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The charge from the high voltage cell is pumped into the inductor and then discharged into the low voltage cell by using the buck-boost converter.
The charge is transferred from cell 1 to cell 2 by switching the MOSFETS sw1 and sw2. in the following manner.
SW1 is closed, allowing charge from cell 1 to flow into the inductor with current I-charge. Once the inductor is fully charged the switch SW1 is opened and the switch sw2 is closed.
The inductor is fully charged and will reverse its polarity and begin to discharge. Charge from the inductor flows into cell 2 with current I-discharge.
Once the inductor is fully discharged the switch SW2 is opened and the switch SW1 is closed to repeat the process.
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