Solar Inverters &Battery Energy Storage
Systems (BESS)
Alternative Energy1Index
Title

Slide #

Overview and market trends▪ Solar Inverter and Battery Energy Storage System(BESS) architectures

3▪ Types of solar inverter topologies and applications

4▪ General market trends and drivers

5▪ Summary of Littelfuse solutions for solar inverters and BESS

5

Types of Solar inverters▪ Microinverter

8-9▪ Power optimizer

10-11▪ String inverter

12-13▪ Multi-string inverter

14-15▪ Central inverter

16-19

Battery Energy Storage System(BESS)▪ BESS architecture for residential and commercial

21-22▪ BESS architecture for large industrial and utility scale

23-24

Supplementary slides▪ Safety standards for solar inverter and battery energy storage system (BESS)

25▪ Littelfuse collaterals

26

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Solar Inverter andBattery Energy Storage System(BESS) architectures
AC coupled solar system

PV array

BESS*

Solar
inverter(DC-AC)

DC coupled solar system
PV array

Step-uptransformer

DC link

Solar
inverter(DC-AC)

Step-uptransformer

BESS*

Bi-directional
inverter(DC-AC)

Chargecontroller(DC-DC)

FeaturesFeatures

Two inverter: Bi-directional inverter with battery and a solar inverter

Single inverter to power loads

Offers higher flexibility. Easier installation, especially for retrofits. Get tokeep grid-tied inverter

Not ideal for retrofits. Required to replace existing inverter and in manycases PV array wiring need to be reconfigured

Less efficient as the energy used by batteries is inverted multiple times.
Multiple components: Multiple MV transformers, inverters, etc.

Higher efficiency as the power is not inverter multiple times. Fewercomponents. Short cables between BESS and PV reduces losses

Cost effective if there is an existing PV system

High cost and complex installatioon with an existing PV system

Acronyms:
BESS: battery energy storage system
AC:alternate current

PV:
DC:

photo voltaic
direct current

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Types of solar inverter topologies and applications
Micro inverter

String inverter*

Multi-string inverter

Central inverter…

…

MPPT-1

Combiner box

MPPT-2DC-AC
inverter

FeaturesFeatures

Centralinverter

FeaturesFeatures

Rated up to 300 W range

Rated 1 kW to 10 kW range

Rated 30 kW – 200 kW

Rated up to a few mega watt range

Primarily used in residential buildings

Residential

Commercial, industrial, and utility

MV utility grid, PV farms

Output voltage: 230 VAC

Output voltage: 230 VAC

Output voltage: 400 VAC

Output voltage: 400 VAC – 690 VAC

Single phase

Single phase

Three phase

Three phase

Self consumption

Mostly for self consumption, fed to grid

Self consumption; distribution networks

MV distribution networks* Power Optimizers or DC Optimizers are DC-DC converters with MPPTs (maximum power point tracking )used along with string inverters to increase efficiencyof overall solar system. The MPPT function is performed at the level of each photo-voltaic panel, so that they all operate at their maximum power point.

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Solar inverter and battery energy storage market is set
to grow at a CAGR of 15.6% and 33.9% respectively
Market trends and drivers

Solar inverter market

The global solar inverter market is projected to grow from
USD 8.6 billion in 2020 to USD 17.6 billion by 2025
The below 10 kW segment held the largest share of the invertermarket in 2019. Inverters with power rating below 10 kW aresuitable for use in the residential and commercial sectors
The solar inverter market in APAC projected to grow at the highest
CAGR from 2020 to 2025. The rising demand for inverters from theresidential, automotive, and PV plants in India, China, and Japan is
fueling the growth of the solar inverter market in APAC.

Battery energy storage market

Battery energy storage system market is expected to grow from
USD 2.0 billion in 2018 to reach USD 8.5 billion by 2023. APAC todrive the highest growth

Utilities to hold largest size of the battery energy storage system
market . Residential energy storage market too grow at 22.8%(3 – 6 kW segment to grow fastest )Source: Solar inverter, Energy storage systems
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Littelfuse solutions for Solar Inverterand Battery Energy Storage System(BESS)
Input protection

Output protection⚫ Fuse⚫ MOV⚫ Surge protection device⚫ Ground fault relay⚫ Fuse⚫ MOV⚫ Surge protection devices⚫ AC earth fault relay

DC-DC converter

Auxiliary power supply⚫ MOSFET⚫ Gate driver⚫ TVS diode⚫ Temperature indicator⚫ MOSFET⚫ Gate driver⚫ TVS diodeDC-AC inverter

BESS⚫ IGBT module⚫ Gate driver⚫ TVS diode⚫ Temperature indicator⚫ UL Class fuse, High-speed fuse
⚫ TVS diode, Diode array⚫ Arc flash relay⚫ MOSFET/IGBT module⚫ Temperature sensor⚫ Surge protection device⚫ Ground fault relay

Communication interface⚫ Diode array⚫ Multilayer varistors

BESS: Battery Energy Storage System
Protect

Control

Sense

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Solar inverters

Click on the product series inthe table below for more info

Microinverter block diagram
DC-DC converter

Input filter
Solar
panel

Highfrequency
inverterDC-AC
Gate
driver1

2
Highfrequencytransformer

Rectification

Lowfrequency
inverter
DC-AC

5

3

4
Outputfilter andprotection

230 VAC
Single
phase

5

Gate
driver2

6

Auxiliary
power supply

1

MCU

Power
Data/Signal

Microinverter

Acronyms:
MLV: multilayer varistor
MOV: metal oxide varistor

TVS:
MCU:

transient voltage suppressor
microcontroller unit

TVS diode

SMCJ, SMDJ

NTC

RA, RB, KR

SiC Schottky
Diodes

650V diodes
Ultra-junction X2

SMBJ

MOV

TMOV, UltraMOV, LA

Cartridge fuse215

Gate driver

IXD_6xxSITVS diode

SMBJ

6

Diode array or
MLV

SP3130,
MLA,MHS

7

Diode array

SP712
SP2555NUTG

5Legend:Control unit

Trench Gate Gen2,TVS diode4
Power line
communication

MOSFET

600-650 V Trench

37

Product series

MOSFET or
IGBT

Wireless,
BLE, Zigbee

Wiredinterface

Technology

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Potential Littelfuse products for microinverter
Technology

1

2

3

Function in application

SeriesTrench Gate Gen2

Benefits

Features

High power density; easy to mount; space saving

Ultra low on-resistance RDS; high current handlingcapability; fast body diode

MOSFET

High frequency switching

TVS diodeProtects MOSFET from voltage
transients

SMCJ, SMDJ

Enables compact design; improves system
reliability

3000 W PPPM capability; low profile package

NTC

High temperature detection due to highsunlight, power component failure, etc.

RA, RB, KR

Provides safe operation of PV panels; smaller
footprint saves space

Surface mountable; small form-factor

SiC Schottky Diodes

Used for rectification

650V diodes

Reduces switching losses; increases systemefficiency, reliability and thermal management

High surge capability; negligible reverse recovery
current; Tj = 175 °C

Ultra-junction X2

High efficiency; high power density; easy to mount

MOSFET or
IGBT

Convert DC voltage from PV panel toAC line voltage

Ultra low on-resistance RDS(ON) and gate charge
Qg; low package inductance; dv/dt ruggedness

600-650 V Trench

Reduced thermal resistance; low energy losses;
fast switching

Low Vsat, low Eon/Eoff, high surge current capability;
positive thermal co-efficient of VCE(sat)Enables compact design; improves system
reliability

600 W peak pulse power capability; excellent
clamping capability; small footprint

TVS diodeProtect IGBTs from an event oftransient overload

SMBJ

MOV

Protects power unit from voltage
transients and lightning

TMOV, UltraMOV, LA

Reduces customer qualification time by complying
with third-party safety standards

High energy absorption capability:
40–530 J (2 ms)

Cartridge fuse

Protects from overcurrent events

215

Reduces customer qualification time by complying
with third-party safety standards

High breaking capacity; meets theIEC 60127-2

Gate driver

Controls the switching MOSFETs

IXD_6xxSIDual outputs provide space-efficient design;high immunity to latch-up; rise/fall times <10 ns

Tight tolerance; small form factor;
fast thermal response

TVS diodeProtect gate driver from event oftransient overload

SMBJ

Enables compact design; improves system
reliability

600 W peak pulse power capability; excellent
clamping capability; small footprint

6

Diode array or
MLVProtects ICs from ESD through wirelessinterface

SP3130,
MLA,MHS

Smaller form-factor and multi-line protection
enables ease of design

Low capacitance of 1.0 pF per I/O

7

Diode array

Protection of data lines from ESD/EFT
and surges events

SP712
SP2555NUTG

Minimizes signal distortion; reduces voltage
over-shoot, and simplified PCB design

Low capacitance of 2.5 pF; low leakage current of
0.1 μA ; small form factor

4

5

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Power optimizer block diagram
Technology

Product series

MOSFET

Trench Gate Gen2,TVS diode

SMCJ, SMDJ

NTC

RA, RB, KR

Gate driver

IXD_6xxSITVS diode

SMBJ

3

Diode array or
MLV

SP3130,
MLA,MHS

4

Diode array

SP712
SP2555NUTG,SM712

1
Buck-Boost
DC-DC
converter

Input filter
Solar
panel

Stringinverter

Outputfilter andprotection

230 VAC
Single
phase

1

2
Gate
driver2

3
Auxiliary
power supply

Wireless,
BLE, Zigbee

4
MCU
Legend:Power
Data/Signal

Wiredinterface

PLC, RS-485,
Ethernet

Control unit
Power optimizer

Acronyms:
MLV: multilayer varistor
NTC: negative temperature coefficient

TVS:
MCU:

transient voltage suppressor
microcontroller unit

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Potential Littelfuse products in power optimizer
Technology

Function in application

SeriesBenefits

Features

High power density; easy to mount;space saving

Ultra-low on-resistance RDS; high current handlingcapability; fast body diode

SMCJ, SMDJ

Enables compact design; improves system
reliability

3000 W PPPM capability; low profile package

High temperature detection due to highsunlight, power component failure, etc.

RA, RB, KR

Provides safer operation of PV panels; smaller
footprint saves space

Surface mountable; small form-factor

Gate driver

Controls the switching MOSFETs

IXD_6xxSIDual outputs provide space-efficient design; highimmunity to latch-up;
rise/fall times <10 ns

Tight tolerance; small form factor;
fast thermal response

TVS diodeProtect gate driver from event oftransient overload

SMBJ

Enables compact design; improves system
reliability

600 W peak pulse power capability; excellent
clamping capability; small footprint

3

Diode array or
MLVProtects ICs from ESD through wirelessinterface

SP3130,
MLA,MHS

Smaller form-factor and multi-line protection
enables ease of design

Low capacitance of 1.0 pF per I/O

4

Diode array

Protection of data lines from ESD/EFT
and surges events

SP712, SP2555NUTG,
SM712

Minimizes signal distortion, reduces voltage
overshoot, and simplified PCB design

Low capacitance of 2.5 pF; low leakage current of
0.1 μA ; small form factor

1

MOSFET

High frequency switching

TVS diodeProtects MOSFET from voltage
transients

NTC

Trench Gate Gen2

2

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String inverter block diagram1
SolarpanelsInput
protection
and filter

3

2
DC-DC
boost with
MPPT

PVstringGate
driverOutputfilter andprotection

InverterDC-AC

5

Product series

230 VAC
Singlephase

MOV

UltraMOV, LA, SM20

MOSFET

Trench Gate Gen2TVS diode

SMCJ, SMDJSiC Schottky
diode650V diodes

NTC

RA, RB, KR

MOSFET or
IGBTUltra-junction X2
600-650 V Trench

TVS diode

SMBJ

MOV

TMOV, UltraMOV, LA

Fuse

Class J, Class RK5,
KLKD

Gate driver

IXD_6xxSI, IX4351NE

TVS diode

SMBJ

6

Diode array or
MLV

SP3130,
MLA,MHS

7

Diode array

SP712, SM712
SP2555NUTG

1

2

5

Gate
driverTechnology

4

6
Wireless, BLE,
ZigbeeAuxiliary
power supply

3

4

7
Wired
interface

MCU

RS-485/Ethernet

5

Legend:Power

Control unit

Data/Signal

String inverter

Acronyms:
MPPT: maximum power point tracking
MOV: metal oxide varistor

TVS:
MCU:

transient voltage suppressor
microcontroller unit

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Click on the product series inthe table below for more info

Potential Littelfuse products for string inverter
Technology

SeriesBenefits

MOV

Protects from voltage transients andlighting surges

UltraMOV, LA, SM20

Reduces customer qualification time by complying
with third-party safety standards

High energy absorption capability:
40–530 J (2 ms)

MOSFET

High frequency switching

Trench Gate Gen2High power density; easy to mount; space-saving

Ultra-low on-resistance RDS; high current handlingcapability; fast body diodeTVS diodeProtects MOSFET from voltage
transients

SMCJ, SMDJ

Enables compact design; improves system
reliability

3000 W PPPM capability; low profile package

SiC Schottky diode

Used for rectification

650V diodes

Reduces switching losses; increases systemefficiency, reliability and thermal management

High surge capability; negligible reverse recovery
current; Tj = 175° C

NTC

High temperature detection due to highsunlight, power component failure, etc.

RA, RB, KR

Provides safe operation of PV panels; smaller
footprint saves space

Surface mountable; small form-factor

MOSFET or
IGBT

Convert DC voltage from PV panel toAC line voltage

Ultra-junction X2

High efficiency; high power density; easy to mount

Ultra low on-resistance RDS(ON) and gate charge
Qg; low package inductance; dv/dt ruggedness

600-650 V Trench

Reduced thermal resistance; low energy losses;
fast-switching

Low Vsat, low Eon/Eoff, high surge current capability;
positive thermal coefficient of VCE(sat)

TVS diodeProtect IGBTs from an event oftransient overload

SMBJ

Enables compact design; improves system
reliability

600W peak pulse power capability; excellent
clamping capability; small footprint

MOV

Protects power lines from voltage
transients and lightning surges

TMOV, UltraMOV, LA

Reduces customer qualification time by complying
with third-party safety standards

High energy absorption capability:
40–530 J (2 ms)

Cartridge fuse

Protects from overcurrent events

215

Reduces customer qualification time by complying
with third-party safety standards

High breaking capacity; meets theIEC 60127-2

Gate driver

Controls the switching MOSFETs

IXD_6xxSI, IX4351NE

TVS diodeProtect gate driver from event oftransient overload

SMBJ

Enables compact design; improves system
reliability

600W peak pulse power capability; excellent
clamping capability; small footprint

6

Diode array or MLV

Protects ICs from ESD events

SP3130, MLA, MHS

Smaller form-factor; offers design flexibility

Low capacitance of 1.0 pF per I/O

7

Diode array

Protection of data lines from ESD/EFT
and surges events

Minimizes signal distortion, reduces voltage
overshoot, and provides a simplified PCB design

Low capacitance of 2.5 pF; low leakage current of
0.1 μA ; small form factor

1

2

3

4

5

Function in application

SP712, SM712
SP2555NUTG

Features

Dual outputs provide space-efficient design; highTight tolerance; small form factor;
immunity to latch-up; rise/fall times less than 10 ns fast thermal response

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Multi-string inverter block diagram1
SolarpanelsInput
protection

1

1
Solar
panelsDC-DC
Converter
with
MPPT

2
DC-DC
Converter
with
MPPT

Input
protection

Inverter
DC-AC

Line
filterGrid
relay

Outputprotection

GatedriverAuxiliary
power
supplyPower
Data/Signal

Multi-string
Inverter2

Fuse*

SPF, SPFISPD

SPD2 PV series

Wireless,
BLE, Zigbee

Wiredinterface

RS-485/
Ethernet

High Voltage Series

IGBT Module

MIXA, MIXG

High-speed fuse

PSR

TVS diode

SMBJ

Fuse

Class T, Class J

MOV orSPD

UltraMOV, LA, SM7
SPD type 2

SiC MOSFET or
MOSFET

LSIC1MO170E1000
High Voltage Series

Gate driver

IX4351NE

TVS diode

SMF

6

Diode array or
MLV

SP3130,
MLA,MHS

7

Diode array

SP712, SM712
SP2555NUTG

47transient voltage suppressor
microcontroller unit

LSIC1MO120E0120

1200 V diode5

Control unit

TVS:
MCU:

SiC MOSFET or
MOSFET**
SIC Diode**65* You do no need a fuse if there are only two PV strings per MPPT** Recommended for 1000 V PV inverter systems. 1500 V PV system needs
1700 V MOSFET or IGBT
Acronyms:
MPPT: maximum power point tracking
SPD: surge protection devices

400 VAC
Three
phase

3

MCU

Legend:Product series

4

3

2
DC-DC
converter
with
MPPT

Technology

1

...

Input
protection

...

...

Solar
panels2

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Potential Littelfuse products for multi-string inverter
Technology

SeriesFuse

SPF, SPFISPD 2Provide equipment protection fromtransient overvoltage events lSPD2 PV series

12Function in application
Protect PV modules and conductors
from reverse overcurrent conditions

SiC MOSFET or
MOSFET*

Boost converter for high-frequency
switching

SiC Diode

Benefits

Features

Prevents power generation losses due to nuisance Meets UL and IEC standards; 1000 VDC, 1–30 A
ratings available; max interrupt rating 50 kA
tripping from changes in temperature
Withstand high-energy transients to prevent
disruption, downtime, degradation of equipment

Available in 1100 and 1500 Vdc; compact footprint;
capability to clamp and withstand transients

LSIC1MO120E0120

Optimized for high-frequency applications

Ultra-low output capacitance and on-resistanceHigh Voltage SeriesHigh power density; easy to mount; space-saving

Fast switching time; ultra-low RDS(on)1200 V diode

Reduces switching losses; increases systemefficiency, reliability, and thermal management

High surge capability; negligible reverse recovery
current; Tj 175 °C

MIXA, MIXG

Allows flow power consumption and fast response

Rugged design with thin wafer technology; lowgate charge; low EMI and competitive low VCE(SAT)

IGBT module

Switches power supplies

High-speed fuse

Protects semiconductor devices ininverter

PSR

Lower I2t performance allows for quick response
to protect devices from higher heat energy

550–1300 VAC, 500–1000 VDC, 40–2000 A

TVS diodeProtect IGBTs from an event oftransient overload

SMBJ

Enables compact design; improves system
reliability

600 W peak pulse power capability; excellent
clamping capability; small footprint

Fuse

Overcurrent or short circuit protection

Class T, Class J

MOV orSPD

Protects from power fluctuations orsurgesUltraMOV, LA, SM7
SPD type 2

Withstand high-energy transients to prevent
disruption, downtime, degradation of equipment

20 kA nominal interrupting rating and 50 kA
maximum interrupting rating

SiC MOSFET or
MOSFET

High frequency switching

LSIC1MO170E1000
High Voltage Series

Optimized for high-frequency; high power density;
easy to mount; space-saving

extremely low gate charge and output capacitance;
ultra low on-resistance; fast switching time

Gate driverto drive SiC MOSFETs and high power
IGBTs

IX4351NE

Eliminates the need for separate negative supply;
quick turn-on and turn-off of power SiC MOSFET

Separate 9 A peak source and sink outputs;
Internal negative charge pump regulator for

TVS diodeProtects SiC MOSFET from voltage
transient

Enables compact design; improves system
reliability

200W peak pulse power capability;
excellent clamping capability; low profile

6

Diode array or MLV

Protects ICs from ESD events

Smaller form-factor and ease of design

Low capacitance of 1.0 pF per I/O

7

Diode array

Protection of data lines from ESD/EFT
and surges events

Minimizes signal distortion, reduces voltage
overshoot, and provides a simplified PCB design

Low capacitance of 2.5 pF; Low leakage current of
0.1 μA; small form factor

3

4

5

SMF
SP3130, MLA, MHS
SP712, SM712
SP2555NUTG

Reduces damage to equipment caused by heating Extremely current-limiting; small footprint;
and magnetic effects of short circuit currents;
200 kA interrupting rating

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Central inverter block diagram
1... ...

Solar
panels2

3

PVcombiner
box

4

DC-DC
converterwith MPPT

690 VAC
Outputprotection Three
phase

DC-AC
inverter

7
DC earthfault relay*

1

Auxiliary
power
supply9
MCU

Product series

In-line fuse

SPXI

Fuse Holder

SPXV, SPNH, LFPXVSPDSPD2 PV series

SiC MOSFET or
MOSFET*

LSIC1MO120E0120;
High Voltage Series

SIC Diode*1200 V diode

IGBT module

MIXA, MIXG

High-speed fuse

PSR

TVS diode

SMBJ

Fuse

Class J,Class RK5, Class L

SPD

SPD type 22

3

AC earthfault relay

8

Solar
panels1

6Gate
drivers

Technology
54

Wireless,
BLE,
Zigbee5

10
Wiredinterface

RS-485,
Ethernet

Legend:Control unit

Power
Data/Signal

Central inverter* Recommended for 1000 V PV inverter systems. 1500 V PV system need 1700 V MOSFET** Ground Fault detectors should be used for resistive grounded systems. Suggest: EL731

Acronyms:
MPPT: maximum power point tracking
SPD: surge protection devices

TVS:
MCU:

transient voltage suppressor
microcontroller unit

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Potential Littelfuse products for central inverter
Technology

1

Function in application

SeriesBenefits

Inline fuse

Integrates into an in-line assembly
within a wire harness

SPXI

Fuse

Designed for protection PV systems

SPXV, SPNH, LFPXV

SPDProtection from transient overvoltage

SPD2 PV series

Prevents system disruption and downtime

Available in 1100 and 1500 Vdc; compact footprint

LSIC1MO120E0120

Optimized for high-frequency applications

Ultra-low output capacitance and on-resistanceHigh Voltage SeriesHigh power density; easy to mount; space-saving

Fast switching time; ultra-low RDS(on)1200 V diode

Reduces switching losses; increases efficiency,

High surge capability; negligible IRR; Tj 175 °C

MIXA, MIXG

Low power consumption and fast response

Rugged design; low EMI and low VCE(SAT)

Offers higher amperage protection; design
flexibility; save space, time, and money

Features50,000 A interrupting rating; UL recognizedOffers higher amperage protection; ease of design 50,000 A interrupting rating; fast acting fuse

2

SiC MOSFET or
MOSFET

3

Boost converter for high-frequency
switching

SiC Diode4

IGBT module

Switches power supplies

High-speed fuse

Protects semiconductor devices ininverter

PSR

Lower I2t performance allows for quick response
to protect devices from higher heat energy

550–1300 VAC, 500–1000 VDC, 40–2000 A

TVS diodeProtects IGBTs from transient overload

SMBJ

Enables compact design; improves system
reliability

600 W PPPM capability; low profile package

Fuse

Overcurrent or short circuit protection

Class J,Class RK5, Class L

Reduces damage to equipment caused by shortcircuit currents; compact design

Extremely current-limiting; small footprint;
200 kA interrupting rating

SPD

Protects from power fluctuations orsurgesSPD type 2

Withstand high-energy transients to prevent
disruption, downtime, and degradation

20 kA nominal interrupting rating and 50 kA
maximum interrupting rating

5

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Central inverter block diagram
1... ...

Solar
panels2

3

PVcombiner
box

4

DC-DC
converterwith MPPT

5690 VAC
Outputprotection Three
phase

DC-AC
inverter

7
DC earthfault relay*

1

Auxiliary
power
supplyProduct series

6

AC ground
fault relay

EL-731

7

DC ground
fault relay**

EL-731,SE-601

SiC MOSFET or
MOSFET

LSIC1MO170E1000
High Voltage Series

Gate driver

IX4351NE

TVS diode

SMF

9

Diode array or
MLV

SP3130,
MLA, MHS

10

Diode array

SP712, SM712
SP2555NUTG

6Gate
drivers8

AC earthfault relay

8

Solar
panelsTechnology

9
MCU

Wireless,
BLE,
Zigbee10
Wiredinterface

RS-485,
Ethernet

Legend:Control unit

Power
Data/Signal

Central inverter* Recommended for 1000 V PV inverter systems. 1500 V PV system need 1700 V MOSFET** Ground Fault detectors should be used for resistive grounded systems. Suggest: EL731

Acronyms:
MPPT: maximum power point tracking
SPD: surge protection devices

TVS:
MCU:

transient voltage suppressor
microcontroller unit

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Potential Littelfuse products for central inverter
Technology

Function in application

SeriesBenefits

Features6

AC ground
fault relay

Offers low-level ground-fault protection

EL-731

Adjustable trip setting provides a wide range of
low-level protection and system coordination

Adjustable pickup (30-5,000 mA);
Frequency range (0-90 Hz, 20-6,000 Hz)

7

DC ground
fault relays

Offers low-level ground-fault protection

EL-731,SE-601

Adjustable trip setting provides a wide range of
low-level protection

Adjustable pickup EL-731(30-5,000 mA); SE601(1-20 mA)

SiC MOSFET or
MOSFET

High frequency switching

LSIC1MO170E1000
High Voltage Series

Optimized for high-frequency applications; highpower density; easy to mount; space-saving

Extremely low gate charge and output capacitance;
ultra low on-resistance

Gate driverto drive SiC MOSFETs and high power
IGBTs

IX4351NE

Eliminates the need for separate negative supply;
quick turn-on and turn-off of power SiC MOSFET

Separate 9 A peak source and sink outputs;
Internal negative charge pump regulator

TVS diodeProtects SiC MOSFET from voltage
transient

SMF

Enables compact design; improves system
reliability

200W peak pulse power capability;
excellent clamping capability; low profile

9

Diode array

Protects ICs from ESD via wirelessinterface

SP3130

Smaller form-factor and multi-line protection easeof design

Low capacitance of 1.0 pF per I/O

10

Diode array

Protection of data lines from ESD/EFT
and surges events

SP712, SM712
SP2555NUTG

Minimizes signal distortion, reduces voltage
overshoot, and provides a simplified PCB design

Low capacitance of 2.5 pF; Low leakage current of
0.1 μA; small form factor

8

Littelfuse, Inc. © 2021

19

Battery Energy Storage System(BESS)

Click on the product series inthe table below for more info

BESS architecture for residential* and commercial
CMA 1

1

CMA n

Li-ionCell

Li-ionCell

Cellbalancing& control

Module 1

CMA 2

2

Control &protect
circuit1

Li-ionCell
Cellbalancing& control

Cellbalancing& control

DC-AC
inverter**Cellbalancing& control

3

Module X

CMA 2

Batterysystemcontroller

6

To
Utility2

3
4Li-ionCell

5Cell
balancing& control

3Technology

Product Series

Fuse

501A, 881

Temperature sensor

USP16673, RB

SMD orIn-line fuse

438A, 441A, 521

TVS diodeTPSMB, SZ1SMB,SZP6SMB

Diode array

AQ05C

TVS diode

TPSMA6L, SZ1SMA

Fuse

TLS, JLLN, CNN

High-speed fuse

PSR, PSXMOSFET

X3 Class

CMA n

Li-ionCell

2

1

Li-ion
Cell

4
CMA 1

5

Cell
balancing& control

Legend:Power

Battery rackData/Signal* Residential BESS has similar architecture, but the # of packs will be limited depending on the kVA ratings** Large industrial or utility scale BESS system, multiple battery racks are stacked together through a combiner box*** Arc Flash Relays are used in large commercial and higher applications

Acronyms:
CMA: Cell Module Assembly
BESS: battery energy storage system

Li-ion:TVS:

Lithium- ion
transient voltage suppressor

6

Gate driver

IXD_6xxSIHVDC contractor
relays

DCNxx

Arc flash relays***

AF0100DC Disconnect
Switch

LS6xx

Diode array

AQ24CANFuse

885

TVS diodeTPSMB,TPSMC
Littelfuse, Inc. © 2021

21

Click on the product series inthe table below for more info

Potential Littelfuse products for BESS
Technology

1SeriesBenefits

501A, 881

Excellent temperature stability and performancereliability; compact design

Fast response to fault current;
surface mount device

Features

TPSMC, SZ1SMC,
SZ1.5SMC

Excellent clamping capability; fast response time

Meets IEC standards for ESD protection

Fuse
TVS diodeTransient voltage suppression

Temperature sensor

Monitoring the system for optimal
charging conditions

USP16673, RB

Promotes robust operation; allows design flexibility Tight tolerance; ultra-thin

SMD or In-line fuse

Front end protection due to shorting of
power and sense line

438A, 441A, 521

Excellent temperature stability and performancereliability; compact design

Fast response to fault current;
surface mount device

TVS diodeProtects from transients induced due toassembly and maintenance of batteries

TPSMB, SZ1SMB,SZP6SMB

Excellent clamping capability; fast response time

Meets IEC standards for ESD protection

Diode array

Transient voltage suppression

AQ05C

Excellent clamping capability; fast response time

Meets IEC standards for ESD protection

TVS diodeProtects sensitive electronic ICs from
ESD, EFT, and voltage transient

Ensures reliability of the equipment without
performance degradation

Meets IEC standards for ESD protection;
low leakage current and clamping voltage

Fuse

Protects from short-circuits andoverloads between two packs

Reduces damage to equipment caused by shortcircuit currents; compact design

Extremely current-limiting; small footprint;
200 kA interrupting rating

2

3
4

Function in application
Protects cells/BMS components fromhigh-fault currents due to external shorts

TPSMA6L, SZ1SMA
TLS, JLLN, CNN

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22

Click on the product series inthe table below for more info

Potential Littelfuse products for BESS
Technology

56Function in application

SeriesBenefits

Features2

High-speed fuse

Short-circuit and overload protection
resulting due to high-power system

PSR, PSX

Lower I t performance allows for quick response
to protect devices from higher heat energy

High DC voltage rating up to 1500 VDC; extremely
fast-acting; compact form-factor

MOSFET

Output power control switch

X3 Class

Low power loss; design flexibility; high efficiency

Low RDS(ON); fast soft recovery body

Gate driver

Controls the switching MOSFETs

IXD_6xxSIDual outputs provide space-efficient design; highTight tolerance; small form factor;
immunity to latch-up; rise/fall times less than 10 ns fast thermal response

HVDC contractor
relaysThe main contactors connect anddisconnect the battery system

DCNxx

Allows a low voltage signal to switch the contacts
for a high voltage signal

Wide range of capabilities – can switch from 10’s ofamps to 1000’s of amps, and 10’s of volts to 1000’sof volts

Arc flash relays

Reduces damage by detecting the lightfrom an arc flash and rapidly tripping

AF0100

Fits into a wide range of arc-flash applications;monitor two arc-flash sensors; compact design

Input voltage: 100-240 VAC/VDC, 24-48 VDC, dual
sensor input; surface mounting DIN RAIL

DC Disconnect Switch

Help quickly break or resume the flowof current safely to prevent shock
hazards when trying to isolate circuits
or repair systems

LS6xx

energy-efficient, compact size; decreases
installation and maintenance time; increase
product reliability and longevity

High-level disconnection insulation; self-cleaning
blade contacts; meets UL 98B, UL 94, and IEC
60947-3 standards

Diode array

Protects from ESD, EFT, andvoltage transient

AQ24CAN

Ensures reliability of the equipment without
performance degradation

Meets IEC standards for ESD protection;
low leakage current and clamping voltage

Fuse

Protects cells and BMS components
from overcurrent

885

Compact design; ensures compatibility withhigh-temperature environment

Fast response to fault current;
surface mount device

TVS diodeTransient voltage suppression

Excellent clamping capability; fast response time

Meets IEC standards for ESD protection

TPSMB, TPSMC

Littelfuse, Inc. © 2021

23

BESS architecture for large industrial andutility scale (multiple battery racks connected)

Click on the product series inthe table below for more info

1

Li-ion Cells

CMA 2

CMA n

Li-ion Cell packLi-ion Cell pack

OutputProtect &control

2
Cell balancing &control

Cell balancing &control

3

Cell balancing &control

1

CMA 2

CMA n

Li-ion Cell packLi-ion Cell pack2
Cell balancing &control

Cell balancing &control

6
Battery
SystemController

38Module 2

CMA 1

Technology

Cell balancing &control

7

Battery rack 1…

1

Li-ion Cells

5

CMA 2

CMA n

Li-ion Cell packLi-ion Cell pack

Outputprotect &control

2
Cell balancing &control

Cell balancing &control3

Li-ion Cell pack

CMA 2

Cell balancing &control

SPD (DC link)

SPD type 2

High-speed fuse

PSX, PSR

Ground fault relay

SE-601IGBT module

MIXA, MIXGFuseClass J,Class RK5, Class L

SPD (AC link)

SPD type 2

DC-AC
inverter

99Outputprotection

To
Utility

Mastercontroller

Li-ion Cell pack2
Cell balancing &control

PSX, PSR

Battery
SystemController

CMA nLi-ion Cell packCombinerbox

63

Cell balancing &control

Module 2

1

High-speed fuse

Cell balancing &control

4
CMA 1

8

Module 1

CMA 1

Product series

7

4

Li-ion Cell pack5

Module 1

CMA 1

Legend:Power
Battery rack N

Acronyms:
CMA: Cell Module Assembly
BESS: battery energy storage system

Data/Signal

Li-ion:TVS:

Lithium- ion
transient voltage suppressor

Littelfuse, Inc. © 2021

24

Potential Littelfuse products
for industrial and utility scale BESS
Technology

Function in application

Click on the product series inthe table below for more info

SeriesBenefits

Features

High-speed fuse

Short-circuit and overload
current protection

PSX, PSR

Lower I2t performance allows for quick response
to protect devices from higher heat energy

High DC voltage rating up to 1500 VDC extremely
fast-acting; compact form-factor

SPD (DC link)

Provides equipment protection fromtransient overvoltage events

SPD type 2

Withstands high-energy transients to prevent
disruption, downtime, and degradation

20 kA nominal interrupting rating and 50 kA
maximum interrupting rating

High-speed fuse

Short-circuit and overload
current protection for power
semiconductors

PSX, PSR

Lower I2t performance allows for quick response
to protect devices from higher heat energy

High DC voltage rating up to 1500 VDC; extremely
fast-acting; compact form-factor

Ground fault relay

Offers low-level ground-fault protection

SE-601

Provides a wide range of low-level protection;
adjustable trip delay allows quick protection ordelayed response

Adjustable pickup (1-20 mA); adjustable time delay(50 ms-2.5 s); CSA certified, UL Listed (E340889),
CE (European Union), C-Tick

IGBT module

Switches power supplies

Allows for low power consumption and fast
response

Rugged design; low gate charge;
low EMI and low VCE(SAT)Fuse

Overcurrent or short circuit protection

Class J,Class RK5, Class L

Reduces damage to equipment caused by shortcircuit currents; compact design

Extremely current-limiting; small footprint;
200 kA interrupting rating

SPD (AC link)

Protects from power fluctuations orsurgesSPD type 2

Withstands high-energy transients to prevent
disruption, downtime, and degradation

20 kA nominal interrupting rating and 50 kA
maximum interrupting rating

7

8

MIXA, MIXG

9

* Battery Energy Storage System
Littelfuse, Inc. © 2021

25

Safety standards for solar inverterand battery energy storage system (BESS)
Standard

Title

General scope

Region

UL 1741

Inverters, Converters, Controllers and Interconnection
System Equipment for Use with Distributed Energy
Resources

These requirements cover inverters, converters, charge controllers, andinterconnection system equipment (ISE) intended for use in stand-alone or
grid-connected power systems

North America

IEC 61683

Power conditioners – Procedure for measuring efficiency

This standard describes guidelines for measuring the efficiency of power
conditioners used in stand-alone and utility-interactive photovoltaic systems

GlobalIEC 62109-1

Safety of Power Converters for Use in Photovoltaic Power
Systems – Part 1: General Requirements

This part of IEC 62109 applies to the power conversion equipment (PCE) for
use in Photovoltaic (PV) systems where a uniform level of safety isnecessary. This standard defines the minimum requirements for the design
and manufacture of PCE for protection against fire, energy, electric shock,mechanical, other hazards, etc.

GlobalIEC 62109-2

Safety of Power Converters for Use in Photovoltaic Power
Systems – Part 2: Particular Requirements for Inverters

This Part 2 of IEC 62109 covers the particular safety requirements relevant to
DC to AC inverter products intended for use in photovoltaic power systems

GlobalUL 9540A

Standard for Test Method for Evaluating Thermal
Runaway Fire Propagation in Battery Energy Storage
Systems

This document evaluates the fire characteristics of a battery energy storage
system that undergoes thermal runaway

North America

EN 50524

Data Sheet and Name Plate for Photovoltaic Inverters

Data sheet and name plate for photovoltaic inverters. The intent of thisdocument is to provide minimum information required to configure a safe andoptimal system with photovoltaic inverters.

Europe

EN 50530

Overall Efficiency of Photovoltaic Inverters

This European Standard provides a procedure for the measurement of theaccuracy of the maximum power point tracking (MPPT) of inverters, which
are used in grid-connected photovoltaic systems.

EuropeLittelfuse, Inc. © 2021

26

Circuit Protection Selection Guide

Power Relay & Control Catalog

Click on images
to open the
catalog

Solar Protection White Paper

Additional information can be found on Littelfuse.com

Littelfuse, Inc. © 2021

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Manufacturing

Littelfuse, Inc. © 202028

Partner for tomorrow’s electronic systems
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PRODUCT PORTFOLIOCOMPLIANCE AND
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An industrial technology manufacturing
company empowering a sustainable,
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process to account for requirements
set by global regulatory authorities

APPLICATIONEXPERTISETESTINGCAPABILITIESOur engineers partner directly withcustomers to help speed up productdesign and meet their unique needs

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