Download University of Bahrain College of Engineering Department of

AN INTERCONNECTION OF A
PHOTOVOLTAIC GENERATOR (PVG)
With THE POWER UTILITES GRID:
Study Cases
Dr. Maamar Taleb
Electrical and Electronics Engineering Department
University of Bahrain
Energy Economy & Energy Management Forum (EEEMF2015)
for MENA & Fourth Renewable Energy National Dialogue Amman – Jordan
May 18-20, 2015
Agenda
•
•
•
•
•
•
•
•
Motivation and Rationale
Conventional Way of Interconnection
Proposed Idea of Interconnection
PV Panels Characteristics
Control Strategy
Experimental Setup
Performance
Conclusions
MOTIVATION AND RATIONALE
Global Primary Energy Demand
X
3
Primary energy supply (Mtoe)
4000
3500
X
3
3000
2500
2005
2050
X
6
2000
1500
1000
500
0
Coal
Oil
Gas
Nuclear
Biomass
Other
renewables
Fuente: IEA Energy Technology Perspectives 2008
BLUE Map scenary: reducción global emisiones de CO2 en un 50% en 2050/2005
• US … 20% Wind by 2030 (1 % now)
• EU … 20% Renewable Energy by 2020
• China … 30 GW Wind by 2020
• India … 12 GW Wind by 2012
Europe´s commitment in the promotion
of renewables: Directive 20/20
Conventional Way of Interconnection
continued
Initiative of Interconnection
VLoad  K1 cos( )
  30 0
  90 0
0
0
0.005
0.01
0.015
0.02
0.025
0.03
0.035
0.04
200
0
-200
0
0.005
0.01
0.015
0.02
0.025
0.03
0.035
0.04
0
0.005
0.01
0.015
0.02
0.025
0.03
0.035
0.04
0
0.005
0.01
0.015
0.02
0.025
0.03
0.035
0.04
1
1
0
Pulses
0.5
0
0.005
0.01
0.015
0.02
0.025
0.03
0.035
0
15
10
0.4
5
0
0.5
0.04
Iload
Iload
Pulses
-200
Vs and Vload
200
0
0.005
0.01
0.015
0.02
0.025
0.03
0.035
0.04
0.2
0
Proposed Way of
Interconnection
Bridge Rectifier
AC Main Supply
Rectifier
ly
pp
Su
n ge
ai a
M olt
V
_
0
0
Firing angle
Controller
+
P
V
G
DC Voltage Source
C
iring
9
le >
Ang
Smoothing
Coil
A
AC load
Firing Pulses
(900 ££1800)
PV Panels
Photo
PV Panels
Circuit and Mathematical Model
Ig 
(Voc  Vg )
A  BV g  CVg
Pg  Vg I g 
2
Vg (Voc  Vg )
A  BV g  CVg
2
PV MODEL
PARAMETERS DETERMINATION
RL1= 23.8 
RL2=13.5 
RL3=4.3 
PV MODEL
Parameters Determination
I m1 
I m2 
I m3 
I m4 
(Voc  Vm1 )
A  BV m1  CVm1
2
(Voc  Vm 2 )
A  BV m 2  CVm 2
2
(Voc  Vm3 )
A  BV m3  CVm3
2
(Voc  Vm 4 )
A  BV m 4  CVm 4
2
PV Panels Characteristics
5
11:00 am
Ig (A)
4
9:00 am
3
2
3:00 pm
1:00 pm
1
0
0
5
Pg (W)
100
10
15
20
Vg (Volt)
(a)
25
30
35
40
30
35
40
11:00 am
9:00 am
50
0
1:00 pm
0
5
3:00 pm
10
15
20
Vg (Volt)
25
Firing Angle Controller
Block Diagram
DC Side Power
Maximum Power
Tracker
Desired Firing
Angle
900
1800
Firing Pulses
Insolation Level
Pulses
Generator
PCC Voltage
(a)
Maximum PVG
Power
Measured PVG Power
Pg, max
error
+
-
Out = k if error >
Out = 0 if Error
Out = - k if error < -
out
Output Conditionner
PPVG
1800
Gain
_____
S
900
Integrator
& Limiter
Firing angle
Insolation I
Corresponding
Level
Converter Of angle to
Voltage Level
AC Main
Voltage
Firing Pulses
Fi ring angle
(b)
Synchronized Sawtooth Generator
(c)
Comparator
Experimental Setup
Performance
(before Interconnection of PV Panels)
Performance
(after Interconnection of PV Panels)
Limitations & Drawbacks
(Of Current Experimental Setup)
• Equipment Ratings
• Low Power Factor
• Harmonics Generation
Harmonics Generation Solution
AC
Main Supply
(i.e Power Grid)
PW
Ps
is
iw
ih
PW
+
Controlled
Bridge Converter
Wind Driven
DC Machine
Ph
Controlled
Bridge Converter
Ppvg
P
pvg
ipvg
Active Power
Filter
-
+
PhotoVoltaic
Generator (i.e Solar
Pannels)
(f)
0.66
0.68
0.7
Iline1 (A)
0
-2
0.64
10
0
-10
0.64
10
0
-10
0.64
10
0
-10
0.64
0.66
0.66
0.66
0.68
0.68
0.68
0.66
0.68
time (s)
0.7
0.7
0.7
0.7
-20
0.93 0.94 0.95 0.96
2
0
-2
0.93 0.94 0.95 0.96
10
0
-10
0.93 0.94 0.95 0.96
10
0
-10
0.93 0.94 0.95 0.96
10
0
-10
0.93 0.94 0.95 0.96
time (s)
Vs (V)
Is (A)
-20
0.64
2
0
Iline1 (A)
0
0.93 0.94 0.95 0.96
20
Iline2 (A)
Vs (V)
0.7
Is (A)
0.68
Iline2 (A)
Is (A)
0.66
200
0
-200
Ih & Ihref (A) Iline (A)
(e)
0.64
20
200
0
-200
Ih & Ihref (A) Iline (A)
(d)
Iline1 (A)
(c)
Iline2 (A)
(b)
200
0
-200
Ih & Ihref (A) Iline (A)
(a)
Vs (V)
Harmonics Generation Solution
Continued
1.16
20
1.18
1.2
1.18
1.2
-2
1.16
1.18
1.2
10
0
-10
1.16
1.18
1.2
10
0
-10
1.16
1.18
1.2
1.18
time (s)
1.2
0
-20
1.16
2
0
10
0
-10
1.16
Conclusions
• Interconnecting PVG source to a main AC supply was
investigated.
- The interconnection was done using a bridge rectifier. The
bridge rectifier was operated in an “inverter mode of operation”.
• Quite encouraging results were reached when taken under a
random insolation level. For an almost 130 W power required
by an ac load connected at the ac side of the bridge, the PVG
source contributed nearly 69.23 % of such power while the
main ac supply supplied the rest 33.77 % of power to the AC
load.