Output regulating device for regulating output of electric power source depending on input therefrom

• US 7,279,878 B2
• Filed: 09/03/2004
• Issued: 10/09/2007
• Est. Priority Date: 09/04/2003
• Status: Expired due to Fees

• Current Assignee: Taiyo Yuden Company Limited (Taiyo Yuden Co)
• Original Assignee: Taiyo Yuden Company Limited (Taiyo Yuden Co)
• Inventors: Hosaka, Yasuo, Ootani, Mitsuaki
• Primary Examiner(s): Riley; Shawn
• Application Number:
  US10/933,796
• Publication Number:
  US 20050052222A1
• Time in Patent Office: 1,131 Days
• Field of Search: 323/299, 323/222, 323/285, 307/150
• US Class Current: 323/285
• CPC Class Codes: H02M 3/156 with automatic control of output voltage or current, e.g. switching regulators
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

If an input voltage to an output control device is above a lower limit value, the output control device operates in a constant voltage control mode for maintaining an output voltage at a substantially constant voltage. If the input voltage of the output control device falls below the lower limit value, the output voltage is controlled to be lower than the constant voltage in the constant voltage control mode, and the output control device operates in a lower limit value sustaining mode for maintaining the input voltage at the lower limit value. Then, the output control device shifts to a current increasing mode in which the output current rises as the output voltage falls.

Claims

1. An output control device for an electric power source, comprising:

a converter circuit for converting an input voltage from the electric power source to an output voltage; and

an input detector circuit for detecting, monitoring, and comparing with a reference value an input from the electric power source,

wherein the converter circuit has a constant voltage control mode under which the output voltage is maintained, and a lower limit value sustaining mode under which a lower limit value of the input voltage is maintained at a predetermined voltage value, said lower limit value sustaining mode being activated when an output from the input detector circuit is compared with and is lower than a predetermined set reference value.

2. An output control device according to claim 1, wherein the input detector circuit detects at least one of an input voltage, an input current, and an input power to the output control device from the electric power source.

3. An output control device according to claim 1, wherein the lower limit value of the input voltage is maintained at the predetermined value by varying the output voltage in the lower limit value sustaining mode.

4. An output control device according to claim 1, wherein an output current to a load is heightened by maintaining the lower limit value of the input voltage at the predetermined value in the lower limit value sustaining mode.

5. An output control device according to claim 1, wherein the converter circuit further has a constant voltage control mode for controlling the output voltage to a constant value by detecting the output voltage, and

wherein the converter circuit switches between the constant voltage control mode and the lower limit value sustaining mode in response to the detected output of the input detector circuit.

6. An output control device for an electric power source, comprising

a converter circuit for converting an input voltage from the electric power source to an output voltage;

and

an input detector circuit for monitoring and detecting a variation in an input from the electric power source,

wherein the converter circuit has a constant voltage control mode under which the output voltage is maintained, and a current increasing mode in which an output current is increased while the input voltage is maintained at a predetermined value, said current increasing mode being activated when the variation in the input detected by the input detector circuit is compared with and exceeds a predetermined value.

7. An output control device according to claim 6, wherein the input detector circuit detects at least one of a variation in an input voltage, a variation in an input current, and a variation in an input power from the electric power source.

8. An output control device according to claim 6, wherein the converter circuit has a constant voltage control mode in which the converter circuit detects the output voltage to control the output voltage to a constant value, and

wherein the converter circuit switches between the constant voltage control mode and the current increasing mode in response to the detected output from the input detector circuit.

9. An output control device for an electric power source, comprising

a converter circuit for converting an input voltage from the electric power source to an output voltage;

a lower limit detector circuit for monitoring the input voltage from the electric power source and outputting a predetermined signal when the input voltage from the electric power source falls below a predetermined threshold value; and

an output voltage detector circuit for detecting the output voltage,

wherein the converter circuit controls a conversion condition under which the input voltage is converted to the output voltage based on the output voltage detected by the output voltage detector circuit and the output from the lower limit detector circuit.

10. An output control device for an electric power source, comprising

a converter circuit for converting an input voltage from the electric power source to an output voltage;

an upper limit detector circuit for monitoring an input current from the electric power source and outputting a predetermined signal when the input current from the electric power source rises above a predetermined threshold value; and

an output voltage detector circuit for detecting the output voltage,

wherein the converter circuit controls a conversion condition under which the input voltage is converted to the output voltage based on the output voltage detected by the output voltage detector circuit and the output from the upper limit detector circuit.

11. An output control device for an electric power source, comprising:

a converter circuit for converting an input voltage from the electric power source to an output voltage, said converter circuit comprising a switching controller controlling the output voltage at a substantially constant value by inputting therein a set reference voltage and a signal indicative of the output voltage in a constant voltage control mode; and

an input detector circuit for detecting an input indicative of a change of the input voltage from the electric power source, said input detector circuit maintaining the input voltage at a predetermined value with reference to a set lower limit value of voltage and the detected input in a lower limit value sustaining mode,

wherein the switching controller receives an output from the input detector and controls the output voltage at a value lower than the reference voltage when in the lower limit sustaining mode.

12. An output control device according to claim 11, wherein the detected input is selected from the group consisting of an input voltage, an input current, an input power, a variation of the input voltage, a variation of the input current, and a variation of the input power from the electric power source.

13. An output control device according to claim 12, wherein the switching controller comprises:

a differential amplifier which compares the reference voltage and a signal indicative of the output voltage modified by the output from the input detector to output a voltage difference; and

a switching control circuit and a filed-effect transistor, said switching control circuit turning on and off the field-effect transistor in response to the voltage difference to control the output voltage from the output control device.

14. An output control device according to claim 13, wherein the input detector is configured to detect the input voltage from the electric power source and compare the input voltage and the lower limit value of voltage.

15. An output control device according to claim 13, wherein the input detector is configured to detect the input current from the electric power source and compare the input current and an upper limit value of current corresponding to the lower limit value of voltage.

16. An output control device according to claim 13, wherein the input detector is configured to detect the input voltage and a variation of the input voltage from the electric power source, compare the input voltage and the lower limit value of voltage, and compare the variation of the input voltage and a set variation of the input voltage.

17. An output control device according to claim 13, wherein the input detector is configured to detect the input current and a variation of the input current from the electric power source, compare the input current and an upper limit value of current corresponding to the lower limit value of voltage, and compare the variation of the input current and a set variation of the input current.

18. An output control device according to claim 11, wherein the converter circuit is configured to boost the input voltage to the output voltage.

19. An output control device for an electric power source, comprising:

a converter circuit for converting an input voltage from the electric power source to an output voltage; and

an input detector circuit for detecting, monitoring, and comparing with a reference value an input from the electric power source, said input detector circuit including a comparator which receives the input from the electric power,

wherein the converter circuit has a constant voltage control mode under which the output voltage is maintained, and a lower limit value sustaining mode under which a lower limit value of the input voltage is maintained at a predetermined voltage value, said lower limit value sustaining mode being activated when an output from the comparator of the input detector circuit is compared with and is lower than a predetermined set reference value.