Bi-directional switched-capacitor based voltage converter

• US 6,304,068 B1
• Filed: 04/20/2000
• Issued: 10/16/2001
• Est. Priority Date: 04/20/2000
• Status: Expired due to Term

• Current Assignee: City University of Hong Kong
• Original Assignee: City University of Hong Kong
• Inventors: Chung, Shu-Hung Henry, Hui, Shu-Yuen Ron
• Primary Examiner(s): Riley, Shawn
• Application Number:
  US09/553,116
• Time in Patent Office: 544 Days
• Field of Search: 323/288, 323/284, 323/285, 323/224, 323/225, 323/233, 323/266, 323/282
• US Class Current: 323/288
• CPC Class Codes: H02M 3/07 using capacitors charged and discharged alternately by semiconductor devices with control electrode , e.g. charge pumps
• CPC Class Codes: H02M 3/072 adapted to generate an output voltage whose value is lower than the input voltage

Abstract

A bidirectional switched-capacitor power converter has a first step-up mode and a second step-down mode. The converter includes a capacitor in which in both modes is charged during a first switch topology and then discharged during a second switch topology. Two converters operating out of phase may be disposed in parallel to enable continuous power conversion.

Claims

1. A bidirectional switched-capacitor power converter, wherein said power converter comprises a single circuit configuration having two modes of operation, a first mode providing for energy conversion from a high-voltage side to a low-voltage side, and a second mode providing for energy conversion from a low-voltage side to a high-voltage side, wherein said circuit comprises a capacitor serving as an energy storage element between the low-voltage side and the high-voltage side and wherein each said mode comprises a first topology wherein said capacitor is charged and a second topology wherein said capacitor is discharged.

2. A converter as claimed in claim 1 wherein when said converter is operated in said first mode said capacitor is charged from said high-voltage side in said first topology and is discharged to said low-voltage side in said second topology.

3. A converter as claimed in claim 1 wherein when said converter is opreated in said second mode said capacitor is charged from said low-voltage side in said first topology and is discharged to said high-voltage side in said second topology.

4. A converter as claimed in claim 1 wherein means are provided to switch said converter from each said first topology to each said second topology.

5. A converter as claimed in claim 4 wherein said converter comprises a plurality of switches and each said topology corresponds to a different switch configurations said topology switching means comprising means for changing the configuration of said switches.

6. A converter as claimed in claim 1 wherein means are provided for controlling the conversion factor of said converter by controlling the charging of said capacitor.

7. A converter as claimed in claim 6 wherein said capacitor is charged through a MOSFET switch.

8. A converter as claimed in claim 7 wherein said charging of said capacitor is controlled by controlling the charging current by means of applying a control voltage to the gate-source of said MOSFET switch.