Risks and Opportunities of ReactivePower Compensators in Environ-ments with HarmonicsStefan FassbinderDKI German Copper In...
The German Copper Institute, DKI,is the central information andadvisory service dealing with alluses of copper and copper ...
Everybody knows reactive power
But what do we really mean by it?
But what do we really mean by it?Generation of leading reactive power = Absorption of lagging reactive powerGeneration of ...
But what do we really mean by it?Reactive power is the share of the power which does notcontribute to the transmission of ...
So what then is reactive energy?
If the voltage is sinusoidal, thecurrent is sinusoidal too – right?-350V-300V-250V-200V-150V-100V-50V0V50V100V150V200V250V...
And what about other voltage-current profiles?-350V-300V-250V-200V-150V-100V-50V0V50V100V150V200V250V300V350V0ms 5ms 10ms ...
E. g. when a square-wave voltage with smallconductive angle is applied to an inductor?-100V-80V-60V-40V-20V0V20V40V60V80V1...
Or when a triangular voltage with a small conductiveangle is applied to a capacitor?-100V-80V-60V-40V-20V0V20V40V60V80V100...
Or when a triangular current profile with a smallconductive angle is driven through a capacitor?-100A-80A-60A-40A-20A0A20A...
But fortunately:-400 %-300 %-200 %-100 %0 %100 %200 %300 %400 %0ms 5ms 10ms 15ms 20msti/Iitot i1i3 i5i7 i9i11 i13i15 i17Ev...
Harmonic reactive power
Currents are no longer sinusoidalVoltages are no longer sinusoidalVoltages and currents contain higher-frequencyconstituen...
fLXL π2=fCXCπ21=2222)( CLCuSCu XXRXRZ −+=+=fCfLXXX CLSππ212 −=−=The real-life behaviour
Why detune?To prevent the occurrence oftransformer resonances, for example.
Why detune?To prevent the occurrence oftransformer resonances, for example.
Why detune?To prevent the occurrence oftransformer resonances, for example.
Why detune?To prevent the occurrence oftransformer resonances, for example.
So it’s quite natural to ask:What is harmonic reactive power?Well, it all depends on how you seethings and how you measure...
Detuned Static VAR Compensator (SVC)0Ω2Ω4Ω6Ω8Ω10Ω12Ω14Ω16Ω18Ω20Ω100Hz 200Hz 300Hz 400Hz 500Hz 600HzfZ-90°-75°-60°-45°-30°-...
Detuned Static VAR Compensator (SVC)0Ω2Ω4Ω6Ω8Ω10Ω12Ω14Ω16Ω18Ω20Ω100Hz 200Hz 300Hz 400Hz 500Hz 600HzfZ-90°-75°-60°-45°-30°-...
Parallel resonant bandpass filter(‘rejection circuit’)0Ω20Ω40Ω60Ω80Ω100Ω120Ω140Ω160Ω100Hz 200Hz 300Hz 400Hz 500Hz 600HzfZ-...
Parallel resonant bandpass filter(‘rejection circuit’)0Ω20Ω40Ω60Ω80Ω100Ω120Ω140Ω160Ω100Hz 200Hz 300Hz 400Hz 500Hz 600HzfZ-...
Parallel resonant bandpass filter(‘rejection circuit’)0Ω20Ω40Ω60Ω80Ω100Ω120Ω140Ω160Ω100Hz 200Hz 300Hz 400Hz 500Hz 600HzfZ-...
Trying to save money byTrying to save money byskimping onskimping on coppercopperusually turns out to be a costlymistake. ...
VArWWVAPSQ 146)858()160( 2222≈+−=−=VAAVS 16067,0*230 ==Example: a 58-W tube with a low-loss ballast Example: an 11-Wtube w...
or in the so-called ‘duo’or lead-lagconfigurationeither in aconventionalparallelconfigurationCompensation is best done r...
Two 58W lamps with two ballasts and one capacitor0Ω50Ω100Ω150Ω200Ω250Ω300Ω350Ω400Ω450Ω500Ω40Hz 50Hz 60Hz 70Hz 80Hz 90HzfZX...
Two 58W lamps with two ballasts and one capacitor0Ω50Ω100Ω150Ω200Ω250Ω300Ω350Ω400Ω450Ω500Ω40Hz 50Hz 60Hz 70Hz 80Hz 90HzfZX...
58W lamp with a class B1 magnetic ballast-350V-300V-250V-200V-150V-100V-50V0V50V100V150V200V250V300V350V0ms 5ms 10ms 15ms ...
Two 58W lamps, one in series with a 5.3 µFcapacitor-350V-300V-250V-200V-150V-100V-50V0V50V100V150V200V250V300V350V0ms 5ms ...
Two 58W lamps, one in series with a 5.3 µFcapacitor-350V-300V-250V-200V-150V-100V-50V0V50V100V150V200V250V300V350V0ms 5ms ...
Two 58W lamps, one with reduced 4.6µF capacitor-350V-300V-250V-200V-150V-100V-50V0V50V100V150V200V250V300V350V0ms 5ms 10ms...
Possible overloading of capacitors attacheddirectly to the mains due tohigher frequenciespresent in thesupply systemDealin...
Risk with parallel compensation:Higher frequencies cause capacitor to overload, as shownhere for an 11W fluorescent lamp w...
A reliable concept:Conventional power factorcompensation system detunedto draw off the strongest harmonics
Dealing with side effectsof the second kind:Rejection circuits ensurethat ripple-controlsignals don’t get lost
Cleaning effect of a 250Hz filterrecorded in a residential areain Germany, June 30, 2002, 14:30
The advantageous dualpassive filtercan reduce e. g. the harmoniccontent of a dimmer current substantially
Well, this was just a modelHere come three real-life examplesof detuned static var compensators withthree different rating...
Dimensioning a twin filter made of 2 acceptor circuits operating in parallel – input valuesHarmonics in themains voltage:R...
Behaviour of said dual filter0Ω1Ω2Ω3Ω4Ω5Ω0Hz 450Hz 900Hz 1350HzfZ-90°-75°-60°-45°-30°-15°0°15°30°45°60°75°90°φZ5Z7Ztotφ5φ7...
Complementary behaviourCCCurrent is proportional to therate of change of voltage.LLVoltage is proportional to therate of c...
Series LC resonantcircuit (‘acceptorcircuit’)Parallel LCresonant circuit(‘rejector circuit’)Switch on anytime(soft switchi...
gave a total of 3 million Euros from within the frameworkgave a total of 3 million Euros from within the frameworkof their...
The European Union3 projects out of about 4000 awarded – oneof them was:
gave a total of 3 million Euros from within the frameworkgave a total of 3 million Euros from within the frameworkof their...
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Risks and Opportunities of Reactive Power Compensators in Environments with Harmonics

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With increasing use of electronic equipment fed from low voltage distribution systems, problems have arisen in recent years from the harmonic currents dissipated by such equipment. One of the problems is that capacitors directly connected to the mains voltage, such as those in static var compensators, can be overloaded on account of their lower reactance to higher frequencies. The common means of avoiding this is to use de-tuning, i. e. connecting each capacitor in series with a small inductance. While this actually does solve the problem, the dimensioning of this inductance bears both the risk of causing new problems and the chance of mitigating the level of harmonics in the LV system. This presentation wants to give guidance how to dimension a static var compensator in a way to avoid the problems and at the same time use the device as a harmonics filter.

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Risks and Opportunities of Reactive Power Compensators in Environments with Harmonics

  1. 1. Risks and Opportunities of ReactivePower Compensators in Environ-ments with HarmonicsStefan FassbinderDKI German Copper InstituteAm Bonneshof 5D-40474 DüsseldorfTel.: +49 / 211 / 4796-323Fax: +49 / 211 / 4796-310sfassbinder@kupferinstitut.dewww.kupferinstitut.de
  2. 2. The German Copper Institute, DKI,is the central information andadvisory service dealing with alluses of copper and copper alloys.We offer our services to:Commercial companiesThe skilled tradesIndustryResearch institutesUniversitiesArtists and craftsmenStudentsPrivate individualsWe can be contacted by:postphonefaxe-mailinternetonline database, orpersonally
  3. 3. Everybody knows reactive power
  4. 4. But what do we really mean by it?
  5. 5. But what do we really mean by it?Generation of leading reactive power = Absorption of lagging reactive powerGeneration of lagging reactive power = Absorption of leading reactive power
  6. 6. But what do we really mean by it?Reactive power is the share of the power which does notcontribute to the transmission of energy (work)
  7. 7. So what then is reactive energy?
  8. 8. If the voltage is sinusoidal, thecurrent is sinusoidal too – right?-350V-300V-250V-200V-150V-100V-50V0V50V100V150V200V250V300V350V0ms 5ms 10ms 15ms 20mstu-20A-15A-10A-5A0A5A10A15A20AiSine voltageL current with sine voltageC current with sine voltageL = 55 mHC = 175 µFf = 50 Hzt)sin(*û)( ω=tu t)cos(*î)( ω−=tiLt)cos(*î)( ω=tiC
  9. 9. And what about other voltage-current profiles?-350V-300V-250V-200V-150V-100V-50V0V50V100V150V200V250V300V350V0ms 5ms 10ms 15ms 20mstu-20A-15A-10A-5A0A5A10A15A20AiSine voltageL current with sine voltageC current with sine voltageL = 55 mHC = 175 µFf = 50 Hzt)sin(*û)( ω=tu t)cos(*î)( ω−=tiLt)cos(*î)( ω=tiC
  10. 10. E. g. when a square-wave voltage with smallconductive angle is applied to an inductor?-100V-80V-60V-40V-20V0V20V40V60V80V100V0ms 5ms 10ms 15ms 20mstuL-100A-80A-60A-40A-20A0A20A40A60A80A100AiLRectangularvoltageL current withrectangularvoltageConductive angle = 30 %Peak value = 100 VL = 3 mHf = 50 Hz
  11. 11. Or when a triangular voltage with a small conductiveangle is applied to a capacitor?-100V-80V-60V-40V-20V0V20V40V60V80V100V0ms 5ms 10ms 15ms 20mstuC-100A-80A-60A-40A-20A0A20A40A60A80A100AiCTriangularvoltageC current withtriangularvoltageConductive angle = 30 %Peak value = 100 VC = 1500 µFf = 50 Hz
  12. 12. Or when a triangular current profile with a smallconductive angle is driven through a capacitor?-100A-80A-60A-40A-20A0A20A40A60A80A100A0ms 5ms 10ms 15ms 20mstiC-100V-80V-60V-40V-20V0V20V40V60V80V100VuCTriangular currentC voltage with triangular currentConductive angle = 75 %Peak value = 100 VC = 3750 µFf = 50 Hz
  13. 13. But fortunately:-400 %-300 %-200 %-100 %0 %100 %200 %300 %400 %0ms 5ms 10ms 15ms 20msti/Iitot i1i3 i5i7 i9i11 i13i15 i17Every periodic waveform can bewritten as the finite sum ofsinusoidal waves whosefrequencies are integer multiples ofthe fundamental frequency
  14. 14. Harmonic reactive power
  15. 15. Currents are no longer sinusoidalVoltages are no longer sinusoidalVoltages and currents contain higher-frequencyconstituentsRisk that capacitors willoverloadCapacitors can help toeliminate this highfrequency contaminationStatic var compensators in suchan environment – a threat and anopportunity!
  16. 16. fLXL π2=fCXCπ21=2222)( CLCuSCu XXRXRZ −+=+=fCfLXXX CLSππ212 −=−=The real-life behaviour
  17. 17. Why detune?To prevent the occurrence oftransformer resonances, for example.
  18. 18. Why detune?To prevent the occurrence oftransformer resonances, for example.
  19. 19. Why detune?To prevent the occurrence oftransformer resonances, for example.
  20. 20. Why detune?To prevent the occurrence oftransformer resonances, for example.
  21. 21. So it’s quite natural to ask:What is harmonic reactive power?Well, it all depends on how you seethings and how you measure them...
  22. 22. Detuned Static VAR Compensator (SVC)0Ω2Ω4Ω6Ω8Ω10Ω12Ω14Ω16Ω18Ω20Ω100Hz 200Hz 300Hz 400Hz 500Hz 600HzfZ-90°-75°-60°-45°-30°-15°0°15°30°45°60°75°90°φReactor reactanceCapacitor reactanceSerial impedancePhase angleRCu = 1 ΩL = 8 mHC = 50 µF
  23. 23. Detuned Static VAR Compensator (SVC)0Ω2Ω4Ω6Ω8Ω10Ω12Ω14Ω16Ω18Ω20Ω100Hz 200Hz 300Hz 400Hz 500Hz 600HzfZ-90°-75°-60°-45°-30°-15°0°15°30°45°60°75°90°φReactor reactanceCapacitor reactanceSerial impedancePhase angleRCu = 1 ΩL = 4 mHC = 100 µF
  24. 24. Parallel resonant bandpass filter(‘rejection circuit’)0Ω20Ω40Ω60Ω80Ω100Ω120Ω140Ω160Ω100Hz 200Hz 300Hz 400Hz 500Hz 600HzfZ-90°-75°-60°-45°-30°-15°0°15°30°45°60°75°90°φReactor reactanceCapacitor reactanceParallel impedacePhase angleRCu = 1 ΩL = 8 mHC = 50 µF
  25. 25. Parallel resonant bandpass filter(‘rejection circuit’)0Ω20Ω40Ω60Ω80Ω100Ω120Ω140Ω160Ω100Hz 200Hz 300Hz 400Hz 500Hz 600HzfZ-90°-75°-60°-45°-30°-15°0°15°30°45°60°75°90°φReactor reactanceCapacitor reactanceParallel impedacePhase angleRCu = 1 ΩL = 4 mHC = 100 µF
  26. 26. Parallel resonant bandpass filter(‘rejection circuit’)0Ω20Ω40Ω60Ω80Ω100Ω120Ω140Ω160Ω100Hz 200Hz 300Hz 400Hz 500Hz 600HzfZ-90°-75°-60°-45°-30°-15°0°15°30°45°60°75°90°φReactor reactanceCapacitor reactanceParallel impedacePhase angleR Cu = 0.25 ΩL = 8.00 mHC = 50.00 µF
  27. 27. Trying to save money byTrying to save money byskimping onskimping on coppercopperusually turns out to be a costlymistake. And in the case of power factor cor-rection circuits, you can end up paying twice!According to the experts at ElectroniconKondensatoren GmbH in Gera:‘Most customers aren’t even aware that byfocusing solely on cutting costs, the moneythey saved through reactive power com-pensation measures is lost via active powerlosses in the compensation circuit.’
  28. 28. VArWWVAPSQ 146)858()160( 2222≈+−=−=VAAVS 16067,0*230 ==Example: a 58-W tube with a low-loss ballast Example: an 11-Wtube with aconventionalmagnetic ballastFluorescent lamps with magnetic ballasts:A classic source of reactive power thatrequires compensation-350V-250V-150V-50V50V150V250V350V0ms 5ms 10ms 15ms 20mstu-1.0A-0.5A0.0A0.5A1.0AiSystems voltageLamp voltageCurrent
  29. 29. or in the so-called ‘duo’or lead-lagconfigurationeither in aconventionalparallelconfigurationCompensation is best done right at thesource – as is in fact often the case influorescent lamps –
  30. 30. Two 58W lamps with two ballasts and one capacitor0Ω50Ω100Ω150Ω200Ω250Ω300Ω350Ω400Ω450Ω500Ω40Hz 50Hz 60Hz 70Hz 80Hz 90HzfZX(L)X(C)Z(ser)CorrectlydimensionedRCu =13.8 ΩL =878 mHC = 5.7 µF22RLC )212(Z CuRfCfL +−=ππfCπ21XC =Fπ2XL =
  31. 31. Two 58W lamps with two ballasts and one capacitor0Ω50Ω100Ω150Ω200Ω250Ω300Ω350Ω400Ω450Ω500Ω40Hz 50Hz 60Hz 70Hz 80Hz 90HzfZX(L)X(C)Z(ser)RCu =13.8 ΩL =878 mHC = 6.8 µFDimensioning is 20% inerror: Reactance is 32% inerror!fCπ21XC =fLπ2XL =22RLC )212(Z CuRfCfL +−=ππ
  32. 32. 58W lamp with a class B1 magnetic ballast-350V-300V-250V-200V-150V-100V-50V0V50V100V150V200V250V300V350V0ms 5ms 10ms 15ms 20mstu-1,4A-1,2A-1,0A-0,8A-0,6A-0,4A-0,2A0,0A0,2A0,4A0,6A0,8A1,0A1,2A1,4AiUI(L)
  33. 33. Two 58W lamps, one in series with a 5.3 µFcapacitor-350V-300V-250V-200V-150V-100V-50V0V50V100V150V200V250V300V350V0ms 5ms 10ms 15ms 20mstu-1,4A-1,2A-1,0A-0,8A-0,6A-0,4A-0,2A0,0A0,2A0,4A0,6A0,8A1,0A1,2A1,4AiUI(L)I(C=5.3µF)
  34. 34. Two 58W lamps, one in series with a 5.3 µFcapacitor-350V-300V-250V-200V-150V-100V-50V0V50V100V150V200V250V300V350V0ms 5ms 10ms 15ms 20mstu-1,4A-1,2A-1,0A-0,8A-0,6A-0,4A-0,2A0,0A0,2A0,4A0,6A0,8A1,0A1,2A1,4AiUI(L)I(C=5.3µF)I(C+L)
  35. 35. Two 58W lamps, one with reduced 4.6µF capacitor-350V-300V-250V-200V-150V-100V-50V0V50V100V150V200V250V300V350V0ms 5ms 10ms 15ms 20mstu-1,4A-1,2A-1,0A-0,8A-0,6A-0,4A-0,2A0,0A0,2A0,4A0,6A0,8A1,0A1,2A1,4AiUI(L)I(C=4.6µF)I(tot)(C=4.6µF)
  36. 36. Possible overloading of capacitors attacheddirectly to the mains due tohigher frequenciespresent in thesupply systemDealing with side effectsof the first kind:Filter capacitor currentinto a PC power supplywhile switched of
  37. 37. Risk with parallel compensation:Higher frequencies cause capacitor to overload, as shownhere for an 11W fluorescent lamp with magnetic ballast
  38. 38. A reliable concept:Conventional power factorcompensation system detunedto draw off the strongest harmonics
  39. 39. Dealing with side effectsof the second kind:Rejection circuits ensurethat ripple-controlsignals don’t get lost
  40. 40. Cleaning effect of a 250Hz filterrecorded in a residential areain Germany, June 30, 2002, 14:30
  41. 41. The advantageous dualpassive filtercan reduce e. g. the harmoniccontent of a dimmer current substantially
  42. 42. Well, this was just a modelHere come three real-life examplesof detuned static var compensators withthree different ratings, actually built andsold by a specialized companyReactivepowerratingDetuningfactorReactorlosses perphaseI(in deltawiring)X C50 HzX L50 HzC L RCukVAr % W A Ω Ω µF mH mΩ10.0 7% 15.7 8.33 51.360 3.360 62.0 10.695 225.622.5 7% 24.3 18.75 22.827 1.493 139.4 4.753 69.267.4 7% 52.3 56.17 7.620 0.499 417.7 1.587 16.6The values are convincing, losses areminimal!
  43. 43. Dimensioning a twin filter made of 2 acceptor circuits operating in parallel – input valuesHarmonics in themains voltage:Ratings of your system and the filters:No. f Uf U 240.000 V Rated TRMS mains voltage1 50Hz 239.49V f 50.000 Hz Rated mains frequency2 100Hz 0.00V R5 16.600 mΩ Ohmic winding resistance of lower frequency reactor (usually tuned to or near the 5th harmonic)3 150Hz 12.00V L5 1.587 mH Inductance of lower frequency reactor (usually tuned to or near the 5th harmonic)4 200Hz 0.00V C5 417.700 µF Capacitance of lower frequency reactor (usually tuned to or near the 5th harmonic)5 250Hz 8.00V R7 16.600 mΩ Ohmic winding resistance of higher frequency reactor (usually tuned to or near the 7th harmonic)6 300Hz 0.00V L7 0.810 mH Inductance of higher frequency reactor (usually tuned to or near the 7th harmonic)7 350Hz 4.00V C7 213.112 µF Capacitance of higher frequency reactor (usually tuned to or near the 7th harmonic)8 400Hz 0.00V f 0(5) 195.479 Hz Resonance frequency of the 5th order filter9 450Hz 3.00V f 0(7) 383.138 Hz Resonance frequency of the 7th order filter10 500Hz 0.00V11 550Hz 2.50V12 600Hz 0.00V13 650Hz 2.00V14 700Hz 0.00V15 750Hz 1.50V16 800Hz 0.00V17 850Hz 1.00V18 900Hz 0.00V19 950Hz 0.50V20 1000Hz 0.00V21 1050Hz 0.00V22 1100Hz 0.00V23 1150Hz 0.00V24 1200Hz 0.00V25 1250Hz 0.00V26 1300Hz 0.00V27 1350Hz 0.00VXL-XCRCuZC5L5 URCu5C7L7RCu7A calculation template is available at:www.leonardo-energy.org/drupal/dimensioning-passive-filter-tool
  44. 44. Behaviour of said dual filter0Ω1Ω2Ω3Ω4Ω5Ω0Hz 450Hz 900Hz 1350HzfZ-90°-75°-60°-45°-30°-15°0°15°30°45°60°75°90°φZ5Z7Ztotφ5φ7φtot
  45. 45. Complementary behaviourCCCurrent is proportional to therate of change of voltage.LLVoltage is proportional to therate of change of current.Reactance decreases withincreasing frequency.Energy content proportionalto the square of the voltage.Large current spikes whenswitching on, unlessswitching occurs whenvoltage is passing throughzero.Reactance increases withincreasing frequency.Energy content proportionalto the square of the current.Large voltage spikes whenswitching off, unlessswitching occurs whencurrent is passing throughzero.
  46. 46. Series LC resonantcircuit (‘acceptorcircuit’)Parallel LCresonant circuit(‘rejector circuit’)Switch on anytime(soft switching)Zero-current switch-off(otherwise: hardswitching generatesvoltage transients)Zero-voltage switch-on(otherwise: hardswitching generatescurrent transients)Switch off anytime(soft switching)Complementary behaviour
  47. 47. gave a total of 3 million Euros from within the frameworkgave a total of 3 million Euros from within the frameworkof their LEONARDOof their LEONARDO programmeprogramme to establishto establish thethe European websiteEuropean websitedealing withdealing with allall aspects of power quality with the help of adequateaspects of power quality with the help of adequatepartners! Just go topartners! Just go towww.lpqi.orgwww.lpqi.orgfrom time to time and watch thefrom time to time and watch the Leonardo Power Quality InitiativeLeonardo Power Quality Initiativegrowing! We want to develop and provide vocational training mategrowing! We want to develop and provide vocational training material onrial onthe mitigation of power quality problems inthe mitigation of power quality problems in 11 languages!11 languages!We address all electrical experts working in the field: EngineerWe address all electrical experts working in the field: Engineers,s,handicraftsmen, building maintenance technicians, architecturalhandicraftsmen, building maintenance technicians, architectural andandplanning consultants as well as trainers and trainees.planning consultants as well as trainers and trainees.So long, we are 86 partners from Europe, North and South AmericaSo long, we are 86 partners from Europe, North and South America,,among them commercial companies, institutes, universities and 5among them commercial companies, institutes, universities and 5 nationalnationalcoppercopper centrescentres. Participation and contributions of further partners from. Participation and contributions of further partners fromindustry and academics is possible at any time and even desiredindustry and academics is possible at any time and even desired by theby theexisting project partners.existing project partners.Just give us a click!Just give us a click!www.lpqi.orgThe European Union
  48. 48. The European Union3 projects out of about 4000 awarded – oneof them was:
  49. 49. gave a total of 3 million Euros from within the frameworkgave a total of 3 million Euros from within the frameworkof their LEONARDOof their LEONARDO programmeprogramme to establishto establish thethe European websiteEuropean websitedealing withdealing with allall aspects of power quality with the help of adequateaspects of power quality with the help of adequatepartners! Just go topartners! Just go towww.lpqi.orgwww.lpqi.orgfrom time to time and watch thefrom time to time and watch the Leonardo Power Quality InitiativeLeonardo Power Quality Initiativegrowing! We want to develop and provide vocational training mategrowing! We want to develop and provide vocational training material onrial onthe mitigation of power quality problems inthe mitigation of power quality problems in 11 languages!11 languages!We address all electrical experts working in the field: EngineerWe address all electrical experts working in the field: Engineers,s,handicraftsmen, building maintenance technicians, architecturalhandicraftsmen, building maintenance technicians, architectural andandplanning consultants as well as trainers and trainees.planning consultants as well as trainers and trainees.So long, we are 86 partners from Europe, North and South AmericaSo long, we are 86 partners from Europe, North and South America,,among them commercial companies, institutes, universities and 5among them commercial companies, institutes, universities and 5 nationalnationalcoppercopper centrescentres. Participation and contributions of further partners from. Participation and contributions of further partners fromindustry and academics is possible at any time and even desiredindustry and academics is possible at any time and even desired by theby theexisting project partners.existing project partners.Just give us a click!Just give us a click!www.lpqi.orgThe European Union

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