Atec Elgar-ETS Series - Manual

858.458.0223 [email protected]
Elgar ETS TerraSAS 1kW-1MW
• Low output capacitance
• High bandwidth up to 30kHz
• High resolution I-V curve simulates static and
dynamic conditions
• Designed for high speed Maximum Power Point
Tracking (MPPT)
• Can be integrated into a multi-channel system for
higher power testing
• Energy Harvest and Oscilloscope measurements
built in. *
• Low voltage, high bandwidth version for DC Power
Optimizers
Standalone TerraSAS Photovoltaic Simulator
For microgrids, energy storage, and inverter test
applications, the TerraSAS™ series photovoltaic
(PV) simulators are specifically designed to
emulate the dynamic electrical behavior of a
terrestrial PV solar array. They offer low output
capacitance and high closed loop bandwidth to
keep up with the advanced Maximum Power
Point Tracking (MPPT) algorithms used in today’s
grid-tied inverters.
The Embedded TerraSAS (ETS) is a high
performance solution in a small form factor
that combines an agile power supply with
an innovative I-V curve generator in a single
standalone unit.
• ETS 600 / 1000: For isolated and non-isolated
string inverters up to 1000Vdc Voc.
• ETS 60 / 80 / 150: For use with micro-inverters
or DC optimizers up to 150Vdc Voc
Application
Many solar inverters generate AC ripple on their
DC input, which is connected to the photovoltaic
array. For single phase inverters, the frequency
of this ripple is twice the line frequency (120 Hz
for US models). The simulator’s power supplies
must not suppress this ripple as a function of
their regulation loop. An increasing number
of inverters (and virtually all micro-inverters)
accurately measure amplitude and phase of the
ripple voltage and current to quickly track the
MPP of the array. This approach allows tracking
the MPP at a much higher speed when compared
to conventional dithering techniques (also called
perturbate-and-observe). Faster tracking of the
MPP results in a much higher overall efficiency
in cloudy conditions, where the irradiance is
constantly changing. It is likely that all solar
inverters will use this approach in the near future,
since end users are very sensitive to the overall
efficiency of their solar energy installations. To
satisfy this requirement, the PV simulator must
be capable of reproducing the voltage / current
behavior of a solar array at the ripple frequency.
Most standard switching power supplies employ
very large output capacitors and inductors in
their output circuits and are unable to deliver the
required performance - regardless of the response
speed of the I-V curve controller. Elgar’s TerraSAS
line of PV simulators are based on high speed
versions of our standard products, where output
capacitors and other speed-limiting components
have been adjusted. This results in a speed
improvement of 10 times or better.
Proprietary features built into the PV controller
hardware and firmware, combined with our
high speed power supplies, deliver the required
performance. This technology was extensively
tested on micro-inverters and is ready to test
the next generation of inverters. The required
performance is delivered by high speed switching
power supplies and advanced Digital Signal
Processing techniques. In some conditions
traditional DC power sources using IGBT
technology do not meet MPPT response speed
requirements, depending on the MPPT principles.
Our power supplies use Power MOSFETs,
which typically switch ten times as fast as the
most recent IGBTs. Higher switching frequency
translates to smaller output capacitors and
inductors - which is the key to a successful high
speed power supply design
60-1000 V
115
208 400 480
* - Available Q4 2013
291
AMETEK
Programmable Power
9250 Brown Deer Road
San Diego, CA 92121-2267
USA
10252013