filtros de armonicos

Harmonic Suppressors 1MTE CORPORATION

Harmonic Filters

4 Effects of Harmonics4 IEEE-5194 Solutions


Typical VFD Harmonics

Without using any filtering techniques

1 - 20 HP > 100 %

25 - 40 HP 80 - 100 %

50 - 150 HP 60 - 80 %

200 HP and up 50 - 70 %


Typical VFD Harmonics

Depends on Input Line Impedance

0.50% 1% 1.5% 2% 2.5% 3% 5%5th 0.8 0.6 0.5 0.46 0.42 0.4 0.327th 0.6 0.37 0.3 0.22 0.2 0.16 0.12

11th 0.18 0.12 0.1 0.09 0.08 0.073 0.05813th 0.1 0.075 0.06 0.058 0.05 0.049 0.03917th 0.073 0.052 0.04 0.036 0.032 0.03 0.02219th 0.06 0.042 0.03 0.028 0.025 0.022 0.008

% THD - I 102.5 72.2 59.6 52.3 47.6 44.13 34.96Amps

Increase43% 23% 17% 13% 11% 9% 6%

INPUT IMPEDANCEHarmonic Number


Problems Caused by HarmonicsProblems Caused by Harmonics

l Elevated RMS currentl Circuit Breaker Tripsl Nuisance Fuse Operationl Reduced Equipment Life

Transformers, Conductors, Breakers, Switchesl Equipment Malfunctionsl High Frequency Currentsl Reduces Effective Power Factor


IEEE - 519

ISC/IL < 11 11 h < 17 17 h < 23 23 h < 35 35 h TDD

< 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


IEEE - 519

l PCC = At Point of Metering

l PCC = Point Where Non-LinearLoad Meets Linear Loads


IEEE - 519

l TDD = Magnitude of harmonicdistortion as a percent ofmaximum demand current

l THD = Instantaneous value ofharmonic distortion


Harmonic FilteringTechniques

Low Pass (Broad Band) Series Passive Shunt Passive (Tuned) Series PassiveHarmonic Filter Harmonic Filter Harmonic Filter AC Input Reactor

* Minimizes ALL harmonic frequencies

* High Impedance to tuned frequency

* Low impedance to tuned frequency

* Low cost

* Supplies all harmonic frequencies to load rather

than from AC source

* Popular for 1-phase applications to minimize 3rd

harmonic

* Supplies specific harmonic component to load rather

than from AC source* Improves True power factor

* Does not introduce any system resonance

* Does not introduce any system resonance

* Quite effective for the specific tuned frequency

* Small size

* Does not import harmonics from other

sources

* Does not import harmonics from other

sources

* Only required to carry harmonic current, not full

load current

* Will not import harmonics from other non-linear loads

* Does not require existing power system analysis

* Does not require existing power system analysis

* Improves displacement power factor

* Will not create system resonance



* Improves True power factor* Protects against power

line disturbances

* Improves True power factor* Improves True power factor

* Must handle the rated full load current


* Only filters a single (tuned) harmonic frequency


* Can supply non-linear loads only

* Minimally effective other than tuned harmonic

frequencies

* Can create system resonance

* Can only improve harmonic current distortion

to 30-40% at best* Can supply non-linear

loads only* Can import harmonics

form other non-linear loads* Multiple filters required to

satisfy typical desired harmonic limits

* Slightly reduces displacement power factor

* Harmonic analysis required prior to adding this filter to the power system

DISADVANTAGES

* All harmonic frequencies, by varying amounts

* Specific Tuned Frequency Example: 5th Harmonic,

7th Harmonic, 11th harmonic

ADVANTAGES

INSTALLATION

HARMONIC FREQUENCIES

FILTERED

* All Frequencies Above Resonant Frequency

* Specific Tuned Frequency Example: 3rd Harmonic,

5th Harmonic

TECHNIQUE


Harmonic MitigationAlternatives

5 % Line Reactor 30 - 35 % THID

5% Line Reactor + 3% DC Choke 25 - 30 % THID

5th Tuned Harmonic Trap 20 - 30 % THID

5th + 7th Tuned Harmonic Traps 12 - 20 % THID

12 - Pulse Drive (balanced line currents) 15% THID

18 - Pulse Drive (balanced line currents) < 5 % THID

Broad Band Harmonic Filters 8 - 12 % THID


Shunt Filter (Traps)Disadvantages

l System Resonance

l Import Harmonics

l Overvoltage at light load


Shunt Filter (Traps)Disadvantages

l Multiple Sections Required toMeet IEEE - 519 (5th, 7th, 11th)

l System Analysis Required


Broad Band Harmonic Filter



Non Linear

Load



l Guarantees < 12% THID at Input < 8% Available at Premium

l No System Analysis Requiredl No System Resonancel No Harmonics Importedl Filters All Harmonic Frequencies


Where to Use BroadBand Harmonic Filters

l AC Variable Frequency Drives Variable Torque Applications 6-Diode Input Rectifier Bridge Fan & Pump Applications

l For Non-Linear Loads Only



Harmonic Distortion (%)

5th 7th 11th 13th 17th 19th

70

60

50

40

30

20

10

Harmonic Order

No Filter

With Filter

Actual Application Data - 10HP / 460 V


Linear Load MitigationPCC

THID=3%THID=3%

THID=12%THID=12%

NL L L L

25% 25% 25% 25%


Broad Band HarmonicFilter Performance

VFD Input CurrentWithout Filter VFD Input Current With

Filter (9.1% THID)

Actual Application Data - 10 HP / 460 Volts


Broad Band HarmonicFilter Performance

Actual Application Data: 1000 Hp, 600 V

THVD = 1.6 % THID = 9.8 %


IEEE - 519 Solutions

3% Line Reactor

5% Line Reactor

3% Line + 3% DC Reactors

5% Line + 3% DC Reactors

BBHF (12% Max)

BBHF (8% Max)

5 11 14 15 18 42 63

8 18 23 24 29 67 100

12 27 34 36 43 100 100

15 34 43 45 54 100 100

20 45 57 61 71 100 100

Maximum VFD Load if all VFD's use same Harmonic Mitigation Method

Desired % THID at

PCC (IEEE-519)


Harmonic Filter Costs

SolutionExpected THD - I

Cost of 150HP VFD + Solution

5% Line Reactor 25-35% $15K

5th Harmonic Trap 15-30% $20K-$21K

5th + 7th Traps 10-20% $22K - $24K

12-Pulse Drive * 15% $22K

18 - Pulse Drive * < 5% $23K

Broad Band Filter 8 - 12% $17K - $19K

* Based on balanced line voltages.


MTE Gives You...

MTE guarantees < 12% THID

No adverse system interaction

Best performance to cost ratio

No system analysis required

A global delivery system


Harmonic FiltersEach variable frequency drive (VFD) supplied for fan and pump or other variabletorque loads must be supplied with a harmonic suppressor to reduce the totalharmonic current distortion to 12% or less at the filter input terminals. Thesuppressor operation must be independent of and it must not interact with thepower system or source impedances including power factor correctioncapacitors. The suppressor must not import harmonics from any other sources.The suppressor must not create a system resonance condition. The suppressormust not increase facility electrical system voltage under any loading conditions.The suppressor must improve true power factor to 90% minimum (lagging orleading). Leading power factor is acceptable provided that it does not cause thesystem voltage to be elevated. The watts loss of the suppressor must be nomore than 4% of the load for which it is rated. The harmonic suppressor must beMTE Corporation type DBF Broad Band Harmonic Filter.

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