Soft Switching Converter with Dual Transformer by Steering the Magnetizing Current

• US 20150256087A1
• Filed: 11/07/2014
• Published: 09/10/2015
• Est. Priority Date: 11/07/2013
• Status: Abandoned Application

• Current Assignee: Rompower Energy Systems, Inc.
• Original Assignee: Rompower Energy Systems, Inc.
• Inventors: Jitaru, Ionel
• Application Number:
  US14/535,993
• Publication Number:
  US 20150256087A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01F 2027/408 Association with diode or rectifier
• CPC Class Codes: H01F 3/14 Constrictions; Gaps, e.g. air-gaps in magnetic shunt paths H01F3/12
• CPC Class Codes: H02M 1/0058 by employing soft switching techniques, i.e. commutation of transistors when applied voltage is zero or when current flow is zero using an auxiliary actively switched resonant commutation circuit connected to an intermediate DC voltage or between two push-pull branches of an inverter bridge H02M7/4811; in resonant inverters H02M7/4815; in inverters operating from a resonant DC source H02M7/4826
• CPC Class Codes: H02M 3/33546 with automatic control of the output voltage or current H02M3/33561 takes precedence
• CPC Class Codes: H02M 3/33592 having a synchronous rectifier circuit or a synchronous freewheeling circuit at the secondary side of an isolation transformer
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A design and control method is shown to create soft transition in dual transformer half bridge or full bridge topology by controlling the magnetizing current in both transformers to cross zero level and allows soft switching on all the switching elements.

Claims

1. A design and control method for a converter with dual transformers and synchronous rectifiers, comprising using the magnetizing current in both transformers to shape the current through the synchronous rectifiers to become negative so that soft transitions are obtained in all switching devices in the converter.

3. The design and control method of any of claims 1 or 2 wherein the dual transformers of the converter are integrated on the same magnetic core.

4. The design and control method of claim 3 wherein the magnetizing current in each set of dual transformers is tailored through modulation in frequency in such way that the claimed conditions of claims 1 or 2, respectively, do occur over a predetermined range of input and output loading conditions.

5. The design and control method of claim 3 wherein the power transfer from primary to the secondary is controlled by turning off periodically some or all the switching elements for a determined period of time.

6. The design and control method of claim 3 using a controller that controls all switching devices of the converter to produce optimum frequency for controlling a predetermined power parameter of the converter.

7. The design and control method of any of claims 1 or 2 using a controller that controls all switching devices of the converter to produce optimum frequency for controlling a predetermined power parameter of the converter.

8. The design and control method of any of claims 1 or 2 wherein the magnetizing current in each set of dual transformers is tailored through modulation in frequency in such way that the claimed conditions of claims 1 or 2, respectively do occur over a predetermined range of input and output loading conditions.

9. The design and control method of any of claims 1 or 2 wherein the power transfer from primary to the secondary is controlled by turning off periodically some or all the switching elements for a determined period of time.

2. A design and control method for a converter with dual transformers and at least two primary switching devices and at least two synchronous rectifiers in the secondary wherein each of the primary switching device is off when a correspondent synchronous rectifier is on, wherein the amount of negative current through the synchronous rectifier and the time between turn off of the synchronous rectifier and turn on of the correspondent primary switching device is tailored that the correspondent primary switching device turns on at zero voltage switching conditions.