space vector
33
A l - A h s a C o l l e g e o f T e c h n o l o g y A l - A h s a C o l l e g e o f T e c h n o l o g y A Proposed Switching Strategy A Proposed Switching Strategy for Space Vector Modulated for Space Vector Modulated Current Link Inverters Connected Current Link Inverters Connected to the Public Grid to the Public Grid ن م ح ر ل ها ل ل ما س ن م ح ر ل ها ل ل ما س م ي ح ر ل ا م ي ح ر ل اDr. Eng. El-Sayed S. A. Said Dr. Eng. El-Sayed S. A. Said Al-Ahsa College of Technology Al-Ahsa College of Technology
-
Upload
elsayed-soliman -
Category
Technology
-
view
1.300 -
download
6
description
Space vector modulation el-sayed soliman
Transcript of space vector
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
A Proposed Switching Strategy A Proposed Switching Strategy for Space Vector Modulated for Space Vector Modulated
Current Link Inverters Connected Current Link Inverters Connected to the Public Gridto the Public Grid
الله الله بسم بسمالرحيم الرحيم الرحمن الرحمن
Dr. Eng. El-Sayed S. A. Said Dr. Eng. El-Sayed S. A. Said Al-Ahsa College of TechnologyAl-Ahsa College of Technology
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Paper AspectsPaper Aspects• Pulse Width Modulations PWMsPulse Width Modulations PWMs
• Space Vector PWMSpace Vector PWM
• CSI-SV Switching SequenceCSI-SV Switching Sequence
• Symmetrical Cell Time Switching Symmetrical Cell Time Switching StrategiesStrategies
• Harmonic Analysis and Modulation Index Harmonic Analysis and Modulation Index
• Digital ImplementationDigital Implementation
• Experimental ResultsExperimental Results
• ConclusionsConclusions
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Pulse Width Modulations Pulse Width Modulations PWMsPWMs
•MModulationodulation in in the area of the area of PPower ower
EElectronicslectronics provides a simple and efficient provides a simple and efficient way for obtaining a way for obtaining a controllablecontrollable AC signal AC signal from either variable or constant DC supply.from either variable or constant DC supply.
E
E
carrierpp
referencpp
Modulation Parameters
Modulation index Ma = = TT
C
MAXON
Frequency ratio Mf = F
F
refrence
carreier
= FF
R
C
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Simple PWM Simple PWM GeneratorGenerator
Carrier PWM Pattern
- The Average
+
Reference
Inputs Modulator Output
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Symmetrical PWMSymmetrical PWM
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Simple PWM Simple PWM GeneratorGenerator
Carrier PWM Pattern
- The Average
+
Reference
Inputs Modulator Output
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Voltage Level ControlVoltage Level Control
Ma=0%
Ma=110%
Over modulation
Ma=100%
Ma=10%
Ma=50%
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Fundamental frequency Fundamental frequency controlcontrol
FC = 500 Hz, Fref = 50 Hz
FC = 750 Hz, Fref = 75 Hz
FC = 1000 Hz, Fref = 100 Hz
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Space Vector Current Link Space Vector Current Link PWMPWM
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Space Vector Current Link Space Vector Current Link PWMPWM
Six realizable current vectors
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Realizing the Mathematical Realizing the Mathematical ModelModel
I ref
t1 t2 t0
T Cell dtI ref0
tdtI1
0 1
ttt dtI
21
12
T
ttCell dtI
210
Assuming that is in sector 1 as shown in Fig.1, the durations
,
and
can be obtained from the following current-time integral:
= +
+
On the other hand the duration t0 = [Tcell – (t1 + t2)]
+
,
I ref
I
1 I
2
For high switching frequency can be assumed constant during each cell time.
, are also considered constant during each cell time while I0 =0
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
9090
3030
0
02
0
013 SinCos
SinCosdc ttI
SinCosTI Cellref
=
(3)
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
SV-CSI Switching SV-CSI Switching SequenceSequence
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Symmetrical Cell Time Switching Symmetrical Cell Time Switching StrategiesStrategies
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Symmetrical Cell Time Switching Symmetrical Cell Time Switching StrategiesStrategies
CellFirst
IandIIII 12,021,,
CellSecond
IandIIII 12,021,,
,
CellFirst
tandtttt
222212
,,,
,
021
CellSecond
tandtttt
222212
,,,
,
021
and
and
CellFirst
IandIIII 12001,,,
CellSecond
IandIIII 10,201,
First Switching Sequence
Second Switching Sequence
For the durations
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Symmetrical Cell Time Switching Symmetrical Cell Time Switching StrategiesStrategies
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Switch & Line CurrentsSwitch & Line Currents
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Harmonics AnalysisHarmonics Analysis
II
Sdc
nout
n
ˆ,
N
iijij
dc
n nnnIB
,..2,1)1()()1( coscos
N
iijij
dcn nnnIA
,..2,1)()1()1( sinsin
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Analytical CalculationsAnalytical CalculationsInfluence Switching Influence Switching SequenceSequence
IIIII 12,021 and,,
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Analytical CalculationsAnalytical CalculationsInfluence Switching SequenceInfluence Switching Sequence
IIIII 12001 and,,
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Analytical Calculations Analytical Calculations MMaa=75%=75%
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Analytical Calculations Analytical Calculations MMaa=50%=50%
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Analytical Calculations Analytical Calculations MMaa=20%=20%
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Analytical CalculationsAnalytical Calculations MMaa=(0-115)% Versus the =(0-115)% Versus the FundamentalFundamental
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Experimental ResultsExperimental Results The SAB80C517A microcontroller has been used for the digital realization of the symmetrical cell time PWM_CSI Line Current Waveform Line Current Waveform
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Experimental ResultsExperimental ResultsSpectra of the Line Current Spectra of the Line Current MMaa=113%=113%
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Experimental ResultsExperimental ResultsSpectra of the Line Current Spectra of the Line Current Ma=48%Ma=48%
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Experimental ResultsExperimental ResultsSpectra of the Line Current Spectra of the Line Current MMaa=10%=10%
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Experimental ResultsExperimental ResultsSpectra of the Line Current MSpectra of the Line Current Maa=50%=50%
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Experimental ResultsExperimental Results
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
Al-A
hsa C
olle
ge o
f Tech
nolo
gy
ConclusionsConclusions• In addition to the limited control range, the classical modulated
techniques can not fulfill most of the harmonic and the wave form constraints of many industrial applications. We have replaced these techniques by the symmetrical cell time space vector PWM_CSI techniques. In this work, the space vector PWM_CSI symmetrical cell time technique, have been realized, implemented and experimentally tested. The measured harmonics of the inverter line currents are found to be in satisfactory agreement with the calculated harmonic contents. The wide dynamic range of the modulation index control and the high utilization factor of the DC link have also been verified experimentally
• In this work a Software synchronizer for a line current inverter connected to the mains line voltage is presented. The synchronizer based on a cell time controlled SPLL technique has been implemented using an Intel 80C517A Microcontroller system. The experimental results show some features of the presented system. They are listed below:
• The SPLL capability to synchronize the inverter to the mains even starting from a wrong phase sequence.
• The flexibility of the SPLL, where it can follow the permissible variation of the fundamental of the mains
