Resonant converter and synchronous rectification converter circuit thereof

Patent metadata

Field	Value
Publication number	US-10008955-B2
Application number	US-201715460534-A
Country	US
Kind code	B2
Filing date	Mar 16, 2017
Priority date	Apr 16, 2014
Publication date	Jun 26, 2018
Grant date	Jun 26, 2018

Abstract

A synchronous rectification converter circuit is provided, including three transformer secondary-windings, three current transformers, a synchronous rectification switching circuit, a diode rectification circuit, and a control circuit. Each of three current transformers includes a primary-winding and secondary-winding. The three transformer secondary-windings and the three current transformer primary-windings are alternately connected in series to form a first triangular structure circuit. Three vertices of the first triangular structure circuit are connected to the synchronous rectification switching circuit. The three current transformer secondary-windings are connected in series to form a second triangular structure circuit. Three vertices of the second triangular structure circuit are connected to the diode rectification circuit. The diode rectification circuit is connected to the control circuit and the synchronous rectification switching circuit is connected to the control circuit.

First claim

What is claimed is:

1. A synchronous rectification converter circuit, comprising:
a first triangle structure circuit comprising three branches, with each branch comprising a transformer secondary-side winding and a current transformer primary-side winding, wherein the transformer secondary-side winding and the current transformer primary-side winding are connected in series;
a second triangle structure circuit comprising three branches; with each branch comprising a current transformer secondary-side winding;
a synchronous rectification switching circuit including a first node, a second node and a third node, wherein the three vertices of the first triangle structure circuit are respectively connected to the first node, the second node and the third node of the synchronous rectification switching circuit;
a diode rectification circuit including a fourth node, a fifth node and a sixth node; wherein the three vertices of the second triangle structure circuit are respectively connected to the fourth node, the fifth node and the sixth node; and
a control circuit including a diode voltage sampling circuit and a controller, wherein the diode rectification circuit is connected to the diode voltage sampling circuit, wherein the diode voltage sampling circuit is connected to the controller, and wherein the controller is connected to the synchronous rectification switching circuit;
wherein the diode voltage sampling circuit of the control circuit detects voltage of a diode included in the diode rectification circuit to acquire a diode voltage value and sends the diode voltage value to the controller; and
the controller determines whether a current flows through a switching transistor in the synchronous rectification switch circuit, which is corresponding to the diode included in the diode rectification circuit; wherein when a current flows through the switching transistor, the controller sends a control signal to the switching transistor to make the switching transistor open.

2. The synchronous rectification converter circuit according to claim 1 , the control circuit also includes a resistance;
the diode rectification circuit includes a first to third groups of diodes;
the first to third groups of diodes are connected in parallel with the ends of the resistance;
the first group of diodes includes two diodes and a fourth node between the two diodes; the two diodes of the first group diodes are connected in series;
the second group of diodes includes two diodes and a fifth node between the two diodes; the two diodes of the second group diodes are connected in series;
the third group of diodes includes two diodes and a sixth node between the two diodes; the two diodes of the third group diodes are connected in series.

3. The synchronous rectification converter circuit according to claim 2 , wherein:
a dotted terminal of the transformer secondary-side winding is connected to a dotted terminal of the current transformer primary-side winding, an undotted terminal of the transformer secondary-side winding is connected to an undotted terminal of a current transformer primary-side winding of another branch.

4. The synchronous rectification converter circuit according to claim 2 , wherein the first group of diodes comprises a first diode and a second diode; the second group of diodes comprises a third diode and a fourth diode; the third group of diodes comprises a fifth diode and a sixth diode; a positive electrode of the first diode is connected to a negative electrode of the second diode; the positive electrode of the first diode is further connected to the dotted terminal of the first current transformer secondary-side winding; a negative electrode of the first diode is connected to a first end of the resistor; a positive electrode of the second diode is connected to a second end of the resistor; a positive electrode of the third diode is connected to a negative electrode of the fourth diode; the positive electrode of the third diode is further connected to the dotted terminal of the second current transformer secondary-side winding; a negative electrode of the third diode is connected to the first end of the resistor; a positive electrode of the fourth diode is connected to the second end of the resistor; a positive electrode of the fifth diode is connected to a negative electrode of the sixth diode; the positive electrode of the fifth diode is further connected to the dotted terminal of the third current transformer secondary-side winding; a negative electrode of the fifth diode is connected to the first end of the resistor; and a positive electrode of the sixth diode is connected to the second end of the resistor.

5. The synchronous rectification converter circuit according to claim 4 , wherein the controller comprises a control circuit and a first to a sixth comparing circuits; the first to the sixth comparing circuits respectively correspond to the first to the sixth diodes; two input ends of the first to the sixth comparing circuits are respectively connected to a positive electrode and a negative electrode of a corresponding diode, and the first to the sixth comparing circuits are configured to compare sampled voltages of the positive electrode and the negative electrode of the corresponding diode; an output end of the first to the sixth comparing circuits is connected to the control circuit, to output a comparison result to the control circuit; and the control circuit is connected to each switch component in the first to the third groups of switch components and determines the on-off state of the corresponding diode according to the comparison result, to control the on-off state of switch components corresponding to the corresponding diode.

6. The synchronous rectification converter circuit according to claim 2 , wherein the synchronous rectification converter circuit further comprises a filter capacitor connected between the first end and the second end of the resistor.

7. A resonant converter, comprising:
a synchronous rectification circuit comprising a first triangle structure circuit, a second triangle structure circuit, a synchronous rectification switching circuit, a diode rectification circuit and control circuit; and
a synchronous rectification converter circuit that is configured to control the synchronous rectification circuit,
wherein the first triangle structure circuit comprises three branches; each branch comprises a transformer secondary-side winding and a current transformer primary-side winding; wherein the transformer secondary-side winding and the current transformer primary-side winding are connected in series;
wherein the second triangle structure circuit comprises three branches; each branch comprises a current transformer secondary-side winding;
the synchronous rectification switching circuit includes a first node, a second node and a third node; the three vertices of the first triangle structure circuit are respectively connected to the first node, the second node and the third node;
the diode rectification circuit includes a fourth node, a fifth node and a sixth node; the three vertices of the second triangle structure are respectively connected to the fourth node, the fifth node and the sixth node;
the control circuit includes a diode voltage sampling circuit and a controller; the diode rectification circuit is connected to the diode voltage sampling circuit; the diode voltage sampling circuit is connected to the controller; the controller is connected to the synchronous rectification switching circuit;
the diode voltage sampling circuit detects voltage of a diode included in the diode rectification circuit to acquire a diode voltage and sends the diode voltage value to the controller;
the controller determines whether a current flows through a swit

Assignees

• Huawei Tech Co Ltd

Inventors

• Chen Wenbin
• Zhou Kui

Classifications

• H02M3/33592 Primary

  having a synchronous rectifier circuit or a synchronous freewheeling circuit at the secondary side of an isolation transformer · CPC title

• H02M7/06 Primary

  using discharge tubes without control electrode or semiconductor devices without control electrode · CPC title

• H02M2007/2195

  Electricity · mapped topic

• Y02B70/1475

  Cross-Sectional Technologies · mapped topic

• Y02B70/1441

  Cross-Sectional Technologies · mapped topic