Common-ground isolation hybrid dual-output converter
By designing a common ground isolation hybrid dual output converter, using transformers to replace filter inductors, realizing non-isolated and isolated two-channel outputs, the problem of traditional Forward converters requiring additional design of magnetic reset windings is solved, and electrically isolated outputs are achieved and design complexity and cost are reduced.
Patent Information
- Application Number
- CN202510023110.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-07
- Publication Date
- 2025-05-16
AI Technical Summary
Traditional Forward converters require additional design of magnetic reset windings to solve magnetic saturation problems, increasing design complexity and cost while lacking electrically isolated outputs.
A common ground isolation hybrid dual output converter is designed to replace the filter inductor by transformer to achieve non-isolated and isolated outputs, and the design of magnetic reset winding is avoided by the combination of freewheeling diode and rectifier diode.
The electrically isolated output of the converter is realized, reducing design complexity and cost, and is suitable for more application scenarios.
Smart Images
Figure CN120016836A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of converters, and in particular to a common ground isolated hybrid dual-output converter. Background Art
[0002] As an important branch of the power electronics field, the switching power supply technology has a promising future and is of great importance. The earliest linear power supply can provide a constant DC power output for the load at the expense of efficiency. The rise and development of open source power supply technology has replaced the linear power supply, and its efficiency, reliability and power density have all been qualitatively improved.
[0003] The forward converter is an isolated buck converter, and its voltage output terminal has the characteristics of electrical isolation, which increases the safety of the system. However, the traditional forward converter needs to add an additional magnetic reset winding to solve the problem of transformer magnetic saturation, which increases the design complexity and cost of the transformer. Summary of the invention
[0004] In view of the defects of the prior art, the present invention provides a converter that does not require the design of a magnetic reset winding and can achieve two-way output, thereby solving the complexity problem of the traditional forward converter that requires the additional design of a magnetic reset winding, as well as the disadvantages of a single output and no electrical isolation.
[0005] In order to achieve the above object, the present invention provides a common ground isolated hybrid dual-output converter, including: a switch tube S, a transformer T, a freewheeling diode D1, a first capacitor C1, a rectifier diode D2, and a second capacitor C2;
[0006] The drain of the switch tube S is connected to the DC power supply V in The positive electrode of the transformer is connected, and the source electrode thereof is connected to the cathode of the freewheeling diode D1 and the first end of the primary side of the transformer T; the second end of the primary side of the transformer T is connected to the first end of the first capacitor C1 to form a non-isolated output voltage V o1 The positive end of the freewheeling diode D1 is connected to the DC power supply V in The input negative electrode and the second end of the first capacitor C1 are connected to form a non-isolated output voltage V o1 The negative end of the transformer T secondary side first end is connected to the anode of the rectifier diode D2; the cathode of the rectifier diode D2 is connected to the first end of the second capacitor C2 to form an isolated output voltage V o2 The second end of the second capacitor C2 is connected to the second end of the secondary side of the transformer T to form an isolated output voltage V o2 The negative terminal.
[0007] Furthermore, the DC power supply V inConnected in series with the switch tube S, the primary side of the transformer T, and the first capacitor C1 in sequence to form a first closed loop;
[0008] The DC power supply V in In sequence with the switch tube S, the primary side of the transformer T, and the first load R at the non-isolated output end L1 The second closed loop is formed in series;
[0009] The secondary side of the transformer T is connected in series with the rectifier diode D2 and the second capacitor C2 in sequence to form a third closed loop;
[0010] The secondary side of the transformer T is connected in sequence to the rectifier diode D2, the second load R at the isolated output end L2 The fourth closed loop is formed in series;
[0011] The freewheeling diode D1 is connected in series with the primary side T of the transformer and the first capacitor C1 in sequence to form a first freewheeling loop;
[0012] The freewheeling diode D1 is connected in sequence to the primary side T of the transformer, the first load R of the non-isolated output end L1 The second freewheeling circuit is formed in series;
[0013] The second capacitor C2 and the second load R L2 The third freewheeling circuit is formed in series;
[0014] The first capacitor C1 and the first load R at the non-isolated output end L1 The fourth freewheeling loop is formed in series.
[0015] Furthermore, the first capacitor C1 and the second capacitor C2 are both non-polar thin film capacitors.
[0016] Furthermore, the switch tube S is a metal oxide semiconductor field effect transistor or an insulated gate bipolar transistor.
[0017] Beneficial effects of the present invention:
[0018] 1. The present invention solves the drawbacks of the traditional buck converter with a single output and no electrical isolation. A transformer is used to replace the filter inductor, so that it has an additional output that meets the electrical isolation requirement, which is suitable for more application scenarios.
[0019] 2. The isolated output of the converter of the present invention is similar to the output of the forward converter, but does not require the design of a magnetic reset circuit, thereby optimizing the design of the transformer.
[0020] 3. The converter of the present invention can realize soft turning on of the secondary rectifier diode in CCM state, soft starting of the secondary rectifier diode and soft turning off of the freewheeling diode in DCM state. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 Schematic diagram of a common ground isolated hybrid dual-output converter circuit according to an embodiment of the present invention.
[0022] Figure 2 Schematic diagram of the topological structure of the common ground isolated hybrid dual-output converter in steady state according to an embodiment of the present invention. DETAILED DESCRIPTION
[0023] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described below in conjunction with the accompanying drawings. The described embodiments should not be regarded as limiting the present application. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.
[0024] In the following description, reference is made to “some embodiments”, “one or more embodiments”, which describe a subset of all possible embodiments, but it can be understood that “some embodiments”, “one or more embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.
[0025] In the following description, the terms "first\second\third" are only used to distinguish similar objects and do not represent a specific ordering of the objects. It can be understood that "first\second\third" can be interchanged with a specific order or sequence where permitted, so that the embodiments of the present application described here can be implemented in an order other than that shown or described.
[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein are only for the purpose of describing the embodiments of this application and are not intended to limit this application.
[0027] This embodiment provides a common ground isolation hybrid dual output converter. Figure 1 As shown, including: DC power supply V in , switch tube S, transformer T, freewheeling diode D1, first capacitor C1, first load R L1 , rectifier diode D2, second capacitor C2, second load R L2 .
[0028] In the embodiment of the present invention, the DC power supply V in It can be photovoltaic cells, automotive batteries, fuel cells, etc.
[0029] The drain of the switch tube S is connected to the DC power supply V inThe positive electrode of the transformer is connected, and its source is connected to the cathode of the freewheeling diode D1 and the first end of the primary side of the transformer T; the second end of the primary side of the transformer T is connected to the first end of the first capacitor C1 to form a non-isolated output voltage V o1 The positive terminal (first load R L1 The first end of the freewheeling diode D1 is connected to the DC power supply V in Input negative terminal (first load R L1 The second end of the first capacitor C1 is connected to form a non-isolated output voltage V o1 The negative end of the transformer T secondary side first end is connected to the anode of the rectifier diode D2; the cathode of the rectifier diode D2 is connected to the first end of the second capacitor C2 to form an isolated output voltage V o2 The positive terminal (second load R L2 The second end of the second capacitor C2 is connected to the second end of the secondary side of the transformer T to form an isolated output voltage V o2 The negative terminal (second load R L2 the second end of the
[0030] Then the DC power supply V in The first closed loop is formed by sequentially connecting in series with the switch tube S, the primary side of the transformer T and the first capacitor C1.
[0031] DC power supply V in In sequence with the switch tube S, the primary side of the transformer T, and the first load R L1 The series connection forms a second closed loop.
[0032] The secondary side of the transformer T is connected in series with the rectifier diode D2 and the second capacitor C2 in sequence to form a third closed loop.
[0033] The secondary side of the transformer T is connected in sequence to the rectifier diode D2 and the second load R L2 The series connection forms a fourth closed loop.
[0034] The freewheeling diode D1 is sequentially connected in series with the primary side of the transformer T and the first capacitor C1 to form a first freewheeling loop.
[0035] The freewheeling diode D1 is connected to the primary side of the transformer T and the first load R L1 The series connection forms a second freewheeling loop.
[0036] The second capacitor C2 and the second load R L2 The series connection forms the third freewheeling loop.
[0037] The first capacitor C1 and the first load R L1 The fourth freewheeling loop is formed in series.
[0038] In the embodiment of the present invention, the first capacitor and the second capacitor are both filter capacitors, which can be electrolytic capacitors or non-polar film capacitors. The switch tube S1 is a metal oxide semiconductor field effect transistor (MOSFET) tube or an insulated gate bipolar transistor (IGBT).
[0039] The converter of the embodiment of the present invention realizes dual outputs, and the transformer does not need to consider the magnetic reset winding in the design, and only needs to design the primary-secondary turns ratio, thereby optimizing the transformer design.
[0040] In order to more clearly illustrate the embodiment of the present invention, the principle of the present invention is described in detail below. The working mode of the converter when working in CCM mode is as follows: Figure 2 The specific description is as follows:
[0041] like Figure 2 As shown in (a), when the switch tube S is turned on, the DC power supply V in Through the first capacitor C1 to the first load R L1 Energy supply, transformer T transfers energy from the primary side to the secondary side, and the primary current i of transformer T P The secondary rectifier diode D2 is turned on, and the output is filtered by the second capacitor C2 and sent to the second load R L2 Energy is supplied and the freewheeling diode D1 is cut off.
[0042] like Figure 2 As shown in (b), when the switch tube S is turned off, the primary side of the transformer T generates a voltage with the opposite polarity to the original voltage, the secondary side rectifier diode D2 is cut off, and the capacitor C2 is connected to the second load R L2 The freewheeling diode D1 is turned on, and the first capacitor C1 discharges to the first load R L1 Energy supply, transformer T primary current i P Linear decrease.
[0043] It can be seen that here the transformer T does not need to be designed with a magnetic reset winding like the Forward, because the reverse voltage required for the magnetic reset is provided by the output of the non-isolated end.
[0044] The above is only an embodiment of the present application and is not intended to limit the protection scope of the present application. Any modification, equivalent replacement and improvement made within the spirit and scope of the present application are included in the protection scope of the present application.
Claims
1. A common ground isolated hybrid dual output converter, characterized in that: include: Switch tube S, transformer T, freewheeling diode D1, first capacitor C1, rectifier diode D2, second capacitor C2; The drain of the switch tube S is connected to the DC power supply V in The positive electrode of the transformer is connected, and the source electrode thereof is connected to the cathode of the freewheeling diode D1 and the first end of the primary side of the transformer T; the second end of the primary side of the transformer T is connected to the first end of the first capacitor C1 to form a non-isolated output voltage V o1 The positive end of the freewheeling diode D1 is connected to the DC power supply V in The input negative electrode and the second end of the first capacitor C1 are connected to form a non-isolated output voltage V o1 The negative end of the transformer T secondary side first end is connected to the anode of the rectifier diode D2; the cathode of the rectifier diode D2 is connected to the first end of the second capacitor C2 to form an isolated output voltage V o2 The second end of the second capacitor C2 is connected to the second end of the secondary side of the transformer T to form an isolated output voltage V o2 The negative terminal.
2. The common ground isolated hybrid dual output converter according to claim 1, characterized in that: The DC power supply V in Connected in series with the switch tube S, the primary side of the transformer T, and the first capacitor C1 in sequence to form a first closed loop; The DC power supply V in In sequence with the switch tube S, the primary side of the transformer T, and the first load R at the non-isolated output end L1 The series connection forms a second closed loop; The secondary side of the transformer T is connected in series with the rectifier diode D2 and the second capacitor C2 in sequence to form a third closed loop; The secondary side of the transformer T is connected in sequence to the rectifier diode D2, the second load R at the isolated output end L2 The fourth closed loop is formed in series; The freewheeling diode D1 is connected in series with the primary side of the transformer T and the first capacitor C1 in sequence to form a first freewheeling loop; The freewheeling diode D1 is connected in sequence to the primary side T of the transformer, the first load R of the non-isolated output end L1 The second freewheeling circuit is formed in series; The second capacitor C2 and the second load R L2 The third freewheeling circuit is formed in series; The first capacitor C1 and the first load R at the non-isolated output end L1 The fourth freewheeling loop is formed in series.
3. The common ground isolated hybrid dual output converter according to claim 1, characterized in that: The first capacitor C1 and the second capacitor C2 are both non-polar thin film capacitors.
4. The common ground isolated hybrid dual output converter according to claim 1, characterized in that: The switch tube S is a metal oxide semiconductor field effect transistor or an insulated gate bipolar transistor.