Control apparatus of power converter circuit

• US 8,451,631 B2
• Filed: 10/31/2008
• Issued: 05/28/2013
• Est. Priority Date: 11/06/2007
• Status: Expired due to Fees

• Current Assignee: Nagasaki University
• Original Assignee: Nagasaki University
• Inventors: Kurokawa, Fujio
• Primary Examiner(s): Tran, Nguyen
• Application Number:
  US12/741,471
• Publication Number:
  US 20100277956A1
• Time in Patent Office: 1,670 Days
• Field of Search: 363/17, 363/18, 363/19, 363/20, 363/21.01, 363/21.02, 363/21.03, 363/21.04, 363/21.05, 363/132, 363/21.13
• US Class Current: 363/21.05
• CPC Class Codes: H02M 3/33507 with automatic control of the output voltage or current, e.g. flyback converters H02M3/33561, H02M3/33569 take precedence

Abstract

To detect a peak time of an exciting current of a transformer, a primary current corresponding to the peak time, or a variation time of the primary voltage, and to switch a switch after expiration of a predetermined period from the peak time, after the peak time occurs. A control apparatus 1 is applied to a power conversion circuit 2 which includes a switch circuit 23 including one switch or a plurality of switches and a transformer 21. The control apparatus includes: an output voltage detector 11 detecting a value of an output voltage of the power conversion circuit; an exciting current peak time generator 12 detecting a peak time of an exciting current of the transformer; a timing generator 13 generating a switching timing of the one switch or the plurality of switches. The timing generator 13 generates the switching timing of the one switch or the plurality of switches on the basis of the output voltage and the peak time.

Claims

1. A control apparatus applied to a resonance type power conversion circuit comprising a transformer and a switch circuit comprising one switch or a plurality of switches, the control apparatus comprising:

an output voltage detector detecting a value of an output voltage of the power conversion circuit;

an exciting current peak time detecting unit to detect a peak time of an exciting current of the transformer, the exciting current peak time detector comprising;

a peak time detector data buffer to store a value of a primary current of the transformer sequentially; and

a peak time detector to detect the exciting current peak time based on data stored in the peak time detector data buffer; and

a timing generator to generate switch timing signals on the basis of the output voltage and the peak time, the timing generator comprising;

a timing generator data buffer to store an output voltage of the power conversion circuit;

an average voltage calculator to calculate an average of the output voltage based on data stored in the timing generator data buffer;

a deviation calculator to detect a deviation between an output of the average voltage calculator and a reference voltage and to calculate a time corresponding to the deviation; and

a timing generating circuit to generate an off timing signal for a first switch after passage of the calculated time following detection of the peak time by the peak time detector and an on timing signal for a second switch after a reverse voltage is applied to the second switch after the first switched is turned off and before a forward voltage is applied to the second switch.

2. The control apparatus according to claim 1, wherein the exciting current peak time detecting unit detects the peak time on the basis of a variation in a primary current or a primary voltage of the transformer.

3. The control apparatus according to claim 1, wherein at least one of the output voltage detector, the exciting current peak time detecting unit, and the timing generator comprises an analog circuit or a digital circuit.