Bidirectional direct current power conversion circuits and methods

• US 6,369,651 B2
• Filed: 03/22/2001
• Issued: 04/09/2002
• Est. Priority Date: 04/02/1998
• Status: Expired due to Term

• Current Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Original Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Inventors: Dent, Paul Wilkinson
• Primary Examiner(s): Pascal, Robert
• Assistant Examiner(s): NGUYEN, KHANH V
• Application Number:
  US09/814,506
• Publication Number:
  US 20010030581A1
• Time in Patent Office: 383 Days
• Field of Search: 330/127, 330/297, 363/21, 363/86, 363/89
• US Class Current: 330/127
• CPC Class Codes: H02M 3/1582 Buck-boost converters H02M3/1584 takes precedence
• CPC Class Codes: H03F 1/0227 using supply converters
• CPC Class Codes: H03F 1/0288 using a main and one or several auxiliary peaking amplifiers whereby the load is connected to the main amplifier using an impedance inverter, e.g. Doherty amplifiers
• CPC Class Codes: H03F 1/0294 using vector summing of two or more constant amplitude phase-modulated signals
• CPC Class Codes: H03F 2200/198 A hybrid coupler being used as coupling circuit between stages of an amplifier circuit
• CPC Class Codes: H03F 2200/324 An amplitude modulator or demodulator being used in the amplifier circuit
• CPC Class Codes: H03F 2200/331 Sigma delta modulation being used in an amplifying circuit
• CPC Class Codes: H03F 2200/336 A I/Q, i.e. phase quadrature, modulator or demodulator being used in an amplifying circuit
• CPC Class Codes: H03F 2200/432 Two or more amplifiers of different type are coupled in parallel at the input or output, e.g. a class D and a linear amplifier, a class B and a class A amplifier
• CPC Class Codes: H03F 2200/504 the supply voltage or current being continuously controlled by a controlling signal, e.g. the controlling signal of a transistor implemented as variable resistor in a supply path for, an IC-block showed amplifier
• CPC Class Codes: H03F 2200/516 Some amplifier stages of an amplifier use supply voltages of different value
• CPC Class Codes: H03F 2200/537 A transformer being used as coupling element between two amplifying stages
• CPC Class Codes: H03F 2200/541 Transformer coupled at the output of an amplifier
• CPC Class Codes: H03F 2200/543 A transmission line being used as coupling element between two amplifying stages
• CPC Class Codes: H03F 2203/21142 Output signals of a plurality of power amplifiers are parallel combined to a common output
• CPC Class Codes: H03F 3/211 using a combination of several amplifiers H03F3/60 takes precedence
• CPC Class Codes: H03F 3/602 Combinations of several amplifiers
• CPC Class Codes: H03G 3/004 Control by varying the supply voltage
• CPC Class Codes: H03G 3/3042 in modulators, frequency-changers, transmitters or power amplifiers transmission power control in bidirectional transmission systems H04W52/04

Abstract

Bidirectional Direct Current (DC) power conversion circuits and methods transfer DC power in a forward direction from a first terminal at a first voltage to a second terminal at a second voltage, wherein the first voltage is higher than the second voltage relative to a common voltage at a common terminal, and in a reverse direction from the second terminal at the second voltage to the first terminal at the first voltage. These bidirectional DC power conversion circuits and methods use an inductor having first and second inductor ends, a first switch that is connected between the first terminal and the first inductor end, to define a node therebetween, and a second switch that is connected between the node and the common terminal, wherein the second inductor end is connected to the second terminal. A switch controller or controlling method is configured to simultaneously close the first switch and open the second switch, to simultaneously open the first switch and close the second switch, and to maintain the first switch closed and the second switch open for a percentage of time that approximates a ratio of the second voltage to the first voltage. Power is thereby transferred from the second terminal to the first terminal when current flows from the first terminal to the second terminal, and power is thereby transferred from the first terminal to the second terminal when current flows from the second terminal to the first terminal.

Claims

1. A bidirectional direct current power conversion circuit comprising:

an inductor having first and second inductor ends;

a first switch connected between a first terminal and the first inductor end, the second inductor end being connected to a second terminal, the inductor and the first switch defining a node therebetween;

a second switch connected between the node and a common terminal; and

a switch controller that is configured to control the first and second switches such that the first switch is closed for a proportion of time approximately equal to a ratio of a lower voltage to a higher voltage and the second switch is opened when the first switch is closed and is closed when the first switch is opened, wherein the circuit transfers power in a forward direction from the first terminal at the higher voltage relative to the common terminal, to the second terminal at the lower voltage relative to the common terminal and in a reverse direction from the second terminal at the lower voltage, to the first terminal at the higher voltage, such that power is transferred from the lower voltage to the higher voltage when current flows from the lower voltage into the second terminal and power is transferred from the higher voltage to the lower voltage when current flows from the higher voltage into the first terminal, and the direction of current flow is defined such that current flows in the same direction as power flows.

2. The power conversion circuit according to claim 1 wherein the first terminal is a DC output terminal of a DC power supply and wherein the second terminal is a power supply input of a power amplifier.

3. A bidirectional Direct Current (DC) power conversion circuit comprising:

an inductor having first and second inductor ends;

a first switch that is connected between a first terminal and the first inductor end to define a node therebetween;

a second switch that is connected between the node and a common terminal;

the second inductor end being connected to a second terminal; and

a switch controller that is configured to simultaneously close the first switch and open the second switch, to simultaneously open the first switch and close the second switch and to maintain the first switch closed and the second switch open for a percentage of time that approximates a ratio of the second voltage to a first voltage, wherein the circuit transfers DC power in a forward direction from the first terminal at the first voltage to the second terminal at the second voltage, wherein the first voltage is higher than the second voltage relative to a common voltage at the common terminal, and in a reverse direction from the second terminal at the second voltage to the first terminal at the first voltage..

4. The power conversion circuit according to claim 3 wherein the switch controller is further configured to simultaneously close the first switch and open the second switch, to simultaneously open the first switch and close the second switch and to maintain the first switch closed and the second switch open for a percentage of time that approximates a ratio of the second voltage to the first voltage such that power is transferred from the second terminal to the first terminal when current flows from the first terminal to the second terminal and power is transferred from the first terminal to the second terminal when current flows from the second terminal to the first terminal.

5. The power conversion circuit according to claim 3 wherein the first terminal is a DC output terminal of a DC power supply and wherein the second terminal is a power supply input of a power amplifier.

6. A bidirectional direct current power conversion method comprising:

providing an inductor having first and second inductor ends, a first switch connected between a first terminal and the first inductor end, the second inductor end being connected to a second terminal, the inductor and the first switch defining a node therebetween, and a second switch connected between the node and a common terminal;

controlling the first and second switches such that the first switch is closed for a proportion of time approximately equal to a ratio of the lower voltage to the higher voltage and the second switch is opened when the first switch is closed and is closed when the first switch is opened, wherein power is transferred in a forward direction from the first terminal at a higher voltage relative to the common terminal, to the second terminal at a lower voltage relative to the common terminal and in a reverse direction from the second terminal at the lower voltage, to the first terminal at the higher voltage, such that power is transferred from the lower voltage to the higher voltage when current flows from the lower voltage into the second terminal and power is transferred from the higher voltage to the lower voltage when current flows from the higher voltage into the first terminal, and the direction of current flow is defined such that current flows in the same direction as power flows.

7. The method according to claim 6 further comprising coupling the first terminal to a DC output terminal of a DC power supply and coupling the second terminal to a power supply input of a power amplifier.

8. A bidirectional Direct Current (DC) power conversion method comprising:

providing an inductor having first and second inductor ends, a first switch that is connected between a first terminal and the first inductor end to define a node therebetween, a second switch that is connected between the node and a common terminal, the second inductor end being connected to a second terminal;

simultaneously closing the first switch and opening the second switch;

simultaneously opening the first switch and closing the second switch; and

maintaining the first switch closed and the second switch open for a percentage of time that approximates a ratio of the second voltage to the first voltage, wherein DC power is transferred in a forward direction from the first terminal at a first voltage to the second terminal at a second voltage, wherein the first voltage is higher than the second voltage relative to a common voltage at the common terminal, and in a reverse direction from the second terminal at the second voltage to the first terminal at the first voltage.

9. The method according to claim 8 wherein the maintaining the first switch closed and the second switch open for a percentage of time that approximates a ratio of the second voltage to the first voltage comprises maintaining the first switch closed and the second switch open for a percentage of time that approximates a ratio of the second voltage to the first voltage such that power is transferred from the second terminal to the first terminal when current flows from the first terminal to the second terminal and power is transferred from the first terminal to the second terminal when current flows from the second terminal to the first terminal.

10. The method according to claim 8 further comprising coupling the first terminal to a DC output terminal of a DC power supply and coupling the second terminal to a power supply input of a power amplifier.