Product: Power Factor & Harmonics: StacoSine: Technical

Power Factor & Harmonics: StacoSine: Technical

PF CORRECTION AND HARMONICS

o Introductiono Power Quality In

Generalo Power Factor Correctiono Harmonicso Related Standardso Symptoms and

Equipment Toleranceso Staco Energy Solutionso Monitoring Harmonics

THE IMPACT OF POWER PROBLEMS

o UPS Aloneo UPS & MBPS

2 Piece Shipping Splito Ambidextrous Side Caro Standard Kick Plateso Easy Transport & Installationo Single Hole or NEMA 2 Hole Landingo Standard UVR For Battery Cabinet

Can Be Configured For Shunt Trip

o $120-$180 Billion/yr. = cost of power outages and disturbances in U.S. economy 1

o 8 hrs, 45 minutes/yr. = typical utility grid downtime (99.9% reliability) in U.S.1

o $41,000/hour = cost of downtime, cellular communications 2

o $100,000/minute = lost sales, datacom/networking end user 3 o $8,000 = cost of voltage sag event -- average for all business 5

o $11,000 = cost of momentary outage event -- average for all business 5

o 30% of equipment insurance claims are due to electrical problems 6

o 68% of plant engineers and specifier’s state that “solving P.Q. issues is a very important challenge” 7

1 - EPRI -- Primen Study: The cost of Power Disturbances to Industrial and Digital Economy Companies

2 - 2001 U.S. DOE Distributed Energy Resource Program and Strategic Plan3- Venture Development Corporation Survey

4 - Energy Conservation News5 - 1996 Duke Power Survey6 - Hartford Steam Boiler 7 - EC&M Survey

THE CAUSES OF POWER PROBLEMS




From Outside the Facility: Environmental problems affecting grid

reliability -- e.g., lightning, weather extremes, animal intrusion, resulting in:

Electrical outages, disruptionsVoltage sags and surgesTransients and overvoltagesFrequency or Harmonic problems

Operational Issues, including de-regulation, affecting grid reliability:

Reduction in MaintenanceAging Transmission SystemDemand / Supply (e.g. Calif..)Consolidations / MergersFinancial Concerns

From within the Facility: Aging building infrastructure or

equipment Building not designed for electronic

loads New equipment and processes do

not include mitigation solutions Improper wiring and grounding Outdated electrical system Equipment failures Improper maintenance Overloaded circuits Non-coordinated circuit protection

and/or electrical loads

POWER QUALITY PYRAMID™




Relative CostHigh $/kVA

Low $/kVA The P.Q. Pyramid: Start with Grounding; add

other mitigating products where required

Outages (UPS; ATS; Flywheel; Gen)

Harmonic Distortion (Active/Passive Filters; K-Factor, Phase Shifting)

Voltage Variations (Tap Changer, Sag Correction, Ferro’s, DVR)

TVSS/PFC (AC,DC,Dataline)

Grounding/Bonding (ground rods, fittings, lightning system)

P.Q. SOLUTIONS ARE OFTEN CUSTOM: COST VARY LOCATION AND/OR INDUSTRY




Manufacturing Facility (Medium Sized 480 V, 1000A)(eg. Plastics, Automation, or Higher Tech Assembly)

Capital ($ 000's)

Possible P.Q. SolutionSimple

SolutionMed Complex

SolutionP.Q. Survey = $0 $2 $15Grounding equipment = $0 $1 $5Lightning System = $0 $0 $20Surge Protection (hardwire, datacom) = $0 $5 $20

Surge Strips = $1 $1 $2Voltage Regulation/Sag Correction = $0 $0 $60

UPS (servers, telcom system, other small boxes) =

$4 $8 $12

Harmonics (reactors, capacitors, )= $0 $1 $20Ferroresonant or other power conditioners =

$2 $4 $6

Power Quality Monitor = $0 $1 $10Total $6.8 $21.4 $170.0

Does not include installation or ongoing maintenance

Other potential equipment: PDU, shielded isolation transformers,

parallel gear, generators, ATS

WHAT IS POWER FACTOR?

"Power factor" involves a relationship between two types of power: Working or Real

Power and Reactive Power. oWorking Power, which

performs the actual work of creating heat, light, motion, etc.

oReactive Power, which sustains the electromagnetic field.

WHAT IS POWER FACTOR?oWorking Power

• Normally measured in kilowatts (kW). It does the "work" for the system--providing the motion, heat, or whatever else is required.

oReactive Power• Normally measured in kilovolt-amperes-reactive (kVAR),

doesn't do useful "work." It simply sustains the electromagnetic field.

oWorking Power and Reactive Power together make up Apparent Power. • Apparent Power is normally measured in kilovolt-amperes

(kVA).

WHAT IS POWER FACTOR?

oPower Factor is the ratio of Working Power to Apparent Power, or kW/kVA.

oPower Factor = Working Power / Apparent Power

PF = Cos Θ = kW / kVA

Θ

kW

kVA

APPARENT & DISPLACEMENT PF

oCalculation of displacement power factor:

• PF displacement = WATT/

[WATT2 + VAR2]. • Only the 60 Hz

components are measured.

• For use in power factor correction calculations.

oCalculation of apparent power factor:

• PF apparent = WATT/VA.

• This includes all measured harmonics.

WHAT DOES POWER FACTOR MEASURE?

oPower factor measures how effectively electrical power is being used. • A power factor reading close to 1.0 means that electrical power is

being utilized effectively, while a low power factor indicates poor utilization of electrical power.

oExample:• If you had a paper mill that was operating at 100 kW and the

Apparent Power consumed was 125 kVA, what is the Power Factor?

• This represents a fairly normal Power Factor. PF = 100 kW / 125 kVA

PF = 0.80

IS LOW POWER FACTOR A PROBLEM?oLow power factor means you're not fully utilizing

the electrical power you're paying for.

oIn the earlier example, with a Power Factor of 0.80

or 80%, your paper mill would be utilizing only 80% of the energy supplied by the utility. That means only 80% of the incoming current is being used to produce useful work.

POWER FACTOR BASICS

Utility and Energy Firms Billing Practices

oVaries by company due to type user, contract, mergers, deregulation

oMay include Kva, Kwh, demand, penalty or surcharge

oDiscuss billing components with service provider for better understanding

TYPICAL ENERGY BILLCustomer:Customer: AnyAny Payment To:Payment To: Large Power Co.Large Power Co.Billing Period From:Billing Period From: 9/1/01 12:00:01 AM9/1/01 12:00:01 AM To:To: 9/30/01 12 Midnight 9/30/01 12 Midnight

Demand (Power) Demand (Power) Rate PeriodRate Period Peak atPeak at kVAkVA $/kVA $/kVA ChargeCharge

Off PeakOff Peak 10:35 PM10:35 PM 1,4871,487 3.253.25 $4,832.75$4,832.75On PeakOn Peak 1:05 PM1:05 PM 2,4962,496 16.7516.75 $41,808.00$41,808.00

EnergyEnergy kW hrkW hr $ / kW$ / kW.hrhrOff PeakOff Peak 224,600224,600 0.03690.0369 $8,287.74$8,287.74On PeakOn Peak 458,800458,800 0.0520.052 $23,857.60$23,857.60

Other Charges Other Charges Connection ChargeConnection Charge $500.00$500.00Power Factor Adj.Power Factor Adj. $390.00$390.00State Energy ChargeState Energy Charge 683,400683,400 -0.009-0.009 -$615.06-$615.06Taxes & Special ChargesTaxes & Special Charges $3,178.04$3,178.04

Total DueTotal Due $82,239.07$82,239.07

ENERGY MANAGEMENT

okW Hour (Usage - 1¢ - 15¢/kWH)okW Demand (15 Minute - $5 - $300/kW)oRatio of Usage to DemandokVAR (Power Factor) Penalties

ExamplePower Factor Penalty0.699 or lower Not permitted – 25%0.700 to 0.749 3%0.750 to 0.799 2%0.800 to 0.849 1%0.850 to 1.000 No penalty

WHAT CAN BE DONE?

oThe easiest solution which can improve power factor is to add power factor correction capacitors to your electrical distribution system.

oCapacitors act as reactive current generators. By providing the reactive current, reactive current is no longer drawn from the utility.

oCurrent that is drawn from the voltage source is then only used to do real work (kW) and not to create a magnetic field (kVAR). The source current is then minimized!

WHY CONSIDER PF CORRECTION?

oPF capacitors provide many benefits:1. Reduced electric utility bills (a typical payback period is less than one year)2. Increased system capacity3. Improved voltage regulation4. Reduced heat losses in transformers & cables

oApplications that typically exhibit low Power Factors use motors and include:• air compressors• plastics extruders• machine tools• stamping• and others.

TYPICAL UNCORRECTED POWER FACTOR

By Industry PercentPower Factor

By Operation PercentPower Factor

Auto parts 75-80 Air compressor:Brewery 76-80 External motors 75-80Cement 80-85 Hermetic motors 50-80Chemical 65-75 Metal working:Coal mine 65-80 Arc welding 35-60Clothing 35-60 Arc welding with

standard capacitors

40-60

Electroplating 65-70 Resistance welding 40-60Foundry 75-80 Machining 40-65Forge 70-80 Melting:Hospital 75-80 Arc furnace 75-90Machine manufacturing 60-65 Inductance furnace

60Hz100

Metalworking 65-70 Stamping:Office building 80-90 Standard speed 60-70Oil-field pumping 40-60 High speed 45-60Paint manufacturing 55-65 Spraying 60-65Plastic 75-80 Weaving:Stamping 60-70 Individual drive 60Steelworks 65-80 Multiple drive 70Textile 65-75 Brind 70-75Tool, die, jig 60-65

APPLYING PF CAPACITORS

oSome factors that should be considered when applying PF capacitors:

• Where to apply?• Low voltage or medium voltage?• Fixed vs. Switched?


oWhere to apply?• When applied close to the load (i.e. motor)

transformer and cable losses are reduced.• Lower installation cost when applied in a

central location.• Commonly applied at the utility metering

point.


oLow voltage or medium voltage?• When applied on the 480V side of a substation

transformer and cable losses are reduced.• This may required multiple banks.• When utility feed is medium voltage a single bank at

PCC is often lowest cost.• Must first determine all the reasons for installing PF

capacitors:• Only to reduce utility bill?• Reduce load on cables and transformers?


oFixed vs. Switched?• Fixed banks are simplest and lowest cost but can cause

problems:• Leading PF - some utilities charge• Overvoltage conditions when load drops

• If the plant load is fairly constant a fixed bank may work.• Usually a combination of some amount of fixed capacitance

and switched steps works best.• Also need to consider # of steps.

HARMONIC DISTORTION

oHarmonic problems are becoming more apparent because more equipment that produce harmonics

are being applied to power systems Harmonic

Solutions

SOURCES

General categories of nonlinear loads are:o Power Electronic Equipmento Arcing Deviceso Iron Saturating Deviceso Rotating Machines

SYMPTOMS

oTransformer heatingoMotor and generator heating

and vibrationsoNeutral heatingoNuisance fuse operationso Insulation deteriorationoElectronic control malfunctioningo Inconsistent meter readingsoVoltage regulator misoperations

HARMONICS BASICS

Harmonics and PFCoCapacitors do not create harmonicsoConcern for resonance – currents

amplified, voltage distortion, potential damage to capacitors

oReactors help to “de-tune” to below a certain order, balancing the capacitive requirement

HARMONICS APPLICATION REVIEW

oFacility walk-through – installed equipment, systems and processes

oReview plant electrical documentsoNote plans for new equipment,

expansionoAnalyze 6-12 months of electric billsoReview past electrical system studies,

may require a PQ survey, energy audit

HARMONICS APPLICATION REVIEW

oNote equipment most vulnerable to harmonics

oAny critical loads and process requiring “premium power”, outage concerns?

oReview downtime, scrap, maintenance, equipment replacement costs, loss of production, profits

oIsolated solution, long term PQ strategy

HARMONIC BASICS

Where Harmonics Exist

oWater treatment, glass making, steel processing, packaging, data centers, printing/publishing, paper processing, plastics, chemicals, automotive, to name few

HARMONIC BASICS

Economic Considerations

o Harmonics can create nuisance problems (rebooting a PC, restarting equipment) to serious concerns (product quality issues), through catastrophic events (production halted)…….monies lost

HARMONIC BASICS

oNew and replacement equipment/controls and devices typically are electronic, which may exacerbate a border-line harmonic condition, immediately creating a new set of problems, which ultimately affect business…….monies lost

oPartial “fixes”, lack to review total PQ situation……..monies lost

HARMONIC BASICS

SuggestionsoKeep a record of problems and

associated costsoActions taken to review and “fix”

problem(s), associated costsoPotential need to monitor (collect data)

on facility loads, to help with evaluationoDiscuss problem with a “solutions

driven” equipment manufacturer

HARMONICS & CAPACITORS

oCapacitors not only supply reactive power to the loads in an electrical distribution system they also change the resonance frequency of the system.

oCapacitors are also a “sink” for harmonic currents present in a system.

oWhen the resonance frequency of a system with PF correction capacitors is close to the frequency of a harmonic current generating load parallel resonance can occur.

HARMONIC DISTORTION

480 V

Xs

M

XT

G

HARMONIC DISTORTION

480 V

Xs

M

XT

UPSElectronic Ballast

+ -M

Blocking Filter

G

Welder

HARMONICS 100%, 60 Hz

2%, 780 Hz

20%, 180 Hz

12%, 300 Hz

4%, 420 Hz

2%, 660 Hz

%100...

%1

24

23

22 ×

+++=

I

IIITHDI

HARMONIC DISTORTION STANDARDSHarmonic Voltage Distortion LimitsIEEE Standard 519 – 1992

Maximum Voltage Distortion in % at PCC*

Below 69kV 69-138kV >138kV

Maximum for Individual Harmonic 3.0 1.5 1.0

Total Harmonic Distortion (THD) 5.0 2.5 1.5

* % of Nominal Fundamental Frequency Voltage

HARMONIC DISTORTION STANDARDS

Harmonic Order (Odd Harmonics)

Isc/IL <11 11<h<17 17<h<23 23<h<35 35<h %TDD

Maximum Harmonic Current DistortionIEEE Standard 519 – 1992

In Percent of Fundamental

<20* 4.0 2.0 1.5 0.6 0.3 5.0

20-50 7.0 3.5 2.5 1.0 0.5 8.0

50-100 10.0 4.5 4.0 1.5 0.7 12.0

100-1000 12.0 5.5 5.0 2.0 1.0 15.0

>1000 15.0 7.0 6.0 2.5 1.4 20.0

EXPECTED HARMONICS

H = NP+/-1

i.e. 6 Pulse Drive - 5, 7, 11, 13, 17, 19,…

Source Typical Harmonics*6 Pulse Drive/Rectifier 5, 7, 11, 13, 17, 19…

12 Pulse Drive /Rectifier 11, 13, 23, 25…

18 Pulse Drive 17, 19, 35, 37…

Switch Mode Power Supply 3, 5, 7, 9, 11, 13…

Florescent Lights 3, 5, 7, 9, 11, 13…

Arcing Devices 2, 3, 4, 5, 7...

Transformer 2, 3, 4

* Generally, magnitude decreases as harmonic order increases

VOLTAGE NOTCHING

PARALLEL RESONANCE

PARALLEL RESONANCE

CAP

SCR MVAR

MVAf =

600 kVAR

1500 kVA5.0%

480 V

Xs

200 HPVSD

500 HP

MOTOR HEATING AND VIBRATIONS

60 Hz Rotation

5th Harmonic Rotation

NEUTRAL HEATING

C

B

A

N0A at 60 Hz

10A at 60 Hz

10A at 60 Hz

10A at 60 Hz

30A at 180 Hz

10A at 180 Hz

10A at 180 Hz

10A at 180 Hz

HARMONIC SOLUTIONS

• Clean power drives (18 Pulse)

• Clean MCC’s• Active harmonic filters

• Passive harmonic filters

• Blocking filters (drives)• Blocking filters (3rds)

• Zero-sequence traps

• Delta/Wye transformers • Harmonic cancellation (phase shifting transformers)

• Isolation transformers

• Commutation reactors• 200% neutral conductors

• K-factor rated transformers

EFFECT OF DRIVE LINE REACTORS (IEEE519-1992)

PHASE SHIFTING - 12 PULSE

PHASE SHIFTING - 72 PULSE

230KV

69KV

0° -40° -20° -10° 10° -30° 5° -35° -15° -45° -25°

69KV

-5°

0° 0°

HARMONIC CORRECTION SELECTION FOR DRIVES IN MCC’S

Drive Quantity

5 10 15 2010 Hp

50 Hp

125 Hpand up

Parallel / Passive Filter (10-20% Distortion)

SeriesPassive Filter (8-12% Distortion*)

Active Correction (5-20% Distortion)

18 Pulse Drive (5% Distortion*) 30 Hp

* per Drive

Recommendation based on price and MCC integration

STACOVAR SOLUTIONS

oPower Factor and Harmonic Correction

oLow Voltage Class, 240-600vac

oAutomatically switched and fixed

oVirtually unlimited Kvar

oOptimum standard sizes of switched steps

STACOVAR SOLUTIONS

oSmall “footprint” with maximum KvaroStand-alone, multi-unit, integrated

systemsoModular design for expansion and

upgradeabilityoUL508A, complete assembly

STACOVAR SOLUTIONS

oNEMA 1, 12 and 3R enclosures

oOptional circuit breaker, TVSS, CT

o“Off-the-Shelf and application engineered

oThree phase dry-type capacitors

STACOVAR 100KVAR MODULE WITH CAPACITORS, REACTORS, CONTACTORS, FUSES

STACOVAR ZX AND ZXR APPLICATIONS

oPower systems with frequent load changes, voltage sags and surgesoWelding, flicker problemsoSaw mills, elevators, cranesoRolling mills, arc furnacesoEngine-generators, wind power

STACOVAR “TYPICAL” INTERNAL STRUCTURE ARRANGEMENT

Acrobat Document

STACOVAR “TYPICAL” ENCLOSURE ASSEMBLY

Acrobat Document

STACOVAR “TYPICAL” ENCLOSURE PLAN VIEW

Acrobat Document

• STACO CATALOG NUMBERING SYSTEM

• To assist in the understanding of the Staco catalog numbering system, a brief explanation follows:

• Part Number Example

• P A - 0 0 7 5 – 0 1 A 0 1 B – N 4 8 6 W 1 – C B T

• ___ ______ ____________ __ __

• 1 2 3 4 5 6 7 8 9 10

• 1 PA= StacoVar Automatic Power Factor Correction

• 2 0075= 75kvar

• 3 01A= (1), 25kvar step 01B= (1), 50kvar step

• 4 N= No reactors

• 5 48= 480vac

• 6 6= 60hz

• 7 W1= Wall Mounted NEMA 1

• 8 C= Split Core CT- current transformer (option)

• 9 B= Molded Case Circuit Breaker (option)

• 10 T= TVSS –surge protection (option)

STACOVAR SOLUTIONS

Tuned Harmonic FiltersoApplication designed to trap or reduce problem harmonics

ACtive~trACoActive harmonic filters available early second quarter 2005

“At Load” Fixed CapacitorsoAvailable second quarter 2005

ACTIVE~TRAC ACTIVE HARMONIC FILTER

ACTIVE~TRAC

COST OF HARMONIC CORRECTION

Description Typical $/kVA*K-Factor 20Reactor 3-4

Capacitors (LV) 12Switched Capcitors (LV) 25

Single-Tuned Fixed Filter (LV) 35Single-Tuned Switched Filter (LV) 40-50

Single-Tuned Fixed Filter (MV) 12Single-Tuned Switched Filter (MV) 15

Blocking Filter (3rd's) 100Blocking Filter (Drives) 100Active Harmonic Filter 150

Phase-Shifting Transformers 50Note that prices are generalized for comparison only but not absolute.

Some equipment must be fully rated for loads - others can be partially rated

Capacitors are shown for reference only.

Special Considerations for Generators

NOTCHING AND GENERATORS

Generator Source may result in larger commutation notches and transients

HARMONICS AND GENERATORS

Utility Source2.3% THD

Generator Source 5.7% THD

EXAMPLES OF PQ SITE SURVEYS

Oil Platform - Gulf of Mexico• The “Bad Noise” and the “Evil Noise”

Specialty Steel Tubing – Cleveland, OH• Newly installed PF Correction Capacitors Parallel

Resonant at 11th and 13th Harmonics

• Converted Capacitors to Filters

Nuclear Power Plant - Ohio• High Harmonic Distortion with Inverter

• Single Phase Harmonic Filters

EXAMPLES OF PQ SITE SURVEYS

Steel Mill - Pittsburgh, PA• Harmonic Resonance - Filter Failure

Data Center – Cleveland, OH• Harmonics Causing Nuisance Trips of Peak

Sensing Equipment

Video Reproduction Facility - Michigan• Transformer Overheating• Extremely High Harmonic Currents

CASE STUDY - HOSPITAL PF CORRECTION

Problem: Hospital was Penalized for Power Factor by Utility Company

• $2,300/month Penalty• Consultant Already Specified Required Capacitance• Drive Loads on Air Handling System - Harmonics• Potential for Dangerous Harmonic Resonance• Equipment (New Capacitors, Service Transformers and Other Loads) at

Risk

Solution: Power Study and Implementation

• Re-Designed and Implemented Harmonic Filters with Same Required PF Correction Compensation

• Annual Cost of PF Penalty - $27,600• Cost of Analysis and Harmonic Filters - $45,000 (Installed)• Payback - Less than 2 Years

Avoided Costly and Dangerous Situation for Equipment and Kept Payback Within Hospital Constraints

CASE STUDY - PHASE SHIFTING

Solar Crystal R&DProblem: Harmonics from Multiple 15 kW DC Power Supplies

Harmonic Solution: New Facility Design with Phase Shifting (“Harmonic Cancellation”)

4160V

8x15KWFCE

480V 480V

etc.

12470V

480V480V

EXAMPLE - COMPUTER LOADS

Office Building o Problem: Cubicle Furniture “Smoking” as a Result of

Overheated Neutral (High 3rd Harmonics from Computer Loads)

o Solution: Run Separate Neutrals and Install K-Rated Transformers (“Live with Harmonics”)

CASE STUDY - NOTCHINGAutomotive Assembly• Problem: Large DC drives on Stamping Presses Caused

Voltage Notching on 4 kV Bus - Resulted in Incorrect Welding Timing - Recall on “Bad Welds”

Solution: Reduce or Eliminate Notching with Reactors/Filters or Phase Shifting Transformers

480V480V

12470V

4160V

StampingPresses

Welders

EXAMPLE - PQ SITE SURVEY

AF

National Lab - Linear Accelerator• Problem: Operation of Linear Accelerator Causes

Voltage Flicker and Significant Harmonics

Solution: Measurements and Specifications for Active Harmonic Filter Compensation

2MVA 2MVA 1.5MVA 1.5MVA

13.8KV

480V480V

AF

MONITORING HARMONICS

Snapshot - Continuous Loading

Long Term - Suspected Resonance or Significantly Varying Loads

Conditions

o All normal and contingent circuit configurations

o Each capacitor switching step if applicable

o For all characteristic representations of the speed or percent loading of the harmonic producing source(s)

THANK YOU

Toll Free: 866.261.1191 | [email protected] | www.stacoenergy.com

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