Inverter pre-stage boost circuit and PCB
By designing an inverter preamplifier step-up circuit with two secondary windings on the secondary side of the transformer, the problems of high cost and large space occupation of step-up circuits are solved, achieving cost reduction and space saving, and making it suitable for low-voltage, high-current products.
Patent Information
- Application Number
- CN202520336542.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-27
- Publication Date
- 2026-01-23
- Estimated Expiration
- 2035-02-27
AI Technical Summary
Existing boost circuits suffer from high cost and large PCB space requirements.
An inverter preamplifier step-up circuit design with two secondary windings on the secondary side of the transformer is adopted. The step-up is achieved by connecting NMOS transistors and capacitors in combination, and multiple windings are connected in parallel on the secondary side to reduce winding impedance.
While ensuring reliable voltage boosting, it reduces the number of transformers used, lowers costs, and reduces PCB board space requirements, making it suitable for low-voltage, high-current products.
Smart Images
Figure CN223829243U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of boost technology, and in particular to an inverter preamp boost circuit and PCB board. Background Technology
[0002] During the DC-to-AC conversion process, since the AC voltage amplitude is higher than the DC voltage, the DC input voltage (such as that of a battery or solar photovoltaic panel) needs to be boosted before the inverter is activated. This is usually done using a full-bridge or half-bridge sampling method.
[0003] When the DC input voltage is relatively low while the AC output power is relatively high, the DC current is very large. To solve this problem, multiple transformers are usually connected in parallel. As a result, the number of transformers also increases accordingly.
[0004] However, adding transformers will inevitably increase costs and consume PCB space. Utility Model Content
[0005] The technical problem to be solved by this utility model embodiment is that existing boost circuits are expensive and occupy a large PCB space.
[0006] To address the aforementioned problems, in a first aspect, this utility model proposes an inverter pre-amplifier boost circuit, comprising a transformer, a first switching transistor, a second switching transistor, a third switching transistor, a fourth switching transistor, a fifth switching transistor, a sixth switching transistor, a first capacitor, and a second capacitor; the primary side of the transformer has a primary winding, and the secondary side of the transformer has a first secondary winding and a second secondary winding; the primary winding is connected to and grounded by the first capacitor, and the first capacitor is connected to both ends of the second capacitor through the fifth switching transistor and the sixth switching transistor respectively; the center tap of the first secondary winding is connected to a voltage source, and both ends of the first secondary winding are grounded through the first switching transistor and the second switching transistor respectively; the center tap of the second secondary winding is connected to a voltage source, and both ends of the second secondary winding are grounded through the third switching transistor and the fourth switching transistor respectively.
[0007] A further technical solution is that the first switching transistor is an NMOS transistor, the drain of the first switching transistor is connected to the first input pin of the first secondary winding, the source of the first switching transistor is grounded, and the gate of the first switching transistor is connected to the control unit.
[0008] A further technical solution is that the second switching transistor is an NMOS transistor, the drain of the second switching transistor is connected to the second input pin of the first secondary winding, the source of the second switching transistor is grounded, and the gate of the second switching transistor is connected to the control unit.
[0009] A further technical solution is that the third switch is an NMOS transistor, the drain of the third switch is connected to the first input pin of the second secondary winding, the source of the third switch is grounded, and the gate of the third switch is connected to the control unit.
[0010] A further technical solution is that the fourth switch is an NMOS transistor, the drain of the fourth switch is connected to the second input pin of the second secondary winding, the source of the fourth switch is grounded, and the gate of the fourth switch is connected to the control unit.
[0011] A further technical solution is that the fifth switch is an NMOS transistor, the source of the fifth switch is grounded, the drain of the fifth switch is connected to the first capacitor, and the gate of the fifth switch is connected to the control unit.
[0012] A further technical solution is that the sixth switch is an NMOS transistor, the source of the sixth switch is connected to the first capacitor, the drain of the sixth switch is connected to the second capacitor, and the gate of the sixth switch is connected to the control unit.
[0013] A further technical solution is that the first secondary winding and the second secondary winding are wound on the same magnetic core.
[0014] A further technical solution is that the second capacitor is an electrolytic capacitor.
[0015] Secondly, this utility model embodiment provides a PCB board, the PCB board including the inverter preamp boost circuit as described in the first aspect.
[0016] Compared with the prior art, the technical effects achieved by the embodiments of this utility model include:
[0017] In the inverter preamp boost circuit proposed in this embodiment, the primary side of the transformer has a primary winding, and the secondary side of the transformer has a first secondary winding and a second secondary winding. The primary winding is connected to and grounded to the first capacitor, and the first capacitor is connected to the two ends of the second capacitor through the fifth and sixth switching transistors, respectively. The center tap of the first secondary winding is connected to a voltage source, and the two ends of the first secondary winding are grounded through the first and second switching transistors, respectively. The center tap of the second secondary winding is connected to a voltage source, and the two ends of the second secondary winding are grounded through the third and fourth switching transistors, respectively. It can be seen that by setting two secondary windings on the secondary side of the transformer, reliable voltage boosting can be ensured while reducing the use of transformers, thereby reducing costs and PCB board space occupation.
[0018] Furthermore, the technical solution of this utility model embodiment can easily realize the parallel connection of multiple windings on the secondary side, reducing the impedance of the secondary winding; and can realize the parallel connection of non-integer turns, making the transformer design more flexible, especially suitable for low-voltage high-current products. Attached Figure Description
[0019] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the present invention and, together with the description, serve to explain the principles of the present invention.
[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0021] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.
[0022] Figure 1 A circuit diagram of an inverter preamp boost circuit proposed in an embodiment of this utility model;
[0023] Figure 2 This is the winding diagram of the secondary side of the transformer in the case of an integer number of turns on the secondary side, as proposed in this embodiment of the utility model.
[0024] Figure 3 This is the winding diagram of the primary side of the transformer in the case of an integer number of turns on the secondary side, as proposed in this embodiment of the utility model.
[0025] Figure 4 The winding diagram of the secondary side of the transformer in scenario 1 with multiple turns on the secondary side, as proposed in this embodiment of the present invention;
[0026] Figure 5 The winding diagram of the primary side of the transformer in scenario 1 with a fractional turn configuration on the secondary side, as proposed in this embodiment of the present invention;
[0027] Figure 6 This is a schematic diagram of the transformer structure in scenario 1, where the transformer has a fractional number of turns on the secondary side, as proposed in this embodiment of the present invention.
[0028] Figure 7 The winding diagram of the secondary side of the transformer in scenario 2 with a fractional turn configuration on the secondary side, as proposed in this embodiment of the present invention;
[0029] Figure 8The winding diagram of the primary side of the transformer in scenario 2 with a fractional turn configuration on the secondary side, as proposed in this embodiment of the present invention;
[0030] Figure 9 This is a schematic diagram of the transformer structure in scenario 2, where the transformer has a fractional number of turns on the secondary side, as proposed in this embodiment of the present invention.
[0031] Figure Labels
[0032] Transformer T1, first switch Q1, second switch Q2, third switch Q3, fourth switch Q4, fifth switch Q5, sixth switch Q6, first capacitor C1, and second capacitor E1. Detailed Implementation
[0033] The technical solutions in the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Similar component reference numerals in the drawings represent similar components. Obviously, the embodiments described below are only some embodiments of this utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.
[0034] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.
[0035] It should also be understood that the terminology used in this specification of embodiments of the present invention is for the purpose of describing particular embodiments only and is not intended to limit the embodiments of the present invention. As used in this specification of embodiments of the present invention and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.
[0036] See Figures 1-5 This utility model embodiment proposes an inverter pre-stage boost circuit, which includes a transformer T1, a first switch Q1, a first switch Q2, a third switch Q3, a fourth switch Q4, a fifth switch Q5, a sixth switch Q6, a first capacitor C1, and a second capacitor C2, as detailed below:
[0037] The primary side of the transformer T1 is provided with a primary winding, and the secondary side of the transformer T1 is provided with a first secondary winding and a second secondary winding.
[0038] The primary winding is connected to and grounded by the first capacitor C1. The first capacitor C1 is connected to both ends of the second capacitor C2 through the fifth switch Q5 and the sixth switch Q6. The second capacitor C2 can be an electrolytic capacitor, and the voltage stored in the second capacitor C2 is used to provide energy for the subsequent inverter.
[0039] The center tap (pin 4) of the first secondary winding is connected to a voltage source, and the two ends of the first secondary winding are grounded through the first switch Q1 and the first switch Q2, respectively. The center tap (pin 7) of the second secondary winding is connected to a voltage source, and the two ends of the second secondary winding are grounded through the third switch Q3 and the fourth switch Q4, respectively. The voltage source can be a DC power source such as a battery or a photovoltaic panel; however, this invention does not specifically limit its application.
[0040] Working principle
[0041] The second switch Q2 and the fourth switch Q4 are simultaneously turned on, and the first switch Q1 and the third switch Q3 are simultaneously turned on, complementing the second switch Q2 and the fourth switch Q4. When the second switch Q2 and the fourth switch Q4 are turned on, pin 1 of transformer T1 is positive, and the current path is: pin 1 of transformer T1 → fifth switch Q5 → first capacitor C1 → pin 2 of transformer T1 → pin 1 of transformer T1; the voltage of the first capacitor C1 is charged to n*Vin (n is the turns ratio, Vin is the voltage of the voltage source), and the sixth switch Q6 is turned off. When the first switch Q1 and the third switch Q3 are turned on, the current direction is: pin 2 of transformer T1 → first capacitor C1 → sixth switch Q6 → second capacitor E1 → pin 1 of transformer T1 → pin 2 of transformer T1; at this time, the voltage of the first capacitor C1 is superimposed on the voltage of the transformer T1 winding, and the voltage of the second capacitor E1 is charged to 2n*Vin. The voltage of the second capacitor E1 provides energy for the subsequent inverter.
[0042] In the inverter preamp boost circuit proposed in this embodiment, the primary side of transformer T1 is provided with a primary winding, and the secondary side of transformer T1 is provided with a first secondary winding and a second secondary winding. The primary winding is connected to and grounded to the first capacitor C1, and the first capacitor C1 is connected to the two ends of the second capacitor C2 through the fifth switch Q5 and the sixth switch Q6 respectively. The center tap of the first secondary winding is connected to a voltage source, and the two ends of the first secondary winding are grounded through the first switch Q1 and the first switch Q2 respectively. The center tap of the second secondary winding is connected to a voltage source, and the two ends of the second secondary winding are grounded through the third switch Q3 and the fourth switch Q4 respectively. It can be seen that by setting two secondary windings on the secondary side of transformer T1, reliable boosting can be ensured while reducing the use of transformer T1, thereby reducing costs and PCB board space occupation.
[0043] Furthermore, the technical solution of this utility model embodiment can easily realize the parallel connection of multiple windings on the secondary side, reducing the impedance of the secondary winding; and can realize the parallel connection of non-integer turns, making the transformer design more flexible, especially suitable for low-voltage high-current products.
[0044] Specifically, in some embodiments, such as this embodiment, the first switch Q1 is an NMOS transistor. The drain of the first switch Q1 is connected to the first input pin of the first secondary winding, the source of the first switch Q1 is grounded, and the gate of the first switch Q1 is connected to the control unit. Specifically, the first input pin of the first secondary winding can be specifically... Figure 1 Pin 8 in the middle.
[0045] Further, the first switch Q2 is an NMOS transistor, the drain of the first switch Q2 is connected to the second input pin of the first secondary winding, the source of the first switch Q2 is grounded, and the gate of the first switch Q2 is connected to the control unit. Specifically, the second input pin of the first secondary winding is... Figure 1 Pin 6 in the middle.
[0046] Further, the third switch Q3 is an NMOS transistor. The drain of the third switch Q3 is connected to the first input pin of the second secondary winding, the source of the third switch Q3 is grounded, and the gate of the third switch Q3 is connected to the control unit. Specifically, the first input pin of the second secondary winding is... Figure 1 Pin 5 in the middle.
[0047] Further, the fourth switch Q4 is an NMOS transistor. The drain of the fourth switch Q4 is connected to the second input pin of the second secondary winding, the source of the fourth switch Q4 is grounded, and the gate of the fourth switch Q4 is connected to the control unit. Specifically, the second input pin of the second secondary winding is... Figure 1 Pin 3 in the middle.
[0048] Furthermore, the fifth switch Q5 is an NMOS transistor, the source of the fifth switch Q5 is grounded, the drain of the fifth switch Q5 is connected to the first capacitor C1, and the gate of the fifth switch Q5 is connected to the control unit.
[0049] Furthermore, the sixth switch Q6 is an NMOS transistor, the source of the sixth switch Q6 is connected to the first capacitor C1, the drain of the sixth switch Q6 is connected to the second capacitor C2, and the gate of the sixth switch Q6 is connected to the control unit.
[0050] It is understood that the first switch Q1, the first switch Q2, the third switch Q3, the fourth switch Q4, the fifth switch Q5, and the sixth switch Q6 may also be other types of switching devices, which will not exceed the protection scope of this utility model. Therefore, this utility model does not specifically limit them.
[0051] In some embodiments, such as this one, the first secondary winding and the second secondary winding are wound on the same magnetic core.
[0052] For example, Scheme 1, the integer turn scenario on the secondary side.
[0053] See Figures 2-3 The first secondary winding of transformer T1 starts clockwise from pin 8 and ends at pin 6, with pin 4 serving as the center tap. The second secondary winding starts clockwise from pin 3 and ends at pin 5, with pin 7 serving as the center tap. Both the first and second secondary windings are mounted on the same magnetic core. The primary winding uses a conventional winding method.
[0054] Option 2, Secondary Side Fractional Turns Scenario 1
[0055] See Figures 4-6 The first secondary winding of transformer T1 starts clockwise from pin 8 and ends at pin 6, with pin 4 serving as the center tap. The second secondary winding starts clockwise from pin 3 and ends at pin 5, with pin 7 serving as the center tap. Both the first and second secondary windings are mounted on the same magnetic core. The primary winding uses a conventional winding method. In this scenario, the transformer ratio is 0.5:N. See the structural diagram of transformer T1 in this scenario. Figure 6 The power of transformer T1 is 500W.
[0056] Secondary side fractional turn scenario 2
[0057] See Figures 7-9 , Figure 6 The yellow portion represents the center taps of the first and second secondary windings of transformer T1. The Ae value of the four terminals is 1 / 4 of that of the center terminal. The first secondary winding consists of four smaller windings: 3 starting and 9 ending, 4 starting and 13 ending, 1 starting and 12 ending, and 2 starting and 8 ending. Figure 6 The red section in the middle. The second secondary winding consists of four smaller windings: 3 starting and 5 ending, 4 starting and 6 ending, 1 starting and 7 ending, and 2 starting and 11 ending, i.e. Figure 6 The blue section shows the two groups mounted on the same magnetic core. The primary winding uses a conventional method, and the transformer ratio implemented in this scenario is 0.25:N. See the structural diagram of transformer T1 in this scenario. Figure 9 The power of transformer T1 is 1000W.
[0058] This utility model embodiment proposes a PCB board, which includes an inverter preamp boost circuit as proposed in any of the above embodiments.
[0059] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.
[0060] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.
[0061] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.
[0062] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0063] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0064] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. The illustrative expressions of the above terms in this specification should not be construed as necessarily referring to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.
[0065] Obviously, those skilled in the art can make various modifications and variations to this utility model without departing from its spirit and scope. Since these modifications and variations fall within the scope of the claims of this utility model and their equivalents, this utility model also intends to include these modifications and variations.
[0066] The above description describes specific embodiments of this utility model, but the scope of protection of this utility model is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this utility model, and these modifications or substitutions should all be covered within the scope of protection of this utility model. Therefore, the scope of protection of this utility model should be determined by the scope of the claims.
Claims
1. A boost converter circuit before an inverter, characterized in that, The system includes a transformer, a first switch, a second switch, a third switch, a fourth switch, a fifth switch, a sixth switch, a first capacitor, and a second capacitor. The transformer has a primary winding on its primary side and a first secondary winding and a second secondary winding on its secondary side. The primary winding is connected to and grounded to the first capacitor. The first capacitor is connected to both ends of the second capacitor through the fifth switch and the sixth switch, respectively. The center tap of the first secondary winding is connected to a voltage source, and both ends of the first secondary winding are grounded through the first switch and the second switch, respectively. The center tap of the second secondary winding is connected to a voltage source, and both ends of the second secondary winding are grounded through the third switch and the fourth switch, respectively.
2. The inverter preamp boost circuit according to claim 1, characterized in that, The first switching transistor is an NMOS transistor. The drain of the first switching transistor is connected to the first input pin of the first secondary winding, the source of the first switching transistor is grounded, and the gate of the first switching transistor is connected to the control unit.
3. The inverter preamp boost circuit according to claim 1, characterized in that, The second switching transistor is an NMOS transistor. The drain of the second switching transistor is connected to the second input pin of the first secondary winding, the source of the second switching transistor is grounded, and the gate of the second switching transistor is connected to the control unit.
4. The inverter preamp boost circuit according to claim 1, characterized in that, The third switch is an NMOS transistor. The drain of the third switch is connected to the first input pin of the second secondary winding, the source of the third switch is grounded, and the gate of the third switch is connected to the control unit.
5. The inverter preamp boost circuit according to claim 1, characterized in that, The fourth switch is an NMOS transistor. The drain of the fourth switch is connected to the second input pin of the second secondary winding, the source of the fourth switch is grounded, and the gate of the fourth switch is connected to the control unit.
6. The inverter preamp boost circuit according to claim 1, characterized in that, The fifth switch is an NMOS transistor, with its source grounded, its drain connected to the first capacitor, and its gate connected to the control unit.
7. The inverter preamp boost circuit according to claim 1, characterized in that, The sixth switch is an NMOS transistor. The source of the sixth switch is connected to the first capacitor, the drain of the sixth switch is connected to the second capacitor, and the gate of the sixth switch is connected to the control unit.
8. The inverter preamp boost circuit according to claim 1, characterized in that, The first secondary winding and the second secondary winding are wound on the same magnetic core.
9. The inverter preamp boost circuit according to claim 1, characterized in that, The second capacitor is an electrolytic capacitor.
10. A PCB board, characterized in that, Including the inverter preamp boost circuit as described in any one of claims 1-9.