Solar PV – Balance of Systems

Madhavan Nampoothiri, IPLON GmbH

Meenakshi College, Chennai – February 2, 2012

Overview

• About iPLON GmbH• What is BOS?• Inverters• Mounting structures• Cables and connectors• Performance monitoring systems• Conclusion

About iPLON GmbH

German company with a strong Indian connection!

- Founded by Mr. Victor Thamburaj

- Alumnus of IIT Madras

- Worked in senior positions in German companies before starting iPLON

- Trained Electrical Engineer

The Indian connection

Schwäbisch Hall – A charming small town in South Germany

iPLON GmbH- Total lifecycle management

of Solar farms

- Installed more than 150 MWp in Germany and Italy

- Located in Schwäbisch Hall, North of Stuttgart

- India office in Chennai

Products and Services of iPLON

EPC

Solar Infranet(iAT, iMT, Internet connectivity)

String Monitoring

Inverter Monitoring

Environ-mental Sensors Monitoring

AC Power Metering (Evc. Point)

Trans-former / Grid connected comp. Monitoring

System Engineering Reviews Document. Project Mgmt.

Services O&M

Comissioning

Training & Workshops

Application and Application Support

What is BOS?

Everything in the “gap” between PV modules & the Grid

PV System

PV modules – The most visible part of a PV system

BOS – The unglamorous cousins of PV modules

– Power Electronics• Inverters

– Mounting Structures• Racking - Fixed tilt• Tracking systems

– Single axis– Dual axis

– Cables and connectors– Performance monitoring systems

• Weather stations• Local monitoring(SCADA – PC based)• Remote monitoring(Web based)

PV SystemPV modules

Inverter

MountingStructure

Inverters

DC to AC Converter

What Inverters are good for..

• Converting DC to ACFancy Fourier

Transformation

Inverter features

• High Efficiency• Low standby loss• Frequency regulation(50 Hz in India)• Harmonic distortion control• Ease of servicing• Reliability• Power correction factor

Type of Inverters

• Central Inverters(Dominant in emerging markets)

• String Inverters(Preferred in European markets)

• Micro- Inverters(Still in development)

Central-Inverters vs.

String-Inverters

PVModul

e

Field Termin

al

Field Termin

al

Central Inverter

Central Inverter

Still on DC Level!

PVModule

Inverter

Inverter

Grid

Already on AC level!

String Inverter

Typical String-Inverters

Source: SMA, Power One, Kaco

Typical Technical Data

Source: SMA

Typical Central Inverters

Source: SMA, Power One

Typical Technical Data

Source: SMA

Topology

• Two options:–Design for „Central Inverters“–Design for „String Inverters“

Central Inverters

Central Inverters

String Inverters

String Inverters

ComparisonCentral String

Costs + +

Maintenance + ++

Size of plant Large scale only Small to very large

Efficiency + ++ (individual MPP tracking)

MPP Tracking O ++

Cables O ++

Mounting Structures

Modules’ long lasting companion

The support..

Mounting structures

• The structuring that supports the modules• Typically aluminum, galvanised iron• Should be corrosion resistant• Choose depending on soil, wind and weather

conditions!• Overwhelming majority : Fixed tilt• Rare: Single or double-axis trackers

Mounting Structures

• Fixed Tilt• Single Axis• Double Axis

Fixed tilt in Open Areas

Source: Schletter

Fixed tilt in Open Areas

Source: Schletter

Fixed tilt in Open Areas(Adjustable)

Source: Schletter

Tracking systems

Type of Tracking systems– Manually operated

– Motor operated• Single Axis• Dual axis

Manually operated

Available in both single axis and dual axis modes

Motor Operated

Source: Linak AS

Motor Operated

Source: Linak AS

Single axis

Dual axis

Cable and Connectors

The electricity carriers

Cables

Source: LAPP

Source: Amphenol

Source: MC

Source: MC

Connectors

Performance monitoring systemsOperation and Maintenance

Remote Monitoring

• Remote Monitoring– Gain insights into string current– String voltage– Inverter performance– Error-messages– Weather conditions

Weather measurement

• Energy output directly related to ambient conditions like

– Amount of sunlight(Irradiation)

– PV Module temperature

– Ambient temperature

Irradiation sensors

Module and ambient temperature meaurement

Data logging and energy metering

iPLON Systems

Performance Monitoring Systems

– Weather stations– Local monitoring(SCADA – PC based)– Remote monitoring(Web based)

PERFORMANCE RATIO

Performance Ratio

• Performance Ratio = Most important factor of a Solar PV System!– Performance independent from weather condition– True efficiency of the plant

Installation

Concept – to - reality

Installation – Also part of BOS

– Engineering and Design– Project Management– Civil work

– Laying foundation for mounting structures and installation of modules on mounting structures

– DC/AC cabling– Transformer and switch yard construction

Conclusion

Appendix

• Resources– SMA.com?– Sunchaser.com?– Others?

Typical Technical Data(String Inverter)

Source: Power One

Typical Technical Data(String Inverter)

Source: Kaco

Typical Technical Data(Central Inverter)

Source: Power One