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Digital control description
4
UM1471
Digital control description
The overall control architecture requires three feedback signals for correct operation, input
panel current and input panel voltage are used for maximum power point tracking; the output
bus voltage is used for monitoring OV condition and to control the starting/stopping
procedure.
These signals are sent to the ADC inputs of the microcontroller, according to the pin
assignment of Figure 7, and in function of these values, two timers generate PWM output to
drive the full bridge power MOSFETs or disable the driving signals to turn off the module,
isolating the solar panel from the output bus. The duty cycle value is regulated by a
maximum power point tracking algorithm implemented by the STM32 microcontroller
(Figure 8).
Figure 8.
MPPT algorithm embedded on 32-bit microcontroller STM32
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12/15
Doc ID 022251 Rev 1