Forward boost power converters with tapped transformers and related methods
In a switching mode power converter coupled between first and second terminal pairs, a first circuit path includes a first inductance and a first switch. A tapped transformer has a first winding coupled across the first inductance and a tapped second winding with a tapped winding portion. A second circuit path includes a capacitance coupled to a second inductance, and the second circuit path is coupled to the first inductance through the tapped winding portion in a third circuit path and through the second winding in a fourth circuit path. During their respective conduction periods, the first switch couples the first inductance across the first terminal pair, a second switch completes a circuit between the second terminal pair and the second circuit path or the third circuit path, and a third switch completes a circuit that includes another of the second circuit path and the fourth circuit path.
1. A switching mode power converter coupled between a first terminal pair and a second terminal pair, the converter comprising:
a first inductance coupled to a first switch in a first circuit path across said first terminal pair, said first switch coupling said first inductance across said first terminal pair during a conduction period of said first switch;
a tapped transformer having a first winding coupled across said first inductance and a second winding, said second winding having a tapped winding portion;
a capacitance coupled to a second inductance in a second circuit path, said second circuit path being coupled to said first inductance through said tapped winding portion in a third circuit path and coupled to said first inductance through said second winding in a fourth circuit path;
a second switch and a third switch, said second switch operated to be in a non-conducting state when said third switch is in a conducting state and said third switch operated to be in a non-conducting state when said second switch is in a conducting state,
said second switch completing a circuit between said second terminal pair and one of: said second circuit path and said third circuit path through said tapped winding portion during a conduction period of said second switch,
said third switch completing a circuit comprising another of: said second circuit path and said fourth circuit path through said second winding during a conduction period of said third switch.
2. The switching mode power converter of claim 1 , wherein said first terminal pair and said second terminal pair share a common terminal.
3. The switching mode power converter of claim 1 , said first terminal pair comprising an input terminal pair, said second terminal pair comprising an output terminal pair, said capacitance transferring energy to said output terminal pair during said conduction period of said second switch.
4. The switching mode power converter of claim 3 , said first inductance being coupled to said capacitance and transferring energy to said output terminal pair during said conduction period of said second switch.
5. The switching mode power converter of claim 3 , said first inductance being coupled to said capacitance and transferring energy to said capacitance during said conduction period of said third switch.
6. The switching mode power converter of claim 1 , said first terminal pair comprising an output terminal pair, said second terminal pair comprising an input terminal pair, said first inductance transferring energy to said output terminal pair during said conduction period of said first switch.
7. The switching mode power converter of claim 6 , said first inductance being coupled to said capacitance and storing energy from said input terminal pair during said conduction period of said second switch.
8. The switching mode power converter of claim 7 , said first inductance and said capacitance transferring energy to said output terminal pair during said conduction period of said first switch.
9. The switching mode power converter of claim 7 , said capacitance transferring energy to said output terminal pair during said conduction period of said third switch.
10. The switching mode power converter of claim 1 , said first inductance comprising magnetisation inductance of said tapped transformer.
11. The switching mode power converter of claim 1 , said second inductance comprising leakage inductance of said tapped transformer.
12. A method of operation of a switching mode power converter coupled between a first terminal pair and a second terminal pair, the converter comprising: a first inductance coupled to a first switch in a first circuit path across said first terminal pair; a tapped transformer having a first winding coupled across said first inductance and a second winding, said second winding having a tapped winding portion; a capacitance coupled to a second inductance in a second circuit path, said second circuit path being coupled to said first inductance through said tapped winding portion in a third circuit path and coupled to said first inductance through said second winding in a fourth circuit path; a second switch and a third switch, said second switch operated to be in a non-conducting state when said third switch is in a conducting state and said third switch operated to be in a non-conducting state when said second switch is in a conducting state, said method comprising:
closing of said first switch to couple said first inductance across said first terminal pair during a conduction period of said first switch;
closing of said second switch to complete a circuit between said second terminal pair and one of said second circuit path and said third circuit path through said tapped winding portion during a conduction period of said second switch so as to transfer energy into said second terminal pair;
closing of said third switch to complete a circuit comprising another of: said second circuit path and said fourth circuit path through said second winding during a conduction period of said third switch so as to transfer energy into said capacitance.
13. Apparatus comprising:
a switching mode power converter coupled between a first terminal pair and a second terminal pair, the converter comprising: a first inductance coupled to a first switch in a first circuit path across said first terminal pair; a tapped transformer having a first winding coupled across said first inductance and a second winding, said second winding having a tapped winding portion; a capacitance coupled to a second inductance in a second circuit path, said second circuit path being coupled to said first inductance through said tapped winding portion in a third circuit path and coupled to said first inductance through said second winding in a fourth circuit path; a second switch and a third switch; said second switch operated to be in a non-conducting state when said third switch is in a conducting state and said third switch operated to be in a non-conducting state when said second switch is in a conducting state,
means for closing said first switch to couple said first inductance across said first terminal pair during a conduction period of said first switch;
means for closing said second switch to complete a circuit between said second terminal pair and one of: said second circuit path and said third circuit path through said tapped winding portion during a conduction period of said second switch so as to transfer energy into said second terminal pair; and
means for closing said third switch to complete a circuit comprising another of: said second circuit path and said fourth circuit path through said second winding during a conduction period of said third switch so as to transfer energy into said capacitance.
14. A switching mode power converter coupled between a first terminal pair and a second terminal pair, the converter comprising:
a first inductance coupled to a first switch in a first circuit path across said first terminal pair, said first switch coupling said first inductance across said first terminal pair during a conduction period of said first switch;
a capacitance coupled to a second inductance in a second circuit path;
a tapped transformer having a first winding coupled across said first inductance and a second winding coupled to said second circuit path, said second winding having a tapped winding portion;
a second switch and a third switch, said second switch operated to be in a non-conducting state when said third switch is in a conducting state and said third switch operated to be in a non-conducting state when said second switch is in a conducting state,
said second switch completing a circuit between said second terminal pair and said second circuit path through said tapped winding portion during a conduction period of said second switch,
said third switch completing a circuit comprising said second circuit path and said second winding during a conduction period of said third switch.
15. The switching mode power converter of claim 14 , said second circuit path being further coupled to said first inductance through said second winding during said conduction period of said third switch.
16. The switching mode power converter of claim 14 , said second circuit path being further coupled to said first inductance through said tapped winding portion during said conduction period of said second switch.
17. The switching mode power converter of claim 16 , said second circuit path being further coupled to said first inductance through said second winding during said conduction period of said third switch.
18. The switching mode power converter of claim 14 , wherein said first terminal pair and said second terminal pair share a common terminal.
19. The switching mode power converter of claim 14 , said first inductance comprising magnetisation inductance of said tapped transformer.
20. The switching mode power converter of claim 14 , said second inductance comprising leakage inductance of said tapped transformer.