Upload
others
View
2
Download
0
Embed Size (px)
Citation preview
Prof. Byoung-Kuk Lee, Ph.D. Energy Mechatronics Lab. School of Information and Communication Eng. Sungkyunkwan University Tel: +82-31-299-4581 Fax: +82-31-299-4612 http://seml.skku.ac.kr EML: [email protected]
-단상 풀브리지 인버터 (II)-
전력전자공학
2 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Topology & Switching Pattern
4 switches with FWD
2 poles
180 degree phase shift between
“a” & “b” pole
Switching pair : Q1,Q2 and Q3,Q4
Interlock or Deadtime
Switching frequency (fsw) = Output
frequency (fo)
부하 io
vo
+_
Q1
Q4
D1
D4
Q3
Q2
D3
D2
+_V
DC
2
O
VDC
2
iDC
+_
va
vb
a 폴 b 폴
t
Q1, Q2 ON OFF ON0
tOFF ON OFF
0
Q3, Q4
1ph Full-Bridge Inverter
전력전자공학
3 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Mode Analysis (I)
• Q1, Q2 – On period
• Inductor (Load) : Back EMF
• Source : Inductor (Load) / Load : DC Link capacitors
• Current flow with D1, D2 (D1, D2 Conduction period)
• Regenerating mode
io
vo-+
Q1
D1
Q2D2
+ Vdc
-
B
t
t
t
t
io
t1
vao
Q1 ON0.5VDC
- 0.5VDC
0.5VDC
- 0.5VDC
VDC
- VDC
Q4 ON
Q1 ON
Q2 ON
Q3 ON
Q2 ON
Q1, Q2
ON
Q3, Q4
ON
Q1, Q2
ON
t2 t3
t4
(= T/2)
( = T )
VDCT
4L
D1, D2
도통Q1, Q2
도통D3, D4
도통Q3, Q4
도통
Reg
en
era
ting
Po
werin
g
0
0
0
A C D
vbo
0
vo
vao-vbo
1ph Full-Bridge Inverter
전력전자공학
4 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Mode Analysis (II)
B
t
t
t
t
io
t1
vao
Q1 ON0.5VDC
- 0.5VDC
0.5VDC
- 0.5VDC
VDC
- VDC
Q4 ON
Q1 ON
Q2 ON
Q3 ON
Q2 ON
Q1, Q2
ON
Q3, Q4
ON
Q1, Q2
ON
t2 t3
t4
(= T/2)
( = T )
VDCT
4L
D1, D2
도통Q1, Q2
도통D3, D4
도통Q3, Q4
도통
Reg
en
era
ting
Po
werin
g
0
0
0
A C D
vbo
0
vo
vao-vbo
• Q1, Q2 – On period
• io : Linear increase
• Source : DC Link capacitors / Load : Inductor (Load)
• Current flow with Q1, Q2
• Powering mode
+ Vdc
-
io
vo-+
Q1
D1
Q2
D2
1ph Full-Bridge Inverter
전력전자공학
5 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Mode Analysis (III)
B
t
t
t
t
io
t1
vao
Q1 ON0.5VDC
- 0.5VDC
0.5VDC
- 0.5VDC
VDC
- VDC
Q4 ON
Q1 ON
Q2 ON
Q3 ON
Q2 ON
Q1, Q2
ON
Q3, Q4
ON
Q1, Q2
ON
t2 t3
t4
(= T/2)
( = T )
VDCT
4L
D1, D2
도통Q1, Q2
도통D3, D4
도통Q3, Q4
도통
Reg
en
era
ting
Po
werin
g
0
0
0
A C D
vbo
0
vo
vao-vbo
• Q3, Q4 – On period for -VDC
• Inductor (Load) : Back EMF
• Source : Inductor (Load) / Load : DC Link capacitors
• Current flow with D3, D4 (D3, D4 Conduction period)
• Regenerating mode
+ Vdc
-
io
vo +-Q4
D4
Q3
D3
1ph Full-Bridge Inverter
전력전자공학
6 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Mode Analysis (IV)
B
t
t
t
t
io
t1
vao
Q1 ON0.5VDC
- 0.5VDC
0.5VDC
- 0.5VDC
VDC
- VDC
Q4 ON
Q1 ON
Q2 ON
Q3 ON
Q2 ON
Q1, Q2
ON
Q3, Q4
ON
Q1, Q2
ON
t2 t3
t4
(= T/2)
( = T )
VDCT
4L
D1, D2
도통Q1, Q2
도통D3, D4
도통Q3, Q4
도통
Reg
en
era
ting
Po
werin
g
0
0
0
A C D
vbo
0
vo
vao-vbo
• Q3, Q4 – On period
• io : Linear decrease
• Source : DC Link capacitors / Load : Inductor (Load)
• Current flow with Q3, Q4
• Powering mode
+ Vdc
-
io
vo +-Q4
D4
Q3
D3
1ph Full-Bridge Inverter
전력전자공학
7 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Analysis (I)
출력전압 vO
• Odd function & Quarter wave symmetry
2
d0
sin
,
8V sin
2
o n
odd
n
v b n t
Quarter wave symmetry
b n t d t
2
0
4 1( cos ) |
4 1sin
n d
o d
odd
b V n tn
v V n tn
2 1sino d
odd
cf Single phasehalf bridgeinverter
v V n tn
Harmonics spectrum
0
0.8
0.6
0.4
0.2
1
1 3 5 7 9 11 13
n
% V n
^
1
3
1
1
7
1
5
Odd harmonics
t
VDC
- VDC
Q1, Q2
ON
Q3, Q4
ON
Q1, Q2
ON0
vo
Fundamental
1ph Full-Bridge Inverter
전력전자공학
8 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Analysis (II)
기본 파 성분의 실효 값 V1,rms
인버터 이득 Gv
인버터 용량 SI
12 2 8V
d
VG
V
2 2
, 1,
1,
2 22 2( )
2 2
0.48 (48%)
o rms rms
rms
o o
o
V VTHD
V
V V
V
1,
1 4
2rms dV V
출력전압 THD
구형파 제어
제어회로 간단, 최대 출력전압 (Vd)
기본파 크기 제어 안됨
하프브리지와 비교하여 파형개선 없음
1 1 1
2 2I o d oS V I V I
1ph Full-Bridge Inverter
전력전자공학
9 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (I)
Schematic
전력전자공학
10 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (II)
Waveform – Gate Signal, Phase Voltage
전력전자공학
11 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (III)
Waveform – Output Current
전력전자공학
12 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (Ⅳ)
Waveform – Output Voltage Harmonic
전력전자공학
13 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Topology & Switching Pattern
• 4 switches with FWD
• 2 poles
• “β” degree phase shift between “a” & “b” pole
• β : Control parameter of fundamental amplitude
• Switching overlap : Q1/Q2 Q1/Q3 Q3/Q4 Q4/Q2
• Switching overlap period (α) : Output voltage = 0
• Use at single phase inverter only
부하 io
vo
+_
Q1
Q4
D1
D4
Q3
Q2
D3
D2
+_V
DC
2
O
VDC
2
iDC
+_
va
vb
a 폴 b 폴
Q1
0
t
1
0 t
1
Q4
0
t
1
0 t
1
Q2
Q3
1ph Full-Bridge Inverter
전력전자공학
14 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Mode Analysis (I)
구간 A,B,D,E 는 구형파 모드해석과 동일 t
t
t
t
io
vo
t1
vao
vbo
Q1 ON0.5VDC
- 0.5VDC
0.5VDC
- 0.5VDC
VDC
- VDC
Q4 ON
Q1 ON
Q2 ON
Q3 ON
Q2 ON
Q1, Q2
ON
Q3, Q4
ON
Q1, Q2
ON
t2 t3
t4 (= T)
D1
D2
Q1
Q2
D3
D4
Q3
Q4
D1
Q3
Q4
D2
t5
t6
Regen
eratin
g
Freew
heelin
g
Pow
erin
g
0
0
0
0
A B C D E F
• α ,β = π/2
• Q1, Q3 – On period (Overlap)
• Inductor (Load) : Back EMF
• Current flow with Q1, D3
• Freewheeling mode
+ Vdc
-
io
vo +-
Q1
D4
Q3 D3
1ph Full-Bridge Inverter
전력전자공학
15 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Mode Analysis (II)
t
t
t
t
io
vo
t1
vao
vbo
Q1 ON0.5VDC
- 0.5VDC
0.5VDC
- 0.5VDC
VDC
- VDC
Q4 ON
Q1 ON
Q2 ON
Q3 ON
Q2 ON
Q1, Q2
ON
Q3, Q4
ON
Q1, Q2
ON
t2 t3
t4 (= T)
D1
D2
Q1
Q2
D3
D4
Q3
Q4
D1
Q3
Q4
D2
t5
t6
Regen
eratin
g
Freew
heelin
g
Pow
erin
g
0
0
0
0
A B C D E F
• α ,β = π/2
• Q2, Q4 – On period (Overlap)
• Inductor (Load) : Back EMF
• Current flow with Q4, D2
• Freewheeling mode
+ Vdc
-
io
vo-+
Q4 Q2 D2
1ph Full-Bridge Inverter
전력전자공학
16 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Analysis (I)
출력전압 vO
실효값
1,3,5
1,3,5
2 sin( ) sin( )
4 sin( / 2)cos[ ( )]
o a b
DC
n
DC
n
v v v
V n t n t n
n
V nn t
n
1
41sin
22
DCVV
(기본파)
(출력전압) 2
0
2( )
2o DC DCV V d t V
VDC
2
VDC
2_
vo
S1
S3
va
vb
0
t
1
0 t
1
0 t
0
t
0
t
VDC
- VDC
VDC
2
VDC
2_
기본파
1ph Full-Bridge Inverter
전력전자공학
17 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Analysis (II)
n차 고조파 및 출력전압 THD
준구형 파 제어
• 기본파의 크기 – 제어가능
• 기본파의 주파수 – 제어가능
• 고조파 성분 – 제어불가능
2 2
1
2
1
18sin ( / 2)
o
v
V VTHD
V
1% sin ( , )
2n
nV n
n
단 홀수
4 DCV
로정규화
실용적 α의 범위
0~90degree
00
0.2
0.4
0.6
0.8
1
0
0.2
0.4
0.6
0.8
1
60
180
120
THDv
THDv
060
120
180
[ degree ]
%Vn^
n=3
n=5n=7
( )n=1
[ degree ]
1ph Full-Bridge Inverter
전력전자공학
18 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (I)
Schematic
전력전자공학
19 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (II)
Waveform – Gate signal
전력전자공학
20 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (III)
Waveform – Phase Voltage, Output Voltage, Output Current
전력전자공학
21 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (Ⅳ)
Waveform – Output Voltage Harmonic
전력전자공학
22 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Switching Pattern (I)
기본파
t
0
1
2
3
2
4
1
0.5
-1
0
- 0.5
t
vc
vr
ma
1
2_
VDC
VDC
1
2
vo
ma
= 0.8 mf = 9
am
기준파의진폭
반송파의진폭
cf
fm
f 반송파의주파수
기준파의주파수
진폭변조지수(amplitude modulation index) : ma
주파수변조지수(frequency modulation index) : mf
Switching Logic Signal
Q1-Q2 Q3-Q4 vo
vr > vc ON OFF Vd
vr < vc OFF ON -Vd
1ph Full-Bridge Inverter
전력전자공학
23 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Switching Pattern (II)
기본파
t
0
1 2
3
2
4
1
0.5
-1
0
- 0.5
t
vc vr
ma
12
_VDC
VDC12
vo
ma = 0.8 mf = 9sinam t
• 인버터 스위칭 주파수 fsw
• 반송파 주파수 fc
• 인버터 출력 주파수 fo
• 기준파 주파수 fr
• 바이폴라 PWM에서는 mf 가 odd여야 symmetry (even harmonic 상쇄)
• 일반적으로 mf > 21
fo=60Hz일 경우, fsw=1.26kHz
fsw = fc
fo = fr
1ph Full-Bridge Inverter
전력전자공학
24 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Analysis
Harmonic Spectrum
• fsw를 높이면 Low order harmonics 제거 가능
• mf 의 정수배의 고조파 군이 나타남
• mf = 21, Lowest order harmonic은 21th
(78.5%)
0.5
10
ma
( , mf = 15 )
2 3 40
1
4
%V1^
3.24
파
, sin (@ 21)o fundamental a d fv m V t m 크기 주파수
1 mf 2mf
h
출력전압 - 기본파
• 기본파 출력전압은 ma에 비례
• ma=1 일 때, 기본파 출력전압은 최대(Vd)가 됨
1ph Full-Bridge Inverter
전력전자공학
25 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (I)
Schematic
전력전자공학
26 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (II)
Waveform – Gate Signal
전력전자공학
27 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (III)
Waveform – Phase Voltage, Output Voltage, Output Current
전력전자공학
28 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (Ⅳ)
Waveform – Output Voltage Harmonic
전력전자공학
29 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (V)
Waveform – Output Voltage, Output Current
전력전자공학
30 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (VI)
Waveform – Output Voltage Harmonic
전력전자공학
31 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (VII)
Waveform – Output Voltage, Output Current
전력전자공학
32 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (VIII)
Waveform – Output Voltage Harmonic
전력전자공학
33 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Switching Pattern (I)
Pole voltage
Output voltage
반대극성에서 만 출력발생 (Vo=Vab=Vao-Vbo)
기본파
0
1
4
t
1
2_
VDC
VDC
1
2
t
1
0.5
-1
0
- 0.5
vc
vra
ma
ma
= 0.8 mf = 8
t
vrb
va
vb
0
1
2_
VDC
VDC
1
2
2
vo
t
VDC
- VDC
1
2
3
3
2
1
4
1
2
3
32
VDC
a 폴iDC
+_
O
VDC
2
부하 io
+_
vo
+_
S4
= S1
VDC
2
S1
S2
= S3
S3
va
vb
b 폴
Switching Logic Signal
Pole “a” Pole “b” vo Q1 Q4 Q2 Q3
vra > vc ON OFF Va=Vdc/2
vra < vc OFF ON Va= -Vdc/2
vrb > vc OFF ON Vb=Vdc/2
vrb < vc ON OFF Vb= -Vdc/2
1ph Full-Bridge Inverter
전력전자공학
34 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Switching Pattern (II)
• 진폭변조지수(amplitude modulation index) : ma
• 주파수변조지수(frequency modulation index) : mf
• Reference waveform
• 유니폴라 PWM에서는 mf가 even이어야 symmetry (odd harmonic 상쇄)
• 일반적으로 mf > 22 (fo=60Hz일 경우, fsw=1.32kHz)
• Effective switching double compare to bipolar PWM
sin
sin
ra a DC
rb a DC
v m V t
v m V t
크기 주파수
am
기준파의진폭
반송파의진폭
cf
fm
f 반송파의주파수
기준파의주파수
기본파
0
1
4
t
1
2_
VDC
VDC
1
2
t
1
0.5
-1
0
- 0.5
vc
vra
ma
ma
= 0.8 mf = 8
t
vrb
va
vb
0
1
2_
VDC
VDC
1
2
2
vo
t
VDC
- VDC
1
2
3
3
2
1
4
1
2
3
32
1ph Full-Bridge Inverter
전력전자공학
35 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Analysis
Harmonic Spectrum
• fsw를 높이면 Low order harmonics 제거 가능
• mf 의 2배수의 고조파 군이 나타남
• mf = 22 이라면, Lowest order harmonic은 44th
PWM 제어 특성
• 기본파의 크기 – 제어가능
• 기본파의 주파수 – 제어가능
• 고조파 성분 – 억제가능
1 2mf 4mf
h
1ph Full-Bridge Inverter
전력전자공학
36 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (I)
Schematic
전력전자공학
37 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (II)
Waveform – PWM Signal
전력전자공학
38 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Waveform – Phase Voltage
Simulation (III)
전력전자공학
39 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (IV)
Waveform – Output Voltage Harmonic
전력전자공학
40 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Simulation (V)
Waveform – Output Current
전력전자공학
41 / 41
Sungkyunkwan Univ., Energy Mechatronics Lab.
Waveform – Output Voltage Harmonic
Simulation (VI)