Conversion circuit based on magnetic coupling double BUCK and single-stage isolation PFC and device thereof
By using a magnetically coupled dual-buck converter circuit with single-stage isolation PFC, the problems of large output current ripple, high component loss, large size, high cost, and low conversion efficiency are solved, achieving efficient voltage-to-current conversion and charging/discharging management of the DC output port.
Patent Information
- Application Number
- CN202520230594.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-13
- Publication Date
- 2026-02-24
- Estimated Expiration
- 2035-02-13
AI Technical Summary
In existing technologies, battery charging and discharging management and load power supply processes suffer from problems such as large output current ripple, high component losses, large size, high cost, and low conversion efficiency.
A converter circuit based on magnetically coupled double BUCK and single-stage isolation PFC is adopted, including a rectifier circuit and a transformer circuit. The rectifier circuit is equipped with an isolation circuit to form a single-stage isolation PFC circuit. The transformer circuit forms a multi-channel magnetically coupled inductor through multiple coil magnetic circuit coupling. The coils act on different branches to form multiple BUCK circuits. The voltage and current are controlled by controlling the on and off time of the switch group.
It improves voltage-to-current conversion efficiency, reduces magnetic material loss, lowers costs, and enables charge and discharge management of the DC output port.
Smart Images
Figure CN223942583U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of power electronics technology, and more specifically, to a converter circuit and device based on magnetically coupled double BUCK and single-stage isolated PFC. Background Technology
[0002] With the increasing demand for energy conservation, emission reduction, and air pollution control, new energy storage systems, new energy engineering vehicles, and electric vehicles have been widely promoted and applied in the market. In contrast, many existing technologies achieve battery charging and discharging management or load power supply through two-stage circuit conversion. That is, the AC mains power is first rectified by a PFC circuit, and then the voltage and current are regulated by an isolated DC-DC converter circuit, or a single-channel BUCK circuit is used to manage battery charging and discharging or supply power to the load through a second DC port. These technologies suffer from drawbacks such as large output current ripple, large component losses, large size, high cost, and low conversion efficiency.
[0003] Therefore, the industry urgently needs to develop a converter circuit based on magnetically coupled dual-buck and single-stage isolated PFC, which has both PFC rectification function and isolation regulation of voltage and current, in order to improve the problems of large output current ripple, large component loss, large size, high cost and low conversion efficiency caused by traditional technology. Utility Model Content
[0004] The technical problems to be solved by this utility model are large output current ripple, large component loss, large size, high cost and low conversion efficiency. In view of the above-mentioned defects of the prior art, a conversion circuit and control method based on magnetic coupling double BUCK and single-stage isolation PFC are provided.
[0005] The technical solution adopted by this utility model to solve its technical problem is:
[0006] A converter circuit based on magnetically coupled double BUCK and single-stage isolation PFC is constructed, comprising a rectifier circuit and a transformer circuit. The rectifier circuit includes an isolation circuit for providing electrical isolation, thereby enabling the rectifier circuit to form a single-stage isolation PFC circuit.
[0007] The transformer circuit includes multiple coils, and the coils are magnetically coupled to each other. The coils are located on the second inductor of the transformer circuit so that the second inductor forms a multi-channel magnetically coupled inductor. The coils act on different branches of the transformer circuit to form multiple BUCK circuits.
[0008] The transformer circuit is electrically connected to the rectifier circuit through the isolation circuit;
[0009] The external ports of the rectifier circuit and the transformer circuit include one AC port and multiple DC ports, and the external ports are used to connect to a power supply or a load.
[0010] Furthermore, the rectifier circuit also includes a first regulating circuit and a second regulating circuit, which are connected through the isolation circuit.
[0011] Furthermore, the isolation circuit includes a first capacitor, a first inductor, a second capacitor, and a three-winding transformer. The three-winding transformer includes a first winding, a second winding, and a third winding. The first capacitor, the first inductor, and the first winding are connected in series and connected to the first regulating circuit. The second capacitor and the second winding are connected in series and connected to the second regulating circuit. The third winding is connected to the transformer circuit.
[0012] In the isolation circuit, the first inductor and the three-winding transformer either have the same magnetic core or each have different magnetic cores.
[0013] Furthermore, the first regulating circuit includes multiple switch groups, each of which includes multiple switching transistors, which are arranged in combination to enable bidirectional control of the switch groups.
[0014] Furthermore, the first regulating circuit includes a first switch, a second switch, a third switch, a fourth switch, a fifth switch, a sixth switch, a seventh switch, an eighth switch, and a primary capacitor. The first switch and the second switch form a first switch group, the third switch and the fourth switch form a second switch group, the fifth switch and the sixth switch form a third switch group, and the seventh switch and the eighth switch form a fourth switch group. The first switch group and the third switch group constitute a first bridge arm, and the second switch group and the fourth switch group constitute a second bridge arm. The primary capacitor, the first bridge arm, and the second bridge arm are connected in parallel.
[0015] The on / off times in the switch group correspond to the positive and negative periods of the input waveform of the AC port.
[0016] Furthermore, the second regulating circuit includes a ninth switch, a tenth switch, an eleventh switch, a twelfth switch, and a third capacitor. The ninth switch and the eleventh switch form a third bridge arm, and the tenth switch and the twelfth switch form a fourth bridge arm. The third bridge arm, the fourth bridge arm, and the third capacitor are connected in parallel. The on and off times of the ninth switch and the eleventh switch are opposite, and the on and off times of the tenth switch and the twelfth switch are opposite.
[0017] Furthermore, the coil includes a first coil and a second coil; the transformer circuit also includes a thirteenth switch, a fourteenth switch, a fifteenth switch, a sixteenth switch and a fourth capacitor. The thirteenth switch, the fifteenth switch and the first coil of the multi-channel magnetically coupled inductor form a first BUCK branch, and the fourteenth switch, the sixteenth switch and the second coil of the multi-channel magnetically coupled inductor form a second BUCK branch. The first BUCK branch and the second BUCK branch are connected in parallel and interleaved, and share the fourth capacitor.
[0018] There is a region where the on and off times of the thirteenth switch and the fifteenth switch are partially opposite, and there is a region where the on and off times of the fourteenth switch and the sixteenth switch are partially opposite, and the thirteenth switch and the fourteenth switch form a phase difference of 0 to 180 degrees.
[0019] This utility model also provides a device based on a magnetically coupled dual-buck and single-stage isolated PFC conversion circuit, including a rectifier module, a transformer module, and a controller. The rectifier module includes a first regulating module, a second regulating module, and an isolation module. The isolation module is used to connect the first regulating module, the second regulating module, and the transformer module to form electrical isolation. The external ports of the first regulating module, the second regulating module, and the transformer module include one AC port and multiple DC ports, and the external ports are used to connect a power supply or a load.
[0020] The transformer module includes a multi-channel magnetically coupled inductor, which includes a first coil, a second coil, a non-shared magnetic core, and a shared magnetic core. The non-shared magnetic core is located outside the second coil of the first coil and tightly surrounds the first coil and the second coil. The shared magnetic core is located between the first coil and the second coil so that the first coil and the second coil form a magnetic circuit coupling.
[0021] The controller includes a data acquisition module, an analysis module, a judgment module, and a control module. The analysis module and the judgment module are electrically connected to the data acquisition module and the control module, respectively. The controller controls the on / off state of each switch in the first adjustment module, the second adjustment module, and the transformer module to control the magnitude and direction of the output voltage and current of the conversion circuit.
[0022] The beneficial effects of this utility model are as follows:
[0023] This utility model relates to a converter circuit and device based on magnetically coupled dual-bucket and single-stage isolated PFC, including a rectifier circuit, a transformer circuit, and a controller. The external ports include one AC port and multiple DC ports for connecting to a power supply or load. The rectifier circuit includes a first regulating circuit, a second regulating circuit, and an isolation circuit. The isolation circuit provides electrical isolation. The transformer circuit includes a dual-channel magnetically coupled inductor formed by the magnetic coupling of a first coil and a second coil, creating an interleaved parallel dual-bucket circuit. The controller controls the converter circuit to output the target voltage and current. This utility model uses a dual-channel magnetically coupled inductor to form two bucket circuits, effectively improving voltage-to-current conversion efficiency, reducing magnetic material losses, and lowering costs. This utility model combines a single-stage isolated PFC rectifier circuit with a dual-bucket DC-DC converter circuit to form a three-port bidirectional converter circuit, directly powered by AC mains, enabling charging and discharging management of the DC output port. Attached Figure Description
[0024] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the utility model will be further described below in conjunction with the accompanying drawings and embodiments. The drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0025] Figure 1 This is a conversion circuit based on magnetically coupled dual-buck and single-stage isolated PFC in one embodiment of the present invention;
[0026] Figure 2 This is a control circuit diagram of a converter circuit based on magnetically coupled dual-buck and single-stage isolated PFC in one embodiment of this utility model;
[0027] Figure 3 This is a simulation waveform diagram of the voltage and current of the AC port changing over time in one embodiment of this utility model;
[0028] Figure 4 This is a timing diagram of the controller's control of each control switch when the AC port is used as the input and the first DC port and the second DC port are used as the output ports, and the AC input is in the positive half-cycle.
[0029] Figure 5 This is a timing diagram of the controller's control of each control switch when the AC port is used as the input and the first DC port and the second DC port are used as the output ports in one embodiment of this utility model, and the AC input is in the negative half-cycle.
[0030] Figure 6This is a simulation waveform diagram of the voltage change over time of the first, second, and third windings of a three-winding transformer in one embodiment of this utility model;
[0031] Figure 7 This is a simulation waveform diagram of the current of the first inductor changing with time in one embodiment of this utility model;
[0032] Figure 8 This is a simulation waveform diagram showing the change of current in the first inductor over time in one embodiment of this utility model;
[0033] Figure 9 This is a simulation waveform diagram of the output current of the first DC port changing with time in one embodiment of this utility model;
[0034] Figure 10 This is a simulation waveform diagram of the current change over time of a dual-channel magnetically coupled inductor in one embodiment of this utility model;
[0035] Figure 11 This is a simulation waveform diagram of the output current of the second DC port changing with time in one embodiment of this utility model;
[0036] Figure 12 This is a structural diagram of a device based on a magnetically coupled dual-buck and single-stage isolated PFC conversion circuit in one embodiment of the present invention.
[0037] Figure 13 This is a perspective view of a dual-channel magnetically coupled inductor in one embodiment of this utility model;
[0038] Figure 14 This is an exploded view of a dual-channel magnetically coupled inductor in one embodiment of this utility model;
[0039] Figure 15 This is a magnetic simulation diagram of a dual-channel magnetically coupled inductor in one embodiment of this utility model.
[0040] Label Explanation: Q1, First Switch; Q2, Second Switch; Q3, Third Switch; Q4, Fourth Switch; Q5, Fifth Switch; Q6, Sixth Switch; Q7, Seventh Switch; Q8, Eighth Switch; Q9, Ninth Switch; Q10, Tenth Switch; Q11, Eleventh Switch; Q12, Twelfth Switch; Q13, Thirteenth Switch; Q14, Fourteenth Switch; Q15, Fifteenth Switch; Q16, Sixteenth Switch; C0, Primary Capacitor; L1, First Inductor; C1, First Capacitor; C2, Second Capacitor; C3, Third Capacitor; L2, Dual-Channel Magnetic Coupled Inductor; L 2_W1, First coil; L2_W2, Second coil; C4, Fourth capacitor; T1, Three-winding transformer; T1_W1, First winding; T1_W2, Second winding; T1_W3, Third winding; Vac1, AC port; Vdc1, First DC port; Vdc2, Second DC port; 10, First regulating module; 20, Second regulating module; 30, Transformer module; 40, Controller; 401, Acquisition module; 402, Analysis module; 403, Control module; 404, Judgment module; 50, Isolation module; 1, Common core; 2, Non-common core. Detailed Implementation
[0041] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.
[0042] Please refer to the attached document. Figures 1-15 This invention proposes a converter circuit based on magnetically coupled double-buckle and single-stage isolated PFC, including a rectifier circuit and a transformer circuit. The rectifier circuit includes an isolation circuit to provide electrical isolation, enabling the rectifier circuit to form a single-stage isolated PFC circuit. The transformer circuit includes multiple coils, which are magnetically coupled. The coils are located on the second inductor of the transformer circuit, making the second inductor a multi-channel magnetically coupled inductor. The coils act on different branches of the transformer circuit to form multiple buckle circuits. The transformer circuit is electrically connected to the rectifier circuit through the isolation circuit. The external ports of the rectifier circuit and the transformer circuit include one AC port Vac1 and multiple DC ports, which are used to connect to a power supply or load.
[0043] In this embodiment, the converter circuit based on magnetically coupled dual-bucket and single-stage isolated PFC includes a rectifier circuit and a transformer circuit. The rectifier circuit includes a first regulating circuit, a second regulating circuit, and an isolation circuit. The external ports of the rectifier circuit and the transformer circuit include one AC port Vac1 and multiple DC ports. The external ports are used to connect to a power supply or a load. One external port is arbitrarily selected to connect to the power supply, and the other two external ports are connected to the load, forming a three-port bidirectional output circuit. In a specific embodiment, the case where the external port of the first regulating circuit is the AC port Vac1 and is connected to the power supply, and the external ports of the second regulating circuit and the transformer circuit are DC ports and are connected to the load, is discussed. The first regulating circuit includes multiple switch groups, each switch group including multiple switching transistors. The switching transistors are arranged and combined to allow bidirectional control of the switch group. Specifically, the first regulating circuit includes a first switch Q1, a second switch Q2, a third switch Q3, a fourth switch Q4, a fifth switch Q5, a sixth switch Q6, a seventh switch Q7, an eighth switch Q8, and a primary capacitor C0. The first switch Q1 and the second switch Q2 form the first switch group. The third switch Q3 and the fourth switch Q4 form the second switch group, the fifth switch Q5 and the sixth switch Q6 form the third switch group, and the seventh switch Q7 and the eighth switch Q8 form the fourth switch group. The first switch group and the third switch group form the first bridge arm, and the second switch group and the fourth switch group form the second bridge arm. The primary capacitor C0, the first bridge arm, and the second bridge arm are connected in parallel. The on and off times in the switch groups correspond to the positive and negative periods of the input waveform at the AC port Vac1. The second regulating circuit includes the ninth switch Q9, the tenth switch Q10, the eleventh switch Q11, and the twelfth switch Q12. Switch Q12 and the third capacitor C3, the ninth switch Q9 and the eleventh switch Q11 form the third bridge arm, and the tenth switch Q10 and the twelfth switch Q12 form the fourth bridge arm. The third bridge arm, the fourth bridge arm, and the third capacitor C3 are connected in parallel. The on and off times of the ninth switch Q9 and the eleventh switch Q11 are opposite, and the on and off times of the tenth switch Q10 and the twelfth switch Q12 are also opposite. The first regulating circuit and the second regulating circuit are connected through an isolation circuit. The isolation circuit is used to provide electrical isolation so that the rectifier circuit forms a single-stage isolated PFC circuit. PFC (Power Factor Correction) The factor correction rectifier circuit improves the power factor by reducing the harmonic distortion of the input current, making the output current waveform closer to a sine wave. The transformer circuit includes multiple coils with magnetic coupling between them. The coils are located on the second inductor of the transformer circuit, so that the second inductor forms a multi-channel magnetically coupled inductor. The coils act on different branches of the transformer circuit to form multiple BUCK circuits. In a specific embodiment, the coils include a first coil L2_W1 and a second coil L2_W2, and the multi-channel magnetically coupled inductor is a dual-channel magnetically coupled inductor L2.The transformer circuit also includes a thirteenth switch Q13, a fourteenth switch Q14, a fifteenth switch Q15, a sixteenth switch Q16, and a fourth capacitor C4. The thirteenth switch Q13, the fifteenth switch Q15, and the first coil L2_W1 form the first BUCK branch. The fourteenth switch Q14, the sixteenth switch Q16, and the second coil L2_W2 form the second BUCK branch. The first and second BUCK branches are connected in parallel and interleaved, sharing the fourth capacitor C4. There is a region between the thirteenth switch Q13 and the fifteenth switch Q15 where the on and off times are opposite. The fourteenth switch Q14 and the sixteenth switch Q16... There is a region where the on / off times are partially opposite, and the thirteenth switch Q13 and the fourteenth switch Q14 form a phase difference of 0 to 180 degrees; the transformer circuit is electrically connected to the rectifier circuit through an isolation circuit. Based on the magnitude and direction of the current and voltage in the isolation circuit, the on / off times of the thirteenth switch Q13, the fourteenth switch Q14, the fifteenth switch Q15, and the sixteenth switch Q16 are controlled to achieve control over the magnitude and direction of the output voltage and current at the external port of the transformer circuit; in a specific embodiment, the switches included in the conversion circuit can be made of SiC (silicon carbide), GaN (gallium nitride), or IGBT (Insulated-Gate) semiconductor materials. Semiconductor switches include Bipolar Transistors (IGBTs) and MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors); the first inductor L1 is a resonant inductor used to store and transfer energy; the primary capacitor C0 and the third capacitor C3 are high-frequency filter capacitors used to filter out high-frequency noise and interference, ensuring circuit stability and signal quality; the first capacitor C1 and the second capacitor C2 are both DC blocking capacitors, used to block DC signals while allowing AC signals to pass through. The fourth capacitor C4 is an energy storage filter capacitor used to store energy and filter out noise and interference.
[0044] This invention proposes the use of a dual-channel magnetically coupled inductor L2, which includes a first coil L2_W1 and a second coil L2_W2. A common magnetic core 1 is provided between the first coil L2_W1 and the second coil L2_W2, forming magnetic circuit coupling. The first coil L2_W1 and the second coil L2_W2 act on different branches of the transformer circuit, forming two staggered parallel BUCK circuits, effectively improving voltage-to-current conversion efficiency, reducing magnetic material loss, and lowering costs. This invention also uses a PFC rectifier circuit and a dual-BUCK DC-DC circuit to form a three-port bidirectional converter circuit, directly powered by AC mains, to achieve charging and discharging management of the other two ports.
[0045] Please refer to Figures 1-3The converter circuit based on magnetically coupled dual-buck and single-stage isolation PFC includes a rectifier circuit and a transformer circuit. The rectifier circuit includes a first regulating circuit, a second regulating circuit, and an isolation circuit. The external ports of the rectifier circuit and the transformer circuit include one AC port Vac1 and multiple DC ports. The external ports are used to connect to the power supply or the load. One external port is selected to connect to the power supply, and the other two external ports are connected to the load to form a three-port bidirectional output circuit.
[0046] In specific implementation: the first regulating circuit, the second regulating circuit, and the transformer circuit each include an external port, which includes an AC port Vac1 and multiple DC ports, used to connect to a power supply or a load. One external port is arbitrarily selected to connect to the power supply, and the other two external ports are used to connect to the load. The power supply provides power, and the load consumes power, forming a three-port bidirectional dual-port output circuit. In one specific embodiment, we mainly discuss the case where the external port of the first regulating circuit is the AC port Vac1 and is connected to the power supply, while the external ports of the second regulating circuit and the transformer circuit are DC ports and are connected to the load. In this case, the external port of the first regulating circuit is the AC port Vac1, and the external ports of the second regulating circuit are... The first DC port is Vdc1, the external port of the transformer circuit is the second DC port Vdc2, the AC port Vac1 is connected to the mains power, and the first DC port Vdc1 and the second DC port Vdc2 are connected to the load. Current flows in from the AC port Vac1 and flows out from the first DC port Vdc1 and the second DC port Vdc2 respectively. There is no need to pre-rectify the mains power, and the mains power is directly supplied to realize the charging and discharging management of the other two ports. It can be specifically applied to new energy vehicles. The AC port Vac1 is connected to the mains power to input power to the conversion circuit. The first DC port Vdc1 is used to charge the power battery of the new energy vehicle, and the second DC port Vdc2 is used to supply power to the low-voltage equipment on the vehicle.
[0047] More specifically, such as Figure 3 The figure shows the simulated waveforms of the voltage and current of AC port Vac1 changing over time when AC port Vac1 is used as the input and the first DC port Vdc1 and the second DC port Vdc2 are used as the output ports. The input waveform of AC port Vac1 has a positive half-cycle and a negative half-cycle.
[0048] Please refer to Figure 1 and Figure 2The first and second regulating circuits are connected by an isolation circuit, which provides electrical isolation to enable the rectifier circuit to form a single-stage isolated PFC circuit. The transformer circuit is electrically connected to the rectifier circuit through the isolation circuit. The isolation circuit includes a first capacitor C1, a first inductor L1, a second capacitor C2, and a three-winding transformer T1. The three-winding transformer T1 includes a first winding T1_W1, a second winding T1_W2, and a third winding T1_W3. The first capacitor C1, the first inductor L1, and the first winding T1_W1 are connected in series and connected to the first regulating circuit. The second capacitor C2 and the second winding T1_W2 are connected in series and connected to the second regulating circuit. The third winding T1_W3 is connected to the transformer circuit. In the isolation circuit, the first inductor L1 and the three-winding transformer T1 may have the same magnetic core or may each have different magnetic cores.
[0049] In specific implementation: the isolation circuit includes a first capacitor C1, a first inductor L1, a second capacitor C2, and a three-winding transformer T1. The transformer includes a first winding T1_W1, a second winding T1_W2, and a third winding T1_W3. The first capacitor C1, the first inductor L1, and the first winding T1_W1 are connected in series, with one end connected between the first and third switch groups and the other end connected between the second and fourth switch groups. In one specific embodiment, the series connection order of the first capacitor C1, the first inductor L1, and the first winding T1_W1 is not fixed. The second capacitor C2 and the second winding T1_W2 are connected in series, with one end connected between the ninth switch Q9 and the eleventh switch Q11 and the other end connected between the tenth switch Q10 and the twelfth switch Q12. In one specific embodiment, the series connection order of the second capacitor C2 and the second winding T1_W2 is not fixed. The isolation circuit provides electrical isolation. The first regulating circuit and the second regulating circuit are connected through the isolation circuit to form a single-stage isolated PFC circuit. PFC (Power Controller) The FactorCorrection circuit improves the power factor by reducing harmonic distortion of the input current, making the output current waveform closer to a sine wave. The third winding T1_W3 is connected to the ninth switch Q9 and the tenth switch Q10 respectively. The transformer circuit is electrically connected to the rectifier circuit through the isolation circuit. In the isolation current conversion network circuit, when the first inductor L1 and the three-winding transformer T1 are wound with different magnetic cores, the first inductor L1 and the three-winding transformer T1 are connected in series in a non-magnetic coupling form. When the first inductor L1 and the three-winding transformer T1 are wound with the same magnetic core, the inductance flux of the first inductor L1 is generated by the leakage inductance between the first winding T1_W1 and the second winding T1_W2 in the three-winding transformer T1, that is, the first inductor L1 and the three-winding transformer T1 are connected in series in a magnetic coupling form.
[0050] Please refer to Figures 1-8The first regulating circuit includes multiple switch groups, each switch group including multiple switching transistors, which are arranged in combination to enable bidirectional control of the switch group. The first regulating circuit includes a first switch Q1, a second switch Q2, a third switch Q3, a fourth switch Q4, a fifth switch Q5, a sixth switch Q6, a seventh switch Q7, an eighth switch Q8, and a primary capacitor C0. The first switch Q1 and the second switch Q2 form the first switch group, the third switch Q3 and the fourth switch Q4 form the second switch group, the fifth switch Q5 and the sixth switch Q6 form the third switch group, and the seventh switch Q7 and the eighth switch Q8 form the fourth switch group. The first switch group and the third switch group constitute the first bridge arm, and the second switch group and the fourth switch group constitute the second bridge arm. The primary capacitor C0, the first bridge arm, and the second bridge arm are connected in parallel. The on and off times in the switch groups correspond to the positive and negative periods of the input waveform at the AC port Vac1.
[0051] In specific implementation: the first adjustment circuit includes multiple switch groups, each switch group includes multiple switching transistors, and the switching transistors are arranged and combined to enable bidirectional control of the switch group. In a specific embodiment, a switch group may include two switching transistors. The switching transistors may be IGBT insulated gate bipolar transistors or MOSFET metal oxide semiconductor field-effect transistors. The transistors themselves carry diodes, and the diodes have a freewheeling function. The collectors or emitters of the IGBT transistors in the switch group are connected to each other, or the sources or drains of the MOSFET transistors in the switch group are connected to each other. The connection method may be direct connection, connection on PCB (Printed Circuit Board), or connection at the chip wafer level, thereby realizing bidirectional control of the switch group.
[0052] More specifically, the first regulating circuit includes a first switch group, a second switch group, a third switch group, a fourth switch group, and a primary capacitor C0. The first switch group includes a first switch Q1 and a second switch Q2; the second switch group includes a third switch Q3 and a fourth switch Q4; the third switch group includes a fifth switch Q5 and a sixth switch Q6; and the fourth switch group includes a seventh switch Q7 and an eighth switch Q8. The first and third switch groups form the first bridge arm, and the second and fourth switch groups form the second bridge arm. The first bridge arm, the second bridge arm, and the primary capacitor C0 are connected in parallel to the AC port Vac1. The on / off times of the switch groups correspond to the positive and negative periods of the input waveform at the AC port Vac1. The magnitude and direction of the voltage and current flowing into the second regulating circuit and the transformer circuit are controlled by controlling the on and off times of the first, second, third, and fourth switch groups. In a specific embodiment, the on and off times of the first, second, third, and fourth switch groups determine the magnitude and direction of the current and voltage in the first winding T1_W1. There is coupling between the first winding T1_W1, the second winding T1_W2, and the third winding T1_W3, which in turn determines the magnitude and direction of the current and voltage in the second winding T1_W2 and the third winding T1_W3, thus achieving control over the magnitude and direction of the voltage and current flowing into the second regulating circuit and the transformer circuit.
[0053] More specifically, when AC port Vac1 is used as the input and the first DC port Vdc1 and the second DC port Vdc2 are used as the output ports, when the sine wave input to AC port Vac1 is in the positive half-cycle, the second switch Q2, the fourth switch Q4, the sixth switch Q6, and the eighth switch Q8 open simultaneously, the first switch Q1 and the fifth switch do not open simultaneously, and the third switch Q3 and the seventh switch Q7 open simultaneously. The specific control timing diagram is as follows. Figure 4 As shown; when the sine wave input to AC port Vac1 is in the negative half-cycle, the first switch Q1, the third switch Q3, the fifth switch Q5, and the seventh switch Q7 open simultaneously; the second switch Q2 and the sixth switch do not open simultaneously; and the fourth switch Q4 and the eighth switch Q8 open simultaneously. The specific control timing diagram is as follows. Figure 5 As shown; the simulation waveforms of the voltage changes over time for the first winding T1_W1, the second winding T1_W2, and the third winding T1_W3 of the three-winding transformer T1 are obtained according to the control timing, as shown in the figure. Figure 6 As shown; the overall simulation waveform of the current in the first inductor L1 changing with time, as shown. Figure 7 As shown, the simulation waveform of the current in the first inductor L1 changing with time is as follows. Figure 8 As shown.
[0054] Please refer to Figures 1-9The second regulating circuit includes a ninth switch Q9, a tenth switch Q10, an eleventh switch Q11, a twelfth switch Q12, and a third capacitor C3. The ninth switch Q9 and the eleventh switch Q11 form the third bridge arm, and the tenth switch Q10 and the twelfth switch Q12 form the fourth bridge arm. The third bridge arm, the fourth bridge arm, and the third capacitor C3 are connected in parallel. The on and off times of the ninth switch Q9 and the eleventh switch Q11 are opposite, and the on and off times of the tenth switch Q10 and the twelfth switch Q12 are opposite.
[0055] In specific implementation: the second adjustment circuit includes a ninth switch Q9, a tenth switch Q10, an eleventh switch Q11, a twelfth switch Q12, and a third capacitor C3. The ninth switch Q9 and the eleventh switch Q11 form the third bridge arm, and the tenth switch Q10 and the eleventh switch Q11 form the fourth bridge arm. The third bridge arm, the fourth bridge arm, and the third capacitor C3 are connected in parallel to the first DC port Vdc1. The on / off times of the ninth switch Q9 and the eleventh switch Q11 are opposite, the on / off times of the tenth switch Q10 and the twelfth switch Q12 are opposite, and the on / off times of the ninth switch Q9 and the twelfth switch Q12 are the same. The tenth switch Q10... Similar to the on / off time of the eleventh switch Q11, the magnitude and direction of the output voltage and current at the external port of the second regulating circuit can be controlled by controlling the on / off times of the ninth switch Q9, the tenth switch Q10, the eleventh switch Q11, and the twelfth switch Q12. In a specific embodiment, when charging the load at the second DC port Vdc2, the magnitude and direction of the output voltage and current at the external port of the second regulating circuit can be controlled by controlling the on / off times of the ninth switch Q9, the tenth switch Q10, the eleventh switch Q11, and the twelfth switch Q12, based on the magnitude and direction of the voltage and current on the second winding T1_W2.
[0056] More specifically, when AC port Vac1 is used as input and the first DC port Vdc1 and the second DC port Vdc2 are used as output ports, the simulation waveform of the output current of the second regulating circuit external port, i.e., the first DC port Vdc1, changing with time is obtained according to the two control timing diagrams of the controller 40 for each control switch, as shown in the figure. Figure 9 As shown.
[0057] Please refer to Figures 1-11The transformer circuit includes a dual-channel magnetically coupled inductor L2, a thirteenth switch Q13, a fourteenth switch Q14, a fifteenth switch Q15, a sixteenth switch Q16, and a fourth capacitor C4. The dual-channel magnetically coupled inductor L2 includes a first coil L2_W1 and a second coil L2_W2. The first coil L2_W1 and the second coil L2_W2 share a magnetic core 1 and are magnetically coupled. The thirteenth switch Q13, the fifteenth switch Q15, and the first coil L2_W1 form a first BUCK branch. The fourteenth switch Q14, the sixteenth switch Q16, and the second coil L2_W2 form a second BUCK branch. The first BUCK branch and the second BUCK branch are connected in parallel and are interleaved, and they share a fourth capacitor C4. The on and off times of the fourteenth switch Q14 and the sixteenth switch Q16 are opposite, and the thirteenth switch Q13 and the fourteenth switch Q14 have a phase difference of 0 to 180 degrees.
[0058] In specific implementation: The transformer circuit includes a dual-channel magnetically coupled inductor L2, which includes a first coil L2_W1, a second coil L2_W2, and a common magnetic core 1. The common magnetic core 1 is located between the first coil L2_W1 and the second coil L2_W2, and the first coil L2_W1 is magnetically coupled to the second coil L2_W2 through the common magnetic core 1. The first coil L2_W1 and the second coil L2_W2 act on different branches of the transformer circuit, so that the transformer circuit forms an interleaved parallel double BUCK circuit. The BUCK circuit is a step-down chopper circuit that realizes DC-to-DC step-down conversion. The transformer circuit also includes a thirteenth switch Q13, a fourteenth switch Q14, a sixteenth switch Q16, a fifteenth switch Q15, and a fourth capacitor C4. The thirteenth switch Q13... The fifteenth switch Q15 and the first coil L2_W1 of the dual-channel magnetically coupled inductor L2 form the first branch. The fourteenth switch Q14, the sixteenth switch Q16 and the second coil L2_W2 of the dual-channel magnetically coupled inductor L2 form the second branch. The first branch and the second branch share the fourth capacitor C4 and form two staggered parallel BUCK branches. The on and off times of the thirteenth switch Q13 and the fifteenth switch Q15 are opposite, and the on and off times of the fourteenth switch Q14 and the sixteenth switch Q16 are opposite. The thirteenth switch Q13 and the fourteenth switch Q14 form a phase difference of 0 to 180 degrees. By controlling the on and off times of the thirteenth switch Q13, the fourteenth switch Q14, the sixteenth switch Q16 and the fifteenth switch Q15, the magnitude and direction of the output voltage and current at the external port of the transformer circuit can be controlled.
[0059] More specifically, when AC port Vac1 is used as input and the first DC port Vdc1 and the second DC port Vdc2 are used as output ports, the currents of the first coil L2_W1 and the second coil L2_W2 of the dual-channel magnetically coupled inductor L2 have a certain phase difference, such as... Figure 10As shown, since the pins of the first coil L2_W1 and the second coil L2_W2 do not have fixed polarity directions, the two current transformation curves need to be determined according to the specific connection method of the coils. The currents of the first coil L2_W1 and the second coil L2_W2 are superimposed to reduce ripple current and core loss. The simulation waveform of the output current of the second DC port Vdc2 changing with time is shown below. Figure 11 As shown.
[0060] Please refer to Figures 12-15 A device based on a magnetically coupled dual-bucket and single-stage isolated PFC converter circuit includes a rectifier module, a transformer module 30, and a controller 40. The rectifier module includes a first regulating module 10, a second regulating module 20, and an isolation module 50. The isolation module 50 is used to connect the first regulating module 10, the second regulating module 20, and the transformer module 30 to form electrical isolation. The external ports of the first regulating module 10, the second regulating module 20, and the transformer module 30 include an AC port Vac1 and multiple DC ports, and the external ports are used to connect a power supply or a load. The transformer module 30 includes a multi-channel magnetically coupled inductor, which includes a first coil L2_W1 and a second coil L2_W2 with magnetic circuit coupling. The controller 40 includes an acquisition module 401, an analysis module 402, a judgment module 404, and a control module 403. The analysis module 402 and the judgment module 404 are electrically connected to the acquisition module 401 and the control module 403, respectively. The controller 40 controls the on / off state of each switch in the first adjustment module 10, the second adjustment module 20, and the transformer module 30 to control the magnitude and direction of the output voltage and current of the conversion circuit.
[0061] In specific implementation: The transformer module 30 includes a dual-channel magnetically coupled inductor L2, which includes a non-shared magnetic core 2, a coil, and a shared magnetic core 1. The coil includes a first coil L2_W1 and a second coil L2_W2. A reserved space is provided between the shared magnetic core 1 and the non-shared magnetic core 2. The first coil L2_W1 and the second coil L2_W2 are located in the reserved space, and the shared magnetic core 1 is located between the first coil L2_W1 and the second coil L2_W2, so that the first coil L2_W1 and the second coil L2_W2 form a magnetic circuit coupling, effectively reducing the size of the device, reducing magnetic material loss, and reducing costs.
[0062] More specifically, Figure 15The simulation diagram shows the magnetic flux density of the dual-channel magnetically coupled inductor L2. When current flows into the dual-channel magnetically coupled inductor L2, it converts the voltage and current into magnetic energy for storage. In the diagram, red represents a very high magnetic flux density; the redder the inductor, the higher the magnetic flux density, the greater the loss, and the more severe the heat generation. Green represents a medium level of magnetic flux density, with less loss and less heat generation. Blue represents a very low magnetic flux density, or even zero. As can be seen from the simulation diagram, the common magnetic core 1 of the two inductors is largely green, and even blue areas appear. This indicates that after the magnetic fields of the shared magnetic circuit are superimposed and canceled out, the loss of magnetic materials is greatly reduced, the conversion efficiency is improved, and the heat generation of the inductor is reduced.
[0063] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, apparatus, article, or method that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, apparatus, article, or method. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, apparatus, article, or method that includes that element.
[0064] The above description is only a preferred embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural changes made based on the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.
Claims
1. A converter circuit based on magnetically coupled dual-bucket and single-stage isolated PFC, characterized in that, It includes a rectifier circuit and a transformer circuit. The rectifier circuit is provided with an isolation circuit, which is used to provide electrical isolation so that the rectifier circuit forms a single-stage isolated PFC circuit. The transformer circuit includes multiple coils, and the coils are magnetically coupled to each other. The coils are located on the second inductor of the transformer circuit so that the second inductor forms a multi-channel magnetically coupled inductor. The coils act on different branches of the transformer circuit to form multiple BUCK circuits. The transformer circuit is electrically connected to the rectifier circuit through the isolation circuit; The external ports of the rectifier circuit and the transformer circuit include one AC port and multiple DC ports, and the external ports are used to connect to a power supply or a load.
2. The conversion circuit based on magnetically coupled dual-bucket and single-stage isolated PFC according to claim 1, characterized in that, The rectifier circuit further includes a first regulating circuit and a second regulating circuit, which are connected through the isolation circuit.
3. The conversion circuit based on magnetically coupled dual-bucket and single-stage isolated PFC according to claim 2, characterized in that, The isolation circuit includes a first capacitor, a first inductor, a second capacitor, and a three-winding transformer. The three-winding transformer includes a first winding, a second winding, and a third winding. The first capacitor, the first inductor, and the first winding are connected in series and connected to the first regulating circuit. The second capacitor and the second winding are connected in series and connected to the second regulating circuit. The third winding is connected to the transformer circuit. In the isolation circuit, the first inductor and the three-winding transformer either have the same magnetic core or each have different magnetic cores.
4. The conversion circuit based on magnetically coupled dual-bucket and single-stage isolated PFC according to claim 3, characterized in that, The first regulating circuit includes multiple switch groups, each of which includes multiple switching transistors. The switching transistors are arranged in combination so that the switch groups can be controlled bidirectionally.
5. The conversion circuit based on magnetically coupled dual-bucket and single-stage isolated PFC according to claim 4, characterized in that, The first regulating circuit includes a first switch, a second switch, a third switch, a fourth switch, a fifth switch, a sixth switch, a seventh switch, an eighth switch, and a primary capacitor. The first switch and the second switch form a first switch group, the third switch and the fourth switch form a second switch group, the fifth switch and the sixth switch form a third switch group, and the seventh switch and the eighth switch form a fourth switch group. The first switch group and the third switch group constitute a first bridge arm, and the second switch group and the fourth switch group constitute a second bridge arm. The primary capacitor, the first bridge arm, and the second bridge arm are connected in parallel. The on / off times in the switch group correspond to the positive and negative periods of the input waveform of the AC port.
6. The conversion circuit based on magnetically coupled dual-bucket and single-stage isolated PFC according to claim 5, characterized in that, The second regulating circuit includes a ninth switch, a tenth switch, an eleventh switch, a twelfth switch, and a third capacitor. The ninth switch and the eleventh switch form a third bridge arm, and the tenth switch and the twelfth switch form a fourth bridge arm. The third bridge arm, the fourth bridge arm, and the third capacitor are connected in parallel. The on and off times of the ninth switch and the eleventh switch are opposite, and the on and off times of the tenth switch and the twelfth switch are opposite.
7. The conversion circuit based on magnetically coupled dual-bucket and single-stage isolated PFC according to claim 6, characterized in that, The coil includes a first coil and a second coil; the transformer circuit also includes a thirteenth switch, a fourteenth switch, a fifteenth switch, a sixteenth switch and a fourth capacitor. The thirteenth switch, the fifteenth switch and the first coil of the multi-channel magnetically coupled inductor form a first BUCK branch, and the fourteenth switch, the sixteenth switch and the second coil of the multi-channel magnetically coupled inductor form a second BUCK branch. The first BUCK branch and the second BUCK branch are connected in parallel and share the fourth capacitor. There is a region where the on and off times of the thirteenth switch and the fifteenth switch are partially opposite, and there is a region where the on and off times of the fourteenth switch and the sixteenth switch are partially opposite, and the thirteenth switch and the fourteenth switch form a phase difference of 0 to 180 degrees.
8. A device based on a magnetically coupled dual-bucket and single-stage isolated PFC converter circuit, characterized in that, The device includes a rectifier module, a transformer module, and a controller. The rectifier module includes a first regulating module, a second regulating module, and an isolation module. The isolation module is used to connect the first regulating module, the second regulating module, and the transformer module to form electrical isolation. The external ports of the first regulating module, the second regulating module, and the transformer module include one AC port and multiple DC ports, and the external ports are used to connect to a power supply or a load. The transformer module includes a multi-channel magnetically coupled inductor, which includes a first coil, a second coil, a non-shared magnetic core, and a shared magnetic core. The non-shared magnetic core is located outside the second coil of the first coil and tightly surrounds the first coil and the second coil. The shared magnetic core is located between the first coil and the second coil so that the first coil and the second coil form a magnetic circuit coupling. The controller includes a data acquisition module, an analysis module, a judgment module, and a control module. The analysis module and the judgment module are electrically connected to the data acquisition module and the control module, respectively. The controller controls the on / off state of each switch in the first adjustment module, the second adjustment module, and the transformer module to control the magnitude and direction of the output voltage and current of the conversion circuit.