DC-DC CONVERTER FOR ELECTRIC POWER USING A DC ELECTRIC POWER SOURCE

• US 20120307527A1
• Filed: 11/24/2010
• Published: 12/06/2012
• Est. Priority Date: 11/26/2009
• Status: Active Grant

• Current Assignee: Centre National D'Etudes Spatiales
• Original Assignee: Centre National D'Etudes Spatiales
• Inventors: Schwander, Denis
• Granted Patent: US 9,106,145 B2
• Time in Patent Office: Days
• US Class Current: 363/16
• CPC Class Codes: H02M 3/01 Resonant DC/DC converters
• CPC Class Codes: H02M 3/33553 with galvanic isolation between input and output of both the power stage and the feedback loop
• CPC Class Codes: H02M 3/33573 Full-bridge at primary side of an isolation transformer

Abstract

The converter comprises an inverter and a conversion unit in which a transformer powers a controlled rectifier formed by saturable inductors and power diodes. According to the invention, a series reactive circuit associated with the transformer co-operates with the controlled rectifier for the phase displacement of the voltage applied at the primary of the transformer in relation to the current flowing therethrough. The phase displacement is regulated by a control voltage as a function of the variations in the output voltage of the converter.

Claims

1. A DC-DC converter intended to convert the electricity provided by an energy source delivering a first direct voltage and a first direct current having first respective values into output electricity at a second direct voltage and a second direct current having second respective values, said converter including:

an inverter powered by said energy source and intended to create alternative energy at a third voltage and with a third current,

a conversion unit intended to deliver said output energy, and

a regulator associated with said conversion unit to regulate said second voltage,

said conversion unit having a transducer powered by said inverter and feeding into a controlled rectifier intended to provide said second voltage,

said controlled rectifier including two serial circuits with opposite conduction directions each made up of a power diode and a saturable induction coil, said saturable induction coils magnetically controlling, during each cycle of the third voltage delivered by said inverter, the beginning- and end-of-conduction moments of said power diodes, and

said regulator being connected to analyze said second voltage

of said output energy and, as a function of that analysis, to create a control voltage intended to regulate said second voltage, and

said controlled rectifier also including two regulating diodes connected to inject said control voltage respectively into the connection nodes between the power diode and the saturable induction coil of said serial circuits of said controlled rectifier,

said converter being wherein it also includes a reactive serial circuit associated with said transducer and cooperating with said controlled rectifier to phase-shift said third voltage relative to said third current, and in that said control voltage regulates the phase shift between them as a function of the alternatives of said second voltage.

2. The DC-DC converter according to claim 1, wherein said reactive serial circuit comprises an inductance mounted between said inverter and said transducer.

3. The DC-DC converter according to claim 1, wherein said reactive circuit is realized in said transducer, which to that end has a significant leakage inductance between its primary and its secondary, weakly coupled to one another.

4. The DC-DC converter according to claim 1, wherein said reactive serial circuit comprises an inductance and a capacitance mounted in series between said inverter and said transducer.

5. The DC-DC converter according to claim 2, wherein at least part of said reactive serial circuit is formed by the cabling connecting said inverter to said transducer.

6. The DC-DC converter according to claim 1, wherein said transducer includes a secondary made from two half-windings strongly coupled to one another and each powering one of the serial circuits of a power diode and a saturable induction coil, and in that said second voltage is taken between the middle point between the half-windings of said secondary and the node between said power diodes.

7. The DC-DC converter according to claim 1, wherein said controlled rectifier is mounted as a voltage doubler.

8. The DC-DC converter according to claim 7, wherein said transducer has a secondary whereof one of the terminal is connected to said serial circuits of a power diode and a saturable induction coil, and whereof the other terminal is connected to each of said diodes by means of a capacitor.

9. The DC-DC converter according to claim 7, wherein said reactive serial circuit comprises an inductance mounted between the secondary of the transformer and said voltage doubler.

10. The DC-DC converter according to claim 7, wherein said reactive circuit comprises an inductance and a capacitance mounted in series between the secondary of said transducer and said voltage doubler.

11. The DC-DC converter according to claim 3, wherein said reactive circuit is realized in said transducer owing to a distribution by construction between the primary and the secondary thereof, a resonance capacitance being possibly be placed in series on the primary side and/or secondary side, and wherein said controlled rectifier is mounted as a voltage doubler.

12. An electricity distribution facility, in particular for satellites, wherein it includes a DC-DC converter according claim 1, built with a plurality of conversion units each connected to said inverter by means of an individual cabling, and in that each of said conversion units comprises its own voltage regulator.

13. An electricity distribution facility, in particular for satellites, wherein it includes a DC-DC converter according to claim 1, built with a plurality of conversion units, said conversion units being distributed in groups of at least three units whereof the outputs are placed in parallel, and in that the conversion units of each of said groups are connected to said inverter by a multi-line cable.

14. The electricity distribution facility according to claim 13, wherein in each of said groups of conversion units said conversion units are connected in a triangle or in a star.

15. The electricity distribution facility according to claim 13, wherein in each of said groups of conversion units, said conversion units are regulated by a shared single regulator.

16. An electricity distribution facility, in particular for a satellite, wherein it includes a converter according to claim 9, built with a plurality of conversion units powered by a shared transducer including a plurality of secondaries at a rate of one per unit.

17. The distribution facility according to claim 16, wherein each of said conversion units is provided with its own regulator.

18. An electricity distribution facility, in particular for a satellite, wherein it includes a converter according to claim 9, built with a plurality of conversion units arranged in at least one group of conversion units powered by means of a shared transducer connected by its primary to said inverter and including as many secondaries as there are conversion units in a group,

in that one of said conversion units of a group being a pilot conversion unit formed by a symmetrical rectifier with no phase shift means,

in that said inverter is adjustable,

in that the facility includes an adjustment loop acting on said inverter to adjust it as a function of the difference signal between a voltage reference signal and a signal depending on the output voltage of said pilot conversion unit, and

in that the other conversion units of a group being provided with their own regulator.