METHOD OF DRIVING DC/DC CONVERTER, METHOD OF CONTROLLING DC/DC CONVERTER APPARATUS, METHOD OF CONTROLLING DRIVING OPERATION OF VEHICLE, AND METHOD OF DRIVING FUEL CELL SYSTEM

• US 20090166114A1
• Filed: 12/23/2008
• Published: 07/02/2009
• Est. Priority Date: 12/28/2007
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: TAGUCHI, Satoshi, KOJIMA, Yasushi, SAEKI, Hibiki
• Granted Patent: US 8,143,835 B2
• Time in Patent Office: Days
• US Class Current: 180/65.265
• CPC Class Codes: H02M 3/156 with automatic control of output voltage or current, e.g. switching regulators

Abstract

Under the same target voltage, a basic duty ratio depending on a target ON time is set, and prior and subsequent duty ratios before and after upper arm switching devices or lower arm switching devices are driven with the basic duty ratio are set as a basic duty ratio+α and a basic duty ratio−α, respectively. Gate drive signals, having the basic duty ratio and the prior and subsequent duty ratios, are supplied to the upper arm switching devices or to the lower arm switching devices, in order to turn on the upper arm switching devices or the lower arm switching devices.

Claims

1. A method of driving a chopper-type DC/DC converter including at least one reactor and at least one switching device, comprising the steps of:

setting a target duty ratio;

setting a first duty ratio and a second duty ratio based on the target duty ratio; and

driving said switching device for ON times corresponding respectively to the target duty ratio, the first duty ratio and the second duty ratio, wherein

one of the duty ratios is the maximum duty ratio and another one of the duty ratios is the minimum duty ratio, and

the remaining one of the duty ratios is a ratio between the maximum duty ratio and the minimum duty ratio.

3. A method according to claim 1, wherein said at least one switching device is driven repeatedly with the first duty ratio, the target duty ratio, and the second duty ratio in this order.

4. A method according to claim 1, wherein said at least one switching device is driven with the target duty ratio, the first duty ratio, the target duty ratio, the second duty ratio, and the target duty ratio.

5. A method according to claim 1, wherein the DC/DC converter comprises three parallel phase arms, each of the three phase arms comprising an upper arm switching device and a lower arm switching device, said method comprising the steps of:

allotting the target duty ratio, the first duty ratio, and the second duty ratio to the three phase arms, respectively, and

turning on each of the three phase arms with the duty ratio allotted thereto.

6. A method of controlling a DC/DC converter apparatus by applying a method according to claim 1 to the DC/DC converter apparatus, which includes the DC/DC converter and a controller for driving said at least one switching device, the method comprising the steps of:

setting, with the controller, said target duty ratio,

setting, with the controller, the first and second duty ratios using the target duty ratio; and

driving, with the controller, said at least one switching device for ON times corresponding respectively to the target duty ratio, and the first and second duty ratios.

7. A method according to claim 6, wherein the DC/DC converter comprises a plurality of parallel phase arms connected between a first electric power device and a second electric power device, each of the phase arms comprising an upper arm switching device and a lower arm switching device, said method comprising the steps of:

alternately turning on, with the controller, the phase arms; and

when the controller turns on one of the phase arms, turning on either the upper arm switching device or the lower arm switching device, or alternately turning on the upper arm switching device and the lower arm switching device.

8. A method according to claim 7, further comprising the steps of:

when the controller alternately turns on the phase arms, alternately turning on the upper arm switching device and the lower arm switching device of one of the phase arms; and

thereafter alternately turning on the upper arm switching device and the lower arm switching device of a next one of the phase arms.

9. A method according to claim 8, further comprising the steps of:

when the controller alternately turns on the phase arms, turning on the upper arm switching device of the one of the phase arms;

thereafter turning on the lower arm switching device of the one of the phase arms;

thereafter turning on the upper arm switching device of the next one of the phase arms; and

thereafter turning on the lower arm switching device of the next one of the phase arms.

10. A method according to claim 7, wherein the phase arms are alternately turned on, each in one switching period.

11. A method according to claim 7, further comprising the steps of:

when the controller alternately turns on the upper arm switching devices and the lower arm switching devices, alternately turning on the upper arm switching devices and the lower arm switching devices with a dead time interposed therebetween, and alternately turning on the phase arms a dead time interposed therebetween.

12. A method according to claim 7, wherein the phase arms have respective midpoints connected to each other, and

wherein the DC/DC converter comprises a reactor or as many reactors as the number of phases inserted between the connected midpoints and the first electric power device or the second electric power device, the reactors having respective terminals connected to the midpoints, respectively, and other terminals connected to each other and to the first electric power device or the second electric power device.

13. A method according to claim 7, wherein the controller drives predetermined one of the phase arms for the ON time corresponding to the target duty ratio only, while driving the other phase arms for ON times corresponding to the prior and subsequent duty ratios only.

14. A method according to claim 6, wherein the DC/DC converter is connected between an electricity storage device serving as a first electric power device and a fuel cell serving as a second electric power device for driving a propulsive motor, which is energizable by an inverter for producing a regenerative voltage;

and

wherein the DC/DC converter increases a voltage of the electricity storage device and applies the increased voltage to the inverter, and reduces the regenerative voltage from the inverter and applies the reduced voltage to the electricity storage device when the propulsive motor is in a regenerative mode.

15. A method of controlling a driving operation of a vehicle by applying a method according to claim 14 to a vehicle having the DC/DC converter apparatus, the electricity storage device, the propulsive motor, and the fuel cell.

16. A method of controlling a driving operation of a vehicle by applying a method according to claim 6 to a vehicle having the DC/DC converter apparatus, a propulsive motor energizable by an inverter for producing a regenerative voltage, and an electricity storage device, the propulsive motor and the electricity storage device being connected to the DC/DC converter apparatus.

17. A method of controlling a fuel cell system by applying a method according to claim 6 to a fuel cell system having the DC/DC converter apparatus, a fuel cell connected to a load, and an electricity storage device, the fuel cell and the electricity storage device being connected to the DC/DC converter apparatus.

2. A method of driving a DC/DC converter for use between an electricity storage device and a fuel cell, comprising at least one switching device, said method comprising the steps of:

setting a target duty ratio depending on an ON time shorter than a minimum ON time of said switching device;

setting a first duty ratio and a second duty ratio based on the target duty ratio such that at least one of the first and second duty ratios corresponds to an ON time longer than the minimum ON time of said switching device; and

driving said switching device for ON times corresponding respectively to the target duty ratio, the first duty ratio and the second duty ratio, in a duty ratio range close to a directly coupled state, in which voltages at an end of the DC/DC converter connected to the electricity storage device and at another end of the DC/DC converter connected to the fuel cell are substantially equal to each other, wherein

one of the duty ratios is the maximum duty ratio and another one of the duty ratios is the minimum duty ratio; and

the remaining one of the duty ratios is a ratio between the maximum duty ratio and the minimum duty ratio.