Source volt-ampere/load volt-ampere differential converter

• US 4,734,839 A
• Filed: 03/23/1987
• Issued: 03/29/1988
• Est. Priority Date: 03/23/1987
• Status: Expired due to Fees

• Current Assignee: Fred O. Barthold
• Original Assignee: Fred O. Barthold
• Inventors: Barthold, Fred O.
• Primary Examiner(s): Wong, Peter S.
• Application Number:
  US07/028,900
• Time in Patent Office: 372 Days
• Field of Search: 363/16, 363/20, 363/21, 363/97, 363/124, 323/268, 323/271, 323/272, 323/224, 323/222
• US Class Current: 363/16
• CPC Class Codes: H02M 3/33507 with automatic control of the output voltage or current, e.g. flyback converters H02M3/33561, H02M3/33569 take precedence
• CPC Class Codes: H02M 3/33546 with automatic control of the output voltage or current H02M3/33561 takes precedence

Abstract

A source V-A/load V-A differential converter (single quaddrant DC-DC topology) combines the canonical functions of both the boost and buck converter topologies. Basic advantages of the boost and buck topologies are retained, disadvantages of these and prior art compound topologies are eliminated, and several entirely new and useful functions are realized. These new functions include sub-microsecond source voltage/load step response (independent of feedback loop parameters), extremely wide source voltage range, very high conversion efficiency/power density, multiple auxiliary outputs with closely held voltage range parameters (without resort to minimum load, pre-load, or sub-regulation), galvanic input/output isolation, enhanced capacitance safety/energy storage, reduced gain bandwidth requirements, and intrinsic stability. The differential term derives from the transfer function for this new compound topology, i.e., x=δ(a+x).

Claims

1. A source volt-ampere/load volt-ampere differential converter circuit of single quadrant compound switching DC-DC topology comprising:

a DC voltage source;

a first power transformer including a primary winding and a secondary winding, said first power transformer being configured and polarized in the isolated boost mode (fly-back);

a second power transformer including a primary winding and a secondary winding, said second power transformer being configured and polarized in the isolated buck mode (forward);

a first switching device to selectively couple said voltage source across the primary winding of said first power transformer;

a second switching device to selectively couple the boost voltage product of said first power transformer/said first switching device across the primary winding of said second power transformer;

a first unidirectional conducting device connected in series between said first switching device and the primary winding of said first power transformer and oriented to conduct during conduction by said first switching device;

a second unidirectional conducting device connected in series between the junction of said first unidirectional conducting device/primary winding of said first power transformer and a first capacitor, and oriented to conduct during non-conduction by said first switching device;

said first capacitor connected between the series combination of said second unidirectional conducting device/primary winding of said first power transformer and said DC voltage source negative, and oriented to integrate the boost voltage product of said first switching device and said first power transformer;

a third unidirectional conducting device connected in series with the secondary windings of said first and second power transformers, and oriented to conduct during conduction by said second switching device;

a fourth unidirectional conducting device connected in parallel with the series combination of said third unidirectional conducting device/secondary winding of said second power transformer, and oriented to conduct during nonconduction by said first switching device;

a second capacitor connected in parallel with the series combination of said third unidirectional conducting device/secondary windings of said first and second power transformers, and oriented to integrate the compound boost-buck voltage product of said first and second power transformers/said first and second switching devices/said first, second, third, and fourth unidirectional conducting devices/said first capacitor;

a utilization load connected across said second capacitor;

a control means for selectively and simultaneously opening and closing said first and second switching devices for compound energy transfer from said DC voltage source to said utilization load, and responsive to the differential transfer function δ

=t on/(t on+t off)/{1-[t on/(t on+t off)]}.

2. The converter circuit of claim 1 wherein said first and second switching devices are combined into a single switching device.

3. The converter circuit of claim 1 wherein said first and second power transformers are combined into a single integrated core structure.

4. The converter circuit of claim 2 wherein said first and second power transformers are combined into a single integrated core structure.

5. The converter circuit of claim 1 wherein the proliferation of secondary windings of said first and second power transformers, said third and fourth unidirectional conducting devices, and said second capacitor, (all according to the term n+1) provides for proliferation of said utilization load (according to the term n+1).

6. The converter circuit of claim 2 wherein the proliferation of secondary windings of said first and second power transformers, said third and fourth unidirectional conducting devices, and said second capacitor, (all according to the term n+1) provides for proliferation of said utilization load (according to the term n+1).

7. The converter circuit of claim 3 wherein the proliferation of secondary windings of said integrated core structure, said third and fourth unidirectional conducting devices, and said second capacitor, (all according to the term n+1) provides for proliferation of said utilization load (according to the term n+1).

8. The converter circuit of claim 4 wherein the proliferation of secondary windings of said integrated core structure, said third and fourth unidirectional conducting devices, and said second capacitor, (all according to the term n+1) provides for proliferation of said utilization load (according to the term n+1).

9. The converter circuit of claim 1 wherein anti-parallel fifth and sixth unidirectional conducting devices are connected between the junction of serially divided said first capacitor/said boost voltage product and said DC voltage source positive, and oriented to asymptotically conduct during positive or negative voltage excursions between said DC voltage source and said boost voltage product as serially divided by said first capacitor.

10. The converter circuit of claim 2 wherein anti-parallel fifth and sixth unidirectional conducting devices are connected between the junction of serially divided said first capacitor/said boost voltage product and said DC voltage source positive, and oriented to asymptotically conduct during positive or negative voltage excursions between said DC voltage source and said boost voltage product as serially divided by said first capacitor.

11. The converter circuit of claim 3 wherein anti-parallel fifth and sixth unidirectional conducting devices are connected between the junction of serially divided said first capacitor/said boost voltage product and said DC voltage source positive, and oriented to asymptotically conduct during positive or negative voltage excursions between said DC voltage source and said boost voltage product as serially divided by said first capacitor.

12. The converter circuit of claim 4 wherein anti-parallel fifth and sixth unidirectional conducting devices are connected between the junction of serially divided said first capacitor/said boost voltage product and said DC voltage source positive, and oriented to asymptotically conduct during positive or negative voltage excursions between said DC voltage source and said boost voltage product as serially divided by said first capacitor.

13. The converter circuit of claim 5 wherein anti-parallel fifth and sixth unidirectional conducting devices are connected between the junction of serially divided said first capacitor/said boost voltage product and said DC voltage source positive, and oriented to asymptotically conduct during positive or negative voltage excursions between said DC voltage source and said boost voltage product as serially divided by said first capacitor.

14. The converter circuit of claim 6 wherein anti-parallel fifth and sixth unidirectional conducting devices are connected between the junction of serially divided said first capacitor/said boost voltage product and said DC voltage source positive, and oriented to asymptotically conduct during positive or negative voltage excursions between said DC voltage source and said boost voltage product as serially divided by said first capacitor.

15. The converter circuit of claim 7 wherein anti-parallel fifth and sixth unidirectional conducting devices are connected between the junction of serially divided said first capacitor/said boost voltage product and said DC voltage source positive, and oriented to asymptotically conduct during positive or negative voltage excursions between said DC voltage source and said boost voltage product as serially divided by said first capacitor.

16. The converter circuit of claim 8 wherein anti-parallel fifth and sixth unidirectional conducting devices are connected between the junction of serially divided said first capacitor/said boost voltage product and said DC voltage source positive, and oriented to asymptotically conduct during positive or negative voltage excursions between said DC voltage source and said boost voltage product as serially divided by said first capacitor.

17. The converter circuit of claim 1 wherein a first inductor is connected in series with said fourth unidirectional conducting device, and oriented to integrate the isolated boost mode current component of the compound boost-buck current product of said first and second power transformers/said first and second switching devices/said first, second, third, and fourth unidirectional conducting devices/said first and second capacitors.

18. The converter circuit of claim 2 wherein a first inductor is connected in series with said fourth unidirectional conducting device, and oriented to integrate the isolated boost mode current component of the compound boost-buck current product of said first and second power transformers/said combined single switching device/said first, second, third, and fourth unidirectional conducting devices/said first and second capacitors.

19. The converter circuit of claim 3 wherein a first inductor is connected in series with said fourth unidirectional conducting device, and oriented to integrate the isolated boost mode current component of the compound boost-buck current product of said integrated core structure/said first and second switching devices/said first, second, third, and fourth unidirectional conducting devices/said first and second capacitors.

20. The converter circuit of claim 4 wherein a first inductor is connected in series with said fourth unidirectional conducting device, and oriented to integrate the isolated boost mode current component of the compound boost-buck current product of said integrated core structure/said combined single switching device/said first, second, third, and fourth unidirectional conducting devices/said first and second capacitors.

21. The converter circuit of claim 5 wherein a first inductor is connected in series with said fourth unidirectional conducting device, and oriented to integrate the isolated boost mode current component of the compound boost-buck current product of said first and second power transformers/said first and second switching devices/said first, second, third, and fourth unidirectional conducting devices/said first and second capacitors.

22. The converter circuit of claim 6 wherein a first inductor is connected in series with said fourth unidirectional conducting device, and oriented to integrate the isolated boost mode current component of the compound boost-buck current product of said first and second power transformers/said combined single switching device/said first, second, third, and fourth unidirectional conducting devices/said first and second capacitors.

23. The converter circuit of claim 7 wherein a first inductor is connected in series with said fourth unidirectional conducting device, and oriented to integrate the isolated boost mode current component of the compound boost-buck current product of said integrated core structure/said first and second switching devices/said first, second, third, and fourth unidirectional conducting devices/said first and second capacitors.

24. The converter circuit of claim 8 wherein a first inductor is connected in series with said fourth unidirectional conducting device, and oriented to integrate the isolated boost mode current component of the compound boost-buck current product of said integrated core structure/said combined single switching device/said first, second, third, and fourth unidirectional conducting devices/said first and second capacitors.

25. The converter circuit of claim 9 wherein a first inductor is connected in series with said fourth unidirectional conducting device, and oriented to integrate the isolated boost mode current component of the compound boost-buck current product of said first and second power transformers/said first and second switching devices/said first, second, third, fourth, fifth, and sixth unidirectional conducting devices/said first and second capacitors.

26. The converter circuit of claim 10 wherein a first inductor is connected in series with said fourth unidirectional conducting device, and oriented to integrate the isolated boost mode current component of the compound boost-buck current product of said first and second power transformers/said combined single switching device/said first, second, third, fourth, fifth, and sixth unidirectional conducting devices/said first and second capacitors.

27. The converter circuit of claim 11 wherein a first inductor is connected in series with said fourth unidirectional conducting device, and oriented to integrate the isolated boost mode current component of the compound boost-buck current product of said integrated core structure/said first and second switching devices/said first, second, third, fourth, fifth, and sixth unidirectional conducting devices/said first and second capacitors.

28. The converter circuit of claim 12 wherein a first inductor is connected in series with said fourth unidirectional conducting device, and oriented to integrate the isolated boost mode current component of the compound boost-buck current product of said integrated core structure/said combined single switching device/said first, second, third, fourth, fifth, and sixth unidirectional conducting devices/said first and second capacitors.

29. The converter circuit of claim 13 wherein a first inductor is connected in series with said fourth unidirectional conducting device, and oriented to integrate the isolated boost mode current component of the compound boost-buck current product of said first and second power transformers/said first and second switching devices/said first, second, third, fourth, fifth, and sixth unidirectional conducting devices/said first and second capacitors.

30. The converter circuit of claim 14 wherein a first inductor is connected in series with said fourth unidirectional conducting device, and oriented to integrate the isolated boost mode current component of the compound boost-buck current product of said first and second power transformers/said combined single switching device/said first, second, third, fourth, fifth, and sixth unidirectional conducting devices/said first and second capacitors.

31. The converter circuit of claim 15 wherein a first inductor is connected in series with said fourth unidirectional conducting device, and oriented to integrate the isolated boost mode current component of the compound boost-buck current product of said integrated core structure/said first and second switching devices/said first, second, third, fourth, fifth, and sixth unidirectional conducting devices/said first and second capacitors.

32. The converter circuit of claim 16 wherein a first inductor is connected in series with said fourth unidirectional conducting device, and oriented to integrate the isolated boost mode current component of the compound boost-buck current product of said integrated core structure/said combined single switching device/said first, second, third, fourth, fifth, and sixth unidirectional conducting devices/said first and second capacitors.