A two-line pfc circuit and apparatus

Abstract

The embodiment of the application discloses a kind of double-line PFC circuit and device, double-line PFC circuit includes: PFC module, DCDC module and control module, the control module is connected with the PFC module and the DCDC module respectively, the PFC module is connected with the DCDC module, the PFC module, for receiving external input preset voltage range AC, and the preset voltage range AC is converted into direct current, the preset voltage range includes first voltage range and second voltage range;The DCDC module is used to convert the direct current of the PFC module output into the direct current of target voltage, and output the direct current of target voltage;And the control module is used to control the working state of the PFC module and the working state of the DCDC module, to make the double-line PFC circuit convert the preset voltage range AC into the direct current of target voltage.By the above-mentioned mode, it can widen input range, improve the compatibility of product.

Description

Technical Field

[0001] This invention relates to the field of power electronics technology, and in particular to a two-wire PFC (Power Factor Correction) circuit and device. Background Technology

[0002] With the development of electronic power technology, power electronic products are required to have PFC circuits to reduce harmonic pollution to the power grid. Based on the input source, PFC circuits can be divided into single-phase PFC circuits and three-phase PFC circuits. The common input range for single-phase PFC circuits is 80V-264V, while the common input range for three-phase PFC circuits is 300V-485V. Both have relatively narrow input voltage ranges, making them incompatible with different power grid systems and limiting their application scope. Different circuits need to be designed for different power grid systems, resulting in limited applicability. Summary of the Invention

[0003] This invention provides a dual-wire PFC circuit and device that can broaden the input range and improve product compatibility.

[0004] To solve the above-mentioned technical problems, one technical solution adopted in this invention is: providing a dual-wire PFC circuit including: a PFC module, a DC-DC module, and a control module, wherein the control module is connected to both the PFC module and the DC-DC module, and the PFC module is connected to the DC-DC module.

[0005] The PFC module is used to receive AC power within a preset voltage range from an external input and convert the AC power within the preset voltage range into DC power. The preset voltage range includes a first voltage range and a second voltage range.

[0006] The DC-DC module is used to convert the DC power output from the PFC module into DC power at a target voltage, and output the DC power at the target voltage; and

[0007] The control module is used to control the working state of the PFC module and the DCDC module, so that the dual-wire PFC circuit can convert the AC power within the preset voltage range into DC power at the target voltage.

[0008] In some embodiments, the operating states of the PFC module include interleaved parallel operating state and parallel operating state, and the operating states of the DCDC module include full-bridge operating state and half-bridge operating state.

[0009] When the PFC module is connected to AC power within the first voltage range, the control module controls the PFC module to operate in the interleaved parallel operation state so that the PFC module outputs DC power of the second voltage. When the PFC module outputs DC power of the second voltage, the control module controls the DC-DC module to operate in the full-bridge operation state so that the DC-DC module outputs DC power of the target voltage.

[0010] When the PFC module is connected to AC power within the second voltage range, the control module controls the PFC module to operate in parallel mode so that the PFC module outputs DC power at the third voltage. When the PFC module outputs DC power at the third voltage, the control module controls the DC-DC module to operate in half-bridge mode so that the DC-DC module outputs DC power at the target voltage.

[0011] In some embodiments, the PFC module includes a rectifier unit and a two-wire switching unit, wherein the rectifier unit is connected to the AC power supply, and the two-wire switching unit is connected to the rectifier unit.

[0012] The rectifier unit is used to rectify the alternating current;

[0013] The dual-line switching unit is used to output the second voltage DC when the PFC module is in the interleaved parallel working state, and to output the third voltage DC when the PFC module is in the parallel working state.

[0014] In some embodiments, the DC-DC module includes a two-wire switching unit and a resonant unit, wherein the two-wire switching unit is connected to the PFC module, and the resonant unit is connected to the two-wire switching unit.

[0015] The two-wire switching unit is used to provide full-bridge drive for the DC current of the second voltage and half-bridge drive for the DC current of the third voltage.

[0016] The resonant unit is used to provide a dynamic response for the two-wire switching unit, thereby outputting DC current of the target voltage.

[0017] In some embodiments, the rectifier unit includes diodes D3, D4, D5, and D6.

[0018] The first end of diode D3 and the first end of diode D5 are connected to an AC power source. The first end of diode D3 is connected to the second end of diode D4. The first end of diode D4 is connected to the first end of diode D6. The second end of diode D6 is connected to the first end of diode D5. The second end of diode D5 is connected to the second end of diode D3. The second end of diode D3 and the first end of diode D6 are both connected to the two-wire switching unit.

[0019] In some embodiments, the two-wire switching unit includes inductors L1 and L2, switch K1, field-effect transistors Q1 and Q2, capacitor C1, and diodes D1 and D2.

[0020] The second terminal of diode D3 is connected to the first terminal of inductor L1 and the first terminal of inductor L2. The second terminal of inductor L1 is connected to the first terminal of diode D1. The second terminal of inductor L2 is connected to the first terminal of diode D2. The second terminal of diode D1 is connected to the second terminal of diode D2 and the first terminal of capacitor C1. The second terminal of capacitor C1 is connected to the first terminal of diode D6. The first terminal of field-effect transistor Q1 is connected to the second terminal of inductor L1. The second terminal of field-effect transistor Q1 is connected to the first terminal of diode D6. The first terminal of field-effect transistor Q2 is connected to the second terminal of inductor L2. The second terminal of field-effect transistor Q2 is connected to the first terminal of diode D6. The first terminal of switch K1 is connected to the second terminal of inductor L1. The second terminal of switch K1 is connected to the second terminal of inductor L2. The third terminal of switch K1 is connected to the control module.

[0021] In some embodiments, the two-wire switching unit includes field-effect transistors Q3, Q4, Q5, and Q6.

[0022] The first terminal of the field-effect transistor Q3 is connected to the PFC module and the first terminal of the field-effect transistor Q5. The second terminal of the field-effect transistor Q3 is connected to the first terminal of the field-effect transistor Q4 and the resonant unit. The second terminal of the field-effect transistor Q4 is connected to the PFC module and the second terminal of the field-effect transistor Q5. The second terminal of the field-effect transistor Q5 is connected to the resonant unit. The control terminals of the field-effect transistors Q3, Q4, Q5 and Q6 are respectively connected to the control module.

[0023] In some embodiments, the resonant unit includes an inductor L3, a capacitor C2, a transformer T1, and diodes D7, D8, D9, and D10.

[0024] The second terminal of the inductor L3 is connected to the first terminal of the transformer T1, the second terminal of the capacitor C2 is connected to the second terminal of the transformer T1, the third terminal of the transformer T1 is connected to the first terminal of the diode D7 and the second terminal of the diode D8, the fourth terminal of the transformer T1 is connected to the first terminal of the diode D9 and the second terminal of the diode D10, the second terminal of the diode D7 is connected to the second terminal of the diode D9, and the first terminal of the diode D8 is connected to the first terminal of the diode D10.

[0025] In some embodiments, the control module includes a detection unit and a driving unit, the detection unit being connected to the driving unit, the detection unit being connected to the PFC module and the DC-DC module, and the driving unit being connected to the PFC module and the DC-DC module.

[0026] The detection unit is used to detect the voltage range of the AC power input to the PFC module and obtain a first detection result, and to detect the voltage of the DC power input to the DCDC module and obtain a second detection result.

[0027] The control unit is used to control the working state of the PFC module according to the first detection result, and to control the working state of the DCDC module according to the second detection result.

[0028] To solve the above-mentioned technical problems, another technical solution adopted in the embodiments of the present invention is to provide a dual-wire PFC device, including the dual-wire PFC circuit as described above.

[0029] This invention discloses a dual-wire PFC circuit and device. The dual-wire PFC circuit includes a PFC module, a DC-DC converter module, and a control module. The control module is connected to both the PFC module and the DC-DC converter module. The PFC module receives AC power within a preset voltage range from an external input and converts it into DC power. The preset voltage range includes a first voltage range and a second voltage range. The DC-DC converter module converts the DC power output from the PFC module into DC power at a target voltage and outputs the target voltage DC power. The control module controls the operating states of the PFC module and the DC-DC converter module to ensure that the dual-wire PFC circuit converts the AC power within the preset voltage range into the target voltage DC power. This method broadens the input range and improves product compatibility. Attached Figure Description

[0030] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements having the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0031] Figure 1 This is a structural block diagram of the dual-line PFC device provided in an embodiment of the present invention;

[0032] Figure 2 This is a structural block diagram of the dual-line PFC circuit provided in an embodiment of the present invention;

[0033] Figure 3 This is a structural block diagram of the PFC module provided in an embodiment of the present invention;

[0034] Figure 4 This is a schematic diagram of the circuit structure of the PFC module provided in an embodiment of the present invention;

[0035] Figure 5 This is a structural block diagram of the DC-DC module provided in an embodiment of the present invention;

[0036] Figure 6 This is a schematic diagram of the circuit structure of the DC-DC module provided in an embodiment of the present invention. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0038] It should be noted that, unless otherwise specified, the various features in the embodiments of the present invention can be combined with each other, and all are within the protection scope of the present invention. Furthermore, although functional modules are divided in the device schematic diagram and a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different module division or in a different order than that shown in the device schematic diagram or the flowchart.

[0039] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items.

[0040] With the development of electronic power technology, power electronic products are required to incorporate PFC (Power Factor Correction) circuits to reduce harmonic pollution of the power grid. Based on the input source, PFC circuits can be divided into single-phase and three-phase PFC circuits. The common input range for single-phase PFC circuits is 80V to 264V, while for three-phase PFC circuits it is 300V to 485V. Both have relatively narrow input voltage ranges, making them incompatible with different power grid systems and limiting their application scope. This necessitates the design of different circuits for different power grid systems. Therefore, this invention provides a two-wire PFC circuit and device with an input range of 80V-528V, broadening the input voltage range and making it applicable to global user-side power grid systems. This solves the voltage conversion problem required for different power grid systems and reduces the types of circuits required.

[0041] Please see Figure 1 , Figure 1 This is a structural block diagram of the dual-line PFC device 200 provided in an embodiment of the present invention. Figure 1 As shown, one end of the dual-wire PFC device 200 provided in this embodiment of the invention receives AC power within a preset voltage range, and the other end outputs DC power at the target voltage.

[0042] In some embodiments, the preset voltage range is 80V to 528V, and the target voltage is 400V.

[0043] The dual-wire PFC device 200 provided in this embodiment of the invention includes a dual-wire PFC circuit 100 as described below.

[0044] The dual-wire PFC device 200 provided in this embodiment of the invention can convert AC power within a preset voltage range into DC power at a target voltage.

[0045] Please see Figure 2 , Figure 2 This is a structural block diagram of the dual-wire PFC circuit 100 provided in an embodiment of the present invention. Figure 2 As shown, the dual-line PFC circuit 100 provided in this embodiment of the invention includes: a PFC module 10, a DC-DC (Direct Current-Direct Current) module 20, and a control module 30. The control module 30 is connected to the PFC module 10 and the DC-DC module 20, respectively. The PFC module 10 is connected to the DC-DC module 20.

[0046] PFC module 10 receives AC power within a preset voltage range from an external input and converts it into DC power. The preset voltage range includes a first voltage range and a second voltage range. DC-DC module 20 converts the DC power output from PFC module 10 into DC power at a target voltage and outputs the target voltage DC power. Control module 30 controls the operating states of PFC module 10 and DC-DC module 20 to ensure that the two-wire PFC circuit 100 converts AC power within the preset voltage range into DC power at the target voltage.

[0047] The first voltage range can be AC ​​voltage from 80V to 264V, the second voltage range can be input voltage from 265V to 528V, and the target voltage is 400V.

[0048] The dual-wire PFC circuit provided in this embodiment of the invention includes: a PFC module, a DC-DC converter module, and a control module. The control module is connected to both the PFC module and the DC-DC converter module, and the PFC module is connected to the DC-DC converter module. The PFC module receives AC power within a preset voltage range from an external input and converts it into DC power. The preset voltage range includes a first voltage range and a second voltage range. The DC-DC converter module converts the DC power output from the PFC module into DC power at a target voltage and outputs the target voltage DC power. The control module controls the operating states of the PFC module and the DC-DC converter module, so that the dual-wire PFC circuit converts AC power within the preset voltage range into DC power at the target voltage. This method broadens the input range and improves product compatibility.

[0049] In some embodiments, the PFC module 10 operates in an interleaved parallel state and a parallel state, and the DC-DC module 20 operates in a full-bridge state and a half-bridge state. When the PFC module 10 is connected to AC power within a first voltage range, the control module 30 controls the PFC module 10 to operate in an interleaved parallel state so that the PFC module 10 outputs DC power at a second voltage. When the PFC module 10 outputs DC power at the second voltage, the control module 30 controls the DC-DC module 20 to operate in a full-bridge state so that the DC-DC module 20 outputs DC power at a target voltage. When the PFC module 10 is connected to AC power within a second voltage range, the control module 30 controls the PFC module 10 to operate in a parallel state so that the PFC module 10 outputs DC power at a third voltage. When the PFC module 10 outputs DC power at the third voltage, the control module 30 controls the DC-DC module 20 to operate in a half-bridge state so that the DC-DC module 20 outputs DC power at the target voltage.

[0050] Specifically, when the AC voltage input to the dual-wire PFC circuit 100 is within a first voltage range, i.e., 80V to 264V, the control module 30 first detects the voltage of the power supply input to the PFC module 10. After detecting that the AC voltage input to the PFC module 10 is within the first voltage range (80V to 264V), the control module 30 controls the PFC module 10 to operate in an interleaved parallel state, thereby causing the PFC module 10 to output a second voltage DC voltage. In this embodiment, the second voltage can be 400V. Then, the control module 30 detects the voltage of the power supply input to the DC-DC module 20. When the PFC module 10 outputs the second voltage, i.e., 400V DC, the control module 30 controls the DC-DC module 20 to operate in a full-bridge state, thereby causing the DC-DC module 20 to output a target voltage DC voltage. In this embodiment, the target voltage can be 400V.

[0051] When the AC voltage input to the dual-wire PFC circuit 100 is within the second voltage range, i.e., 265V to 528V, the control module 30 first detects the voltage of the power supply input to the PFC module 10. After detecting that the AC voltage input to the PFC module 10 is within the second voltage range (265V to 528V), the control module 30 controls the PFC module 10 to operate in parallel, thereby outputting a third voltage (DC) from the PFC module 10. In this embodiment, the third voltage can be 800V. Then, the control module 30 detects the voltage of the power supply input to the DC-DC module 20. When the PFC module 10 outputs the third voltage (800V DC), the control module 30 controls the DC-DC module 20 to operate in a half-bridge state, thereby outputting a target voltage (400V DC) from the DC-DC module 20.

[0052] In some embodiments, the control module 30 includes a detection unit and a drive unit. The detection unit is connected to the drive unit, the PFC module 10, and the DC-DC module 20, respectively. The drive unit is also connected to the PFC module 10 and the DC-DC module 20. The detection unit is used to detect the voltage range of the AC power input to the PFC module 10 and obtain a first detection result, and to detect the voltage of the DC power input to the DC-DC module 20 and obtain a second detection result. The control unit is used to control the operating state of the PFC module 10 based on the first detection result, and to control the operating state of the DC-DC module 20 based on the second detection result.

[0053] Specifically, when the first detection result indicates that the AC voltage range of the input PFC module 10 is within a first voltage range (80V to 264V), the control unit controls the PFC module 10 to operate in an interleaved parallel mode. When the first detection result indicates that the AC voltage range of the input PFC module 10 is within a second voltage range (265V to 528V), the control unit controls the PFC module 10 to operate in a parallel mode.

[0054] When the second detection result indicates that the DC voltage input to the DC-DC module 20 is the second voltage, i.e., 400V, the control unit controls the DC-DC module 20 to operate in a full-bridge state. When the second detection result indicates that the DC voltage input to the DC-DC module 20 is the third voltage, i.e., 800V, the control unit controls the DC-DC module 20 to operate in a half-bridge state.

[0055] It is worth noting that any existing or future detection and control methods can be applied to one or more embodiments provided in this invention.

[0056] Please see Figure 3 , Figure 3 This is a structural block diagram of the PFC module 10 provided in an embodiment of the present invention. Figure 3 As shown, in some embodiments, the PFC module 10 includes a rectifier unit 101 and a two-wire switching unit 102. The rectifier unit 101 is connected to AC power, and the two-wire switching unit 102 is connected to the rectifier unit 101. The rectifier unit 101 is used to rectify the AC power. The two-wire switching unit 102 is used to output a second voltage DC power when the PFC module 10 is in an interleaved parallel operating state, and to output a third voltage DC power when the PFC module 10 is in a parallel operating state.

[0057] Please see Figure 4 , Figure 4 This is a schematic diagram of the circuit structure of the PFC module 10 provided in an embodiment of the present invention. Figure 4 As shown, in some embodiments, the rectifier unit 101 includes diodes D3, D4, D5, and D6. The first ends of diodes D3 and D5 are connected to an AC power supply. The first end of diode D3 is connected to the second end of diode D4, the first end of diode D4 is connected to the first end of diode D6, the second end of diode D6 is connected to the first end of diode D5, the second end of diode D5 is connected to the second end of diode D3, and both the second end of diode D3 and the first end of diode D6 are connected to the two-wire switching unit 102.

[0058] It is worth noting that the components and layout of the rectifier unit in the embodiments of this disclosure are not limited to the circuit structure of the rectifier unit described above. Any existing or future rectification method can be applied to one or more embodiments provided in this disclosure.

[0059] In some embodiments, the dual-line switching unit 102 includes inductors L1 and L2, switch K1, field-effect transistors Q1 and Q2, capacitor C1, and diodes D1 and D2. The second terminal of diode D3 is connected to the first terminals of inductors L1 and L2. The second terminal of inductor L1 is connected to the first terminal of diode D1. The second terminal of inductor L2 is connected to the first terminal of diode D2. The second terminal of diode D1, the second terminal of diode D2, and the first terminal of capacitor C1 are connected. The second terminal of capacitor C1 is connected to the first terminal of diode D6. The first terminal of field-effect transistor Q1 is connected to the second terminal of inductor L1. The second terminal of field-effect transistor Q1 is connected to the first terminal of diode D6. The first terminal of field-effect transistor Q2 is connected to the second terminal of inductor L2. The second terminal of field-effect transistor Q2 is connected to the first terminal of diode D6. The first terminal of switch K1 is connected to the second terminal of inductor L1. The second terminal of switch K1 is connected to the second terminal of inductor L2. The third terminal of switch K1 is connected to the control module 30.

[0060] Specifically, when the input AC current is within the first voltage range of 80V to 264V, the control module 30 controls switch K1 to open, thus forming a first power factor regulation circuit consisting of inductor L1, diode D1, and MOSFET Q1, and a second power factor regulation circuit consisting of inductor L2, diode D2, and MOSFET Q2. MOSFETs Q1 and Q2 are driven with a 180° phase difference, thus the first and second power factor regulation circuits are connected in an interleaved parallel relationship. At this time, the voltage of the current output by the PFC module 10 is the second voltage, 400V. Because the input AC current voltage is relatively low, the input current is relatively large. Only a large inductor can achieve low ripple. Therefore, the inductance values ​​of inductors L1 and L2 are both relatively large. Furthermore, since the PFC module 10 is in an interleaved parallel operating state, the ripple of the output current of the PFC module 10 can be significantly reduced, thereby achieving low ripple output.

[0061] When the input AC voltage is within the second voltage range (265V to 528V), the control module 30 closes the control switch K1. At this time, inductors L1 and L2 are connected in parallel, MOSFETs Q1 and Q2 are connected in parallel, and diodes D1 and D2 are connected in parallel. The first and second power factor regulation circuits are connected in parallel, and the PFC module 10 operates in parallel. The voltage of the output current from the PFC module 10 at this time is the third voltage, 800V. Because the input voltage is relatively high, the input current is relatively low, which is not conducive to loop control. However, the parallel connection of inductors L1 and L2 reduces the inductance by half, which is beneficial for loop control and achieves low ripple output.

[0062] It should be noted that the voltage value of the output current can be changed by altering the inductance values ​​of inductors L1 and L2, as well as the capacitance of the capacitor. That is, the second voltage is not limited to 400V, and the third voltage is not limited to 800V.

[0063] Please see Figure 5 , Figure 5 This is a structural block diagram of the DC-DC module 20 provided in an embodiment of the present invention.

[0064] In some embodiments, the DC-DC module 20 includes a two-wire switching unit 201 and a resonant unit 202. The two-wire switching unit 201 is connected to the PFC module 10, and the resonant unit 202 is connected to the two-wire switching unit 201.

[0065] The two-wire switching unit 201 is used to provide full-bridge drive for the second voltage DC power and half-bridge drive for the third voltage DC power.

[0066] The resonant unit 202 is used to provide a dynamic response for the two-wire switching unit 201, thereby outputting DC current at the target voltage.

[0067] Please see Figure 6 , Figure 6 This is a schematic diagram of the circuit structure of the DC-DC module 20 provided in an embodiment of the present invention.

[0068] In some embodiments, the two-wire switching unit 201 includes field-effect transistors Q3, Q4, Q5, and Q6.

[0069] The first terminal of field-effect transistor Q3 is connected to the first terminal of PFC module 10 and field-effect transistor Q5. The second terminal of field-effect transistor Q3 is connected to the first terminal of field-effect transistor Q4 and resonant unit 202. The second terminal of field-effect transistor Q4 is connected to the second terminal of PFC module 10 and field-effect transistor Q5. The second terminal of field-effect transistor Q5 is connected to resonant unit 202. The control terminals of field-effect transistors Q3, Q4, Q5 and Q6 are respectively connected to control module 30.

[0070] The control module 30 can control the working state of the DC-DC module 20 by controlling the on / off state of the field-effect transistors Q3, Q4, Q5 and Q6.

[0071] In some embodiments, the resonant unit 202 includes an inductor L3, a capacitor C2, a transformer T1, and diodes D7, D8, D9, and D10.

[0072] The second terminal of inductor L3 is connected to the first terminal of transformer T1, the second terminal of capacitor C2 is connected to the second terminal of transformer T1, the third terminal of transformer T1 is connected to the first terminal of diode D7 and the second terminal of diode D8, the fourth terminal of transformer T1 is connected to the first terminal of diode D9 and the second terminal of diode D10, the second terminal of diode D7 is connected to the second terminal of diode D9, and the first terminal of diode D8 is connected to the first terminal of diode D10.

[0073] The DC-DC module 20 can switch between full-bridge and half-bridge operation. When the control module 30 detects that the voltage output by the PFC module 10 is the second voltage, i.e., 400V, the control module 30 drives MOSFETs Q3, Q4, Q5, and Q6 as switches to operate at high frequency, and the DC-DC module 20 is in full-bridge operation at this time. The driving waveforms of MOSFETs Q3 and Q6 are the same. The driving waveforms of MOSFETs Q4 and Q5 are the same and complementary to those of MOSFETs Q3 and Q6. The turns ratio of the primary and secondary sides of transformer T1 is 1:1, thus controlling the operating frequency of the DC-DC module 20 to be exactly at the resonant point. The output current voltage of the DC-DC module 20 is the target voltage, i.e., 400V, ensuring the dynamic response of the DC-DC module 20 and thus guaranteeing a low-ripple output current.

[0074] When the control module 30 detects that the output voltage of the PFC module 10 is the third voltage, i.e., 800V, the control module 30 drives the field-effect transistors Q3 and Q4 to operate at high frequency as switches. The driving waveforms of the field-effect transistors Q3 and Q4 are complementary. Field-effect transistor Q5 remains open, and field-effect transistor Q6 remains closed. At this time, the DC-DC module 20 operates in a half-bridge state. The input voltage of the DC-DC module 20 is the third voltage, i.e., 800V, and the output voltage is the target voltage, i.e., 400V. The turns ratio of the primary and secondary sides of the transformer T1 is 1:1. The operating frequency of the DC-DC module 20 is also at the resonant point, ensuring the dynamic response of the DC-DC module 20 and thus guaranteeing low output ripple.

[0075] By selecting appropriate circuit parameters, the DC-DC module 20 can always operate near the resonant point, resulting in a faster dynamic response and smaller output ripple in the dual-wire PFC circuit 100.

[0076] It should be noted that the voltage value of the output current can be changed by altering the duty cycle and frequency of MOSFETs Q3, Q4, Q5, and Q6, as well as the turns ratio of the primary and secondary sides of transformer T1. Therefore, the target voltage in this embodiment of the invention is not limited to 400V.

[0077] This invention discloses a dual-wire PFC circuit 100. The dual-wire PFC circuit 100 receives AC power within a preset voltage range from an external input via a PFC module 10 and converts it into DC power. The preset voltage range includes a first voltage range and a second voltage range. A DC-DC module 20 converts the DC power output from the PFC module 10 into DC power at a target voltage and outputs the target voltage DC power. A control module 30 controls the operating states of the PFC module 10 and the DC-DC module 20 to ensure that the dual-wire PFC circuit 100 converts AC power within the preset voltage range into DC power at the target voltage. The input voltage range of the dual-wire PFC circuit 100 is 80V-528V, and the output voltage can be 400V. The PFC module 10 of the dual-wire PFC circuit 100 is an interleaved parallel-to-parallel circuit. The DC-DC module 20 of the dual-wire PFC circuit 100 is a full-bridge to half-bridge circuit. When the input voltage is between 80V and 264V, the PFC module 10 operates in an interleaved parallel configuration, while the DC-DC module 20 operates in a full-bridge configuration. When the input voltage is between 265V and 528V, the PFC module 10 operates in a parallel configuration, while the DC-DC module 20 operates in a half-bridge configuration. With appropriate component parameters, a wide range of input voltages can be achieved, while also meeting the requirements for low ripple output current. This invention expands the input range while meeting the requirements for low ripple, fast response, and isolation. It can be widely applied in industrial, consumer, and medical products, improving the circuit's versatility, reducing the number of circuit types, thereby lowering product development and maintenance costs for enterprises, and reducing material costs.

[0078] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; under the concept of the present invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the present invention as described above, which are not provided in detail for the sake of brevity; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A two-wire PFC circuit, characterized in that, include: The system comprises a PFC module, a DC-DC converter module, and a control module, wherein the control module is connected to both the PFC module and the DC-DC converter module, and the PFC module is connected to the DC-DC converter module. The PFC module is used to receive AC power within a preset voltage range from an external input and convert the AC power within the preset voltage range into DC power. The preset voltage range includes a first voltage range and a second voltage range. The DC-DC module is used to convert the DC power output from the PFC module into DC power at a target voltage, and output the DC power at the target voltage; and The control module is used to control the working state of the PFC module and the DCDC module, so that the dual-wire PFC circuit can convert the AC power within the preset voltage range into DC power at the target voltage. The PFC module includes a rectifier unit and a two-wire switching unit. The rectifier unit is connected to the AC power supply, and the two-wire switching unit is connected to the rectifier unit. The two-wire switching unit includes inductors L1 and L2, a switch K1, MOSFETs Q1 and Q2, a capacitor C1, and diodes D1 and D2. The rectifier unit includes diodes D3, D4, D5, and D6. The second terminal of diode D1 is connected to the first terminal of inductor L1 and the first terminal of inductor L2. The second terminal of inductor L1 is connected to the first terminal of diode D1. The second terminal of inductor L2 is connected to the first terminal of diode D2. The second terminal of diode D1 is connected to the second terminal of diode D2 and the first terminal of capacitor C1. The second terminal of capacitor C1 is connected to the first terminal of diode D6. The first terminal of field-effect transistor Q1 is connected to the second terminal of inductor L1. The second terminal of field-effect transistor Q1 is connected to the first terminal of diode D6. The first terminal of field-effect transistor Q2 is connected to the second terminal of inductor L2. The second terminal of field-effect transistor Q2 is connected to the first terminal of diode D6. The first terminal of switch K1 is connected to the second terminal of inductor L1. The second terminal of switch K1 is connected to the second terminal of inductor L2. The third terminal of switch K1 is connected to the control module. The first end of diode D3 and the first end of diode D5 are connected to AC power. The first end of diode D3 is connected to the second end of diode D4. The first end of diode D4 is connected to the first end of diode D6. The second end of diode D6 is connected to the first end of diode D5. The second end of diode D5 is connected to the second end of diode D3. The second end of diode D3 and the first end of diode D6 are both connected to the two-wire switching unit.

2. The dual-wire PFC circuit according to claim 1, characterized in that, The PFC module operates in two states: interleaved parallel operation and parallel operation. The DC-DC module operates in two states: full-bridge operation and half-bridge operation. When the PFC module is connected to AC power within the first voltage range, the control module controls the PFC module to operate in the interleaved parallel operation state so that the PFC module outputs DC power of the second voltage. When the PFC module outputs DC power of the second voltage, the control module controls the DC-DC module to operate in the full-bridge operation state so that the DC-DC module outputs DC power of the target voltage. When the PFC module is connected to AC power within the second voltage range, the control module controls the PFC module to operate in parallel mode so that the PFC module outputs DC power at the third voltage. When the PFC module outputs DC power at the third voltage, the control module controls the DC-DC module to operate in half-bridge mode so that the DC-DC module outputs DC power at the target voltage.

3. The dual-wire PFC circuit according to claim 2, characterized in that, The rectifier unit is used to rectify the alternating current; The dual-line switching unit is used to output the second voltage DC when the PFC module is in the interleaved parallel working state, and to output the third voltage DC when the PFC module is in the parallel working state.

4. The dual-wire PFC circuit according to claim 3, characterized in that, The DC-DC module includes a two-wire switching unit and a resonant unit. The two-wire switching unit is connected to the PFC module, and the resonant unit is connected to the two-wire switching unit. The two-wire switching unit is used to provide full-bridge drive for the DC current of the second voltage and half-bridge drive for the DC current of the third voltage. The resonant unit is used to provide a dynamic response for the two-wire switching unit, thereby outputting DC current of the target voltage.

5. The dual-wire PFC circuit according to claim 4, characterized in that, The two-wire switching unit includes field-effect transistors Q3, Q4, Q5, and Q6. The first terminal of the field-effect transistor Q3 is connected to the PFC module and the first terminal of the field-effect transistor Q5. The second terminal of the field-effect transistor Q3 is connected to the first terminal of the field-effect transistor Q4 and the resonant unit. The second terminal of the field-effect transistor Q4 is connected to the PFC module and the second terminal of the field-effect transistor Q5. The second terminal of the field-effect transistor Q5 is connected to the resonant unit. The control terminals of the field-effect transistors Q3, Q4, Q5 and Q6 are respectively connected to the control module.

6. The dual-wire PFC circuit according to claim 5, characterized in that, The resonant unit includes an inductor L3, a capacitor C2, a transformer T1, and diodes D7, D8, D9, and D10. The second terminal of the inductor L3 is connected to the first terminal of the transformer T1, the second terminal of the capacitor C2 is connected to the second terminal of the transformer T1, the third terminal of the transformer T1 is connected to the first terminal of the diode D7 and the second terminal of the diode D8, the fourth terminal of the transformer T1 is connected to the first terminal of the diode D9 and the second terminal of the diode D10, the second terminal of the diode D7 is connected to the second terminal of the diode D9, and the first terminal of the diode D8 is connected to the first terminal of the diode D10.

7. The dual-wire PFC circuit according to any one of claims 1-6, characterized in that, The control module includes a detection unit and a drive unit. The detection unit is connected to the drive unit, the detection unit is connected to the PFC module and the DC-DC module, and the drive unit is connected to the PFC module and the DC-DC module. The detection unit is used to detect the voltage range of the AC power input to the PFC module and obtain a first detection result, and to detect the voltage of the DC power input to the DCDC module and obtain a second detection result. The driving unit is used to control the working state of the PFC module according to the first detection result, and to control the working state of the DCDC module according to the second detection result.

8. A dual-line PFC device, characterized in that, Includes a two-wire PFC circuit as described in any one of claims 1-7.

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