Power converter topology
A power converter topology, comprising: a cascade connection of a first converter stage and a second converter stage; wherein the first converter stage comprises a current mode controlled pulse width modulation (PWM) converter having one or more pairs of switches forming a first switching bridge and an inductor connected to the output of the first switching bridge, the switching bridge generating a voltage V link ; and wherein the second converter stage is a resonant converter having a switching stage having one or more pairs of switches forming a second switching bridge across the voltage V link generated by the first converter stage and a resonant tank connected to the output of the second switching bridge, to generate a resonator output voltage; the topology further comprising a transformer to transform the resonator output voltage to a transformed output voltage and a rectifier to rectify the transformed output voltage to an output voltage V out , and wherein the duty cycle of the first switching bridge is varied according to a voltage derived from the value of the output voltage V out , and wherein the duty cycle of the second switching bridge is fixed at 50:50.
1. A power converter topology, comprising:
a cascade connection of a first converter stage and a second converter stage, wherein:
the first converter stage comprises a current mode controlled pulse width modulation (PWM) converter having one or more pairs of switches forming a first switching bridge and an inductor connected to an output of the first switching bridge, the first switching bridge configured to generate a voltage V link ; and
the second converter stage comprises a resonant converter with a switching stage having one or more pairs of switches forming a second switching bridge across the voltage V link and a resonant tank connected to an output of the second switching bridge, the second switching bridge configured to generate a resonator output voltage;
a transformer configured to transform the resonator output voltage to a transformed output voltage; and
a rectifier configured to rectify the transformed output voltage to an output voltage V out ;
wherein a duty cycle of the first switching bridge is based on a current derived from a value of the output voltage V out ; and
wherein a switching frequency of the second switching bridge is a fixed frequency and a duty cycle of the second switching bridge is fixed at 50:50.
2. The power converter topology of claim 1 , wherein the first converter stage comprises a buck PWM converter.
3. The power converter topology of claim 1 , wherein the first converter stage comprises a boost PWM converter.
4. The power converter topology of claim 1 , wherein the switching stage is a half-bridge switching stage.
5. The power converter topology of claim 1 , wherein the switching stage is a full-bridge switching stage.
6. The power converter topology of claim 1 , wherein the resonant tank is an LLC resonant tank.
7. The power converter topology of claim 1 , wherein the rectifier comprises two semiconductor switches.
8. The power converter topology of claim 1 , wherein the rectifier comprises four semiconductor switches.
9. The power converter topology of claim 7 , wherein the semiconductor switches are MOSFETs.
10. A power distribution circuit comprising:
a power supply;
one or more loads configured to be provided with power from the power supply; and
a power converter as claimed in claim 1 and configured to convert power from the power supply to power for the one or more loads.
11. The power distribution circuit of claim 10 , wherein the power distribution circuit represents a power distribution circuit on an aircraft.
12. A method of operating a power converter, comprising:
providing a cascade connection of a first converter stage and a second converter stage, wherein:
the first converter stage comprises a current mode controlled pulse width modulation (PWM) converter having one or more pairs of switches forming a first switching bridge and an inductor connected to an output of the first switching bridge, the first switching bridge configured to generate a voltage V link ; and
the second converter stage comprises a resonant converter with a switching stage having one or more pairs of switches forming a second switching bridge across the voltage V link and a resonant tank connected to an output of the second switching bridge, the second switching bridge configured to generate a resonator output voltage;
providing a transformer configured to transform the resonator output voltage to a transformed output voltage;
providing a rectifier configured to rectify the transformed output voltage to an output voltage V out ; and
varying a duty cycle of the first switching bridge based on a current derived from a value of the output voltage V out , wherein a switching frequency of the second switching bridge is a fixed frequency and a duty cycle of the second switching bridge is fixed at 50:50.
13. The method of claim 12 , wherein the first converter stage comprises a buck PWM converter.
14. The method of claim 12 , wherein the first converter stage comprises a boost PWM converter.
15. The method of claim 12 , wherein the switching stage is a half-bridge switching stage.
16. The method of claim 12 , wherein the switching stage is a full-bridge switching stage.
17. The method of claim 12 , wherein the rectifier comprises two semiconductor switches.
18. The method of claim 12 , wherein the rectifier comprises four semiconductor switches.
19. The method of claim 17 , wherein the semiconductor switches are MOSFETs.
20. The method of claim 12 , further comprising:
providing power from a power supply to the power converter; and
converting the power from the power supply via the power converter into power for one or more loads.