Transformer, converter for realizing wide voltage range based on transformer and control method of converter

Abstract

The invention provides a transformer, a wide-voltage-range converter based on the transformer and a control method of the wide-voltage-range converter. The transformer is characterized in that a first winding of a first side column is provided with a first terminal, and a second winding of a second side column is provided with a second terminal; the first middle winding of the middle column is provided with a first middle terminal; the first terminal, the second terminal and the first intermediate terminal are arranged on the same side of the magnetic core; the third winding of the first side column is provided with a third terminal, and the fourth winding of the second side column is provided with a fourth terminal; the second middle winding of the middle column is provided with a second middle terminal; the third terminal, the fourth terminal and the second intermediate terminal are arranged on the same side of the magnetic core; the transformer can present different primary side equivalent winding turns and secondary side equivalent winding turns in a circuit, and the voltage regulation range is expanded.

Description

[0001] This application claims the priority of a Chinese invention patent application with the application number 202411995530.4 and filed on December 31, 2024. Technical Field

[0002] The present disclosure relates to the field of power electronics, and in particular, to a transformer, a converter with a wide voltage range implemented based on the transformer, and a control method thereof. Background Art

[0003] The voltage conditions of existing transformers and converters based on transformers are difficult to expand, resulting in low voltage conversion efficiency. Summary of the Invention

[0004] The present disclosure provides a transformer, a converter with a wide voltage range implemented based on the transformer, and a control method thereof, so as to solve to some extent the technical problems such as the inextendable voltage regulation range and low voltage conversion efficiency of the transformer and the converter based on the transformer.

[0005] In a first aspect of the present disclosure, a transformer is provided, including:

[0006] A magnetic core, including a first side leg, a middle leg, and a second side leg, for providing a magnetic path;

[0007] A first winding disposed on the first side leg, the first winding being provided with a first terminal;

[0008] A second winding disposed on the second side leg, the second winding being provided with a second terminal; the number of turns of both the first winding and the second winding is a first number of turns n1;

[0009] A first intermediate winding disposed on the middle leg, the first intermediate winding being provided with a first intermediate terminal; the first terminal, the second terminal, and the first intermediate terminal are disposed on the same side of the magnetic core, and the number of turns of the first intermediate winding is a second number of turns k1; the first number of turns n1 is a positive integer, and the second number of turns k1 is a non-negative integer;

[0010] A third winding disposed on the first side leg, the third winding being provided with a third terminal;

[0011] A fourth winding disposed on the second side leg, the fourth winding being provided with a fourth terminal; the number of turns of both the third winding and the fourth winding is a third number of turns n2;

[0012] The second intermediate winding disposed on the middle column, and the second intermediate winding is provided with a second intermediate terminal; the third terminal, the fourth terminal, and the second intermediate terminal are disposed on the same side of the magnetic core, and the number of turns of the second intermediate winding is the fourth number of turns k2; the third number of turns n2 is a positive integer, and the fourth number of turns k2 is a non-negative integer;

[0013] Wherein, the relative relationship between the winding directions of the first winding and the second winding with respect to the first intermediate winding is different, so that the transformer presents different primary-side equivalent winding turns in the circuit;

[0014] The relative relationship between the winding directions of the third winding and the fourth winding with respect to the second intermediate winding is different, so that the transformer presents different secondary-side equivalent winding turns in the circuit.

[0015] In a second aspect of the present disclosure, a converter is provided, including:

[0016] An inverter-side circuit for converting an input DC voltage into a first AC voltage; the inverter-side circuit includes a first bridge arm and a second bridge arm connected in parallel, the first bridge arm includes a first switch and a second switch connected in series, and the second bridge arm includes a third switch and a fourth switch connected in series;

[0017] A transformer circuit, the primary side of the transformer circuit is connected to the first connection point of the first switch and the second switch, and the second connection point of the third switch and the fourth switch, for converting the first AC voltage into a second AC voltage;

[0018] A rectifier-side circuit connected to the secondary side of the transformer circuit for converting the second AC voltage into an output DC voltage;

[0019] Wherein, the transformer circuit includes the transformer according to the first aspect.

[0020] In a third aspect of the present disclosure, a control method for a converter according to the second aspect is provided, including:

[0021] Controlling the relative phase-shifting time of the first bridge arm and the second bridge arm to adjust the ratio of the equivalent winding turns of the transformer.

[0022] As can be seen from the above, a transformer provided by the present disclosure, a converter with a wide voltage range implemented based on the transformer, and a control method thereof set side column windings and middle column intermediate windings on both the primary side and the secondary side of the transformer, and by changing the relative relationship between the winding directions of the side column windings and the intermediate windings, the transformer can present different equivalent winding turns on the primary side and the secondary side in the circuit, enhancing the flexibility and adaptability of the transformer. Further, a converter using the above transformer is provided to achieve wide voltage range regulation of the converter. Further, a control method based on the converter is provided. By precisely controlling the relative phase shift time of the two bridge arms in the inverter side circuit, the equivalent winding turn ratio of the transformer is dynamically adjusted, thereby achieving fine regulation of the output voltage, significantly improving the energy efficiency ratio and voltage regulation accuracy of the converter. Furthermore, a variety of modulation methods are used to broaden the voltage regulation range of the converter. It not only significantly improves the efficiency of voltage conversion, but also enhances the flexibility and adaptability of the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the present disclosure or related technologies, the following will briefly introduce the drawings required for use in the embodiments or related technology descriptions. Obviously, the drawings in the following description are only the embodiments of the present disclosure. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0024] Figure 1 Schematic diagram of the transformer according to an embodiment of the present disclosure.

[0025] Figure 2 Schematic diagram of the primary side of the transformer according to an embodiment of the present disclosure.

[0026] Figure 3 Schematic diagram showing that the winding directions of the windings on the side column and the middle column of the transformer according to an embodiment of the present disclosure are opposite.

[0027] Figure 4 Schematic diagram showing that the winding directions of the windings on the side column and the middle column of the transformer according to an embodiment of the present disclosure are the same.

[0028] Figure 5 Schematic diagram of the secondary side of the transformer according to an embodiment of the present disclosure.

[0029] Figure 6 Schematic diagram of the converter according to an embodiment of the present disclosure.

[0030] Figure 7 Pulse timing diagram of the inverter side switch according to an embodiment of the present disclosure.

[0031] Figure 8 Schematic diagram of the primary side of the transformer according to an embodiment of the present disclosure in the in-phase operation mode.

[0032] Figure 9 This is the equivalent circuit of the transformer when the primary side of the transformer in the embodiment of the present disclosure is in the in-phase operation mode.

[0033] Figure 10 This is a schematic diagram of the primary side of the transformer in the embodiment of the present disclosure in the anti-phase operation mode.

[0034] Figure 11 This is the equivalent circuit of the transformer when the primary side of the transformer in the embodiment of the present disclosure is in the anti-phase operation mode. Detailed implementation manners

[0035] In order to make the objectives, technical solutions and advantages of the present disclosure more clear and understandable, the present disclosure will be further described in detail below with reference to specific embodiments and the accompanying drawings.

[0036] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present disclosure should have the ordinary meanings understood by those of ordinary skill in the art to which the present disclosure belongs. The "first", "second" and similar terms used in the embodiments of the present disclosure do not denote any order, quantity or importance, but are only used to distinguish different components. The terms such as "including" or "comprising" mean that the elements or objects appearing before this term cover the elements or objects listed after this term and their equivalents, without excluding other elements or objects. The terms such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms such as "upper", "lower", "left" and "right" are only used to represent relative positional relationships, and when the absolute position of the object to be described changes, the relative positional relationship may also change accordingly.

[0037] In traditional isolated converters, in addition to the isolation function, the transformer also plays the function of stepping up or stepping down the voltage. However, in the traditional winding method, once the transformer is manufactured, the turns ratio of the primary side and the secondary side windings is fixed, and thus the voltage transformation ratio shown in the circuit is also fixed. In this case, the voltage regulation range covered by the converter using the traditional isolated converter is only determined by the topology structure and control method of the converter itself. Therefore, how to expand the voltage regulation range of the transformer and the converter has become an urgent technical problem to be solved.

[0038] In view of this, a transformer provided by an embodiment of the present disclosure, a converter with a wide voltage range implemented based on the transformer, and a control method thereof. By arranging side column windings and middle column middle windings on both the primary side and the secondary side of the transformer, and by changing the relative relationship between the winding directions of the side column windings and the middle windings, the transformer can present different equivalent winding turns on the primary side and the secondary side in the circuit, enhancing the flexibility and adaptability of the transformer. Further, a converter using the above transformer is provided to achieve wide voltage range adjustment of the converter. Further, a control method based on the transformer is provided. By precisely controlling the relative phase shift time of two bridge arms in the inverter side circuit, the equivalent winding turn ratio of the transformer is dynamically adjusted, thereby achieving fine adjustment of the output voltage, significantly improving the energy efficiency ratio and voltage regulation accuracy of the converter. Furthermore, various modulation methods are adopted to broaden the voltage regulation range of the converter. Not only significantly improves the efficiency of voltage conversion, but also enhances the flexibility and adaptability of the circuit.

[0039] See Figure 1 , Figure 1 shows a schematic diagram of a transformer according to an embodiment of the present disclosure. Figure 1 In [the figure], the transformer includes a magnetic core, and the magnetic core includes a first side column, a middle column, and a second side column. The primary side winding and the secondary side winding are respectively wound on the corresponding middle column and side column.

[0040] In some embodiments, the magnetic core may have multiple windows, and each window includes a middle column and a corresponding side column. For example, if the magnetic core is a 2-window magnetic core (such as EE, EI, PQ, RM, etc.), the magnetic core can include a middle column and two side columns. The two side columns can be in the same plane as the middle column, that is, with the middle column as the center, the included angle between the connecting lines of the two side columns and the center is 180°. For another example, if the magnetic core is a 3-window magnetic core, the magnetic core can include a middle column and three side columns. With the middle column as the center, the included angle between the connecting lines of the three side columns and the center can be 120°. For another example, if the magnetic core is a 4-window magnetic core, the magnetic core can include a middle column and four side columns. With the middle column as the center, the included angle between the connecting lines of the four side columns and the center can be 90°. It should be understood that the number of windows is the same as the number of side columns, and the number of side columns can be set as needed and is not limited here. Each side column can be evenly symmetrically distributed along the circumference based on the center.

[0041] The present disclosure provides a transformer, including:

[0042] A magnetic core, including a first side column, a middle column, and a second side column, for providing a magnetic path;

[0043] A first winding disposed on the first side column, and the first winding is provided with a first terminal;

[0044] The second winding disposed on the second side column, the second winding being provided with a second terminal; the number of turns of both the first winding and the second winding is a first number of turns n1;

[0045] The first intermediate winding disposed on the middle column, the first intermediate winding being provided with a first intermediate terminal; the first terminal, the second terminal, and the first intermediate terminal are disposed on the same side of the magnetic core, the number of turns of the first intermediate winding is a second number of turns k1; the first number of turns n1 is a positive integer, and the second number of turns k1 is a non-negative integer;

[0046] The third winding disposed on the first side column, the third winding being provided with a third terminal;

[0047] The fourth winding disposed on the second side column, the fourth winding being provided with a fourth terminal; the number of turns of both the third winding and the fourth winding is a third number of turns n2;

[0048] The second intermediate winding disposed on the middle column, the second intermediate winding being provided with a second intermediate terminal; the third terminal, the fourth terminal, and the second intermediate terminal are disposed on the same side of the magnetic core, the number of turns of the second intermediate winding is a fourth number of turns k2; the third number of turns n2 is a positive integer, and the fourth number of turns k2 is a non-negative integer;

[0049] Wherein, the relative relationship between the winding directions of the first winding and the second winding and the first intermediate winding is different, so that the transformer presents different equivalent primary winding turns in the circuit;

[0050] The relative relationship between the winding directions of the third winding and the fourth winding and the second intermediate winding is different, so that the transformer presents different equivalent secondary winding turns in the circuit.

[0051] Wherein, the equivalent winding turns can refer to the equivalent value of the winding turns in terms of electrical performance under the condition of keeping the air-gap magnetomotive force the same. When an alternating voltage is applied to the primary winding, an alternating current flows into the primary winding to generate an exciting effect, and an alternating magnetic flux is generated in the iron core. This alternating magnetic flux passes through both the primary winding and the secondary winding at the same time, and induces electromotive forces in the two windings respectively. The winding direction affects the direction of the induced electromotive force. If the winding directions of two windings are the same (wound in the same phase), their induced electromotive force directions are also the same; if the winding directions are opposite (wound in opposite phases), the induced electromotive force directions are also opposite. By adjusting the relative relationship between the winding directions of the first, second, third, and fourth windings and the corresponding intermediate windings, the equivalent primary and secondary winding turns presented by the transformer in the circuit can be flexibly changed, so as to realize various voltage conversions and circuit requirements, increasing the flexibility and adaptability of the transformer.

[0052] SeeFigure 2 , Figure 2 shows a schematic diagram of the primary side of a transformer according to an embodiment of the present disclosure. Figure 2 In this, the transformer may include: a magnetic core including a first side leg, a middle leg, and a second side leg for providing a magnetic path;

[0053] a first winding disposed on the first side leg, the first winding being provided with a first terminal;

[0054] a second winding disposed on the second side leg, the second winding being provided with a second terminal; the number of turns of both the first winding and the second winding is a first number of turns n1;

[0055] a first intermediate winding disposed on the middle leg, the first intermediate winding being provided with a first intermediate terminal; the first terminal, the second terminal, and the first intermediate terminal are disposed on the same side of the magnetic core, and the number of turns of the first intermediate winding is a second number of turns k1; the first number of turns n1 is a positive integer, and the second number of turns k1 is a non - negative integer.

[0056] Among them, the number of turns of the first winding and the second winding may be equal and be positive integers. The number of turns of the first intermediate winding may be 0. The first terminal A1, the second terminal B1, and the first intermediate terminal M1 are arranged on the same side of the magnetic core, that is, the starting end and the terminating end of the primary - side winding (for example, one of the first terminal A1 and the second terminal B1 may be the starting end, and the other terminal is the terminating end) and the center tap are arranged on the same side of the magnetic core. As Figure 2 shown in, the first terminal A1, the second terminal B1, and the first intermediate terminal M1 are all located on the same side of the top view of the magnetic core, that is, the winding lead - out side. The winding lead - out side relative to the other side of the magnetic core can be used as the determination side for the number of turns of the primary - side winding, that is, if the winding lead - out side is on one side of the magnetic core, then the other side of the magnetic core opposite to this side can be the determination side. Based on this determination side for the number of turns of the primary - side winding, the actual number of turns of the first winding, the second winding, and the first intermediate winding can be determined. For example, n1 = 3, k1 = 4.

[0057] In some embodiments, the relative relationship between the winding directions of the first winding and the second winding and the first intermediate winding is different, such that the transformer presents different equivalent number of turns of the primary side in a circuit.

[0058] Among them, the winding directions (clockwise or counterclockwise) of both the first winding and the second winding are not exactly the same as that of the first intermediate winding when being wound, and they can be the same or different. The turns ratio of the transformer determines its voltage transformation ratio. Due to the different winding directions, the transformer can exhibit the effect of different equivalent winding turns on the primary side in the circuit. In fact, the physical number of turns of the winding has not changed, but due to the influence of the winding direction (such as factors like mutual inductance and coupling), the transformer can present different voltage transformation ratios in the circuit, thereby presenting a varying number of turns on the primary side, which is beneficial to expanding the voltage regulation range of the transformer.

[0059] In some embodiments, when both the first winding and the second winding are wound in the opposite direction to the first intermediate winding, the equivalent winding turns on the primary side of the transformer are the first number of turns n1, or the sum n1 + k1 of the first number of turns n1 and the second number of turns k1.

[0060] Specifically, referring to Figure 3 , Figure 3 shows a schematic diagram of the winding directions of the windings on the side columns and the middle column of the transformer according to an embodiment of the present disclosure being opposite. Figure 3 In, if the first terminal A1 is used as the starting end of the winding of the primary side winding coil, it can be seen that the coils of the primary side winding on the first side column and the second side column are wound counterclockwise, and the coil of the middle column is wound clockwise. Therefore, there are two turn states of the primary side winding of the transformer, which are |n1 + k1| = 7 and |n1| = 3 respectively. If the windings on the first side column and the second side column are wound clockwise for 3 turns and the middle column is wound counterclockwise for 4 turns, the two turn states existing in the primary side winding are also |n1 + k1| = 7 and |n1| = 3 respectively.

[0061] In some embodiments, when both the first winding and the second winding are wound in the same direction as the first intermediate winding, the equivalent winding turns on the primary side of the transformer are the first number of turns n1, or the absolute value |n1 - k1| of the difference between the first number of turns n1 and the second number of turns k1.

[0062] Specifically, referring to Figure 4 , Figure 4 shows a schematic diagram of the winding directions of the windings on the side columns and the middle column of the transformer according to an embodiment of the present disclosure being the same. Figure 4In the case where the first terminal A1 is the starting end of the winding of the primary side winding coil, it can be seen that the coils of the primary side winding on the first side leg and the second side leg are wound counterclockwise, and the coil of the middle leg is wound counterclockwise. Therefore, the primary side winding of the transformer has two turn numbers, namely |n1 - k1| = 1 and |n1| = 3. If the windings on the first side leg and the second side leg are wound clockwise for 3 turns and the winding of the middle leg is wound clockwise for 4 turns, the two turn numbers of the primary side winding are also |n1 - k1| = 1 and |n1| = 3 respectively.

[0063] It can be seen that in some embodiments, when the input current flows in from the first terminal A1 and the second terminal B1 and flows out from the first intermediate terminal M1, or when the input current flows in from the first intermediate terminal M1 and flows out from the first terminal A1 and the second terminal B1, the number of turns of the equivalent primary side winding is the first turn number n1. In some embodiments, when the input current flows in from the first terminal A1 and flows out from the second terminal B1, or when the input current flows in from the second terminal B1 and flows out from the first terminal A1, and when both the first winding and the second winding are wound in the opposite direction to that of the first intermediate winding, the number of turns of the equivalent primary side winding is n1 + k1; when both the first winding and the second winding are wound in the same direction as that of the first intermediate winding, the number of turns of the equivalent primary side winding is |n1 - k1|.

[0064] See Figure 5 , Figure 5 which shows a schematic diagram of the secondary side of a transformer according to an embodiment of the present disclosure. Figure 5 In this case, the transformer may further include:

[0065] A third winding disposed on the first side leg, and the third winding is provided with a third terminal;

[0066] A fourth winding disposed on the second side leg, and the fourth winding is provided with a fourth terminal; the number of turns of both the third winding and the fourth winding is the third turn number n2;

[0067] A second intermediate winding disposed on the middle leg, and the second intermediate winding is provided with a second intermediate terminal; the third terminal, the fourth terminal and the second intermediate terminal are disposed on the same side of the magnetic core, and the number of turns of the second intermediate winding is the fourth turn number k2; the third turn number n2 is a positive integer, and the fourth turn number k2 is a non-negative integer.

[0068] Among them, the number of turns of the third winding and the fourth winding can be equal and are positive integers. The number of turns of the second intermediate winding can be 0. The third terminal A2, the fourth terminal B2, and the second intermediate terminal M2 are arranged on the same side of the magnetic core, that is, the starting end and the terminating end of the secondary side winding (for example, one of the third terminal A2 and the fourth terminal B2 can be the starting end, and the other terminal is the terminating end) and the center tap are arranged on the same side of the magnetic core. As Figure 5 shown in, the third terminal A2, the fourth terminal B2, and the second intermediate terminal M2 are all located on the same side of the top view of the magnetic core, that is, the winding lead-out end side. Similar to the primary side, the side of the magnetic core opposite to the winding lead-out end side can be used as the determination side for the number of turns of the secondary side winding, that is, if the winding lead-out end side is on one side of the magnetic core, the other side of the magnetic core is defined as the determination side. Based on this determination side of the number of turns of the secondary side winding, the actual number of turns of the third winding, the fourth winding, and the second intermediate winding can be determined. For example, n2 = 3, k2 = 2.

[0069] In some embodiments, the relative relationship between the winding directions of the third winding and the fourth winding with respect to the second intermediate winding is different, so that the transformer presents different equivalent winding turns on the secondary side in the circuit.

[0070] Among them, the winding directions (clockwise or counterclockwise) of the third winding and the fourth winding with respect to the second intermediate winding can be the same or different. Similar to the primary side, due to the different winding directions, the transformer can show the effect of different equivalent winding turns on the secondary side in the circuit, thus presenting variable turns on the secondary side, which is beneficial to expanding the voltage regulation range of the transformer.

[0071] In some embodiments, when the winding directions of both the third winding and the fourth winding are opposite to that of the second intermediate winding, the equivalent winding turns on the secondary side of the transformer are the third number of turns n2, or the sum n2 + k2 of the third number of turns n2 and the fourth number of turns k2.

[0072] Among them, similar to the primary side, when the coils of the secondary side winding on the first side limb and the second side limb are wound clockwise and the coils of the middle limb are wound counterclockwise, there are two turns states of the secondary side winding of the transformer, which are |n2 + k2| = 5 and |n2| = 3 respectively. If the windings on the first side limb and the second side limb are wound counterclockwise for 3 turns and the middle limb is wound clockwise for 2 turns, the two turns states of the primary side winding are also |n2 + k2| = 5 and |n1| = 3 respectively.

[0073] In some embodiments, when the winding directions of both the third winding and the fourth winding are the same as that of the second intermediate winding, the number of turns of the equivalent secondary winding of the transformer is the third number of turns n2, or the absolute value |n2 - k2| of the difference between the third number of turns n2 and the fourth number of turns k2.

[0074] Among them, similar to the primary side, when the coils of the secondary side winding on the first side leg and the second side leg are wound counterclockwise and the coil of the middle leg is wound counterclockwise, there are two turn states of the secondary side winding of the transformer, which are |n2 - k2| = 1 and |n2| = 3 respectively. If the windings on the first side leg and the second side leg are wound clockwise for 3 turns and the middle leg is wound clockwise for 2 turns, the two turn states of the secondary side winding are also |n2 - k2| = 1 and |n2| = 3 respectively.

[0075] It can be seen that in some embodiments, when the input current flows in from the third terminal A2 and the fourth terminal B2 and flows out from the second intermediate terminal M2, or when the input current flows in from the second intermediate terminal M2 and flows out from the third terminal A2 and the fourth terminal B2, the number of turns of the equivalent secondary winding is the third number of turns n2. In some embodiments, when the input current flows in from the third terminal A2 and flows out from the fourth terminal B2, or when the input current flows in from the fourth terminal B2 and flows out from the third terminal A2, and the winding directions of both the third winding and the fourth winding are opposite to that of the second intermediate winding, the number of turns of the equivalent secondary winding is n2 + k2; when the winding directions of both the third winding and the fourth winding are the same as that of the second intermediate winding, the number of turns of the equivalent secondary winding is |n2 - k2|.

[0076] In some embodiments, the intermediate taps M1 and M2 of the primary side winding and the secondary side winding should be led out from the middle turn of the coil surrounded by the middle leg of the magnetic core on the side of the winding lead-out end. Figure 5 For example, in the top view of the secondary side winding coil, the number of turns of the coil surrounded by the middle leg is k2 = 2 turns (counted from the side for determining the number of winding turns), and there are 3 turns on the side of the winding lead-out end of the coil. Therefore, the second intermediate terminal M2 of the secondary side winding should be led out from the 2nd turn. As Figure 3 shown, in the top view of the primary side winding coil, the number of turns of the coil surrounded by the middle leg is k1 = 4 turns (counted from the side for determining the number of winding turns), and there are 3 turns on the side of the winding lead-out end of the coil. Therefore, the first midpoint terminal M1 of the primary side winding should be led out from the 2nd turn. When the number of turns wound on the middle leg is zero, there is no intermediate tap lead-out terminal for the transformer. It should be understood that the number of turns of the first intermediate winding and the second intermediate winding cannot be 0 at the same time.

[0077] The present disclosure also provides a converter, including:

[0078] The inverter-side circuit is used to convert the input DC voltage into a first AC voltage; the inverter-side circuit includes a first arm and a second arm connected in parallel, the first arm includes a first switch and a second switch connected in series, and the second arm includes a third switch and a fourth switch connected in series;

[0079] The transformer circuit, the primary side of the transformer circuit is connected to the first connection point of the first switch and the second switch, and the second connection point of the third switch and the fourth switch, and is used to convert the first AC voltage into a second AC voltage;

[0080] The rectifier-side circuit is connected to the secondary side of the transformer circuit and is used to convert the second AC voltage into an output DC voltage;

[0081] Wherein, the transformer circuit includes a transformer according to an embodiment of the present disclosure.

[0082] Specifically, in a traditional converter, once the transformer turns ratio is fixed, the voltage ratio of the primary side winding and the secondary side winding of the transformer is a fixed value, and the voltage regulation range of the converter is thus limited. In the converter according to an embodiment of the present disclosure, a transformer with variable equivalent turns of the primary side winding and the secondary side winding is adopted, which can realize the adjustment of the equivalent turns ratio of the transformer in the converter, thereby expanding the voltage regulation range of the converter and improving the efficiency of voltage conversion.

[0083] See Figure 6 , Figure 6 shows a schematic diagram of a converter according to an embodiment of the present disclosure. Figure 6 In, the inverter-side circuit of the converter is connected to port 1 and receives the input DC voltage from port 1. The inverter-side circuit includes a first arm and a second arm connected in parallel. The first arm includes a first switch Q1 and a second switch Q2 connected in series, and the second arm includes a third switch Q3 and a fourth switch Q4 connected in series. The first connection point A of the first switch Q1 and the second switch Q2 is connected to the first terminal A1 of the primary side of the transformer circuit, and the second connection point B of the third switch Q3 and the fourth switch Q4 is connected to the second terminal B1 of the primary side of the transformer circuit. The inverter-side circuit converts the input DC voltage into a first AC voltage and outputs it to the rectifier-side circuit after being converted into a second AC voltage via the transformer circuit. The rectifier-side circuit includes a third arm and a fourth arm connected in parallel. The third arm includes a fifth switch Q5 and a sixth switch Q6 connected in series, and the fourth arm includes a seventh switch Q7 and an eighth switch Q8 connected in series.

[0084] In some embodiments, the inverter-side circuit further includes a first capacitor arm, connected in parallel with the first arm and the second arm, and includes a first capacitor and a second capacitor connected in series;

[0085] The first terminal of the transformer is connected to a first connection point via a first impedance circuit, the second terminal of the transformer is connected to a second connection point via a second impedance circuit, and the first intermediate terminal of the transformer is connected to a first capacitor connection point of the first capacitor and the second capacitor via a first intermediate impedance circuit.

[0086] Wherein, as Figure 6 shown, the first impedance circuit X1, the second impedance circuit X2, and the first intermediate impedance circuit X5 may include a series and / or parallel structure of at least one of a capacitor or an inductor. The first impedance circuit X1 and the second impedance circuit X2 may be resonant circuits. The series-connected first capacitor C1 and second capacitor C2 are connected in parallel with the first arm and the second arm.

[0087] In some embodiments, the rectifier side circuit includes a third arm and a fourth arm connected in parallel. The third arm includes a fifth switch and a sixth switch connected in series, and the fourth arm includes a seventh switch and an eighth switch connected in series;

[0088] The rectifier side circuit further includes a second capacitor arm, connected in parallel with the third arm and the fourth arm, and including a third capacitor and a fourth capacitor connected in series;

[0089] The third terminal of the transformer is connected to a third connection point of the fifth switch and the sixth switch via a third impedance circuit, the fourth terminal of the transformer is connected to a fourth connection point of the seventh switch and the eighth switch via a fourth impedance circuit, and the second intermediate terminal of the transformer is connected to a second capacitor connection point of the third capacitor and the fourth capacitor via a second intermediate impedance circuit.

[0090] Wherein, the third impedance circuit X3, the fourth impedance circuit X4, and the second intermediate impedance circuit X6 may include a series and / or parallel structure of at least one of a capacitor or an inductor. The converter may further include at least one of a fifth impedance circuit X7 connected between the first terminal A1 and the first intermediate terminal M1, a sixth impedance circuit X8 connected between the second terminal B1 and the first intermediate terminal M1, a seventh impedance circuit X10 connected between the third terminal A2 and the second intermediate terminal M2, and an eighth impedance circuit X9 connected between the fourth terminal B2 and the second intermediate terminal M2. It should be understood that the fifth impedance circuit X7, the sixth impedance circuit X8, the seventh impedance circuit X9, and the eighth impedance circuit X10 may all include a series and / or parallel structure of at least one of a capacitor or an inductor. The output terminal of the rectifier side circuit may be connected to port 2 for supplying power to a load.

[0091] Figure 6In the [device], the inverter side may include four switching transistors Q1 to Q4 and a capacitor bridge arm group C1, C2. The rectifier side may include four diodes Q5 to Q8 (which may also be replaced with switching transistors) and a filter capacitor bridge arm group C3, C4. The transformer circuit part may include impedance branches (X1 to X10) and a transformer. Among them, X1 to X10 may be composed of capacitors, inductors, or series-parallel branches of capacitors and inductors. X1 to X6 can be short-circuited but not open-circuited. X7 to X10 can be open-circuited but not short-circuited. The parameters of X1 and X2 can be the same, the parameters of X3 and X4 can be the same, the parameters of X7 and X8 can be the same, and the parameters of X9 and X10 can be the same.

[0092] The present disclosure also provides a control method for a converter based on the embodiments of the present disclosure, including:

[0093] Controlling the relative phase-shift time between the first bridge arm and the second bridge arm to adjust the equivalent winding turns ratio of the transformer.

[0094] Among them, the relative phase-shift time may refer to the time length corresponding to the phase difference between the conduction moments of the switching devices of the first bridge arm and the second bridge arm. By controlling this time length, the adjustment of the equivalent winding turns ratio of the transformer can be achieved. Refer to Figure 7 , Figure 7 shows the pulse timing diagram of the inverter-side switches according to the embodiments of the present disclosure. Figure 7 In [the diagram], Ts represents the switching period, and Vgs1 to Vgs4 respectively represent the drive pulses of the switching transistors Q1 to Q4. T delay represents the relative phase-shift time between the Q1, Q2 bridge arm and the Q3, Q4 bridge arm.

[0095] In some embodiments, controlling the relative phase-shift time between the first bridge arm and the second bridge arm to adjust the equivalent winding turns ratio of the transformer includes:

[0096] Controlling the first switch of the first bridge arm and the third switch of the second bridge arm to conduct and turn off synchronously, and the second switch of the first bridge arm and the fourth switch of the second bridge arm to conduct and turn off synchronously. The primary side of the transformer is in the in-phase operation mode, and the equivalent winding turns ratio of the transformer is the ratio of the first turns n1 to the third turns n2, n1 / n2; wherein, in the in-phase operation mode, the primary side current flows into from the first terminal and the second terminal simultaneously and flows out from the first intermediate terminal; or flows into from the first intermediate terminal and flows out from the first terminal and the second terminal simultaneously.

[0097] Specifically, when T delay = 0, Q1 and Q3 switch simultaneously, Q2 and Q4 switch simultaneously, and the state of the converter is that the primary side bridge arm is in the in-phase operation mode, Figure 6The midpoints A and B of the bridge arms shown are equivalent to the same point. At this time, the current on the primary side flows into the A1 and B1 terminals of the transformer simultaneously and flows out from the M1 terminal; or flows out from the A1 and B1 terminals of the transformer simultaneously and flows into the M1 terminal, as Figure 8 shown. Figure 8 Fig. shows a schematic diagram of the primary side of the transformer operating in the in-phase mode according to an embodiment of the present disclosure. In this case, since there is no closed current loop surrounding the middle column of the transformer, no magnetic flux is generated. The magnetic flux of the transformer is only generated by the side columns 1 and 2, enabling energy exchange between the primary and secondary windings. At this time, the equivalent turns ratio of the transformer only depends on the number of turns wound around the side columns of the magnetic core, and the equivalent turns ratio of the transformer is |n1 / n2|. The equivalent circuit of the transformer when the primary side of the transformer is in the in-phase operating mode is as Figure 9 shown.

[0098] In some embodiments, controlling the relative phase-shifting time of the first bridge arm and the second bridge arm to adjust the equivalent winding turns ratio of the transformer includes:

[0099] Controlling the first switch of the first bridge arm and the fourth switch of the second bridge arm to conduct and turn off synchronously, and the second switch of the first bridge arm and the third switch of the second bridge arm to conduct and turn off synchronously. The primary side of the transformer is in the anti-phase operating mode; in the anti-phase operating mode, the primary side current flows in from the first terminal and out from the second terminal.

[0100] Specifically, when the phase-shifting time T delay between the first bridge arm and the second bridge arm = Ts / 2, the switching tubes Q1 and Q4 switch simultaneously, and Q2 and Q3 switch simultaneously. At this time, the primary side bridge arm of the converter is in the anti-phase operating mode, as Figure 10 shown. Figure 10 Fig. shows a schematic diagram of the primary side of the transformer operating in the anti-phase mode according to an embodiment of the present disclosure, Figure 11 Fig. shows the equivalent circuit of the transformer when the primary side of the transformer is in the anti-phase operating mode. Assuming that the first impedance circuit and the second impedance circuit are two resonant tanks with the same parameters, there will be no current flowing out from M1 or flowing into the C1 and C2 capacitor bridge arms, nor will there be current flowing out from M2 or flowing into the C3 and C4 capacitor bridge arms. In this case, closed current loops will surround both the side columns and the middle column of the transformer, so magnetic fluxes will be generated in both, enabling energy exchange between the primary and secondary windings. At this time, the equivalent turns ratio of the transformer depends on the number of turns of the windings wound around the side columns and the middle column, as well as the winding directions.

[0101] In some embodiments, when both the first winding and the second winding are wound in a direction opposite to that of the first intermediate winding, and both the third winding and the fourth winding are wound in a direction opposite to that of the second intermediate winding, the ratio of the equivalent winding turns of the transformer is |(n1 + k1) / (n2 + k2)|. Specifically, when the center leg and the side legs of the primary winding are designed with opposite winding directions, and at the same time the center leg and the side legs of the secondary winding are also designed with opposite winding directions, the equivalent turn ratio of the transformer is |(n1 + k1) / (n2 + k2)|.

[0102] In some embodiments, when both the first winding and the second winding are wound in a direction opposite to that of the first intermediate winding, and both the third winding and the fourth winding are wound in a direction the same as that of the second intermediate winding, the ratio of the equivalent winding turns of the transformer is |(n1 + k1) / (n2 - k2)|. Specifically, when the center leg and the side legs of the primary winding are designed with opposite winding directions, and at the same time the center leg and the side legs of the secondary winding are designed with the same winding direction, the equivalent turn ratio of the transformer is |(n1 + k1) / (n2 - k2)|.

[0103] In some embodiments, when both the first winding and the second winding are wound in a direction the same as that of the first intermediate winding, and both the third winding and the fourth winding are wound in a direction opposite to that of the second intermediate winding, the ratio of the equivalent winding turns of the transformer is |(n1 - k1) / (n2 + k2)|. Specifically, when the center leg and the side legs of the primary winding are designed with the same winding direction, and at the same time the center leg and the side legs of the secondary winding are designed with opposite winding directions, the equivalent turn ratio of the transformer is |(n1 - k1) / (n2 + k2)|.

[0104] In some embodiments, when both the first winding and the second winding are wound in a direction the same as that of the first intermediate winding, and both the third winding and the fourth winding are wound in a direction the same as that of the second intermediate winding, the ratio of the equivalent winding turns of the transformer is |(n1 - k1) / (n2 - k2)|. Specifically, when the center leg and the side legs of the primary winding are designed with the same winding direction, and at the same time the center leg and the side legs of the secondary winding are also designed with the same winding direction, the equivalent turn ratio of the transformer is |(n1 - k1) / (n2 - k2)|.

[0105] In some embodiments, controlling the relative phase shift time of the first bridge arm and the second bridge arm to adjust the ratio of the equivalent winding turns of the transformer includes:

[0106] Control the relative phase-shifting time between the first bridge arm and the second bridge arm to vary within (0, Ts / 2), so that the equivalent winding turns ratio of the transformer varies with the different phase-shifting times.

[0107] It can be seen that, according to the control method of the converter in the embodiments of the present disclosure, by adjusting the phases of the Q1 and Q2 bridge arms and the Q3 and Q4 bridge arms, the effect of adjusting the equivalent turns ratio of the transformer can be achieved, thereby expanding the voltage regulation range of the transformer, realizing the regulation of a wide voltage range, and improving the voltage conversion efficiency.

[0108] Those of ordinary skill in the art should understand that: the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the present disclosure (including the claims) is limited to these examples; under the concept of the present disclosure, the technical features between the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations in different aspects of the embodiments of the present disclosure as described above, and they are not provided in detail for the sake of brevity.

[0109] In addition, for the sake of simplicity of description and discussion, and in order not to make the embodiments of the present disclosure difficult to understand, the well-known power / ground connections to integrated circuit (IC) chips and other components may or may not be shown in the provided drawings. In addition, the device may be shown in the form of a block diagram in order not to make the embodiments of the present disclosure difficult to understand, and this also takes into account the fact that the details of the implementation manner of these block diagram devices are highly dependent on the platform on which the embodiments of the present disclosure are to be implemented (that is, these details should be completely within the understanding scope of those skilled in the art). In the case of elaborating specific details (such as circuits) to describe the exemplary embodiments of the present disclosure, it is obvious to those skilled in the art that the embodiments of the present disclosure can be implemented without these specific details or with variations of these specific details. Therefore, these descriptions should be considered illustrative rather than restrictive.

[0110] Although the present disclosure has been described in conjunction with specific embodiments of the present disclosure, many alternatives, modifications, and variations of these embodiments will be apparent to those of ordinary skill in the art based on the foregoing description. For example, other memory architectures (such as dynamic RAM (DRAM)) can be used in the discussed embodiments.

[0111] The embodiments of the present disclosure are intended to cover all such alternatives, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the embodiments of the present disclosure shall be included within the protection scope of the present disclosure.

Claims

1. A transformer, characterized in that: include: A magnetic core, comprising a first side column, a middle column and a second side column, for providing a magnetic circuit; A first winding disposed on the first side column, wherein the first winding is provided with a first terminal; A second winding disposed on the second side column, the second winding being provided with a second terminal; the number of turns of the first winding and the second winding are both a first number of turns n1; A first intermediate winding is arranged on the center column, the first intermediate winding is provided with a first intermediate terminal; the first terminal, the second terminal and the first intermediate terminal are arranged on the same side of the magnetic core, the number of turns of the first intermediate winding is a second number of turns k1; the first number of turns n1 is a positive integer, and the second number of turns k1 is a non-negative integer; A third winding disposed on the first side column, wherein the third winding is provided with a third terminal; a fourth winding disposed on the second side column, the fourth winding being provided with a fourth terminal; the number of turns of the third winding and the fourth winding are both the third number of turns n2; A second intermediate winding is arranged on the center column, and the second intermediate winding is provided with a second intermediate terminal; the third terminal, the fourth terminal and the second intermediate terminal are arranged on the same side of the magnetic core, and the number of turns of the second intermediate winding is a fourth number of turns k2; the third number of turns n2 is a positive integer, and the fourth number of turns k2 is a non-negative integer; The first winding and the second winding have different relative relationships with the first intermediate winding in terms of winding direction, so that the transformer presents different primary side equivalent winding turns in the circuit; The third winding and the fourth winding have different relative relationships with the second intermediate winding in terms of winding direction, so that the transformer presents different secondary side equivalent winding turns in the circuit.

2. The transformer according to claim 1, characterized in that When both the first winding and the second winding are wound in opposite directions to the first intermediate winding, the number of turns of the primary side equivalent winding of the transformer is the first number of turns n1, or the sum n1+k1 of the first number of turns n1 and the second number of turns k1; or, When both the first winding and the second winding are wound in the same direction as the first intermediate winding, the number of turns of the primary side equivalent winding of the transformer is the first number of turns n1, or the absolute value |n1-k1| of the difference between the first number of turns n1 and the second number of turns k1.

3. The transformer according to claim 1, characterized in that When the third winding and the fourth winding are both wound in opposite directions to the second intermediate winding, the number of turns of the secondary equivalent winding of the transformer is the third number of turns n2, or the sum of the third number of turns n2 and the fourth number of turns k2, n2+k2; or, When both the third winding and the fourth winding are wound in the same direction as the second intermediate winding, the number of turns of the secondary equivalent winding of the transformer is the third number of turns n2, or the absolute value |n2-k2| of the difference between the third number of turns n2 and the fourth number of turns k2.

4. A converter, characterized in that: include: An inverter side circuit, used for converting an input DC voltage into a first AC voltage; the inverter side circuit comprises a first bridge arm and a second bridge arm connected in parallel, the first bridge arm comprises a first switch and a second switch connected in series, and the second bridge arm comprises a third switch and a fourth switch connected in series; a transformer circuit, wherein a primary side of the transformer circuit is connected to a first connection point between the first switch and the second switch, and a second connection point between the third switch and the fourth switch, and is used to convert the first AC voltage into a second AC voltage; a rectifier-side circuit, connected to the secondary side of the transformer circuit, and configured to convert the second AC voltage into an output DC voltage; Wherein, the transformer circuit comprises a transformer according to any one of claims 1-3.

5. The converter according to claim 4, characterized in that The inverter side circuit also includes a first capacitor bridge arm connected in parallel with the first bridge arm and the second bridge arm, including a first capacitor and a second capacitor connected in series; The first terminal of the transformer is connected to a first connection point via a first impedance circuit, the second terminal of the transformer is connected to a second connection point via a second impedance circuit, and the first intermediate terminal of the transformer is connected to a first capacitor connection point of the first capacitor and the second capacitor via a first intermediate impedance circuit.

6. The converter according to claim 4, characterized in that The rectifier side circuit comprises a third bridge arm and a fourth bridge arm connected in parallel, the third bridge arm comprises a fifth switch and a sixth switch connected in series, and the fourth bridge arm comprises a seventh switch and an eighth switch connected in series; The rectifier side circuit also includes a second capacitor bridge arm, which is connected in parallel with the third bridge arm and the fourth bridge arm, and includes a third capacitor and a fourth capacitor connected in series; The third terminal of the transformer is connected to a third connection point of the fifth switch and the sixth switch via a third impedance circuit, the fourth terminal of the transformer is connected to a fourth connection point of the seventh switch and the eighth switch via a fourth impedance circuit, and the second intermediate terminal of the transformer is connected to a second capacitor connection point of the third capacitor and the fourth capacitor via a second intermediate impedance circuit.

7. A control method for a converter according to any one of claims 4 to 6, characterized in that: include: The relative phase shift time between the first bridge arm and the second bridge arm is controlled to adjust the ratio of the equivalent winding turns of the transformer.

8. The method according to claim 7, characterized in that Controlling the relative phase shift time of the first bridge arm and the second bridge arm to adjust the ratio of the equivalent winding turns of the transformer includes: The first switch of the first bridge arm and the third switch of the second bridge arm are controlled to be turned on and off synchronously, and the second switch of the first bridge arm and the fourth switch of the second bridge arm are controlled to be turned on and off synchronously, the primary side of the transformer is in a co-phase operation mode, and the ratio of the equivalent winding turns of the transformer is the ratio n1 / n2 of the first number of turns n1 to the third number of turns n2; wherein, in the co-phase operation mode, the primary side current flows into the first terminal and the second terminal at the same time and flows out from the first intermediate terminal; or flows into the first intermediate terminal and flows out from the first terminal and the second terminal at the same time.

9. The method according to claim 7, characterized in that: Controlling the relative phase shift time of the first bridge arm and the second bridge arm to adjust the ratio of the equivalent winding turns of the transformer includes: Controlling the first switch of the first bridge arm and the fourth switch of the second bridge arm to be turned on and off synchronously, and controlling the second switch of the first bridge arm and the third switch of the second bridge arm to be turned on and off synchronously, and the primary side of the transformer is in an anti-phase operation mode; in the anti-phase operation mode, the primary side current flows into the first terminal and flows out of the second terminal, or flows into the second terminal and flows out of the first terminal; Wherein, when the first winding and the second winding are both wound in opposite directions to the first intermediate winding, and the third winding and the fourth winding are both wound in opposite directions to the second intermediate winding, the ratio of the number of equivalent winding turns of the transformer is |(n1+k1) / (n2+k2)|; Alternatively, when the first winding and the second winding are both wound in opposite directions to the first intermediate winding, and the third winding and the fourth winding are both wound in the same direction as the second intermediate winding, the ratio of the number of turns of the equivalent winding of the transformer is |(n1+k1) / (n2-k2)|; Alternatively, when the first winding and the second winding are both wound in the same direction as the first intermediate winding, and the third winding and the fourth winding are both wound in the opposite direction to the second intermediate winding, the ratio of the number of turns of the equivalent winding of the transformer is |(n1-k1) / (n2+k2)|; Alternatively, when the first winding and the second winding are both wound in the same direction as the first intermediate winding, and the third winding and the fourth winding are both wound in the same direction as the second intermediate winding, the ratio of the equivalent winding turns of the transformer is |(n1-k1) / (n2-k2)|.

10. The method according to claim 7, characterized in that Controlling the relative phase shift time of the first bridge arm and the second bridge arm to adjust the ratio of the equivalent winding turns of the transformer includes: The relative phase shift time of the first bridge arm and the second bridge arm is controlled to vary between (0, Ts / 2), so that the ratio of the equivalent winding turns of the transformer varies with the phase shift time; wherein Ts represents the switching period.

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