STEVAL-ISV005V1 Datasheet, PDF (1/4 Pages) STMicroelectronics – 250 W solar battery charger based on PV voltage-boost controller SPV1020, bypass diode SPV1001N and CC-CV controller SEA05

STEVAL-ISV005V1
250 W solar battery charger based on PV voltage-boost controller
SPV1020, bypass diode SPV1001N and CC-CV controller SEA05
Data brief
Features
■ PWM mode DC-DC boost converter
■ Duty cycle controlled by the MPPT algorithm
with 0.2% accuracy
■ Operating voltage range 0-40 V
■ Overvoltage, overcurrent, overtemperature
protections
■ Built in soft-start
■ Up to 98% efficiency
■ Automatic transition to burst mode for
improved efficiency at low solar radiation
■ SPI interface
■ Output current limitation
■ RoHS compliant
Description
The STEVAL-ISV005V1 demonstration board is
mainly based on the SPV1020 device, a
monolithic DC-DC boost converter designed to
maximize the power generated by photovoltaic
panels independently of temperature and amount
of solar radiation.
The optimization of the power conversion is
obtained with an embedded logic which performs
the MPPT (max power point tracking) algorithm
on the PV cells connected to the converter.
One or more converters can be housed in the
connection box of the PV panels, replacing the
bypass diodes. Since the maximum power point is
locally computed, the efficiency at system level
will be higher than that of conventional topologies,
where the MPP is computed in the main
centralized inverter.
For a cost-effective application solution and
miniaturization requirements, the SPV1020
embeds the power MOSFETs for active switches
and synchronous rectification, minimizing the
number of external devices. Furthermore, the 4-
STEVAL-ISV005V1
phase interleaved topology of the DC-DC
converter renders unnecessary the use of
electrolytic capacitors, which would severely limit
the lifetime.
The SPV1020 works at fixed frequency in PWM
mode, where the duty cycle is controlled by the
embedded logic running a “Perturb & Observe”
MPPT algorithm. The switching frequency,
internally generated and set by default at 100
kHz, can be tuned externally, while the duty cycle
ranges from 5% to 90% with a step of 0.2%.
Safety of the application is guaranteed by
stopping the drivers in case of output overvoltage
or overtemperature.
The bypass diodes SPV1001N guarantee very
high application efficiency even when the PV
panel voltage is lower than the UVLO threshold of
the SPV1020 (6.5 V) and the connection is in
series consisting of two or more PV panels.
The SEA05 is connected to the output stage of
the application and is used to implement the
output current limitation (not available with the
SPV1020 alone) through the current sensing
resistors R9 and R10.
November 2011
Doc ID 022232 Rev 1
For further information contact your local STMicroelectronics sales office.
1/4
www.st.com
4