Full range soft-switching DC-DC converter

Claim 1

An apparatus for converting an input DC voltage from an input DC voltage source to a DC output voltage supplied to a load, the apparatus comprising: a divider circuit comprising two capacitors connected in series thereby defining a node therebetween, the divider circuit being coupled in parallel with the input DC voltage source; first and second switching networks, each switching network having an output junction, a first path for carrying load current and arranged between the output it junction and a positive side of the input DC voltage source, a second path for carrying load current and arranged between the output junction and a negative side of the input DC voltage source, the first and second paths each having a blocking state and a conducting state and each having a control input, wherein the respective states of the first and second paths are selected based on a control signal applied to the respective control inputs; a first and second power transformer, each transformer having at least one primary winding and at least one secondary winding, each winding having a polarity, the primary winding of the first transformer connected between the output junction of the first switching network and the node of the divider circuit, the primary winding of the second transformer connected between the output junction of the second switching network and the node of the divider circuit, the secondary windings of the first and second transformers connected in series with each other thereby forming a transformer secondary circuit having two end terminals; a voltage rectifier coupled with the two end terminals of the transformer secondary circuit and providing the output DC voltage; and a controller coupled between the voltage rectifier and the control inputs of the first and second devices of the first switching network and the third and fourth devices of the second switching network, wherein the controller responsively shifts a phase relationship of the first and second switching networks to maintain the output voltage of the output DC voltage source at a selected level, wherein, a relative phase between a current induced on the secondary winding of the first transformer and a current induced on the secondary winding of the second transformer affects the DC output voltage such that the DC output voltage varies with respect to a fixed voltage of the node of the divider circuit when the relative phase is varied.

Claim 2

An apparatus for converting an input DC voltage from an input DC voltage source to a DC output voltage supplied to a load, the apparatus comprising: a divider circuit comprising two capacitors connected in series thereby defining a node therebetween, the divider circuit being coupled in parallel with the input DC voltage source; first and second switching networks, each switching network having an output junction, a first path for carrying load current and arranged between the output it junction and a positive side of the input DC voltage source, a second path for carrying load current and arranged between the output junction and a negative side of the input DC voltage source, the first and second paths each having a blocking state and a conducting state and each having a control input, wherein the respective states of the first and second paths are selected based on a control signal applied to the respective control inputs; a first and second power transformer, each transformer having at least one primary winding and at least one secondary winding, each winding having a polarity, the primary winding of the first transformer connected between the output junction of the first switching network and the node of the divider circuit, the primary winding of the second transformer connected between the output junction of the second switching network and the node of the divider circuit, the secondary windings of the first and second transformers connected in series with each other thereby forming a transformer secondary circuit having two end terminals; a voltage rectifier coupled with the two end terminals of the transformer secondary circuit and providing the output DC voltage; and a controller coupled between the voltage rectifier and the control inputs of the first and second devices of the first switching network and the third and fourth devices of the second switching network, wherein the controller responsively shifts a phase relationship of the first and second switching networks to maintain the output voltage of the output DC voltage source at a selected level, wherein, a relative phase between a current induced on the secondary winding of the first transformer and a current induced on the secondary winding of the second transformer affects the DC output voltage such that the DC output voltage varies with respect to a fixed voltage of the node of the divider circuit when the relative phase is varied.

Claim 4

An apparatus for converting an input DC voltage from an input DC voltage source to a DC output voltage supplied to a load, the apparatus comprising: a divider circuit comprising two capacitors connected in series thereby defining a node therebetween, the divider circuit being coupled in parallel with the input DC voltage source; first and second switching networks, each switching network having an output junction, a first path for carrying load current and arranged between the output junction and a positive side of the input DC voltage source, a second path for carrying load current and arranged between the output junction and a negative side of the input DC voltage source, the first and second paths each having a blocking state and a conducting state and each having a control input, wherein the respective states of the first and second paths are selected based on a control signal applied to the respective control inputs; a first and second power transformer, each transformer having at least one primary winding and at least one secondary winding, each winding having a polarity, the primary winding of the first transformer connected between the output junction of the first switching network and the node of the divider circuit, the primary winding of the second transformer connected between the output junction of the second switching network and the node of the divider circuit, the secondary windings of the first and second transformers connected in series with each other thereby forming a transformer secondary circuit having two end terminals; a voltage rectifier coupled with the two end terminals of the transformer secondary circuit and providing the output DC voltage; a controller coupled between the voltage rectifier and the control inputs of the first and second devices of the first switching network and the third and fourth devices of the second switching network, wherein the controller responsively shifts a phase relationship of the first and second switching networks to maintain the output voltage of the output DC voltage source at a selected level; and a first inductor coupled between the output junction of the first switching network and the node of the divider circuit and a second inductor coupled between the output junction of the second switching network and the node of the divider circuit.

Claim 5

An apparatus for converting an input DC voltage from an input DC voltage source to a DC output voltage supplied to a load, the apparatus comprising: a divider circuit comprising two capacitors connected in series thereby defining a node therebetween, the divider circuit being coupled in parallel with the input DC voltage source; first and second switching networks, each switching network having an output junction, a first path for carrying load current and arranged between the output junction and a positive side of the input DC voltage source, a second path for carrying load current and arranged between the output junction and a negative side of the input DC voltage source, the first and second paths each having a blocking state and a conducting state and each having a control input, wherein the respective states of the first and second paths are selected based on a control signal applied to the respective control inputs; a first and second power transformer, each transformer having at least one primary winding and at least one secondary winding, each winding having a polarity, the primary winding of the first transformer connected between the output junction of the first switching network and the node of the divider circuit, the primary winding of the second transformer connected between the output junction of the second switching network and the node of the divider circuit, the secondary windings of the first and second transformers connected in series with each other thereby forming a transformer secondary circuit having two end terminals; a voltage rectifier coupled with the two end terminals of the transformer secondary circuit and providing the output DC voltage; a controller coupled between the voltage rectifier and the control inputs of the first and second devices of the first switching network and the third and fourth devices of the second switching network, wherein the controller responsively shifts a phase relationship of the first and second switching networks to maintain the output voltage of the output DC voltage source at a selected level; and a first inductor coupled between the output junction of the first switching network and the node of the divider circuit and a second inductor coupled between the output junction of the second switching network and the node of the divider circuit.

Claim 6

An apparatus for converting an input DC voltage from an input DC voltage source having a first terminal and a second terminal, to an output voltage, the apparatus comprising: a) a divider circuit, the divider circuit i) including a first capacitor and a second capacitor coupled in series thereby defining a node therebetween, and ii) coupled across the first and second terminals of the input DC voltage source; b) a first switching network, the first switching network i) coupled across the first and second terminals of the input DC voltage source, ii) having an output node, iii) having a first device having a conducting state for creating a current path between the first terminal of the input voltage source and the output node, and a blocking state, the first device having an input terminal for receiving a first control signal which determines whether the first device is in its conducting state or its blocking state, and iv) having a second device having a conducting state for creating a current path between the second terminal of the input voltage source and the output node and a blocking state, the second device having an input terminal for receiving a second control signal which determines whether the second device is in its conducting state or its blocking state; c) a second switching network, the second switching network i) coupled across the first and second terminals of the input DC voltage source, ii) having an output node, iii) having a third device having a conducting state for creating a current path between the first terminal of the input voltage source and the output node of the second switching network, and a blocking state, the third device of the second switching network having an input terminal for receiving a third control signal which determines whether the third device of the second switching network is in its conducting state or its blocking state, and iv) having a fourth device having a conducting state for creating a current path between the second terminal of the input voltage source and the output node of the second switching network, and a blocking state, the fourth device of the second switching network having an input terminal for receiving a fourth control signal which determines whether the fourth device of the second switching network is in its conducting state or its blocking state; d) a transformer, the transformer i) having a primary winding coupled between the output node of the first switching network and the output node of the second switching network, and ii) having a secondary winding inductively coupled with the primary winding, the secondary winding having a first terminal node and a second terminal node; e) a first inductor coupled between the output node of the first switching network and the node of the divider circuit; and f) a second inductor coupled between the output node of the second switching network and the node of the divider circuit, wherein the output voltage appears across the first and second terminal nodes.

Claim 7

An apparatus for converting an input DC voltage from an input DC voltage source having a first terminal and a second terminal, to an output voltage, the apparatus comprising: a) a divider circuit, the divider circuit i) including a first capacitor and a second capacitor coupled in series thereby defining a node therebetween, and ii) coupled across the first and second terminals of the input DC voltage source; b) a first switching network, the first switching network i) coupled across the first and second terminals of the input DC voltage source, ii) having an output node, iii) having a first device having a conducting state for creating a current path between the first terminal of the input voltage source and the output node, and a blocking state, the first device having an input terminal for receiving a first control signal which determines whether the first device is in its conducting state or its blocking state, and iv) having a second device having a conducting state for creating a current path between the second terminal of the input voltage source and the output node and a blocking state, the second device having an input terminal for receiving a second control signal which determines whether the second device is in its conducting state or its blocking state; c) a second switching network, the second switching network i) coupled across the first and second terminals of the input DC voltage source, ii) having an output node, iii) having a third device having a conducting state for creating a current path between the first terminal of the input voltage source and the output node of the second switching network, and a blocking state, the third device of the second switching network having an input terminal for receiving a third control signal which determines whether the third device of the second switching network is in its conducting state or its blocking state, and iv) having a fourth device having a conducting state for creating a current path between the second terminal of the input voltage source and the output node of the second switching network, and a blocking state, the fourth device of the second switching network having an input terminal for receiving a fourth control signal which determines whether the fourth device of the second switching network is in its conducting state or its blocking state; d) a transformer, the transformer i) having a primary winding coupled between the output node of the first switching network and the output node of the second switching network, and ii) having a secondary winding inductively coupled with the primary winding, the secondary winding having a first terminal node and a second terminal node; e) a first inductor coupled between the output node of the first switching network and the node of the divider circuit; and f) a second inductor coupled between the output node of the second switching network and the node of the divider circuit, wherein the output voltage appears across the first and second terminal nodes.

Claim 9

An apparatus for converting an input DC voltage from an input DC voltage source having a first terminal and a second terminal, to an output voltage, the apparatus comprising: a) a divider circuit, the divider circuit i) including a first capacitor and a second capacitor coupled in series thereby defining a node therebetween, and ii) coupled across the first and second terminals of the input DC voltage source; b) a first switching network, the first switching network i) coupled across the first and second terminals of the input DC voltage source, ii) having an output node, iii) having a first device having a conducting state for creating a current path between the first terminal of the input voltage source and the output node, and a blocking state, the first device having an input terminal for receiving a first control signal which determines whether the first device is in its conducting state or its blocking state, and iv) having a second device having a conducting state for creating a current path between the second terminal of the input voltage source and the output node and a blocking state, the second device having an input terminal for receiving a second control signal which determines whether the second device is in its conducting state or its blocking state; c) a second switching network, the second switching network i ) coupled across the first and second terminals of the input DC voltage source, ii) having an output node, iii) having a third device having a conducting state for creating a current path between the first terminal of the input voltage source and the output node of the second switching network, and a blocking state, the third device of the second switching network having an input terminal for receiving a third control signal which determines whether the third device of the second switching network is in its conducting state or its blocking state, and iv) having a fourth device having a conducting state for creating a current path between the second terminal of the input voltage source and the output node of the source switching network, and a blocking state, the fourth device of the second switching network having an input terminal for receiving a fourth control signal which determines whether the fourth device of the second switching network is in its conducting state or its blocking state; d) a first transformer, the first transformer i) having a primary winding coupled between the output node of the first switching network and the node of the divider circuit, and ii) having a secondary winding inductively coupled with the primary winding; e) a second transformer, the second transformer i) having a primary winding coupled between the output node of the second switching network and the node of the divider circuit, and ii) having a secondary winding inductively coupled with the primary winding of the second transformer, the secondary winding of the second transformer connected in series with the secondary winding of the first transformer thereby forming a series connection of secondary windings having a first terminal node and a second terminal node, wherein the output voltage appears across the first and second terminal nodes; and f) a first inductor coupled between the output node of the first switching network and the node of the divider circuit and a second inductor coupled between the output node of the second switching network and the node of the divider circuit.

Claim 10

An apparatus for converting an input DC voltage from an input DC voltage source having a first terminal and a second terminal, to an output voltage, the apparatus comprising: a) a divider circuit, the divider circuit i) including a first capacitor and a second capacitor coupled in series thereby defining a node therebetween, and ii) coupled across the first and second terminals of the input DC voltage source; b) a first switching network, the first switching network i) coupled across the first and second terminals of the input DC voltage source, ii) having an output node, iii) having a first device having a conducting state for creating a current path between the first terminal of the input voltage source and the output node, and a blocking state, the first device having an input terminal for receiving a first control signal which determines whether the first device is in its conducting state or its blocking state, and iv) having a second device having a conducting state for creating a current path between the second terminal of the input voltage source and the output node and a blocking state, the second device having an input terminal for receiving a second control signal which determines whether the second device is in its conducting state or its blocking state; c) a second switching network, the second switching network i ) coupled across the first and second terminals of the input DC voltage source, ii) having an output node, iii) having a third device having a conducting state for creating a current path between the first terminal of the input voltage source and the output node of the second switching network, and a blocking state, the third device of the second switching network having an input terminal for receiving a third control signal which determines whether the third device of the second switching network is in its conducting state or its blocking state, and iv) having a fourth device having a conducting state for creating a current path between the second terminal of the input voltage source and the output node of the source switching network, and a blocking state, the fourth device of the second switching network having an input terminal for receiving a fourth control signal which determines whether the fourth device of the second switching network is in its conducting state or its blocking state; d) a first transformer, the first transformer i) having a primary winding coupled between the output node of the first switching network and the node of the divider circuit, and ii) having a secondary winding inductively coupled with the primary winding; e) a second transformer, the second transformer i) having a primary winding coupled between the output node of the second switching network and the node of the divider circuit, and ii) having a secondary winding inductively coupled with the primary winding of the second transformer, the secondary winding of the second transformer connected in series with the secondary winding of the first transformer thereby forming a series connection of secondary windings having a first terminal node and a second terminal node, wherein the output voltage appears across the first and second terminal nodes; and f) a first inductor coupled between the output node of the first switching network and the node of the divider circuit and a second inductor coupled between the output node of the second switching network and the node of the divider circuit.

Claim 11

An apparatus for converting an input DC voltage from an input DC, voltage source having a first terminal and a second terminal, to an output voltage, the apparatus comprising: a) a divider circuit, the divider circuit i) including a first capacitor and a second capacitor coupled in series thereby defining a node therebetween, and ii) coupled across the first and second terminals of the input DC voltage source; b) a first switching network, the first switching network i) coupled across the first and second terminals of the input DC voltage source, ii) having an output node, iii) having a first device having a conducting state for creating a current path between the is first terminal of the input voltage source and the output node, and a blocking state, the first device having an input terminal for receiving a first control signal which determines whether the first device is in its conducting state or its blocking state, and iv) having a second device having a conducting state for creating a current path between the second terminal of the input voltage source and the output node and a blocking state, the second device having an input terminal for receiving a second control signal which determines whether the second device is in its conducting state or its blocking state; c) a second switching network, the second switching network i) coupled across the first and second terminals of the input DC voltage source, ii) having an output node, iii) having a third device having a conducting state for creating a current path between the first terminal of the input voltage source and the output node of the second switching network, and a blocking state, the third device of the second switching network having an input terminal for receiving a third control signal which determines whether the third device of the second switching network is in its conducting state or its blocking state, and iv) having a fourth device having a conducting state for creating a current path between the second terminal of the input voltage source and the output node of the second switching network, and a blocking state, the fourth device of the second switching network having an input terminal for receiving a fourth control signal which determines whether the fourth device of the second switching network is in its conducting state or its blocking state; d) a first transformer, the first transformer i) having a primary winding coupled between the output node of the first switching network and the node of the divider circuit, and ii) having a secondary winding inductively coupled with the primary winding; e) a second transformer, the second transformer i) having a primary winding coupled between the output node of the second switching network and the node of the divider circuit, and ii) having a secondary winding inductively coupled with the primary winding of the second transformer, the secondary winding of the second transformer connected in series with the secondary winding of the first transformer thereby forming a series connection of secondary windings having a first terminal node and a second terminal node, wherein the output voltage appears across the first and second terminal nodes, and wherein a relative phase between a current induced on the secondary winding of the first transformer and a current induced on the secondary winding of the second transformer affects the output voltage appearing across the first and second terminal nodes such that the output voltage varies with respect to a fixed voltage of the node of the divider circuit when the relative phase is varied.

Claim 12

An apparatus for converting an input DC voltage from an input DC, voltage source having a first terminal and a second terminal, to an output voltage, the apparatus comprising: a) a divider circuit, the divider circuit i) including a first capacitor and a second capacitor coupled in series thereby defining a node therebetween, and ii) coupled across the first and second terminals of the input DC voltage source; b) a first switching network, the first switching network i) coupled across the first and second terminals of the input DC voltage source, ii) having an output node, iii) having a first device having a conducting state for creating a current path between the is first terminal of the input voltage source and the output node, and a blocking state, the first device having an input terminal for receiving a first control signal which determines whether the first device is in its conducting state or its blocking state, and iv) having a second device having a conducting state for creating a current path between the second terminal of the input voltage source and the output node and a blocking state, the second device having an input terminal for receiving a second control signal which determines whether the second device is in its conducting state or its blocking state; c) a second switching network, the second switching network i) coupled across the first and second terminals of the input DC voltage source, ii) having an output node, iii) having a third device having a conducting state for creating a current path between the first terminal of the input voltage source and the output node of the second switching network, and a blocking state, the third device of the second switching network having an input terminal for receiving a third control signal which determines whether the third device of the second switching network is in its conducting state or its blocking state, and iv) having a fourth device having a conducting state for creating a current path between the second terminal of the input voltage source and the output node of the second switching network, and a blocking state, the fourth device of the second switching network having an input terminal for receiving a fourth control signal which determines whether the fourth device of the second switching network is in its conducting state or its blocking state; d) a first transformer, the first transformer i) having a primary winding coupled between the output node of the first switching network and the node of the divider circuit, and ii) having a secondary winding inductively coupled with the primary winding; e) a second transformer, the second transformer i) having a primary winding coupled between the output node of the second switching network and the node of the divider circuit, and ii) having a secondary winding inductively coupled with the primary winding of the second transformer, the secondary winding of the second transformer connected in series with the secondary winding of the first transformer thereby forming a series connection of secondary windings having a first terminal node and a second terminal node, wherein the output voltage appears across the first and second terminal nodes, and wherein a relative phase between a current induced on the secondary winding of the first transformer and a current induced on the secondary winding of the second transformer affects the output voltage appearing across the first and second terminal nodes such that the output voltage varies with respect to a fixed voltage of the node of the divider circuit when the relative phase is varied.