Method and apparatus for a leakage energy recovery circuit
View Patent ↗A method and apparatus for recovering leakage energy during DC power to AC power conversion. The apparatus comprises a leakage energy recovery circuit for storing leakage energy from a transformer and selectively coupling stored leakage energy to an input of the transformer.
1. An apparatus for recovering leakage energy during DC power to AC power conversion, comprising:
a leakage energy recovery circuit for storing the leakage energy from a transformer and selectively coupling stored leakage energy to an input of the transformer, wherein the leakage energy recovery circuit comprises a storage circuit for storing the leakage energy and a transfer circuit for selectively coupling the leakage energy to the input when a monitor voltage satisfies a threshold.
2. The apparatus of claim 1 , wherein the storage circuit generates the monitor voltage in accordance with an amount of the stored leakage energy.
3. The apparatus of claim 2 , wherein the storage circuit comprises a voltage divider for generating the monitor voltage.
4. The apparatus of claim 1 , wherein the transfer circuit comprises:
a switch for causing (i) the leakage energy to be stored when the switch is in a first state and (ii) the leakage energy to be coupled to the input when the switch is in a second state; and
a driving circuit for driving the switch to the second state when the monitor voltage satisfies the threshold.
5. The apparatus of claim 4 , wherein the switch remains in the second state for a period of time determined by the driving circuit.
6. The apparatus of claim 1 , wherein the threshold is determined in accordance with an input voltage of the transformer, an output voltage of the transformer, and a ratio of the transformer.
7. The apparatus of claim 1 , further comprising a bypass capacitor, wherein the stored leakage energy is coupled to the bypass capacitor.
8. A method for recovering leakage energy during DC power to AC power conversion, comprising:
storing the leakage energy generated by a transformer,
generating a monitor voltage for indicating an amount of stored leakage energy;
comparing the monitor voltage to a threshold; and
coupling the stored leakage energy to an input of the transformer when the monitor voltage satisfies the threshold.
9. The method of claim 8 , wherein the storing leakage energy comprises operating a switch in a first state.
10. The method of claim 9 , wherein the coupling the stored leakage energy comprises operating the switch in a second state.
11. The method of claim 10 , further comprising operating the switch in the second state for a predetermined period of time.
12. The method of claim 8 , further comprising determining the threshold in accordance with an input voltage of the transformer, an output voltage of the transformer, and a ratio of the transformer.
13. An inverter for converting DC power to AC power, comprising:
a transformer for converting a first DC power to a second DC power;
an H-bridge for converting the second DC power to the AC power; and
a leakage energy recovery circuit for storing leakage energy from the transformer and selectively coupling stored leakage energy to an input of the transformer, wherein the leakage energy recovery circuit comprises a storage circuit for storing the leakage energy and a transfer circuit for selectively coupling the leakage energy to the input when a monitor voltage satisfies a threshold.
14. The inverter of claim 13 , wherein the storage circuit generates the monitor voltage in accordance with an amount of the stored leakage energy.
15. The inverter of claim 13 , wherein the transfer circuit comprises:
a switch for causing (i) the leakage energy to be stored when the switch is in a first state and (ii) the leakage energy to be coupled to the input when the switch is in a second state; and
a driving circuit for driving the switch to the second state when the monitor voltage satisfies the threshold.
16. The inverter of claim 15 , wherein the switch remains in the second state for a period of time determined by the driving circuit.
17. The inverter of claim 13 , wherein the threshold is determined in accordance with an input voltage of the transformer, an output voltage of the transformer, and a ratio of the transformer.
18. The inverter of claim 13 , wherein the at least one inverter further comprises a bypass capacitor, wherein the stored leakage energy is coupled to the bypass capacitor.