Power-packet-switching converter with sequenced connection to link inductor
Methods and systems for managing link voltages in a power converter, where single phase, three phase or universal systems can be used. Common mode management refers to shifting of voltages in a particular direction to perform transition between input and output ports, in addition to maintaining soft switching property. Voltages in power converters can be freely increasing and decreasing, and thus damage to the circuit can be caused if these voltages change are not controlled.
1. A method of operating a power-packet-switching converter, comprising the actions of:
a) connecting first and second lines of a first port, through first and second respective phase legs, to drive an inductor, and thereby increase the amount of energy stored in the inductor;
b) isolating the inductor, so that the inductor drives current into a capacitance which is paralleled with the inductor, to thereby change the voltage on the capacitor and on the inductor;
c) connecting first and second lines of a second port, through first and second respective phase legs each comprising bidirectional switching devices, to draw power from the inductor, under zero-voltage-switching conditions;
d) turning off said first but not said second phase leg of said second port, to fix the voltage of one terminal of the inductor, while the inductor changes the voltage differential across the capacitor;
e) turning off the second phase leg of said second port, while the inductor continues to change the voltage differential across the capacitor;
f) coupling power from the inductor, through one of said first and second phase legs of said second port, in combination with another phase leg, under zero-voltage-switching conditions; and
repeating steps a)-f) with reversed current direction.
2. A solar energy system which implements the method of claim 1 .
3. A power conversion system which implements the method of claim 1 .
4. A method of operating a power-packet-switching converter, comprising the actions of:
a) connecting first and second lines of a first port, through first and second respective phase legs each comprising two bidirectional switching devices, to drive an inductor and increase the amount of energy stored therein;
b) turning off said first phase leg but not said second phase leg, to fix the voltage of one terminal of the inductor, while said inductor drives current into a capacitor, which is connected in parallel with the inductor, to thereby change the voltage differential across the inductor;
c) turning off said second phase leg, while allowing said voltage differential to continue changing;
d) once the voltage differential stops changing, connecting third and fourth lines of a second port, through third and fourth respective phase legs each comprising two bidirectional switching devices, to thereby transfer polyphase power out to said second port.
5. A solar energy system which implements the method of claim 4 .
6. A power conversion system which implements the method of claim 4 .