WO2021003647A1

WO2021003647A1 - Voltage conversion circuit of integrated vehicle-mounted charger

Info

Publication number: WO2021003647A1
Application number: PCT/CN2019/095148
Authority: WO
Inventors: 陈丽君; 赵德琦; 吴壬华
Original assignee: 深圳欣锐科技股份有限公司
Priority date: 2019-07-08
Filing date: 2019-07-08
Publication date: 2021-01-14
Also published as: CN111557074A

Abstract

Disclosed by the present application is a voltage conversion circuit of an integrated vehicle-mounted charger, comprising an input circuit, a transformer and an output circuit; the input circuit comprises a first sub-input circuit and a second sub-input circuit; the transformer comprises a first primary winding, a second primary winding and a secondary winding; the input circuit is connected to the transformer, the transformer is connected to the output circuit, the first sub-input circuit is in series connection with the second sub-input circuit, the first-sub input circuit is connected to a first port and second port of the first primary winding, the second sub-input circuit is connected to a first port and second port of the second primary winding, and the secondary winding is connected to the output circuit. According to the embodiments of the present application, the range of adaptation of the input voltage of a circuit may be improved, and the requirements of low voltage and large current output are met.

Description

Integrated voltage conversion circuit of vehicle charger

Technical field

This application relates to the technical field of circuit structures, and in particular to a voltage conversion circuit integrated with an on-board charger.

Background technique

LLC resonant circuit is a circuit topology suitable for occasions with high conversion power, low output voltage, but large output current. High power conversion efficiency and power density, as well as low electromagnetic interference characteristics, make it widely used in various electronic products. At present, there are mainly two common LLC resonant circuits in the voltage conversion circuit of the integrated vehicle charger: a half-bridge LLC resonant circuit and a full-bridge LLC resonant circuit.

In the prior art, whether it is a half-bridge LLC resonant circuit or a full-bridge LLC resonant circuit, there is such a problem that it cannot meet the requirement of an integrated on-board charger for the increasingly higher input voltage of the circuit.

Summary of the invention

The embodiment of the present application provides a voltage conversion circuit integrated with an on-board charger, which is used to increase the adaptation range of the input voltage of the circuit and meet the requirements of low voltage and large current output.

In a first aspect, an embodiment of the present application provides a voltage conversion circuit integrated with a vehicle charger, including an input circuit, a transformer, and an output circuit. The input circuit includes a first sub-input circuit and a second sub-input circuit, and the transformer includes The first primary winding, the second primary winding and the secondary winding, where:

The input circuit is connected to the transformer, the transformer is connected to the output circuit, the first sub-input circuit is connected in series with the second sub-input circuit, and the first sub-input circuit is connected to the first original circuit. The first port and the second port of the side winding are connected, the second sub-input circuit is connected with the first port and the second port of the second primary winding, and the secondary winding is connected with the output circuit;

The high voltage signal passes through the first sub-input circuit and the second sub-input circuit to generate a first electrical signal and a second electrical signal, respectively, and the first electrical signal passes through the first primary winding of the transformer to generate a first electrical signal. Magnetic flux, the second electrical signal passes through the second primary winding of the transformer to generate a second magnetic flux, the direction of the first magnetic flux is the same as the direction of the second magnetic flux, the first magnetic flux and the second magnetic flux The magnetic flux superimposes through the secondary winding of the transformer to generate an induced electromotive force, and the induced electromotive force generates a low voltage signal through the output circuit.

In an embodiment of the present application, the first sub-input circuit includes a first capacitor, a second capacitor, a first transistor, a second transistor, a third transistor, a fourth transistor, and a first inductor, wherein:

The first port of the first capacitor is connected to the drain of the first transistor and the drain of the third transistor, the source of the first transistor is connected to the drain of the second transistor, and the The source of the third transistor is connected to the drain of the fourth transistor and the first port of the second capacitor, the second port of the second capacitor is connected to the first port of the first inductor, and the The first port of the first sub-input circuit is connected to the second port of the first inductor, and the second port of the first sub-input circuit is connected to the source of the first transistor and the drain of the second transistor Connected, the third port of the first sub-input circuit is connected to the second port of the first capacitor, the source of the second transistor and the source of the fourth transistor, the first sub-input circuit The fourth port of is connected to the first port of the first capacitor, the drain of the first transistor, and the drain of the third transistor.

In an embodiment of the present application, the second sub-input circuit includes a third capacitor, a fourth capacitor, a fifth transistor, a sixth transistor, a seventh transistor, an eighth transistor, and a second inductor, wherein:

The first port of the third capacitor is connected to the drain of the fifth transistor and the drain of the seventh transistor, the source of the fifth transistor is connected to the drain of the sixth transistor, and the The source of the seventh transistor is connected to the drain of the eighth transistor and the first port of the fourth capacitor, the second port of the fourth capacitor is connected to the first port of the second inductor, and the The first port of the second sub-input circuit is connected to the second port of the second inductor, and the second port of the second sub-input circuit is connected to the source of the fifth transistor and the drain of the sixth transistor Connected, the third port of the second sub-input circuit is connected to the second port of the third capacitor, the source of the sixth transistor, and the source of the eighth transistor, the second sub-input circuit The fourth port of is connected to the first port of the third capacitor, the drain of the fifth transistor, and the drain of the seventh transistor.

In an embodiment of the present application, the first port of the first primary winding is connected to the first port of the first sub-input circuit, and the second port of the first primary winding is connected to the first port of the first sub-input circuit. The second port of the sub-input circuit is connected.

In an embodiment of the present application, the first port of the second primary winding is connected to the first port of the second sub-input circuit, and the second port of the second primary winding is connected to the second port of the second primary winding. The second port of the input circuit is connected.

In an embodiment of the present application, the output circuit includes: a first switch unit, a second switch unit and a fifth capacitor, wherein:

The first port of the fifth capacitor is connected to the first port of the second switch unit and the first port of the first switch unit.

In an embodiment of the present application, the first port of the secondary winding is connected to the second port of the second switch unit, and the second port of the secondary winding is connected to the second port of the fifth inductor Connected, the third port of the secondary winding is connected to the second port of the first switch unit.

In an embodiment of the present application, the first switch unit and the second switch unit include at least one of the following: a rectifier diode and a field effect transistor.

The second aspect of the embodiments of the present application provides a switching power supply, including the voltage conversion circuit of the integrated vehicle charger disclosed in the first aspect of the embodiments of the present application.

A third aspect of the present invention provides a vehicle-mounted device, including the voltage conversion circuit of the integrated vehicle-mounted charger disclosed in the first aspect of the embodiments of the present application and the switching power supply disclosed in the second aspect.

In the embodiment of this application, the input circuit is connected to the transformer, the transformer is connected to the output circuit, the first sub-input circuit is connected in series with the second sub-input circuit, and the first sub-input circuit is connected to the first port and the second port of the first primary winding. The second sub-input circuit is connected to the first port and the second port of the second primary winding, and the secondary winding is connected to the output circuit; the high voltage signal passes through the first sub-input circuit and the second sub-input The circuit respectively generates a first electrical signal and a second electrical signal. The first electrical signal passes through the first primary winding of the transformer to generate a first magnetic flux, and the second electrical signal passes through the second primary winding of the transformer. A second magnetic flux is generated, the direction of the first magnetic flux is the same as the direction of the second magnetic flux, the first magnetic flux and the second magnetic flux are superimposed by the secondary winding of the transformer to generate an induced electromotive force, the The induced electromotive force generates a low voltage signal through the output circuit. Compared with an LLC resonant circuit, the embodiment of the present application consists of two LLC resonant circuits in series to form two working branches. The two LLC resonant circuits carry the input voltage at the same time, and the voltage remains the same, thereby improving the circuit Adaptation range of the input voltage.

These and other aspects of the application will be more concise and understandable in the description of the following embodiments.

Description of the drawings

In order to more clearly describe the technical solutions in the embodiments of the present invention, the following will briefly introduce the accompanying drawings used in the description of the embodiments. Obviously, the accompanying drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative work, other drawings can be obtained based on these drawings.

Fig. 1 is a schematic structural diagram of a common half-bridge LLC resonant circuit in the prior art;

Fig. 2 is a schematic structural diagram of a common full-bridge LLC resonant circuit in the prior art;

3 is a circuit block diagram of a voltage conversion circuit of an integrated vehicle charger provided by an embodiment of the present application;

4A is a schematic structural diagram of a voltage conversion circuit for an integrated vehicle charger provided by an embodiment of the present application;

4B is a schematic diagram of a first current direction provided by an embodiment of the present application;

4C is a schematic diagram of a second current direction provided by an embodiment of the present application;

4D is a schematic diagram of a third current direction provided by an embodiment of the present application;

4E is a schematic diagram of a fourth current direction provided by an embodiment of the present application;

FIG. 5 is a schematic structural diagram of the first input circuit shown in FIG. 4A;

FIG. 6 is a schematic structural diagram of the second input circuit shown in FIG. 4A;

FIG. 7 is a schematic diagram of the structure of the output circuit shown in FIG. 4A;

Fig. 8 is a schematic structural diagram of the transformer shown in Fig. 4A.

Detailed ways

In order to enable those skilled in the art to better understand the solution of the application, the technical solutions in the embodiments of the application will be clearly and completely described below in conjunction with the drawings in the embodiments of the application. Obviously, the described embodiments are only It is a part of the embodiments of this application, not all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative work should fall within the protection scope of this application.

Detailed descriptions are given below.

The terms "first", "second", "third" and "fourth" in the description and claims of the application and the drawings are used to distinguish different objects, rather than describing a specific order . In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes unlisted steps or units, or optionally also includes Other steps or units inherent to these processes, methods, products or equipment.

Reference to "embodiments" herein means that a specific feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art clearly and implicitly understand that the embodiments described herein can be combined with other embodiments.

Hereinafter, some terms in this application are explained to facilitate the understanding of those skilled in the art.

In the prior art, there are mainly two common LLC resonant circuits in the voltage conversion circuit of the integrated vehicle charger: a half-bridge LLC resonant circuit and a full-bridge LLC resonant circuit.

Refer to FIG. 1, which is a common half-bridge LLC resonant circuit in the prior art. The figure includes the power supply, two field effects (Q1 and Q2), the primary input filter capacitor C1, the transformer T1, the primary LLC resonant circuit, and the output circuit. The transformer T1 includes a primary winding, a first secondary winding, and a second secondary winding. The primary-side LLC resonant circuit includes a series-connected resonant capacitor C2, a resonant inductor L1, and the magnetic inductance of the primary winding itself. The output circuit includes the magnetic induction of the first secondary winding and the second secondary winding itself, rectifier diodes (D1 and D2), and the secondary output capacitor C3.

Refer to FIG. 2, which is a common full-bridge LLC resonant circuit in the prior art. The figure includes the power supply, four field effects (Q1, Q2, Q3 and Q4), the primary input filter capacitor C1, the transformer T1, the primary LLC resonant circuit, and the output circuit. The transformer T1 includes a primary winding, a first secondary winding, and a second secondary winding. The primary-side LLC resonant circuit includes a series-connected resonant capacitor C2, a resonant inductor L1, and the magnetic inductance of the primary winding itself. The output circuit includes the magnetic induction of the first secondary winding and the second secondary winding itself, rectifier diodes (D1 and D2), and the secondary output capacitor C3.

However, whether it is a half-bridge LLC resonant circuit or a full-bridge LLC resonant circuit, there is such a problem that an LLC resonant circuit cannot meet the higher and higher input voltage requirements of the vehicle power supply for the circuit. In the embodiment of the present application, the first sub-input circuit and the second sub-input circuit jointly carry a higher input voltage, so the adapting range of the input voltage of the circuit can be increased.

Please refer to FIG. 3, which is a circuit block diagram of a voltage conversion circuit of an integrated vehicle charger provided by an embodiment of the present application. The voltage conversion circuit of the integrated vehicle charger includes an input circuit, a transformer, and an output circuit. The input circuit includes a first A sub-input circuit, a second sub-input circuit, and the transformer includes a first primary winding, a second primary winding and a secondary winding wound on a magnetic core, wherein:

The input circuit is connected to the transformer, the transformer is connected to the output circuit, the first sub-input circuit is connected in series with the second sub-input circuit, the first sub-input circuit is connected to the first port and the second port of the first primary winding, and the second sub-input The circuit is connected to the first port and the second port of the second primary winding, and the secondary winding is connected to the output circuit;

The high voltage signal passes through the first sub-input circuit and the second sub-input circuit to generate the first electrical signal and the second electrical signal respectively. The first electrical signal passes through the first primary winding of the transformer to generate the first magnetic flux, and the second electrical signal passes through the transformer. The second primary winding generates a second magnetic flux. The direction of the first magnetic flux is the same as the direction of the second magnetic flux. The first magnetic flux and the second magnetic flux are superimposed through the secondary winding of the transformer to generate an induced electromotive force. The induced electromotive force generates a low voltage through the output circuit signal.

It can be seen that, compared to an LLC resonant circuit carrying the input voltage, the first sub-input circuit and the second sub-input circuit jointly carry a higher input voltage in the embodiment of the present application, so the input voltage of the circuit can be improved.配Scope.

Please refer to FIG. 4A, which is a schematic structural diagram of a voltage conversion circuit of an integrated vehicle charger provided by an embodiment of the present application. The voltage conversion circuit of the integrated vehicle charger includes an input circuit 100, an output circuit 200, and a transformer 300. The circuit 100 includes a first sub-input circuit 110 and a second sub-input circuit 120, wherein:

The first sub-input circuit 110 includes a first capacitor C1, a second capacitor C2, a first transistor Q1, a second transistor Q2, a third transistor Q3, a fourth transistor Q4 and a first inductor L1, and a first port of the first capacitor C1 Connected to the drain of the first transistor Q1 and the drain of the third transistor Q3, the source of the first transistor Q1 is connected to the drain of the second transistor Q2, and the source of the third transistor Q3 is connected to the drain of the fourth transistor Q4 And the first port of the second capacitor C2, the second port of the second capacitor C2 is connected to the first port of the first inductor L1, the first port 111 of the first sub-input circuit 110 is connected to the second port of the first inductor L1 The second port 112 of the first sub-input circuit 110 is connected to the source of the first transistor Q1 and the drain of the second transistor Q2. The third port 113 of the first sub-input circuit 110 is connected to the second capacitor C1. Port, the source of the second transistor Q2 and the source of the fourth transistor Q4 are connected, the fourth port 114 of the first sub-input circuit 110 is connected to the first port of the first capacitor C1, the drain of the first transistor Q1 and the third The drain of the transistor Q3 is connected.

The second sub-input circuit 120 includes a third capacitor C3, a fourth capacitor C4, a fifth transistor Q5, a sixth transistor Q6, a seventh transistor Q7, an eighth transistor Q8, a second inductor L2, and a first port of the third capacitor C3 Connected to the drain of the fifth transistor Q5 and the drain of the seventh transistor Q7, the source of the fifth transistor Q5 is connected to the drain of the sixth transistor Q6, and the source of the seventh transistor Q7 is connected to the drain of the eighth transistor Q8 And the first port of the fourth capacitor C4, the second port of the fourth capacitor C4 is connected to the first port of the second inductor L2, the first port 121 of the second sub-input circuit 120 is connected to the second port of the second inductor L2 The second port 122 of the second sub-input circuit 120 is connected to the source of the fifth transistor Q5 and the drain of the sixth transistor Q6. The third port 123 of the second sub-input circuit 120 is connected to the second terminal of the third capacitor C3. Port, the source of the sixth transistor Q6 and the source of the eighth transistor Q8 are connected, the fourth port 124 of the second sub-input circuit 120 and the first port of the third capacitor C3, the drain of the fifth transistor Q5 and the seventh The drain of the transistor Q7 is connected.

Among them, the first transistor Q1, the second transistor Q2, the third transistor Q3, the fourth transistor Q4, the fifth transistor Q5, the sixth transistor Q6, the seventh transistor Q7, and the eighth transistor Q8 are all field effect transistors.

The third port 113 of the first sub-input circuit 110 is connected to the fourth port 124 of the second sub-input circuit 120, the fourth port 114 of the first sub-input circuit 110 is connected to the anode of the input source, and the second sub-input circuit 120 The third port 123 is connected to the negative electrode of the input source.

Among them, the second transistor Q2, the third transistor Q3, the sixth transistor Q6 and the seventh transistor Q7 switch synchronously, and the first transistor Q1, the fourth transistor Q4, the fifth transistor Q5 and the eighth transistor Q8 switch synchronously. When the second transistor Q2, the third transistor Q3, the sixth transistor Q6 and the seventh transistor Q7 are turned on synchronously, and the first transistor Q1, the fourth transistor Q4, the fifth transistor Q5 and the eighth transistor Q8 are turned off synchronously, the The direction of the first magnetic flux generated by an electrical signal passing through the first primary winding of the transformer is horizontal to the left, and the direction of the second magnetic flux generated by the second electrical signal passing through the second primary winding of the transformer is horizontal to the left. When the transistor Q1, the fourth transistor Q4, the fifth transistor Q5 and the eighth transistor Q8 are turned on synchronously, and the second transistor Q2, the third transistor Q3, the sixth transistor Q6 and the seventh transistor Q7 are turned off synchronously, the first electrical signal The direction of the first magnetic flux generated by the first primary winding of the transformer is horizontal to the right, and the direction of the second magnetic flux generated by the second electrical signal through the second primary winding of the transformer is horizontal to the right.

The first sub-input circuit 110 and the second sub-input circuit 120 jointly carry the input high voltage. The high-voltage signal passes through the first sub-input circuit 110 to generate a first electrical signal, and the high-voltage signal passes through the second sub-input circuit 120 to generate a first electrical signal. Two electrical signals. The first electrical signal passes through the first primary winding of the transformer to generate a first magnetic flux, and the second electrical signal passes through the second primary winding of the transformer to generate a second magnetic flux. The direction of the first magnetic flux is the same as the direction of the second magnetic flux. , The first magnetic flux and the second magnetic flux are superimposed through the secondary winding of the transformer to generate an induced electromotive force, and the induced electromotive force passes through the output circuit 200 to generate a low voltage signal. Wherein, the first port 301 of the first primary winding is connected to the first port 111 of the first sub-input circuit 110, and the second port 302 of the first primary winding is connected to the second port 112 of the first sub-input circuit 110, The third port 303 of the first primary winding is connected to the first port 121 of the second sub-input circuit 120, the fourth port 304 of the first primary winding is connected to the second port 122 of the second sub-input circuit 120, and the secondary side The first port 305 of the winding is connected to the cathode of the second rectifier diode D2, the second port 306 of the secondary winding is connected to the second port of the fifth capacitor C5, and the third port 307 of the secondary winding is connected to the first rectifier diode D1. Negative connection.

The output circuit 200 includes a first rectifier diode D1, a second rectifier diode D2, and a fifth capacitor C5. The first port of the fifth capacitor C5 is connected to the anode of the second rectifier diode D1 and the anode of the first rectifier diode D2.

Among them, the first rectifier diode D1 and the second rectifier diode D2 can be replaced by field effect transistors.

Among them, the first primary winding, the second primary winding and the secondary winding are wound on a magnetic core, and the windings are connected in series through the magnetic pole layer and the transformer compound mode.

It can be seen that, compared to an LLC resonant circuit, the embodiment of the present application consists of two full-bridge LLC resonant circuits in series to form two working branches. The two full-bridge LLC resonant circuits simultaneously carry the input voltage, and The voltage remains the same, which can increase the adaptation range of the circuit's input voltage.

The working flow of the integrated on-board charger as shown in FIG. 4A is described in detail below.

First, it should be noted that since the first sub-input circuit 110 and the second sub-input circuit 120 have the same structure, the internal component parameters of the two are also the same. For example, the capacitance values of the first capacitor C1 and the third capacitor C3 are the same, and the other components should be understood in the same way, and will not be repeated here. Secondly, in the input circuit 100, the first transistor Q1, the fourth transistor Q4, the fifth transistor Q5 and the eighth transistor Q8 are turned on or off synchronously, and the second transistor Q2, the third transistor Q3, the sixth transistor Q6 and the The seven transistors Q7 are turned on or off synchronously. In other words, the gate of the first transistor Q1, the gate of the fourth transistor Q4, the gate of the fifth transistor Q5, and the gate of the eighth transistor Q8 are connected to the same signal. The gates of the three transistors Q3, the sixth transistor Q6, and the gate of the seventh transistor Q7 are connected to the same signal. In addition, the first sub-input circuit 110 and the second sub-input circuit 120 are connected in series, so that both have the same voltage division for the input signal.

Further, the working process of the voltage conversion circuit of the integrated on-board charger includes four stages in one cycle, as follows:

The first stage: the second transistor Q2, the third transistor Q3, the sixth transistor Q6, and the seventh transistor Q7 are turned on, and the first transistor Q1, the fourth transistor Q4, the fifth transistor Q5, and the eighth transistor Q8 are turned off status.

In the first stage, the current direction in the voltage conversion circuit of the integrated on-board charger is shown in Figure 4B. The first capacitor C1, the second transistor Q2, the third transistor Q3, the second capacitor C2, and the first inductor L1 form a first resonant circuit, and the first electrical signal in the first resonant circuit first rises and then falls in a sinusoidal function; third The capacitor C3, the sixth transistor Q6, the seventh transistor Q7, the fourth capacitor C4, and the second inductor L2 form a second resonant circuit. The second electrical signal in the second resonant circuit rises first and then falls as a sinusoidal function; the first resonant circuit The first electrical signal in the transformer generates a first magnetic flux through the first primary winding of the transformer, and the second electrical signal in the second resonant circuit generates a second magnetic flux through the second primary winding of the transformer. The direction of the first magnetic flux is the same as that of the second The direction of the magnetic flux is the same. The first magnetic flux passes through the secondary winding of the transformer to generate the first induced electromotive force, and the second magnetic flux passes through the secondary winding of the transformer to generate the second induced electromotive force. Because the first primary winding and the second primary winding are wound in On the same magnetic core and well coupled with each other, the first induced electromotive force and the second induced electromotive force generated are the same in magnitude, and the directions are both positive and negative. The induced electromotive force generated at the sixth port 306 and the seventh port 307 of the secondary winding of the transformer turns on the first rectifier diode D1 to supply power to the fifth capacitor C5 and the output load, and the electrical signal first rises and then falls in a sinusoidal function.

The second stage: the second transistor Q2, the third transistor Q3, the sixth transistor Q6 and the seventh transistor Q7 are in the off state, and the first transistor Q1, the fourth transistor Q4, the fifth transistor Q5 and the eighth transistor Q8 are in the on state status.

In the second stage, the current direction in the voltage conversion circuit of the integrated on-board charger is shown in Figure 4C. The first electrical signal flowing through the second transistor Q2 and the third transistor Q3 and the second electrical signal flowing through the sixth transistor Q6 and the seventh transistor Q7 are in sinusoidal waveforms, first rising and then falling; when flowing through the second transistor Q2 When the first electrical signal of the third transistor Q3 and the second electrical signal flowing through the sixth transistor Q6 and the seventh transistor Q7 drop to zero, the second transistor Q2, the third transistor Q3, the sixth transistor Q6, and the seventh transistor Q6 Transistor Q7 achieves zero current shutdown. After the second transistor Q2, the third transistor Q3, the sixth transistor Q6, and the seventh transistor Q7 are turned off, the first electrical signal flows through the first transistor Q1 because the first electrical signal and the second electrical signal still maintain the original flow direction. And the fourth transistor Q4, the second electrical signal flows through the fifth transistor Q5 and the eighth transistor Q8, so that the voltage drop of the first transistor Q1, the fourth transistor Q4, the fifth transistor Q5 and the eighth transistor Q8 is zero, the first The transistor Q1, the fourth transistor Q4, the fifth transistor Q5, and the eighth transistor Q8 realize zero voltage turn-on. At this time, the directions of the induced electromotive force generated by the first primary winding, the second primary winding, and the secondary winding are up-negative and down-positive. The induced electromotive force generated at the fifth port 305 and the sixth port 306 of the secondary winding of the transformer The second rectifier diode D2 is turned on to supply power to the fifth capacitor C5 and the output load.

The third stage: the second transistor Q2, the third transistor Q3, the sixth transistor Q6 and the seventh transistor Q7 are in the off state, the first transistor Q1, the fourth transistor Q4, the fifth transistor Q5 and the eighth transistor Q8 are in the on state status.

In the third stage, the current direction in the voltage conversion circuit of the integrated on-board charger is shown in Figure 4D. After the first electrical signal flowing through the first transistor Q1 and the fourth transistor Q4 and the second electrical signal of the fifth transistor Q5 and the eighth transistor Q8 have reversed zero crossings, the first transistor Q1, the fourth transistor Q4, and the fifth transistor Q5 and the eighth transistor Q8 are in a conducting state. The first capacitor C1, the first transistor Q1, the fourth transistor Q4, the second capacitor C2, and the first inductor L1 form a third resonant circuit, and the third electrical signal in the third resonant circuit first rises and then falls in a sinusoidal function; third The capacitor C3, the fifth transistor Q5, the eighth transistor Q8, the fourth capacitor C4 and the second inductor L2 form a fourth resonant circuit. The fourth electrical signal in the fourth resonant circuit first rises and then falls as a sine function; the third resonant circuit The third electrical signal in the transformer generates a third magnetic flux through the first primary winding of the transformer, and the fourth electrical signal in the fourth resonant circuit generates a fourth magnetic flux through the second primary winding of the transformer. The direction of the third magnetic flux is the same as that of the fourth The direction of the magnetic flux is the same. The third magnetic flux passes through the secondary winding of the transformer to generate a third induced electromotive force, and the fourth magnetic flux passes through the secondary winding of the transformer to generate a fourth induced electromotive force. Because the first primary winding and the second primary winding are wound in They are on the same magnetic core and are well coupled to each other, so the third induced electromotive force and the fourth induced electromotive force generated have the same magnitude, and the directions are both up and down. The induced electromotive force generated at the fifth port 305 and the sixth port 306 of the secondary winding of the transformer turns on the second rectifier diode D2 to supply power to the fifth capacitor C5 and the output load, and the electrical signal first rises and then falls in a sinusoidal function.

Fourth stage: the second transistor Q2, the third transistor Q3, the sixth transistor Q6, and the seventh transistor Q7 are in the on state, and the first transistor Q1, the fourth transistor Q4, the fifth transistor Q5 and the eighth transistor Q8 are in the off state status.

In the fourth stage, the current direction in the voltage conversion circuit of the integrated on-board charger is shown in Figure 4E. The third electrical signal flowing through the first transistor Q1 and the fourth transistor Q4 and the fourth electrical signal flowing through the fifth transistor Q5 and the eighth transistor Q8 all have sinusoidal waveforms, which rise first and then fall; when flowing through the first transistor Q1 When the third electrical signal of the fourth transistor Q4 and the fourth electrical signal flowing through the fifth transistor Q5 and the eighth transistor Q8 drop to zero, the first transistor Q1, the fourth transistor Q4, the fifth transistor Q5, and the eighth transistor Q8 Transistor Q8 achieves zero current shutdown. After the first transistor Q1, the fourth transistor Q4, the fifth transistor Q5, and the eighth transistor Q8 are turned off, since the third electrical signal and the fourth electrical signal still maintain the original flow direction, the third electrical signal flows through the second transistor Q2 And the third transistor Q3, the fourth electrical signal flows through the sixth transistor Q6 and the seventh transistor Q7, so that the voltage drop of the second transistor Q2, the third transistor Q3, the sixth transistor Q6 and the seventh transistor Q7 is zero, the second The transistor Q2, the third transistor Q3, the sixth transistor Q6, and the seventh transistor Q7 realize zero voltage turn-on. At this time, the direction of the induced electromotive force generated by the first primary winding, the second primary winding and the secondary winding is positive and negative, and the induced electromotive force generated at the sixth port 306 and the seventh port 307 of the secondary winding of the transformer The first rectifier diode D1 is turned on to supply power to the fifth capacitor C5 and the output load.

Please refer to FIG. 5. FIG. 5 is a schematic structural diagram of the first sub-input circuit 110 in the voltage conversion circuit of the integrated vehicle charger shown in FIG. 4A, in which:

Among them, the first transistor Q1, the second transistor Q2, the third transistor Q3, and the fourth transistor Q4 are all field effect transistors.

Please refer to FIG. 6. FIG. 6 is a schematic structural diagram of the second sub-input circuit 120 in the voltage conversion circuit of the integrated vehicle charger shown in FIG. 4A, in which:

Among them, the fifth transistor Q5, the sixth transistor Q6, the seventh transistor Q7, and the eighth transistor Q8 are all field effect transistors.

Please refer to FIG. 7, which is a schematic structural diagram of the output circuit shown in FIG. 4A. The output circuit 200 includes a first rectifier diode D1, a second rectifier diode D2, and a fifth capacitor C5. The first port of the fifth capacitor C5 It is connected to the anode of the second rectifier diode D1 and the anode of the first rectifier diode D2.

Please refer to FIG. 8. FIG. 8 is a schematic structural diagram of a transformer shown in FIG. 4A. The transformer 300 includes a first port 301 of a first primary winding, a second port 302 of the first primary winding, and a second original winding. The third port 303 of the side winding, the second port 304 of the second primary winding, the first port 305 of the secondary winding, the second port 306 of the secondary winding, and the third port 307 of the secondary winding.

In a possible example, the first port 301 of the first primary winding is connected to the first port 111 of the first sub-input circuit 110, and the second port 302 of the first primary winding is connected to the first port 111 of the first sub-input circuit 110. Two ports 112 are connected, the third port 303 of the first primary winding is connected to the first port 121 of the second sub-input circuit 120, and the fourth port 304 of the first primary winding is connected to the second port of the second sub-input circuit 120 122 is connected, the first port 305 of the secondary winding is connected to the negative electrode of the second rectifier diode D2, the second port 306 of the secondary winding is connected to the second port of the fifth capacitor C5, and the third port 307 of the secondary winding is connected to the The cathode of a rectifier diode D1 is connected.

In a possible example, an embodiment of the present application provides a switching power supply, and the switching power supply includes the voltage conversion circuit of an integrated vehicle charger provided in any of the above application embodiments.

Wherein, the voltage conversion circuit of the integrated on-board charger in the switching power supply is the same as the voltage conversion circuit of the integrated on-board charger described in any of the above application embodiments, and will not be described here.

In a possible example, an embodiment of the present application provides a vehicle-mounted device, and the vehicle-mounted device includes the voltage conversion circuit of an integrated vehicle charger provided in any of the foregoing application embodiments or the switching power supply provided in the foregoing application embodiments.

Wherein, the voltage conversion circuit of the integrated on-board charger in the on-board equipment is the same as the voltage conversion circuit of the integrated on-board charger described in any of the above application embodiments, and will not be described here.

It should be noted that for the foregoing application embodiments, for the sake of simple description, they are all expressed as a series of action combinations, but those skilled in the art should know that this application is not limited by the described sequence of actions. Because according to this application, some steps can be performed in other order or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by this application.

In the above-mentioned embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in an embodiment, reference may be made to related descriptions of other embodiments.

In the several embodiments provided in this application, it should be understood that the disclosed device may be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of the above-mentioned units is only a logical function division, and there may be other divisions in actual implementation, for example, multiple units or components can be combined or integrated. To another system, or some features can be ignored, or not implemented. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection through some interfaces, devices or units, and may be in electrical or other forms.

The units described above as separate components may or may not be physically separate, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the objectives of the solutions of the embodiments.

In addition, the functional units in each embodiment of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units may be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or software functional unit.

The embodiments of the application are described in detail above, and specific examples are used in this article to illustrate the principles and implementation of the application. The descriptions of the above embodiments are only used to help understand the application and its core ideas; at the same time, for the field According to the ideas of the application, the general technical personnel of, will have changes in the specific implementation and the scope of application. In summary, the content of this specification should not be construed as a limitation of the application.

Claims

A voltage conversion circuit for an integrated vehicle charger, which is characterized by comprising an input circuit, a transformer, and an output circuit. The input circuit includes a first sub-input circuit and a second sub-input circuit. The transformer includes a first primary winding. , The second primary winding and secondary winding, of which:

The input circuit is connected to the transformer, the transformer is connected to the output circuit, the first sub-input circuit is connected in series with the second sub-input circuit, and the first sub-input circuit is connected to the first original circuit. The first port and the second port of the side winding are connected, the second sub-input circuit is connected with the first port and the second port of the second primary winding, and the secondary winding is connected with the output circuit;

The high voltage signal passes through the first sub-input circuit and the second sub-input circuit to generate a first electrical signal and a second electrical signal, respectively, and the first electrical signal passes through the first primary winding of the transformer to generate a first electrical signal. Magnetic flux, the second electrical signal passes through the second primary winding of the transformer to generate a second magnetic flux, the direction of the first magnetic flux is the same as the direction of the second magnetic flux, the first magnetic flux and the second magnetic flux The magnetic flux superimposes through the secondary winding of the transformer to generate an induced electromotive force, and the induced electromotive force generates a low voltage signal through the output circuit.
The voltage conversion circuit of an integrated vehicle charger according to claim 1, wherein the first sub-input circuit includes a first capacitor, a second capacitor, a first transistor, a second transistor, a third transistor, and a fourth Transistor and first inductor, where:

The first port of the first capacitor is connected to the drain of the first transistor and the drain of the third transistor, the source of the first transistor is connected to the drain of the second transistor, and the The source of the third transistor is connected to the drain of the fourth transistor and the first port of the second capacitor, the second port of the second capacitor is connected to the first port of the first inductor, and the The first port of the first sub-input circuit is connected to the second port of the first inductor, and the second port of the first sub-input circuit is connected to the source of the first transistor and the drain of the second transistor Connected, the third port of the first sub-input circuit is connected to the second port of the first capacitor, the source of the second transistor and the source of the fourth transistor, the first sub-input circuit The fourth port of is connected to the first port of the first capacitor, the drain of the first transistor, and the drain of the third transistor.
The voltage conversion circuit of an integrated vehicle charger according to claim 1 or 2, wherein the second sub-input circuit includes a third capacitor, a fourth capacitor, a fifth transistor, a sixth transistor, a seventh transistor, The eighth transistor and the second inductor, where:

The first port of the third capacitor is connected to the drain of the fifth transistor and the drain of the seventh transistor, the source of the fifth transistor is connected to the drain of the sixth transistor, and the The source of the seventh transistor is connected to the drain of the eighth transistor and the first port of the fourth capacitor, the second port of the fourth capacitor is connected to the first port of the second inductor, and the The first port of the second sub-input circuit is connected to the second port of the second inductor, and the second port of the second sub-input circuit is connected to the source of the fifth transistor and the drain of the sixth transistor Connected, the third port of the second sub-input circuit is connected to the second port of the third capacitor, the source of the sixth transistor, and the source of the eighth transistor, the second sub-input circuit The fourth port of is connected to the first port of the third capacitor, the drain of the fifth transistor, and the drain of the seventh transistor.
The voltage conversion circuit of the integrated vehicle charger according to claim 3, the first port of the first primary winding is connected to the first port of the first sub-input circuit, and the first port of the first primary winding The second port is connected to the second port of the first sub-input circuit.
The voltage conversion circuit of the integrated vehicle charger of claim 4, wherein the first port of the second primary winding is connected to the first port of the second sub-input circuit, and the first port of the second primary winding is The second port is connected to the second port of the second input circuit.
The voltage conversion circuit of an integrated vehicle charger according to any one of claims 1-5, wherein the output circuit comprises: a first switch unit, a second switch unit and a fifth capacitor, wherein:

The first port of the fifth capacitor is connected to the first port of the second switch unit and the first port of the first switch unit.
The voltage conversion circuit of the integrated vehicle charger of claim 6, wherein the first port of the secondary winding is connected to the second port of the second switch unit, and the second port of the secondary winding is The port is connected to the second port of the fifth inductor, and the third port of the secondary winding is connected to the second port of the first switch unit.
The voltage conversion circuit of the integrated vehicle charger according to claim 6 or 7, wherein the first switch unit and the second switch unit comprise at least one of the following: a rectifier diode and a field effect transistor.
A switching power supply, characterized in that the switching power supply comprises the voltage conversion circuit of the integrated vehicle charger according to any one of claims 1-8.
A vehicle-mounted device, characterized in that, the vehicle-mounted device comprises the voltage conversion circuit of the integrated vehicle charger or a switching power supply according to any one of claims 1-9.