Method and apparatus for multi phase shift power converter control
A method and apparatus for multi phase shift control of a power converter. In one embodiment, the method comprises controlling a phase shift between a left leg and a right leg of a first bridge of the power converter during operation of the power converter; and controlling a phase shift between the first bridge and a second bridge of the power converter during the operation of the power converter, wherein the phase shift between the left and the right legs and the phase shift between the first and the second bridges are controlled based on an input voltage of the power converter and a required output voltage of the power converter.
1. A method for multi phase shift control of a resonant power converter, comprising:
controlling a phase shift between a left leg and a right leg of a first bridge of the resonant power converter during operation of the resonant power converter; and
controlling a phase shift between the first bridge and a second bridge of the resonant power converter during the operation of the resonant power converter, wherein the phase shift between the left and the right legs and the phase shift between the first and the second bridges are controlled based on an input voltage of the resonant power converter and a required output voltage of the resonant power converter, and wherein the first bridge is a DC-DC switching bridge and the second bridge is a cycloconverter that provides AC output power, via an AC power terminal, from the resonant power converter when the resonant power converter operates as a DC-AC inverter, and wherein the second bridge comprises a first leg coupled in parallel with a second lea, the first leg comprising a first switch coupled in series with a second switch that is coupled in series with a first capacitor, the second leg comprising a third switch coupled in series with a fourth switch that is coupled in series with a second capacitor, and wherein (i) a first node of the AC power terminal is coupled between the second switch and the first capacitor, and (ii) a second node of the AC power terminal is coupled is coupled between the fourth switch and the second capacitor.
2. The method of claim 1 , further comprising:
determining a relationship between (a) the phase shift between the left and the right legs and (b) the phase shift between the first and the second bridges; and
operating the resonant power converter at an optimum operating point based on the relationship.
3. The method of claim 1 , wherein the second bridge generates a single-phase output.
4. The method of claim 1 , wherein the second bridge generates a three-phase output.
5. The method of claim 1 , wherein the resonant power converter is a bi-directional power converter.
6. An apparatus for power conversion using multi phase shift control, comprising:
a resonant power converter comprising:
a first bridge having a left leg and a right leg;
a second bridge; and
a controller for (i) controlling a phase shift between the left leg and the right leg of the first bridge during operation of the resonant power converter, and (ii) controlling a phase shift between the first bridge and the second bridge during the operation of the resonant power converter, wherein the phase shift between the left and the right legs and the phase shift between the first and the second bridges are controlled based on an input voltage of the resonant power converter and a required output voltage of the resonant power converter, and wherein the first bridge is a DC-DC switching bridge and the second bridge is a cycloconverter that provides AC output power, via an AC power terminal, from the resonant power converter when the resonant power converter operates as a DC-AC inverter, and wherein the second bridge comprises a first leg coupled in parallel with a second leg, the first leg comprising a first switch coupled in series with a second switch that is coupled in series with a first capacitor, the second leg comprising a third switch coupled in series with a fourth switch that is coupled in series with a second capacitor, and wherein (i) a first node of the AC power terminal is coupled between the second switch and the first capacitor, and (ii) a second node of the AC power terminal is coupled is coupled between the fourth switch and the second capacitor.
7. The apparatus of claim 6 , wherein the controller further (iii) determines a relationship between (a) the phase shift between the left and the right legs and (b) the phase shift between the first and the second bridges, and (iv) operates the resonant power converter at an optimum operating point based on the relationship.
8. The apparatus of claim 6 , wherein the second bridge generates a single-phase output.
9. The apparatus of claim 6 , wherein the second bridge generates a three-phase output.
10. The apparatus of claim 6 , wherein the resonant power converter is a bi-directional power converter.
11. A system for power conversion using multi phase shift control, comprising:
a DC source; and
a resonant power converter, coupled to the DC source, comprising:
a first bridge having a left leg and a right leg;
a second bridge; and
a controller for (i) controlling a phase shift between the left leg and the right leg of the first bridge during operation of the resonant power converter, and (ii) controlling a phase shift between the first bridge and the second bridge during the operation of the resonant power converter, wherein the phase shift between the left and the right legs and the phase shift between the first and the second bridges are controlled based on an input voltage of the resonant power converter and a required output voltage of the resonant power converter, and wherein the first bridge is a DC-DC switching bridge and the second bridge is a cycloconverter that provides AC output power, via an AC power terminal, from the resonant power converter when the resonant power converter operates as a DC-AC inverter, and wherein the second bridge comprises a first leg coupled in parallel with a second leg, the first leg comprising a first switch coupled in series with a second switch that is coupled in series with a first capacitor, the second leg comprising a third switch coupled in series with a fourth switch that is coupled in series with a second capacitor, and wherein (i) a first node of the AC power terminal is coupled between the second switch and the first capacitor, and (ii) a second node of the AC power terminal is coupled between the fourth switch and the second capacitor.
12. The system of claim 11 , wherein the controller further (iii) determines a relationship between (a) the phase shift between the left and the right legs and (b) the phase shift between the first and the second bridges, and (iv) operates the resonant power converter at an optimum operating point based on the relationship.
13. The system of claim 11 , wherein the second bridge generates a single-phase output.
14. The system of claim 11 , wherein the second bridge generates a three-phase output.
15. The system of claim 11 , wherein the DC source is a photovoltaic (PV) module.
16. The system of claim 11 , wherein the DC source is a battery.
17. The system of claim 11 , wherein the resonant power converter is a bi-directional power converter.