An equivalent full-bridge rectifier circuit

Abstract

The present invention discloses an equivalent full-bridge rectifier circuit, comprising: a first switch element, a second switch element, a third switch element, a fourth switch element, a transformer, an output positive electrode and an output negative electrode; wherein the transformer comprises a first secondary winding and a second secondary winding; the first secondary winding, the first switch element and the fourth switch element form a first rectifier circuit under the condition of an AC input positive polarity voltage, and the second secondary winding, the second switch element and the third switch element form a second rectifier circuit under the condition of an AC input negative polarity voltage. In the present invention, the secondary full-bridge switch rectifier device is divided into two independent circuits by splitting the secondary winding, so that the power circuit of the secondary rectification becomes a simple series circuit, and the secondary windings of the transformer are respectively connected to the independent switch rectifier devices, and no additional branches are required, which simplifies the wiring and layout difficulty of the PCB power device, and is conducive to improving the power density and reducing the loss.

Description

Technical Field

[0001] The invention relates to the technical field of power electronic circuits, in particular to an equivalent full-bridge rectifier circuit. Background Art

[0002] At present, relevant prior arts such as the full-bridge rectifier circuit involved in the prior patent application CN219227265U, which is composed of a transformer secondary winding and four switching rectifier devices, have been widely used in various power supply circuits. The biggest advantage of the full-bridge rectifier circuit is that the voltage stress platform of the switching rectifier device is equal to the output voltage platform; however, the full-bridge rectifier circuit has defects in PCB layout, which is mainly reflected in the relatively large number of power connection lines from the transformer secondary winding tap to the switching rectifier device. Each transformer winding must be connected to two switching rectifier devices, and each switching rectifier device must be connected to the rectifier output positive or negative through a power line; in addition, in actual application scenarios, the distance between the switching rectifier devices in the same bridge arm often needs to be kept short enough to solve the problem of increased voltage stress caused by line parasitic impedance or increased additional losses caused by line impedance. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art at least to a certain extent. To this end, the present invention proposes an equivalent full-bridge rectifier circuit with high power density and low loss.

[0004] The embodiment of the present invention provides an equivalent full-bridge rectifier circuit, comprising: a first switch element, a second switch element, a third switch element, a fourth switch element, a transformer, an output positive electrode and an output negative electrode;

[0005] Wherein, the transformer comprises a first secondary winding and a second secondary winding;

[0006] The same-name end of the first secondary winding is connected to the first end of the first switch element, the opposite-name end of the first secondary winding is connected to the second end of the fourth switch element, the second end of the first switch element is connected to the output positive electrode, and the first end of the fourth switch element is connected to the output negative electrode, so that the first secondary winding, the first switch element and the fourth switch element form a first rectification circuit when an AC input positive polarity voltage is applied;

[0007] The same-name end of the second secondary winding is connected to the second end of the third switching element, the opposite-name end of the second secondary winding is connected to the first end of the second switching element, the second end of the second switching element is connected to the output positive electrode, and the first end of the third switching element is connected to the output negative electrode, so that the second secondary winding, the second switching element and the third switching element form a second rectification circuit when an AC input negative polarity voltage is applied.

[0008] Optionally, in one embodiment of the present invention, the first switch element / the second switch element / the third switch element / the fourth switch element comprises:

[0009] diode; or,

[0010] A first bidirectional controllable switch device and a diode connected in parallel; or,

[0011] A second bidirectional controllable switch device, wherein the second bidirectional controllable switch device is parasitic with an anti-parallel diode.

[0012] Optionally, in one embodiment of the present invention, it further includes a first auxiliary switch element, a second auxiliary switch element, a third auxiliary switch element and a fourth auxiliary switch element;

[0013] The first end of the first auxiliary switch element is respectively connected to the same-name end of the second secondary winding and the second end of the third switch element, the second end of the first auxiliary switch element is connected to the output positive electrode, the first end of the fourth auxiliary switch element is connected to the output negative electrode, and the second end of the fourth auxiliary switch element is respectively connected to the opposite-name end of the second secondary winding and the first end of the second switch element, so that the second secondary winding, the first auxiliary switch element, the third switch element, the fourth auxiliary switch element and the second switch element form a third rectification loop when an AC input negative polarity voltage is applied;

[0014] The second end of the third auxiliary switching element is respectively connected to the same-name end of the first secondary winding and the first end of the first switching element, the first end of the third auxiliary switching element is connected to the output negative electrode, the second end of the second auxiliary switching element is connected to the output positive electrode, and the first end of the second auxiliary switching element is respectively connected to the opposite-name end of the first secondary winding and the second end of the fourth switching element, so that the first secondary winding, the first switching element, the third auxiliary switching element, the fourth switching element and the second auxiliary switching element form a fourth rectification circuit when an AC input positive polarity voltage is applied.

[0015] Optionally, in one embodiment of the present invention, the first auxiliary switch element / the second auxiliary switch element / the third auxiliary switch element / the fourth auxiliary switch element comprises:

[0016] diode; or,

[0017] at least two diodes connected in series; or,

[0018] A resistor and a diode connected in series.

[0019] Optionally, in one embodiment of the present invention, when the first switch element / the second switch element / the third switch element / the fourth switch element includes: a diode, or a first bidirectional controllable switch device and a diode connected in parallel, the first end of the first switch element / the second switch element / the third switch element / the fourth switch element is the positive electrode of the diode, and the second end of the first switch element / the second switch element / the third switch element / the fourth switch element is the negative electrode of the diode.

[0020] Optionally, in one embodiment of the present invention, the first bidirectional controllable switch device / the second bidirectional controllable switch device includes a MOSFET or an IGBT.

[0021] Compared with the full-bridge rectifier circuit in the related prior art, the equivalent full-bridge rectifier circuit proposed in the present invention has two secondary windings arranged on the transformer, and the secondary full-bridge switch rectifier device is divided into two independent circuits by splitting the secondary winding, that is, the first secondary winding, the first switch element and the fourth switch element form a first rectifier circuit under the condition of an AC input positive polarity voltage, and the second secondary winding, the second switch element and the third switch element form a second rectifier circuit under the condition of an AC input negative polarity voltage, so that the power circuit of the secondary rectification becomes a simple series circuit, and the secondary windings of the transformer are respectively connected to independent switch rectifier devices, without the need for additional branches, which simplifies the wiring and layout difficulty of PCB power devices, and is conducive to improving power density and reducing losses. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a circuit schematic diagram of an equivalent full-bridge rectifier circuit provided by an embodiment of the present invention;

[0023] Figure 2 It is a schematic diagram of a rectifier circuit corresponding to the equivalent full-bridge rectifier circuit provided by an embodiment of the present invention when the same-name end of the primary winding is input with a positive polarity voltage;

[0024] Figure 3 It is a schematic diagram of a rectifier circuit corresponding to the equivalent full-bridge rectifier circuit provided by an embodiment of the present invention when the same-name end of the primary winding is input with a negative polarity voltage;

[0025] Figure 4 It is a schematic diagram of a rectifier circuit corresponding to the equivalent full-bridge rectifier circuit provided by another embodiment of the present invention when the same-name end of the primary winding is a positive polarity voltage input;

[0026] Figure 5 It is a schematic diagram of a rectifier circuit corresponding to the equivalent full-bridge rectifier circuit provided by another embodiment of the present invention when the same-name end of the primary winding is input with a negative polarity voltage;

[0027] Figure 6 is a circuit schematic diagram of an equivalent full-bridge rectifier circuit provided by another embodiment of the present invention;

[0028] Figure 7 is a circuit schematic diagram of an equivalent full-bridge rectifier circuit provided by another embodiment of the present invention;

[0029] Figure 8 is a circuit schematic diagram of an equivalent full-bridge rectifier circuit provided by another embodiment of the present invention;

[0030] Fig. 9 It is a circuit schematic diagram of an equivalent full-bridge rectifier circuit provided by another embodiment of the present invention. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0032] It should be noted that, although the functional modules are divided in the device schematic, in some cases, the division may be performed in modules different from those in the device.

[0033] The present invention provides an equivalent full-bridge rectifier circuit, comprising: a first switch element, a second switch element, a third switch element, a fourth switch element, a transformer, an output positive electrode and an output negative electrode; wherein the transformer comprises a first secondary winding and a second secondary winding; the same-name end of the first secondary winding is connected to the first end of the first switch element, the opposite-name end of the first secondary winding is connected to the second end of the fourth switch element, the second end of the first switch element is connected to the output positive electrode, and the first end of the fourth switch element is connected to the output negative electrode, so that the first secondary winding, the first switch element and the fourth switch element form a first rectification loop under the condition of an alternating current input positive polarity voltage; the same-name end of the second secondary winding is connected to the second end of the third switch element, the opposite-name end of the second secondary winding is connected to the first end of the second switch element, the second end of the second switch element is connected to the output positive electrode, and the first end of the third switch element is connected to the output negative electrode, so that the second secondary winding, the second switch element and the third switch element form a second rectification loop under the condition of an alternating current input negative polarity voltage. In the present invention, the secondary full-bridge switch rectifier device is divided into two independent circuits by splitting the secondary winding, that is, the first secondary winding, the first switch element and the fourth switch element form a first rectifier circuit under the condition of an AC input positive polarity voltage, and the second secondary winding, the second switch element and the third switch element form a second rectifier circuit under the condition of an AC input negative polarity voltage, so that the power circuit of the secondary rectification becomes a simple series circuit, and the secondary windings of the transformer are respectively connected to independent switch rectifier devices without the need for additional branches, which simplifies the wiring and layout difficulty of PCB power devices, and is conducive to improving power density and reducing losses.

[0034] Figure 1 A circuit schematic diagram of an equivalent full-bridge rectifier circuit provided in one embodiment of the present invention.

[0035] like Figure 1 As shown, the equivalent full-bridge rectifier circuit specifically includes but is not limited to:

[0036] A first switch element D1, a second switch element D2, a third switch element D3, a fourth switch element D4, a transformer T, an output positive electrode P and an output negative electrode N;

[0037] The transformer T includes a first secondary winding T1 and a second secondary winding T2. The model and parameters of the transformer T can be set accordingly according to the specific application scenario, which is not limited here.

[0038] The same-name end of the first secondary winding T1 is connected to the first end of the first switch element D1, the opposite-name end of the first secondary winding T1 is connected to the second end of the fourth switch element D4, the second end of the first switch element D1 is connected to the output positive electrode P, and the first end of the fourth switch element D4 is connected to the output negative electrode N, so that the first secondary winding T1, the first switch element D1 and the fourth switch element D4 form a first rectification circuit when an AC positive polarity voltage is input;

[0039] The like-name end of the second secondary winding T2 is connected to the second end of the third switch element D3, the unlike-name end of the second secondary winding T2 is connected to the first end of the second switch element D2, the second end of the second switch element D2 is connected to the output positive pole P, and the first end of the third switch element D3 is connected to the output negative pole N, so that the second secondary winding T2, the second switch element D2 and the third switch element D3 form a second rectification circuit when an AC input negative polarity voltage is applied.

[0040] It can be seen that compared with the full-bridge rectifier circuit in the relevant prior art, the transformer T is provided with two secondary windings, and the secondary full-bridge switch rectifier device is divided into two independent loops by splitting the secondary winding, that is, the first secondary winding T1, the first switch element D1 and the fourth switch element D4 form a first rectifier loop under the condition of AC input positive polarity voltage, and the second secondary winding T2, the second switch element D2 and the third switch element D3 form a second rectifier loop under the condition of AC input negative polarity voltage, so that the power loop of the secondary rectification becomes a simple series loop, and the secondary windings of the transformer T are respectively connected to independent switch rectifier devices, without the need for additional branches, which simplifies the wiring and layout difficulty of PCB power devices, and is conducive to improving power density and reducing losses.

[0041] It should be noted that although Figure 1 The first switch element D1 / the second switch element D2 / the third switch element D3 / the fourth switch element D4 are all diodes, but this is only one implementation method of the embodiment of the present invention. In addition, the first switch element D1 / the second switch element D2 / the third switch element D3 / the fourth switch element D4 can also be but not limited to being a first bidirectional controllable switch device and a diode connected in parallel, or, all are second bidirectional controllable switch devices, wherein the second bidirectional controllable switch device is parasitic with an anti-parallel diode. This will be described in detail in the subsequent embodiments and will not be elaborated here.

[0042] In one embodiment, if Figure 1As shown, when the first switch element D1 / the second switch element D2 / the third switch element D3 / the fourth switch element D4 can be but not limited to being set as: a diode, the first end of the first switch element D1 / the second switch element D2 / the third switch element D3 / the fourth switch element D4 is the positive electrode of the diode, and the second end of the first switch element D1 / the second switch element D2 / the third switch element D3 / the fourth switch element D4 is the negative electrode of the diode. Such a setting can cooperate with the like-name end and the unlike-name end of each secondary winding to form a corresponding complete and reliable rectification circuit.

[0043] In order to better describe the basic working mode of the equivalent full-bridge rectifier circuit provided by the embodiment of the present invention, the specific principle is given below for detailed explanation.

[0044] Taking the first switch element D1 / the second switch element D2 / the third switch element D3 / the fourth switch element D4 as an example, if an alternating positive and negative polarity AC voltage is applied to the primary winding of the transformer T, then Figure 2 As shown, when the input voltage in the first stage is a positive polarity voltage, that is, the same-name end of the primary winding of the transformer T is positive and the opposite-name end is negative, then the voltage induced by the first secondary winding T1 of the transformer T is also positive at the same-name end and negative at the opposite-name end. At this time, the first secondary winding T1, the first switching element D1 and the fourth switching element D4 form a rectifier circuit, and the current starts from the same-name end of the first secondary winding T1, passes through the first switching element D1, the output positive electrode P, the output negative electrode N and the fourth switching element D4, and returns to the opposite-name end of the first secondary winding T1; and in the circuit composed of the second secondary winding T2, the second switching element D2, the third switching element D3, the output positive electrode P and the output negative electrode N, since the same-name end of the second secondary winding T2 is positive, the second switching element D2 and the third switching element D3 are in opposite polarity directions and are cut off, so no current path can be formed.

[0045] Similarly, if Figure 3 As shown, when the input voltage in the first stage is a negative polarity voltage, that is, the same-name end of the primary winding of the transformer T is negative and the opposite-name end is positive, then the voltage induced by the second secondary winding T2 of the transformer T is also negative at the same-name end and positive at the opposite-name end. At this time, the second secondary winding T2, the second switch element D2 and the third switch element D3 form a rectifier circuit, and the current starts from the opposite-name end of the second secondary winding T2, passes through the second switch element D2, the output positive electrode P, the output negative electrode N and the third switch element D3, and returns to the same-name end of the second secondary winding T2; and in the circuit composed of the first secondary winding T1, the first switch element D1, the fourth switch element D4, the output positive electrode P and the output negative electrode N, since the same-name end of the first secondary winding T1 is negative, the polarity directions of the first switch element D1 and the fourth switch element D4 are opposite and cut off, so no current path can be formed.

[0046] Please refer to Figure 4 and Figure 5 , Figure 4 The equivalent full-bridge rectifier circuit provided in one embodiment of the present invention corresponds to a rectifier circuit schematic diagram when the same-name end of the primary winding is a positive polarity voltage input. Figure 5 The equivalent full-bridge rectifier circuit provided in an embodiment of the present invention corresponds to a rectifier circuit schematic diagram when the same-name end of the primary winding is a negative polarity voltage input. It can be seen that compared with the full-bridge rectifier circuit in the related prior art, when the primary winding of the transformer T is respectively input with a positive polarity voltage, the rectifier circuit is looped through the first switch element D1 and the fourth switch element D4, and when the primary winding of the transformer T is respectively input with a negative polarity voltage, the rectifier circuit is looped through the second switch element D2 and the third switch element D3, and in either case, it can be realized. The present invention has a bipolar voltage rectification function, the only difference is that: the full-bridge rectifier circuit in the relevant prior art has only one secondary winding, and both rectification loops flow through the secondary winding, while the equivalent full-bridge rectifier circuit in the embodiment of the present invention has two secondary windings, and the two rectification loops are independent and flow through their respective secondary windings respectively. Since the functions of the circuits are the same, the primary winding current of the transformer T and the rectified output current waveforms of the switching element are exactly the same. Therefore, the current function of the equivalent full-bridge rectifier circuit in the embodiment of the present invention is equivalent to that of the full-bridge rectifier circuit in the relevant prior art.

[0047] In one embodiment, if Figure 6 As shown, the first switch element D1 / the second switch element D2 / the third switch element D3 / the fourth switch element D4 can be, but are not limited to, set as a combination element of a first bidirectional controllable switch device and a diode in parallel, wherein the first bidirectional controllable switch device can be, but are not limited to, a MOSFET or an IGBT; specifically, when the diode is turned on, the first bidirectional controllable switch device is turned on, and before the diode current is cut off, the first bidirectional controllable switch device is turned off; since the diode has a fixed voltage drop, when the first bidirectional controllable switch device is turned on when the diode is turned on, the current will be transferred from the diode to the first bidirectional controllable switch device, and due to the resistor The resistance is lower, thereby reducing the loss. Generally speaking, there is no parasitic reverse parallel diode inside the first bidirectional controllable switch device. Different from the first bidirectional controllable switch device, the second bidirectional controllable switch device itself will parasitize the reverse parallel diode. At this time, no additional separate parallel diode is required. The parasitic diode in the second bidirectional controllable switch device can replace the separate diode in the above embodiment. In other words, in this case, only a separate second bidirectional controllable switch device needs to be used as each switching element, which can save device cost to a certain extent. The second bidirectional controllable switch device can include but is not limited to MOSFET or IGBT.

[0048] In one embodiment, if Figure 6 As shown, when the first switch element D1 / the second switch element D2 / the third switch element D3 / the fourth switch element D4 are set as a combination element of a first bidirectional controllable switch device and a diode in parallel, the first end of the first switch element D1 / the second switch element D2 / the third switch element D3 / the fourth switch element D4 are all the positive electrodes of the diodes, and the second ends of the first switch element D1 / the second switch element D2 / the third switch element D3 / the fourth switch element D4 are all the negative electrodes of the diodes. Such a setting can cooperate with the like-name ends and the unlike-name ends of each secondary winding to form a corresponding complete and reliable rectification circuit.

[0049] Considering that one of the secondary windings of the transformer T in the aforementioned embodiment is conducting current, the other secondary winding is cut off. At this time, the two switching elements in the loop are connected in series and are both cut off. The sum of the voltage stresses borne by the two turned-off switching elements is twice the output positive and negative voltages. Since the two switching elements are connected in series and are both in the turned-off state, the voltage division of the two switching elements is uncertain at this time. Only when the parameters of the two switching elements are completely consistent can the voltage division be the same. However, since the parasitic parameters of each switching element are different, this is almost impossible in practice. As a result, there may be a situation where one switching element has more voltage division and the other has less voltage division. In extreme cases, one switching element may withstand the entire voltage, that is, twice the output positive and negative voltages. This obviously cannot form a voltage clamping effect and there is a certain risk of failure.

[0050] Based on this, the equivalent full-bridge rectifier circuit provided in the embodiment of the present invention is as follows: Figure 7 As shown, it can also include but is not limited to a first auxiliary switch element d11, a second auxiliary switch element d12, a third auxiliary switch element d13 and a fourth auxiliary switch element d14, wherein the first auxiliary switch element d11, the second auxiliary switch element d12, the third auxiliary switch element d13 and the fourth auxiliary switch element d14 are all diodes. In this case, the first end of the first auxiliary switch element d11 / the second auxiliary switch element d12 / the third auxiliary switch element d13 / the fourth auxiliary switch element d14 is the positive electrode of the diode, and the second end of the first auxiliary switch element d11 / the second auxiliary switch element d12 / the third auxiliary switch element d13 / the fourth auxiliary switch element d14 is the negative electrode of the diode. Such an arrangement can cooperate with the same-name end and the opposite-name end of each secondary winding to form a corresponding complete and reliable rectification circuit;

[0051] The first end of the first auxiliary switch element d11 is respectively connected to the same-name end of the second secondary winding T2 and the second end of the third switch element D3, the second end of the first auxiliary switch element d11 is connected to the output positive electrode P, the first end of the fourth auxiliary switch element d14 is connected to the output negative electrode N, and the second end of the fourth auxiliary switch element d14 is respectively connected to the opposite-name end of the second secondary winding T2 and the first end of the second switch element D2, so that the second secondary winding T2, the first auxiliary switch element d11, the third switch element D3, the fourth auxiliary switch element d14 and the second switch element D2 form a third rectification circuit when an AC input negative polarity voltage is applied;

[0052] The second end of the third auxiliary switch element d13 is respectively connected to the like-name end of the first secondary winding T1 and the first end of the first switch element D1, the first end of the third auxiliary switch element d13 is connected to the output negative pole N, the second end of the second auxiliary switch element d12 is connected to the output positive pole P, and the first end of the second auxiliary switch element d12 is respectively connected to the opposite-name end of the first secondary winding T1 and the second end of the fourth switch element D4, so that the first secondary winding T1, the first switch element D1, the third auxiliary switch element d13, the fourth switch element D4 and the second auxiliary switch element d12 form a fourth rectification circuit when an AC input positive polarity voltage is applied.

[0053] It can be seen that the first switch element D1, the second switch element D2, the third switch element D3 and the fourth switch element D4 are used as main circuit power devices, and the first auxiliary switch element d11, the second auxiliary switch element d12, the third auxiliary switch element d13 and the fourth auxiliary switch element d14 are used as auxiliary power devices; by adding auxiliary power devices, the rectifier circuit of each secondary winding becomes a complete full-bridge rectifier circuit, and therefore has the characteristics of voltage clamping of the full-bridge rectifier circuit. When the main circuit power device is not conducting, the circuit composed of the auxiliary power devices can be conducting. Therefore, each non-conducting main circuit power device is clamped to a fixed output positive and negative voltage, thereby keeping the voltage stress of the main circuit power device in the off state at a fixed value, that is, forming a voltage clamping effect, thereby preventing the main circuit power device from being subjected to high voltage stress and causing failure.

[0054] Specifically, when the first secondary winding T1 is turned on for rectification, the auxiliary power device corresponding to the second secondary winding T2 will actually be turned on for rectification. The auxiliary power device, as the name implies, is used to provide an auxiliary power circuit. It only provides a current path and does not want the rectified current to flow through. This is to avoid the current of the main power circuit from flowing into the auxiliary power circuit. However, as long as the device voltage stress of the shut-off main power circuit is higher than the output positive and negative voltages, the auxiliary power circuit where the corresponding auxiliary switch element is located will be forced to turn on, thereby clamping the voltage stress of the shut-off device to the output positive and negative voltages, thereby protecting the main circuit power device. Therefore, compared with the main circuit power device, the auxiliary switch element is usually a device with a smaller current specification, so it will not affect the layout and routing of the PCB. Even if the circuit is a full-bridge circuit, due to the different functions of each device, the auxiliary switch element is not in the main conduction loop, so the main power loop is still split through the secondary winding, and the full-bridge rectifier devices corresponding to each secondary winding are divided into two independent loops. The power loop of the secondary rectification becomes a simple series loop, and the transformer T windings are connected to independent power devices respectively, without the need for branching, which simplifies the PCB power wiring and layout difficulty, and is conducive to improving power density and reducing losses.

[0055] In one embodiment, if Figure 8 As shown, the first auxiliary switch element d11 / the second auxiliary switch element d12 / the third auxiliary switch element d13 / the fourth auxiliary switch element d14 can be but not limited to using multiple diodes connected in series. Due to the multiple diodes connected in series, the overall voltage drop becomes higher, that is, higher than the voltage drop of the main power circuit. Therefore, the current will only flow in the low voltage drop circuit, and the auxiliary power circuit will not be conductive due to the high voltage drop. Among them, the number and parameters of the diodes can be set accordingly according to the specific application scenario, and there is no restriction here.

[0056] In one embodiment, if Fig. 9 As shown, the first auxiliary switch element d11 / the second auxiliary switch element d12 / the third auxiliary switch element d13 / the fourth auxiliary switch element d14 can be but not limited to resistors and diodes connected in series. Since the impedance of the circuit connected in series in the auxiliary power loop becomes higher, and the current only flows in the loop with low impedance, the auxiliary power loop is not conductive due to the large impedance. The number and parameters of the resistors can be set accordingly according to the specific application scenario. For example, it can be but not limited to setting multiple resistors in series, which is equivalent to one resistor, etc., and there is no restriction here.

[0057] It should be noted that the equivalent full-bridge rectifier circuit and application scenario described in the embodiment of the present invention are for the purpose of more clearly illustrating the technical solution of the embodiment of the present invention, and do not constitute a limitation on the technical solution provided by the embodiment of the present invention. Those skilled in the art can know that with the evolution of the equivalent full-bridge rectifier circuit and the emergence of new application scenarios, the technical solution provided by the embodiment of the present invention is also applicable to similar technical problems.

[0058] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. An equivalent full-bridge rectifier circuit, characterized in that: include: A first switching element, a second switching element, a third switching element, a fourth switching element, a transformer, an output positive electrode, an output negative electrode, a first auxiliary switching element, a second auxiliary switching element, a third auxiliary switching element, and a fourth auxiliary switching element; Wherein, the transformer comprises a first secondary winding and a second secondary winding; The same-name end of the first secondary winding is connected to the first end of the first switch element, the opposite-name end of the first secondary winding is connected to the second end of the fourth switch element, the second end of the first switch element is connected to the output positive electrode, and the first end of the fourth switch element is connected to the output negative electrode, so that the first secondary winding, the first switch element and the fourth switch element form a first rectification circuit when an AC input positive polarity voltage is applied; The same-name end of the second secondary winding is connected to the second end of the third switch element, the opposite-name end of the second secondary winding is connected to the first end of the second switch element, the second end of the second switch element is connected to the output positive electrode, and the first end of the third switch element is connected to the output negative electrode, so that the second secondary winding, the second switch element and the third switch element form a second rectification circuit when an AC input negative polarity voltage is applied; The first end of the first auxiliary switch element is respectively connected to the same-name end of the second secondary winding and the second end of the third switch element, the second end of the first auxiliary switch element is connected to the output positive electrode, the first end of the fourth auxiliary switch element is connected to the output negative electrode, and the second end of the fourth auxiliary switch element is respectively connected to the opposite-name end of the second secondary winding and the first end of the second switch element, so that the second secondary winding, the first auxiliary switch element and the fourth auxiliary switch element form a third rectification loop in the case of an AC input negative polarity voltage; The second end of the third auxiliary switching element is respectively connected to the same-name end of the first secondary winding and the first end of the first switching element, the first end of the third auxiliary switching element is connected to the output negative electrode, the second end of the second auxiliary switching element is connected to the output positive electrode, and the first end of the second auxiliary switching element is respectively connected to the opposite-name end of the first secondary winding and the second end of the fourth switching element, so that the first secondary winding, the third auxiliary switching element and the second auxiliary switching element form a fourth rectification circuit when an AC input positive polarity voltage is applied.

2. The equivalent full-bridge rectifier circuit according to claim 1, characterized in that: The first switch element, the second switch element, the third switch element and the fourth switch element all include: diode; or, A first bidirectional controllable switch device and a diode connected in parallel; or, A second bidirectional controllable switch device, wherein the second bidirectional controllable switch device is parasitic with an anti-parallel diode.

3. The equivalent full-bridge rectifier circuit according to claim 1, characterized in that: The first auxiliary switch element, the second auxiliary switch element, the third auxiliary switch element and the fourth auxiliary switch element all include: diode; or, at least two diodes connected in series; or, A resistor and a diode connected in series.

4. The equivalent full-bridge rectifier circuit according to claim 2, characterized in that: When the first switch element, the second switch element, the third switch element and the fourth switch element all include: a diode, or a first bidirectional controllable switch device and a diode connected in parallel, the first ends of the first switch element, the second switch element, the third switch element and the fourth switch element are all positive electrodes of the diodes, and the second ends of the first switch element, the second switch element, the third switch element and the fourth switch element are all negative electrodes of the diodes.

5. The equivalent full-bridge rectifier circuit according to claim 2, characterized in that: The first bidirectional controllable switch device and the second bidirectional controllable switch device both include MOSFET or IGBT.

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