Transcript Slide 1

String inverters for
commercial PV
applications
David Smith, November 2013
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Commercial PV projects: Main Drivers
Energy Harvesting
Product Reliability
Simple Installation &
Maintenance
Product Flexibility
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String Application - Considerations
PRO
CONS
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• High design flexibility for a
wide range of applications
• Ease of installation
• BoS Integration (DC combiner)
• No Panel level MPPT
• No panel level monitoring
String : optimizing energy harvesting
Double MPPT & Scanning Function
Double MPPT with
High-Speed algorithm
Flexibility
Harvesting
Different MPPs to be managed separately for a
better energy harvesting
Real “equal & independent MPPTs” for a unique
flexibility in designing your own PV field
Mpp1
High Dynamic Efficiency: less than 2 seconds to
find the MPP
Mpp2
MPPT Scanning Function
False Targets
Power
Real Pmax
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3
Vmin
Voltage
Running a preliminary scanning function all
over the input voltage range considerably
increases the MPPT algortithm’s
effectiveness
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String: design flexibility and efficiency
Wide input voltage range and
Flat efficiency curve
Operating DC input
voltage up to 970V
Flexibility
Harvesting
Longer strings = benefits with highVoc PV modules.
Flat efficiency curve
Inverter’s efficiency stays at very high
levels on a wide range of Vdc and Pac
values. This feature gives you a unique
design flexibility for your PV plant
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String: keeping an eye on reliability
Electrolyte-free technology,
no fans and IP65 enclosure
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Reliability
No electrolytic
capacitors and fans
IP65 enclosure
with rear heatsink
Removing two of the
main causes of
failures = reliability
TRIO = 10 year
warranty
The rear heatsink
allows performing an
easy maintenance
from the front of the
inverter
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Installation & Maintenance
String: making everything easier
Ease of installation & Maintenance
Installer-friendly
wall connection
system
The inverter’s wall
connection system has been
designed so that you’ll be
able to install your own
product just performing a
few easy on-site actions.
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Installation & Maintenance
Reducing Balance of System Costs
Installation & Maintenance
String Fuse
Protection
DC – AC
Switch
Surge
Protection
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Compliant with ECA/MCS Guide
to the Installation of PV
2.1.10 String Fuses
2.1.10.1 String fuse Selection
Compliant with ECA/MCS Guide
to the Installation of PV
2.1.12.2 Switch Disconnector
2.1.12.3 Array Switch Disconnector
Compliant with ECA/MCS Guide
to the Installation of PV
2.2.6 Surge Protection Measures
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String: Grid Management
Smart Grid ready
Flexibility
Inverter contributes to
grid stability and
control to increase grid
quality
Frequency control
Capability to select Active
power reduction and
Reactive power regulation
Voltage Control
= Smart grid ready
Power Factor Management
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A closer look at TRIO
Installation &
Maintenance
Compactness &
Flexibility
Basic version
-S2 version
-S2F version
-S2X version
Class II Protection
AC + DC Switch
String level monitoring
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Why Use TRIO?
High energy
harvesting
High reliability
Fast installation
Easy to use
Flexible PV
plant planning
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• High efficiency
• Wide input voltage range (up to 1000V)
• Double Independent MPPTs
• Fast and precise MPP tracking algorithm
• Natural Convection Cooling
• Electrolyte free (no electrolytic capacitors)
• IP65 environmental protection rating
• Detachable Wiring Box
• Graphic display
• Graphic display
• Remote connection
• Wide input voltage range (up to 1000V)
• 4 different options for the wiring box
• 20.0 and 27.6 kW models
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Balance of System cost reductions - <50kW
Hardware
£/W Price
Lower Cost/W
Installation + O+M
~30% reduction in comparison of Inverter(s)
+ BOS for 20kW-50kW systems.
+ 10 year standard warranty for TRIO
Install cost reduction - Integral DC + AC
Isolator, Fuse combiners + OVP
OPEX (Reduced Maintenance) - Inverter can
be replaced simply without qualified staff.
String level monitoring = Preventative O+M
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Lost Energy Detection Improves Performance
Harvesting
Before
• Commercial rooftop system
67%
PR
After
82%
PR
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• 4 years operation with Inverter-level only
monitoring.
• Converted to string level monitoring
50kWp Roof example
• Location: Burgess Hill,
Sussex, UK
• Installed: Spring 2012
• Inverters:
• TRIO-20.0-TL-OUTD-S2X
• TRIO-27.6-TL-OUTD-S2X
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1MWp Roof Project
• Location: Bridgewater,
Somerset, UK
• Installed: Summer 2013
• Inverters:
• TRIO-20.0-TL-OUTD-S2X
• TRIO-27.6-TL-OUTD-S2X
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5MWp Roof Project
• Location: Crewe,
Staffordshire , UK
• Installed: Spring 2013
• Inverters:
• TRIO-20.0-TL-OUTD-S2X
• TRIO-27.6-TL-OUTD-S2X
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UK based Technical Support, Service and Training
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