CogniPower Technology for Solar Inverters
CogniPower's new technology for improved efficiency and performance in power converters
will be of particular value for solar power converters and inverters. CogniPower is patenting
an entirely new way of controlling power converters that provides the ability to respond
instantly to changing conditions. These power converters are intrinsically stable so they can
be made to do exactly what would be best to do at any given instant. This behavior is very
different from that of conventional power converters which must find a compromise between
stability and responsiveness.
Conventional converters are challenged to be reliable over the wide range of conditions
encountered in solar applications. Both the input voltage and current will vary because of the
nature of photovoltaics. Efficient solar inverters need to perform power maximization. Solar
panels will produce their maximum output at one particular voltage level, depending on
conditions. Those conditions change with time, but they can also change as quickly as a
cloud can block the sun. Conventional converters are pushed to their limits under these
circumstances because they obtain regulation based on averages over time. When both the
input and output conditions are changing, the indefinite relationship of time and energy
destabilizes the feedback mechanism causing overshoot or undershoot.
CogniPower converters respond to energy, not time. That means they can correct
instantaneously, instead of only being correct on the average. Conventional converter control
is analogous to driving a car while looking out the rear window. That might work well
enough on a straight section of road, but not so well on curvy sections. CogniPower
predictive energy balancing allows the controls to look forward -- out the windshield. This
makes it easy to stay on the road. The intrinsic stability enabled by prediction changes what
is possible to achieve. The needs of the grid, or of storage batteries, can be decoupled from
the needs of the photovoltaic panels. The voltage and current at each panel can be optimized
to be independent of the output regulation. This maximization can be done without the
compromises required to tame conventional converters.
CogniPower's technology is scalable from solar battery chargers to the largest solar arrays.