1、Variable Speed DriveTechnology YORK MILLENNIUM VSD CHILLERSFranciscan HospitalSEM IncorporatedOne Valley BankMarch 11, 1999Todays Topics How chillers operate How VSD works Energy comparison Features and benefits Harmonics Application Experience Evaluating chiller performanceCentrifugal ChillerCentri
2、fugal ChillerOrificeSubcoolerCondenserDiffuser PlateImpellerFlooded EvaporatorPrerotation VanesMist EliminatorPressureEnthalpyPressure - Enthalpy ChartEvaporatorCompressorCondenserMetering DeviceRefrigerant rejects heat to atmosphereRefrigerant absorbs heat from loadPressureEnthalpyPressure - Enthal
3、py Chart9585 Cooling Tower4454Less than 1% of chiller run hours are at design full-load!331112258409617732706710678020040060080094-9084-8074-7064-6054-50Dry-bulb Temperature Bins (F) Annual Hours5055606570758085ECWT (F) Hartford Weather020040060080094-9084-8074-7064-6054-50Dry-bulb Temperature Bins
4、(F) Annual Hours5055606570758085ECWT (F) Hartford Weather331112258409617732706710678020040060080094-9084-8074-7064-6054-50Dry-bulb Temperature Bins (F) Annual Hours5055606570758085ECWT (F) Hartford Weather331112258732706710678020040060080094-9084-8074-7064-6054-50Dry-bulb Temperature Bins (F) Annual
5、 Hours5055606570758085ECWT (F) Hartford Weather331112258409617732706710678020040060080094-9084-8074-7064-6054-50Dry-bulb Temperature Bins (F) Annual Hours5055606570758085ECWT (F) Hartford Weather331112258409617732706710678020040060080094-9084-8074-7064-6054-50Dry-bulb Temperature Bins (F) Annual Hou
6、rs5055606570758085ECWT (F) Hartford Weather99.2%EvaporatorCompressorCondenserPressureEnthalpyHead PressureHead PressureEvaporatorCompressorCondenserPressureEnthalpyHead PressureEvaporatorCompressorCondenserPressureEnthalpyHead PressureHead PressureEvaporatorCompressorCondenserPressureEnthalpyHead Pr
7、essureHead PressureHead PressureEvaporatorCompressorCondenserPressureEnthalpyHead PressureEvaporatorCompressorCondenserPressureEnthalpyHead PressureHead PressureEvaporatorCompressorCondenserPressureEnthalpyHead PressureHead PressureFan Laws RPM CFM RPM 2 STATIC HEAD RPM 3 HPRPM vs HP% RPM%HP 100 100
8、 90 73 75 42 50 12How do we apply this to a chiller?Variable Speed DrivesWhat is Variable Speed?Car AnalogyPrerotation vanesElectricmotorConstant Speed Accelerator pegged to the floorConstant Speed Brake to slow down Accelerator pegged to the floorConstant Speed Brake to slow down Accelerator pegged
9、 to the floorConstant Speed Brake to slow down Accelerator pegged to the floorConstant Speed Brake to slow down Accelerator pegged to the floorVariable Speed Full control of accelerator Brake only if necessaryVariable Speed Full control of accelerator Brake only if necessaryVariable Speed Full contr
10、ol of accelerator Brake only if necessaryHow it WorksHow it WorksHow it Works How it Works How it Works How it Works Control is Key to Energy Savings ACC “learns” how the chiller operates Maps exact surge points Allows operation near surge points Minimizes speed for peak efficiencyComponentsComponen
11、tsEvaporator ShellCondenser ShellElectric MotorGearsImpellerPrerotation VanesConstant SpeedVariable SpeedConstant SpeedVariable SpeedPRV close as load decreasesMotor speed remains constantConstant SpeedVariable SpeedPRV close as load decreasesMotor speed remains constantConstant SpeedVariable SpeedA
12、daptive Capacity Control logicOptimizes compressor efficiencyMotor speed slows downOptimizes PRV positionConsumes less energyPRV close as load decreasesMotor speed remains constantConstant SpeedVariable SpeedAdaptive Capacity Control logicOptimizes compressor efficiencyMotor speed slows downOptimize
13、s PRV positionConsumes less energyPRV close as load decreasesMotor speed remains constantFixed vs Variable SpeedFixed vs Variable Speed YESIV Program ARI Certified Includes VSD losses Includes Filter lossesFixed vs Variable Speed Fixed Speed at ARI conditionsFixed vs Variable Speed Fixed Speed at AR
14、I conditions% Load 100 90 80 70 60 50 40 30 20 10Fixed vs Variable Speed Fixed Speed at ARI conditions% LoadECWT 100 85.0 90 81.0 80 77.0 70 73.0 60 69.0 50 65.0 40 65.0 30 65.0 20 65.0 10 65.0Fixed vs Variable Speed Fixed Speed at ARI conditions% LoadECWTKW/TON 100 85.00.582 90 81.00.532 80 77.00.5
15、00 70 73.00.481 60 69.00.470 50 65.00.463 40 65.00.494 30 65.00.557 20 65.00.700 14 65.01.138Fixed vs Variable Speed Fixed and variable speed at ARI conditionsFixed vs Variable Speed Fixed and variable speed at ARI conditions% Load 100 90 80 70 60 50 40 30 20 10Fixed vs Variable Speed Fixed and vari
16、able speed at ARI conditions% LoadECWT 100 85.0 90 81.0 80 77.0 70 73.0 60 69.0 50 65.0 40 65.0 30 65.0 20 65.0 10 65.0% LoadECWTKW/TON 100 85.00.582 90 81.00.532 80 77.00.500 70 73.00.481 60 69.00.470 50 65.00.463 40 65.00.494 30 65.00.557 20 65.00.700 10 65.01.138Fixed vs Variable Speed Fixed and
17、variable speed at ARI conditionsFixed vs Variable Speed Fixed and variable speed at ARI conditions% LoadECWTKW/TONKW/TON 100 85.00.5820.599 90 81.00.5320.502 80 77.00.5000.441 70 73.00.4810.388 60 69.00.4700.339 50 65.00.4630.293 40 65.00.4940.292 30 65.00.5570.326 20 65.00.7000.373 10 65.01.1380.58
18、4Fixed vs Variable Speed Fixed and variable speed at ARI conditions% LoadECWTKW/TONKW/TON%SAVED 100 85.00.5820.599 -2.92 90 81.00.5320.502 5.64 80 77.00.5000.441 11.80 70 73.00.4810.388 19.33 60 69.00.4700.339 27.87 50 65.00.4630.293 36.72 40 65.00.4940.292 40.89 30 65.00.5570.326 41.47 20 65.00.700
19、0.373 46.71 10 65.01.1380.584 48.680.20.30.40.50.60.70.80.91.01.11.2100%80%60%40%20%LoadkW / tonConstant SpeedVariable Speed Centrifugal Chillers0.20.30.40.50.60.70.80.91.01.11.2100%80%60%40%20%LoadkW / tonConstant SpeedVariable SpeedVariable Speed Centrifugal Chillers0.20.30.40.50.60.70.80.91.01.11
20、.2100%80%60%40%20%LoadkW / tonConstant SpeedVariable SpeedVariable Speed Centrifugal Chillers30% Energy SavingsFixed vs Variable Speed Lower ECWTs means even better performanceFixed vs Variable Speed Lower ECWTs means even better performance 55F is a good low pointFixed vs Variable Speed Lower ECWTs
21、 means even better performance 55F is a good low point York Headquarters Bldg chiller runs on 50F 0.250.300.350.400.450.500.550.600.6585 F80 F75 F70 F65 F60 FEntering Condenser Water TemperaturekW / ton0.250.300.350.400.450.500.550.600.6585 F80 F75 F70 F65 F60 FEntering Condenser Water TemperaturekW
22、 / tonTraditional60% Load100% Load80% LoadYORK (lecwt)60% Load100% Load80% Load0.250.300.350.400.450.500.550.600.6585 F80 F75 F70 F65 F60 FEntering Condenser Water TemperaturekW / tonTraditional60% Load100% Load80% LoadYORK (lecwt)60% Load100% Load80% LoadTraditional60% Load100% Load80% Load0.250.30
23、0.350.400.450.500.550.600.6585 F80 F75 F70 F65 F60 FEntering Condenser Water TemperaturekW / tonYORK w/ Variable Speed100% Load80% Load60% LoadFixed vs Variable Speed Weather data in YESIV is the best way to utilize the actual lower ECWTsFixed vs Variable Speed An additional way to get more energy s
24、avings is with chilled water resetFixed vs Variable Speed An additional way to get more energy savings is with chilled water reset Chiller water reset will help with both low ECWTs or higher tower water conditions Mild outdoor temperatures Lower outdoor humidity levels Less need for dehumidification
25、 Adequate cooling at higher chilled water tempsChilled Water Reset Mild outdoor temperatures Lower outdoor humidity levels Less need for dehumidification Adequate cooling at higher chilled water tempsChilled Water Reset Constant speed 0.5 - 1.5% Variable speed 2.0 - 3.0%Drive Type Savings / Degree I
26、ncreaseEnergy SavingsChilled Water ResetFixed vs Variable Speed 1F chilled water reset per 10% load at ARI conditions and fixed speed% Load ECWT lchwt kw/tr lchwt kw/tr %saved 100 85.0 90 82.5 80 80.0 70 77.5 60 75.0 50 72.5 40 70.0 30 67.5 20 65.0 10 62.5 Fixed vs Variable Speed 1F chilled water re
27、set per 10% load at ARI conditions and fixed speed% Load ECWT lchwt kw/tr lchwt kw/tr %saved 100 85.0 44 0.560 90 82.5 44 0.533 80 80.0 44 0.510 70 77.5 44 0.498 60 75.0 44 0.495 50 72.5 44 0.501 40 70.0 44 0.518 30 67.5 44 0.563 20 65.0 44 0.682 10 62.5 44 1.099Fixed vs Variable Speed 1F chilled wa
28、ter reset per 10% load at ARI conditions and fixed speed% Load ECWT lchwt kw/tr lchwt kw/tr %saved 100 85.0 44 0.560 440.560 90 82.5 44 0.533 45 0.524 80 80.0 44 0.510 46 0.497 70 77.5 44 0.498 47 0.483 60 75.0 44 0.495 48 0.478 50 72.5 44 0.501 49 0.481 40 70.0 44 0.518 50 0.498 30 67.5 44 0.563 51
29、 0.555 20 65.0 44 0.682 52 0.728 10 62.5 44 1.099 53 1.440 Fixed vs Variable Speed 1F chilled water reset per 10% load at ARI conditions and fixed speed% Load ECWT lchwt kw/tr lchwt kw/tr %saved 100 85.0 44 0.560 440.560 0.00 90 82.5 44 0.533 45 0.524 1.69 80 80.0 44 0.510 46 0.497 2.55 70 77.5 44 0
30、.498 47 0.483 3.01 60 75.0 44 0.495 48 0.478 3.43 50 72.5 44 0.501 49 0.481 3.99 40 70.0 44 0.518 50 0.498 3.86 30 67.5 44 0.563 51 0.555 1.42 20 65.0 44 0.682 52 0.728 -6.74 10 62.5 44 1.099 53 1.440 -31.030.30.40.50.60.70.80.91.01.1100%80%60%40%20%LoadkW / tonConstant SpeedConstant Speed Centrifug
31、al Chillers0.30.40.50.60.70.80.91.01.1100%80%60%40%20%LoadkW / tonConstant SpeedConstant w/resetConstant Speed Centrifugal ChillersFixed vs Variable Speed 1F chilled water reset per 10% load at ARI conditions and variable speed% Load ECWT lchwt kw/tr lchwt kw/tr %saved 100 85.0 90 82.5 80 80.0 70 77
32、.5 60 75.0 50 72.5 40 70.0 30 67.5 20 65.0 10 62.5 Fixed vs Variable Speed 1F chilled water reset per 10% load at ARI conditions and variable speed% Load ECWT lchwt kw/tr lchwt kw/tr %saved 100 85.0 44 0.585 90 82.5 44 0.537 80 80.0 44 0.497 70 77.5 44 0.466 60 75.0 44 0.438 50 72.5 44 0.432 40 70.0
33、 44 0.419 30 67.5 44 0.429 20 65.0 44 0.481 10 62.5 44 0.665 Fixed vs Variable Speed 1F chilled water reset per 10% load at ARI conditions and variable speed% Load ECWT lchwt kw/tr lchwt kw/tr %saved 100 85.0 44 0.585 44 0.585 90 82.5 44 0.537 45 0.524 80 80.0 44 0.497 46 0.475 70 77.5 44 0.466 47 0
34、.433 60 75.0 44 0.438 48 0.393 50 72.5 44 0.432 49 0.382 40 70.0 44 0.419 50 0.363 30 67.5 44 0.429 51 0.357 20 65.0 44 0.481 52 0.370 10 62.5 44 0.665 53 0.480Fixed vs Variable Speed 1F chilled water reset per 10% load at ARI conditions and variable speed% Load ECWT lchwt kw/tr lchwt kw/tr %saved 1
35、00 85.0 44 0.585 44 0.585 0.00 90 82.5 44 0.537 45 0.524 2.42 80 80.0 44 0.497 46 0.475 4.43 70 77.5 44 0.466 47 0.433 7.08 60 75.0 44 0.438 48 0.393 10.27 50 72.5 44 0.432 49 0.382 11.57 40 70.0 44 0.419 50 0.363 13.37 30 67.5 44 0.429 51 0.357 16.78 20 65.0 44 0.481 52 0.370 23.08 10 62.5 44 0.665
36、 53 0.480 27.820.30.40.50.60.70.80.91.01.1100%80%60%40%20%LoadkW / tonConstant SpeedConstant Speed Centrifugal Chillers0.30.40.50.60.70.80.91.01.1100%80%60%40%20%LoadkW / tonConstant SpeedConstant w/resetConstant Speed Centrifugal Chillers0.30.40.50.60.70.80.91.01.1100%80%60%40%20%LoadkW / tonConsta
37、nt SpeedConstant w/resetVariable SpeedVariable Speed Centrifugal Chillers0.30.40.50.60.70.80.91.01.1100%80%60%40%20%LoadkW / tonConstant SpeedConstant w/resetVariable SpeedVSD w/ resetVariable Speed Centrifugal ChillersThe New VSD Unit Mounted UL Approved Water Cooled Any Refrigerant Any Compressor
38、York Design Standard Features Circuit breaker UL listed ground fault protection All drive displays on chiller panel Single point wiring No additional floor space requiredElectronic Filter Optional EPRI funded specially designed filter that complies with IEEE 519-1992 Filter is unit mounted in the sa
39、me cabinet as the VSD Still has the UL label Filter parameters displayed on the chiller panelOperating Benefits Slower minimum speed of 30 hz 0.95 or better total power factor at all loads 0.98 or better total power factor with optional filter Takes the place of the starter Reduces inrush to less th
40、an 100% FLA Anti-recycle timer - 0 min Reduced driveline wearPanel Displays Include Volts, amps, hz, kw, kwh Filter total harmonic distortion of voltage Filter total demand distortion of current Unit total power factor Self diagnostic service parametersStandard Safeties Overvoltage protection Underv
41、oltage protection 3 phase sensing motor overcurrent Single phase protection Insensitive to phase rotation Over temperature protectionQuieter OperationSound Generated by refrigerant discharge at high velocitiesSound Generated by refrigerant discharge at high velocitiesSound Slowing compressor reduces
42、 sound Generated by refrigerant discharge at high velocitiesSound Slowing compressor reduces sound Generated by refrigerant discharge at high velocitiesThe Millennium Variable Speed Drive also serves as the starter.Soft Start Never exceed 100% FLA Increase motor life Excellent for limited inrush cap
43、abilities (generator starts)Inrush Current05102040100%200%300%400%500%Motor FLA (%)Time (sec)Inrush Current05102040100%200%300%400%500%Motor FLA (%)Time (sec)Star Delta StarterInrush Current05102040100%200%300%400%500%Motor FLA (%)Time (sec)Star Delta StarterMillennium VSDMinimal VSD Maintenance Cha
44、nge inhibitor Flush heat exchanger Can be performed when cleaning tubesHarmonics What are Harmonics?Harmonics What are Harmonics? Multiples of the base power line frequency: 60hzHarmonics What do they do?Harmonics What do they do? Cause distortion of the voltage and current sine wave6012018024030036
45、060120180240300360Harmonics What do they do? Cause distortion of the voltage and current sine wave Increase the current used by a product Increase the heating of utility wires and transformers Disrupt the operation of other equipmentHarmonics Many utilities are pushing for lower harmonicsHarmonics M
46、any utilities are pushing for lower harmonics The current standard is IEEE 519-1992Harmonics Many utilities are pushing for lower harmonics The current standard is IEEE 519-1992 It developed acceptable levels of voltage and current distortion produced by a productHarmonics Many utilities are pushing
47、 for lower harmonics The current standard is IEEE 519-1992 It developed acceptable levels of voltage and current distortion produced by a product This is a guideline not a required law Harmonics Calculating ComplianceHarmonics Calculating Compliance The new guideline only allows 5% voltage distortio
48、nHarmonics Calculating Compliance The new guideline only allows 5% voltage distortion The new guideline provides a table for transformer size and allowed % current distortionHarmonics Calculating Compliance The new guideline only allows 5% voltage distortion The new guideline provides a table for tr
49、ansformer size and allowed % current distortion Current distortion is calculated as a “Total Demand Distortion” (TDD)Harmonics Calculating Compliance The new guideline only allows 5% voltage distortion The new guideline provides a table for transformer size and allowed % current distortion Current d
50、istortion is calculated as a “Total Demand Distortion” (TDD) This is the highest current demand in a 12 month period ( job FLA)Harmonics Calculating Compliance The new guideline only allows 5% voltage distortion The new guideline provides a table for transformer size and allowed % current distortion
