMotor LoadEaton Unipak FilterVariable LoadVariable SystemVariable System w/harmonicsRapidly changingloadResistiveLoadWhen to use Facility load is relatively constant – 24/7/365 Few anticipated changes to plant system &loadsCapacitors protected from harmonicsthrough the use of a detuned, antiresonance filter / reactors Electronic VARInjectorMV at a motorConsiderationsMV variable load Possibility of “over-correcting” (leadingpower factor, increases current)Overvoltage can occur if load drops 2012 Eaton Corporation. All rights reserved.59

Application Example – Variable LoadAt a motorGroup of MotorsR1R2Group of Motors w/harmonicsMotor LoadEaton AutoVAR 300Variable LoadVariable SystemVariable System w/harmonicsRapidly changingloadElectronic VARInjectorResistiveLoadAdvantages Single installationLoad is monitored and brings individualcapacitors in / out as required to meetpower factor target valueWall mountedWhen to useMV at a motorMV variable load When load flexibility is requiredFacility loads turned off at nightFuture load expected to change 2012 Eaton Corporation. All rights reserved.60

Application Example – Variable SystemAt a motorGroup of MotorsR1R2Group of Motors w/harmonicsMotor LoadEaton AutoVAR 600Variable LoadVariable SystemVariable System w/harmonicsRapidly changingloadElectronic VARInjectorResistiveLoadAdvantages Single installationSystem is monitored and brings individualcapacitors in / out as required to meetpower factor target valueFloor mountWhen to useMV at a motorMV variable load When system flexibility is requiredFacility loads turned off at nightFuture load expected to change 2012 Eaton Corporation. All rights reserved.61

Application Example – Variable Systemwith harmonicsAt a motorGroup of MotorsR1R2Group of Motors w/harmonicsHarmonicMotor LoadEaton AutoVAR 600 FilterVariable LoadVariable SystemVariable System w/harmonicsRapidly changingloadResistiveLoadAdvantages Single floor mount installationSystem is monitored and bringsindividual capacitors in / out asrequired to meetpower factor target valueFloor mountElectronic VARInjector MV at a motorWhen to useMV variable load When system flexibility is requiredFacility loads turned off at nightFuture load expected to change 2012 Eaton Corporation. All rights reserved.62

Application Example – Rapidly ChangingLoadAt a motorGroup of MotorsR1R2Group of Motors w/harmonicsEaton Fast Transient FreeVariable LoadVariable SystemVariable System w/harmonicsRapidly r LoadAdvantages Switches at zero-crossing – no transientsCan correct Power Factor within:FTA Model – 3 to 4 sFTE Model – 5 to 20 msIncludes detuned, anti-resonancefilteringElectronic VARInjector MV at a motorWhen to useMV variable load Rock crushing or other rapidly changingloads that require power factor correction 2012 Eaton Corporation. All rights reserved.63

Application Example – Electronic VARInjectorAt a motorGroup of MotorsR1R2Group of Motors w/harmonicsElectronic VAR InjectorVariable LoadVariable SystemVariable System w/harmonicsRapidly changingloadElectronic VARInjectorMV at a motorResistiveLoadRapidchangingHarmonicMotor LoadAdvantages Power electronics – no capacitorsProvide VARs in non-standard harmonicenvironment2 cycle responseWhen to use Most demanding of all electricalenvironments (208-480V, 45 to 65 Hz)MV variable load 2012 Eaton Corporation. All rights reserved.64

Application Example – Medium Voltage atMotorAt a motorMotor LoadGroup of MotorsR2Group of Motors w/harmonicsResistiveLoadMotor LoadVariable LoadVariable SystemEaton MV UniVAR & MVVariable System w/harmonicsRapidly changingloadElectronic VARInjectorMV at a motorAdvantages Designed for industrial and commercialpower systems with their own substationsUniVAR XV: 2.4kV to 4.8kVUniVAR MV: 6.6kV to 13.8kVAvailable from 25 kVAR to 900 kVARMV variable load 2012 Eaton Corporation. All rights reserved.65

Application Example – Medium VoltageVariable loadAt a motorGroup of MotorsR2Group of Motors w/harmonicsResistiveLoadMotor LoadVariable LoadVariable SystemMetal-Enclosed MVVariable System w/harmonicsRapidly changingloadElectronic VARInjectorMV at a motorMV variable loadAdvantages Built in detuning, antiresonance filtering to protectthe capacitorsUp to 15 MVAR ofcompensationTop of Bottom Cable EntryUp to 12 automatic switchedcapacitor/reactor stages 2012 Eaton Corporation. All rights reserved.66

Power Quality Experience Center and Lab Overview of Lab and Capabilities Purpose To demonstrate and Test PQProblems and Solutions Power Quality solutions, especiallyharmonic solutions, are difficult tounderstand Demystify solutions – mis-information and confusion regarding PQ andenergy savings Equipment (Harmonic Related) 18 Pulse Drives Passive (Fixed) Filters HMT’s Passive (Switched) Filters Active Filters Active Rectifier (UPS) Broadband Filters /Electrical/ServicesSupport/Experience/index.htm – Simply search on Google for Eaton Experience Center67 2012 Eaton Corporation. All rights reserved.67

Eaton Power Factor Correction ToolTM - Resonance68 2012 Eaton Corporation. All rights reserved.68

PFC Tools – PFC Selection Chart 2012 Eaton Corporation. All rights reserved.69

PFC Literature – Design it Right GuideApplication Examples 2012 Eaton Corporation. All rights reserved.70

PFC Literature – Design it Right GuideSizing Charts 2012 Eaton Corporation. All rights reserved.71

PFC Literature – Technical Data –LV & MV 2012 Eaton Corporation. All rights reserved.72

PFC Literature – Customer Survey Sheet 2012 Eaton Corporation. All rights reserved.73

What to do next? Contact Eaton – GSF, ManufacturingRepresentative, Technical Resource Center(TRC) and our website Website: www.eaton.com/pfc Calculators, data sheets, presentations, site surveys TRC: 800-809-2772, Option 4, Option 2 Answered during business hours Eastern Time. Typicalresponse turnaround 24 hours or less. 2012 Eaton Corporation. All rights reserved.74

The Hidden ThreatQuick introduction to Surge Protection 2012 Eaton Corporation. All rights reserved.

Voltage Transients (Surge)DefinitionA high rising voltagecondition which lasts 2 msor less and can produceup to 20 kV! 2012 Eaton Corporation. All rights reserved.76

What is the Threat? Equipment damage Insulation breakdown Premature aging Process interruption Data loss 2012 Eaton Corporation. All rights reserved.77

What are the Causes?80% Internal Load switching Short circuits ManufacturingEquipment VS Drives20% External Lightning Capacitorswitching Utility loadswitching 2012 Eaton Corporation. All rights reserved.78

SPD DesignDesign Tips 2012 Eaton Corporation. All rights reserved.

Independent tests confirm betterperformance with integrated SPDsGoodSide MountGood let-thoughif leads are short.BetterBestWiredConnectionDirect BusConnectedBetter than sidemount.Best Protection 2012 Eaton Corporation. All rights reserved.80

Performance/Application - Affect of LeadLength on Let-through VoltageIEEE C1 (6000V, 3000A) WaveformAdditional Let Through Voltage(Additional to device Let Through)90014 AWG10 AWG4 AWG80070060050040030020010003 Feet Loose Wire3 Feet Twisted Wire1 Foot Twisted Wire 2012 Eaton Corporation. All rights reserved.81

Nameplate Data - Peak surge currentrating The peak surge current isa predictor of how long anSPD will last in a givenenvironment The higher the kA, thelonger the life of the MOVs Similar to the tread on atire The thicker the tread, thelonger the tire will last 2012 Eaton Corporation. All rights reserved.82

IEEE Emerald Book factsPanelboards are available that contain integrallymounted SPDs that minimize the length of the SPDconductors, thus optimizing the effectiveness ofthe device.“Why is my SPD NotProtecting Me?” 2012 Eaton Corporation. All rights reserved.20 feet of conduit83

Biggest News in Surge Protection2014 NEC Article 700.8requires surge protection foremergency circuits. Eaton hasproduced Sales AidSA158003EN to describe thiscode change and impact. Thedocument is available onliterature fulfillment and thewebsite. 2012 Eaton Corporation. All rights reserved.84

2012 Eaton Corporation. All rights reserved.85

Power factor definition "Real" power working power kW "Apparent" power Volts x Amps kVA "Reactive" power magnetizing power kVAR φ. kVA . kVAr . kW Power factor is the ratio between the "real" power and the "apparent" power of an electrical system