Date post: | 05-Mar-2016 |
Category: |
Documents |
Upload: | davi-miattello-rf |
View: | 9 times |
Download: | 0 times |
of 71
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.
PUBLIC
PUBLIC - 5058-CO900H
Consideraes sobre Harmnicas
Raymond Schmitz
SP Maio 2015
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 2Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Sistema com inversor
Transformador Inversor Motor
M
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 3Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Transformador Inversor Motor
Corrente harmnicas de rede
M
Sistema com Inversor
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC
Harmnicas -Tpicos
4
Definio.
Efeitos das correntes harmnicas
Medindo as harmnicas (onde ?)
Porque os inversores produzem harmnicas ?
Entendendo a IEEE-519
Variao das harmnicas em funo da carga
Efeito das harmnicas sobre o fator de potncia
Como minimizar as harmnicas
Ferramenta para estimar as harmnicas
Concluso
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.
PUBLIC
PUBLIC - 5058-CO900HCopyright 2005 Rockwell Automation, Inc. All rights reserved. 5
Definio
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 6
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
De maneira facil e didtica podemos dizer que...
A RSS da FFT
deve atender
a THD e a TDD
Recomendado pela IEEE no PCC
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC
O que so Harmnicas ?
7
Harmnicas so correntes parasitarias que vo se somar na correntefundamental.
Harmnicas causam a distoro de uma forma de onda puramente senoidal.
Harmnicas so multiplos inteiros da frequncia fundamental de um sistema.
para um sistema em 50Hz , 5a. 250Hz, 7a. 350 Hz
para um sistema em 60Hz, 5a. 300Hz, 7a. 420 Hz
Total Harmonic Distortion (THD) a maneira de quantificar a distoro total de uma forma de onda.
Todos os retificadores (cargas no lineares) produzem correntes harmnicas querealimentam o sistema de potncia.
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 8Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Quem causa Harmnica ?
Qualquer carga no-linear.
Numa carga no-linear, a corrente no proporcional natenso aplicada.
Carga Linear: Corrente e Tenso
so proporcionais.
VAN
IA
Carga no Linear: Corrente e Tenso
no so proporcionais.
VANIA
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 9Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Exemplos de Cargas lineares
Motores
Resistores de aquecimento
Transformadores ( apos energizao )
Lampadas encandescentes, etc.
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 10Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Exemplos de Cargas no-lineares
Lmpadas Fluorecentes
Fontes Chaveadas
Fornos a Arco
Retificadores, etc.
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 11
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Harmnicas em um Retificador Tpico( 6 Pulsos )
1a., 5a., 7a.
1a. + 5a. (-20%) + 7a. (-13%) + 11a. (9%) + 13a. (7%)
1a. + 5a. (-20%) + 7a. (-13%)
1a. + 5a. (-20%)
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.
PUBLIC
PUBLIC - 5058-CO900HCopyright 2005 Rockwell Automation, Inc. All rights reserved. 12
Efeitos das Correntes Harmnicas
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC
Efeitos das Correntes Harmnicas
13
Correntes harmnicas fluindo em um sistema eltrico iro produzirdistores de tenso em vrios pontos de interligao com outras cargas.
A distoro depende da:
impedncia do sistema ;
amplitude das harmnicas injetadas no sistema ;
relao entre cargas lineares e cargas no-lineares ;
tipo de retificador utilizado (Ex : 6 Pulsos, 12 Pulsos, etc...)
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC
Causa raiz com outros equipamentos
14Copyright 2011 Rockwell Automation, Inc. All rights reserved.
Harmnicas de
Corrente
causam
Distoro de Tenso
HARMONIC SOURCE
PLC
EQUIPMENT
TELEPHONE
EQUIPMENT
DATA
PROCESSING
CENTER
PCC
IH
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC
Efeito das correntes harmnicas
15
Problemas com harmnicas podem incluir :
Sobreaquecimento de componentes (motores, capacitores, transformadores, etc) ;
Aumento da corrente total limitando futuras ampliaes do sistema eltrico
Mau funcionamento de equipamentos ;
Interferncias no sistema telefnico ;
Medies incorretas, mau funcionamento dos rels de proteo de sobrecarga ;
Harmnicas causam correntes adicionais que no produzem trabalho ;
Distoro da tenso de alimentao ;
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.
PUBLIC
PUBLIC - 5058-CO900HCopyright 2005 Rockwell Automation, Inc. All rights reserved. 16
Medindo as Harmnicas (Onde ?)
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 17Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Medindo as Harmnicas
Ponto de acoplamento comum (PCC) Geralmente onde o usurio se conecta com a concessionria
DIAGRAMA UNIFILAR
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.
PUBLIC
PUBLIC - 5058-CO900HCopyright 2005 Rockwell Automation, Inc. All rights reserved. 18
Porque os inversores produzem harmnicas ?
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 19
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Topologia de um inversor de frequncia
Converter
AC to DC
Inverter
DC to AC
DC
Bus
Filter
AC DriveA
C M
oto
r Outp
utA
C L
ine I
nput
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 20
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Retificador de entrada
Cbusbus_cap
V0 := Vstart
D1 D2 D3
D5 D6D4
Lar
Lreactor
Lbr
Lreactor
Lcr
Lreactor
Load
I0 := -(load_cur)
I0 := load_cur
load_cur
Llink
Ldclink
75hp, 480V Converter+
V
+
V
La
LsourceI0 := 0
Lb
I0 := -(load_cur)Lsource
Lc
I0 := load_curLsource
ET1
Va
ET2
Vb
ET3
Vc
VMan2
VMab
FML_INIT2
+
V VMac
+
V
VMan1
Simplorer Student Version at www.ansoft.com
Va
Vb
Vc
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 21
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Inversor sem reator no barramento CC
VMab.V = f ...
La.I = f (t, b...
Cbus.V = f (...
VMac.V = f ...
VMan.V [V]...
50.00m
50.00m
100.00m
100.00m
62.50m
62.50m
75.00m
75.00m
87.50m
87.50m
-800.0 -800.0
800.0
0 0
-666.7 -666.7
-333.3 -333.3
333.3 333.3
666.7
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 22
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Inversor sem reator no barramento CC
VMab.V = f ...
La.I = f (t, b...
Cbus.V = f (...
VMac.V = f ...
VMan.V [V]...
50.00m
50.00m
100.00m
100.00m
62.50m
62.50m
75.00m
75.00m
87.50m
87.50m
-800.0 -800.0
800.0
0 0
-666.7 -666.7
-333.3 -333.3
333.3 333.3
666.7
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 24
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Inversor sem reator no barramento CC
VMab.V = f ...
La.I = f (t, b...
Cbus.V = f (...
VMac.V = f ...
VMan.V [V]...
81.50m
81.50m
93.50m
93.50m
82.50m
82.50m
85.00m
85.00m
87.50m
87.50m
90.00m
90.00m
92.50m
92.50m
-100.0 -100.0
800.0
0 0
200.0 200.0
400.0 400.0
600.0 600.0
Vab Vac
Van
Vbus
Ia
400A/ms
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 25
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Retificador de Entrada
Cbusbus_cap
V0 := Vstart
D1 D2 D3
D5 D6D4
Lar
Lreactor
Lbr
Lreactor
Lcr
Lreactor
Load
I0 := -(load_cur)
I0 := load_cur
load_cur
Llink
Ldclink
75hp, 480V Converter+
V
+
V
La
LsourceI0 := 0
Lb
I0 := -(load_cur)Lsource
Lc
I0 := load_curLsource
ET1
Va
ET2
Vb
ET3
Vc
VMan2
VMab
FML_INIT2
+
V VMac
+
V
VMan1
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 26
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Inversor com reator no barramento CC
VMab.V = f ...
La.I = f (t, b...
Cbus.V = f (...
VMac.V = f ...
VMan.V [V]...
150.0m
150.0m
200.0m
200.0m
162.5m
162.5m
175.0m
175.0m
187.5m
187.5m
-800.0 -800.0
800.0
0 0
-666.7 -666.7
-333.3 -333.3
333.3 333.3
666.7
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 27
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Inversor com reator no barramento CC
VMab.V = f ...
La.I = f (t, b...
Cbus.V = f (...
VMac.V = f ...
VMan.V [V]...
181.5m
181.5m
193.5m
193.5m
182.5m
182.5m
185.0m
185.0m
187.5m
187.5m
190.0m
190.0m
192.5m
192.5m
-100.0 -100.0
800.0
0 0
200.0 200.0
400.0 400.0
600.0 600.0
Vab Vac
Van
Vbus
Ia
80A/ms
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 28Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Importante
Harmnicas de corrente
criam
Distoro de tenso
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.
PUBLIC
PUBLIC - 5058-CO900HCopyright 2005 Rockwell Automation, Inc. All rights reserved. 29
Entendendo a IEEE-519
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 31
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
O que devemos fazer com as harmnicas?
No nem econmico nem desejvel eliminar todas as harmnicas.
Guias prticos e anlises so utilizados e/ou necessrios para determinar se ocorrero problemas criados pela introduo de
harmnicas em um sistema.
Normas e Recomendaes :
IEEE-519 (nos EUA e Amrica do Sul)
IEC-555 (Europa e algumas reas na Amrica do Sul)
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 32Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Quais so os limites da IEEE 519-1992 ?
Application Maximum THD (%)
Special Applications - hospitals and airports 3.0%
General System 5.0%
Dedicated System - exclusively converter load 10.0%
Harmonic Voltage LimitsLow-Voltage Systems
Table 10.2
Table 10.3
Current distortion Limits for General Distribution Systems (120V through 69,000V)
Isc/Iload
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 33
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
O objetivo da IEEE 519(Primeiro Mandamento)
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 34
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Quem seu vizinho ?
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 35
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Quem seu vizinho ?
transformertransformer
PCC1
2500kVA
5.75%Z
480Vsec
utility
2500kVA
5.75%Z
480Vsec
utility
Other
Customer
Customer
A
Other
Customer
Customer
B
Other
Customer
Customer
C
Iharm A
Iharm B
Iharm C
Ifund A
Ifund B
Ifund C
Iharm
Ifund
I(TDD) is measured at each metering point
Goal is to
keep the V(THD) at
PCC1
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 37Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Olhando internamente o cliente A
Atende a IEEE-519 no PCC1
PCC1
Isc/Iload = 53.3V(THD) = 2.0%I(TDD) = 11.5%
113Arms
981Arms
V(THD)
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 38
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Atender a IEEE-519 no Inversor ???
bom lembrar que a IEEE 519 uma recomendaopara sistemas de distribuioe nopara equipamentos
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.
PUBLIC
PUBLIC - 5058-CO900HCopyright 2005 Rockwell Automation, Inc. All rights reserved. 39
Variao das Harmnicas em funo da carga
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 40
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Efeito da corrente motor sobre I(THD) ?
I(THD) aumenta a medida que a carga diminue ;I(fund) diminue a medida que a carga diminue ;I(harm) diminue a medida que a carga diminue.
NOTA :I(THD) = Iharm / Ifund
6-Pulse Buffered Drive Currents
0
10
20
30
40
50
60
70
80
90
100
0 20 40 60 80 100% Load
% o
f Full
Load F
und. C
urr
ent
Iharm
Ifund
I(THD)
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.
PUBLIC
PUBLIC - 5058-CO900HCopyright 2005 Rockwell Automation, Inc. All rights reserved. 41
Efeito das Harmnicas no fator de potncia
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 42
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
P.F. Total = Fator de Deslocamento (Displacement P.F.) xFator de Distoro (Distortion P.F.)
As concessionrias medem o Fator de Potncia Total.
A maioria dos fabricantes de inversores falam somente dofator de deslocamento (Displacement Power Factor).
E o Fator de Distoro, e o Fator de Deslocamento, so importantes ?
Fator de Potncia
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 43
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Distortion Power Factor o no alinhamento da Tenso e Corrente devido a distoro das formas de Onda.
Displacement Power Factor Defasagem entre Tenso e Corrente na passagem por zero.
Ambos so importantes e igualmente afetam
o fator de potncia total !
2
1
1
1
THDI
IDF
rms
1cosIDF
O que so Fatores de Distoro e Deslocamento
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.
PUBLIC
PUBLIC - 5058-CO900HCopyright 2005 Rockwell Automation, Inc. All rights reserved. 44
Como minimizar as harmnicas
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 45
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Relao entre Nmero de Pulsos dos
Retificadores e as Harmnicas
As Harmnicas caractersticas (h) em relao ao nmero de pulsos (n) de um retificador dado por :
h= k n 1
k = mltiplo do nmero de pulsos
Ex : 6 pulsos injeta 61= 5a. e 7a., 121 = 11a. e 13a.
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 46
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
A amplitude (A) de uma dada harmnica relacionada com o nmero de pulsos por :
A = 1/h
quanto maior a ordem da harmnica, menor ser sua
amplitude.
Ex : 5a. harmnica 1/5 = 20%, 7a. harmnica 1/7 = 13%.
Relao entre Nmero de Pulsos dos Retificadores e as Harmnicas
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 47
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Retificador de 6 pulsos5a e 7a Harmnicas
Retificador
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 48
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Atravs de um transformador alimentador com multiplos secundrios.
O deslocamento de fase dos secundrios obtido por :
para um retificador de 12 pulsos, o deslocamento de fase deve ser 60/2=30 (Ex : enrolamentos em
no secundrio e Y no tercirio).
para um retificador de 18 pulsos, o deslocamento de fase entre enrolamentos do secundrio sero de
20, 0 e -20 (Ex : configurao dos enrolamentos em delta ou estrela).
windingsondaryofnumbershiftphase
_sec__
60_
Como atingir um maior nmero de pulsos ?
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 49
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Retificador de 12 pulsos11a e 13a Harmnicas
Rectificador de
12 Pulsos
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 50
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Retificador de 18 pulsos17a e 19a Harmnicas
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 51
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Retificador AFE (Active Front End)A
C L
ine I
nput
Converter
AC to DC
Inverter
DC to AC
DC
Bus
Filter
Regenerative AC Drive
AC
Moto
r Outp
ut
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 52
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
THD tpico em funo do retificador
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 53Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Tcnicas de Reduo de Harmnicas
Reator no Barramento CC do inversor (PowerFlex) ;
Reator de Entrada ;
Utilizao de Filtros Ativos ou Passivos de Harmnicas ;
Utilizar inversores com entrada ativa (Entrada AFE/PWM) ;
Aumentar o nmero de pulsos do retificador. Ex : 12 ou 18 pulsos ;
No caso de ter um nmero par de inversores de mesma potncia e commesmo perfil de carga adotar um arranjo pseudo 12 pulsos colocandometade da carga num secundario em estrela e outra metade num
secundario em triangulo ;
Aumentar as cargas lineares em relao s no-lineares, etc.
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 54
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Reator no barramento CC e/ou Reator de entrada
Cbusbus_cap
V0 := Vstart
D1 D2 D3
D5 D6D4
Lar
Lreactor
Lbr
Lreactor
Lcr
Lreactor
Load
I0 := -(load_cur)
I0 := load_cur
load_cur
Llink
Ldclink
75hp, 480V Converter+
V
+
V
La
LsourceI0 := 0
Lb
I0 := -(load_cur)Lsource
Lc
I0 := load_curLsource
ET1
Va
ET2
Vb
ET3
Vc
VMan2
VMab
FML_INIT2
+
V VMac
+
V
VMan1
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 55Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Filtros Passivos
M
hp
Motor
Load
Transformer
xfmr
% Z
Passive Filter
Drive
DC
AC
AC
DC
DC Link
Choke
Ia = f( S,...
-25.00m
-25.00m
24.90m
24.90m
0
0
-20.00m
-20.00m
-10.00m
-10.00m
10.00m
10.00m
20.00m
20.00m
-150.0 -150.0
150.0
0 0
-100.0 -100.0
-50.0 -50.0
50.0 50.0
100.0 100.0
I(THD) de 4 at 7%
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 56Copyright 2005 Rockwell Automation, Inc. All rights reserved.
M
Drive
hp
Motor
Load
Transformer
DC
AC
DC Link
Chokexfmr
% Z
Active Filter
AC
DC
AC
DC
Ifund Ifund + Iharm
Iharm
Ia = f( S,...
-25.00m
-25.00m
24.90m
24.90m
0
0
-20.00m
-20.00m
-10.00m
-10.00m
10.00m
10.00m
20.00m
20.00m
-150.0 -150.0
150.0
0 0
-100.0 -100.0
-50.0 -50.0
50.0 50.0
100.0 100.0
Filtros Ativos
I(THD) tpico de 3 6%
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 57
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Estrela-Tringulo (pseudo 12-Pulsos)
Soluo para dois inversores.
Proporciona uma boa diminuiodo contedo harmnico.
I(THD) de 30% para 15%.
Drive
DC
AC
DC Link
Choke
AC
DCM
Drive
DC
AC
DC Link
Choke
AC
DCM
Transformer
xfmr
% Z
orreactor
Carga : 50% em cada trafo.
(A corrente mostrada ao lado foi medida
com 100% de carga aplicada no
inversor superior e 25% de carga
aplicada no inversor inferior)
La1.I = f...
150.0m
150.0m
200.0m
200.0m
162.5m
162.5m
175.0m
175.0m
187.5m
187.5m
-1000.0 -1000.0
1000.0
0 0
-500.0 -500.0
500.0 500.0
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 58Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Custos das tcnicas de reduo de harmnicas
0 50 100 150 200 250 300
Basic Drive without dc link choke
Addition of dc link choke
Addition of 3% line reactor
Addition of passive filter
12 pulse auto transformer
18 pulse auto transformer
Active filter
Synchronous converter
Relative Installed Cost, %
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 59
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Custos das tcnicas de reduo de harmnicas
$0
$10,000
$20,000
$30,000
$40,000
$50,000
$60,000
$70,000
$80,000
$90,000
10
HP
25
HP
50
HP
75
HP
10
0 H
P
15
0 H
P
20
0 H
P
25
0 H
P
30
0 H
P
40
0 H
P
50
0 H
P
80
0 H
P
Active Filter
Passive Filter
18-Pulse
Active Front-End
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 60
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Custos das tcnicas de reduo de harmnicas -
2010
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 61Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Aumentando as Cargas Lineares
Iharm, A 20 20 20 20
Ifund, A 10 20 100 1000
Itotal, A 22.4 28.3 102.0 1000.2
I(THD) 200% 100% 20% 2%
Lembre-se : I(THD) = Iharm/Ifund
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 62
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Exemplo IEEE-519
Recomendao : 5% de distoro harmnica de tenso.
Transformador de 250KVA c/ 6% de impedncia alimentando um inversor de 150HP.
Inversor sem reator no barramento CC : 6,55 % de distoro harmnica (Acima do recomendado pela IEEE).
Inversor com Reator no Barramento CC : 4,87% de distoro harmnica (Abaixo do recomendado pela IEEE).
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 63Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Tendncias do mercado
12/18 Pulsos - muito bem aceitas no mercado
Geralmente pr-especificados ;
Tecnologia madura e simples ;
Soluo mais barata acima de 150/ 200HP.
Filtros passivos
Soluo competitiva para Inversores
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.
PUBLIC
PUBLIC - 5058-CO900HCopyright 2005 Rockwell Automation, Inc. All rights reserved. 64
Ferramentas para avaliar sua THD
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 65
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Identificar o PCC e aplicar a tcnica mais apropriada (barata) ;
Adicionar reatores AC (ou reator CC se possvel) para inversores comretificadores de 6 pulsos ;
Considerar o uso de filtros ativos para sistemas com mltiplosinversores ;
No caso de existir um nmero par de inversores de mesma potncia ecom mesmo perfil de carga, adotar um arranjo pseudo 12 pulsoscolocando metade da carga no secundrio em estrela e a outrametade no secundrio em tringulo ;
Tentar separar os sistemas de alimentao para as cargas lineares eno-lineares e ter assim limites de THD de tenso diferentes (5% e10%).
Como atender a IEEE519
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 67Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 68Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 69Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 70Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 71Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 72Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 73Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.PUBLIC 74
Copyright 2005 Rockwell Automation, Inc. All rights reserved.
Internet
Internet :
http://www.ab.com : Drives, Get Support, Softwares (Harmonic Calculator, Energy Comparison, etc...), na mesma pgina tem tambem : Informaes Tcnicas
(Technical Inf), Artigos Tcnicos (Technical Articles), etc...
http://www.rockwellautomation.com
http://www.rockwellautomation.com.br
Copyright 2015 Rockwell Automation, Inc. All Rights Reserved.
PUBLIC
PUBLIC - 5058-CO900HCopyright 2005 Rockwell Automation, Inc. All rights reserved. 75
Seguindo estas recomendaes, voc deveratingir um THD aceitvel para sua operao !
Muito obrigado!