Three-phase BUCK active PFC circuit, circuit board, controller and air conditioner

Abstract

The utility model discloses a three-phase BUCK active PFC circuit, a circuit board, a controller and an air conditioner, the three-phase BUCK active PFC circuit comprises an input filtering module, a rectification module, an output filtering module, an inversion module and a voltage absorption module, the input filtering module is connected with a three-phase AC power supply; the rectification module is connected with the input filtering module; the output filter module comprises a first output filter inductor and an output filter capacitor which are connected in series, and the output filter module is connected with the direct current output end of the rectifier module; the output filter capacitor is a non-electrolytic capacitor; the inversion module is connected with two ends of the output filter capacitor; the voltage absorption module is located between the output filter capacitor and the inversion module and comprises a voltage-regulator tube, an absorption capacitor and an absorption resistor, one end of the output filter capacitor is connected to a cathode of the voltage-regulator tube, and an anode of the voltage-regulator tube is connected to one end of the absorption capacitor and one end of the absorption resistor; the other end of the absorption capacitor and the other end of the absorption resistor are connected to the other end of the output filter capacitor. The reliability and stability of the circuit can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of circuits, and in particular to a three-phase BUCK active PFC circuit, a circuit board, a controller and an air conditioner. Background Art

[0002] The three-phase BUCK active PFC circuit can realize step-down control and has a lower bus voltage, which provides a larger voltage space for the selection of the inverter switch at the later stage and is widely used in high-power occasions. At present, the output capacitor of the traditional three-phase BUCK active PFC generally adopts electrolytic capacitors, but because electrolytic capacitors need to withstand large ripple currents, they generate serious heat during actual operation, which greatly restricts the life of the electric control; the output capacitor of the three-phase BUCK active PFC rarely adopts non-electrolytic capacitors. This is because the capacity of non-electrolytic capacitors is small. If the induced electromotive force generated by the sudden shutdown of the load carried by the circuit charges the non-electrolytic capacitor, the voltage borne by the non-electrolytic capacitor will suddenly increase, thus affecting the working reliability and stability of the circuit. Utility Model Content

[0003] The purpose of the utility model is to solve at least one of the technical problems existing in the prior art, and to provide a three-phase BUCK active PFC circuit, a circuit board, a controller and an air conditioner, which can improve the reliability and stability of the circuit.

[0004] In a first aspect, an embodiment of the utility model provides a three-phase BUCK active PFC circuit, including an input filter module, a rectifier module, an output filter module, an inverter module and a voltage absorption module, wherein:

[0005] The input filter module is connected to a three-phase AC power supply;

[0006] The rectifier module is connected to the input filter module;

[0007] The output filter module comprises a first output filter inductor and an output filter capacitor connected in series, and the output filter module is connected to the DC output end of the rectifier module; the output filter capacitor is a non-electrolytic capacitor;

[0008] The inverter module is connected to both ends of the output filter capacitor;

[0009] The voltage absorption module is located between the output filter capacitor and the inverter module, and includes a voltage regulator, an absorption capacitor and an absorption resistor. One end of the output filter capacitor is connected to the cathode of the voltage regulator, the anode of the voltage regulator is connected to one end of the absorption capacitor and one end of the absorption resistor, and the other end of the absorption capacitor and the other end of the absorption resistor are both connected to the other end of the output filter capacitor.

[0010] According to the three-phase BUCK active PFC circuit provided by the embodiment of the utility model, at least the following beneficial effects are achieved: the three-phase AC power supply is supplied to the rear-end load after passing through the input filter module, the rectifier module, the output filter module and the inverter module in sequence, wherein the output filter module adopts a non-electrolytic capacitor as the output filter capacitor, and a voltage absorption module is arranged between the output filter capacitor and the inverter module, when the induced electromotive force generated by the sudden shutdown of the load makes the voltage across the output filter capacitor reach the breakdown voltage of the voltage regulator tube, the voltage regulator tube is broken down, the absorption capacitor is charged, and the induced electromotive force is absorbed by the absorption capacitor and the absorption resistor in the voltage absorption module, thereby stabilizing the voltage across the output filter capacitor; therefore, in the three-phase BUCK active PFC circuit, the output filter capacitor will not be impacted by abnormal voltage, when the circuit works normally, the voltage regulator tube is not broken down, the absorption resistor will consume the energy of the absorption capacitor, the absorption capacitor is not charged, does not need to bear a large ripple current, has low heat generation, and the entire circuit has high reliability and stability.

[0011] According to the three-phase BUCK active PFC circuit provided by some embodiments of the present invention, the voltage absorption module includes a plurality of the voltage regulator tubes, and the plurality of the voltage regulator tubes are connected in series.

[0012] According to the three-phase BUCK active PFC circuit provided by some embodiments of the present invention, the output filter module also includes a second output filter inductor, and the first output filter inductor, the output filter capacitor and the second output filter inductor are connected in sequence.

[0013] According to the three-phase BUCK active PFC circuit provided by some embodiments of the present utility model, the rectifier module includes a first bridge arm formed by a first diode and a second diode connected in series, a second bridge arm formed by a third diode and a fourth diode connected in series, a third bridge arm formed by a fifth diode and a sixth diode connected in series, and three bidirectional controllable switches, the first bridge arm, the second bridge arm and the third bridge arm are connected in parallel to each other, the input filter module is respectively connected to one end of the three bidirectional controllable switches, and the other ends of the three bidirectional controllable switches are respectively connected to the midpoint of the first bridge arm, the midpoint of the second bridge arm and the midpoint of the third bridge arm.

[0014] According to the three-phase BUCK active PFC circuit provided by some embodiments of the present invention, the implementation method of the bidirectional controllable switch includes the following cases:

[0015] Case 1: comprising a first switch tube and a second switch tube connected in series, the first switch tube and the second switch tube have opposite conduction directions and are respectively provided with anti-parallel diodes;

[0016] Case 2: comprising a forward conducting branch and a reverse conducting branch connected in parallel, wherein the forward conducting branch comprises a third switch tube and a seventh diode connected in series, and the reverse conducting branch comprises a fourth switch tube and an eighth diode connected in series;

[0017] Case 3: comprising a fourth bridge arm formed by a ninth diode and a tenth diode connected in series, a fifth bridge arm formed by an eleventh diode and a twelfth diode connected in series, and a sixth bridge arm formed by a fifth switch tube, wherein the fourth bridge arm, the fifth bridge arm and the sixth bridge arm are connected in parallel to each other;

[0018] Case 4: Including RB-IGBT devices.

[0019] According to the three-phase BUCK active PFC circuit provided by some embodiments of the present invention, the input filter module includes three input filter inductors and three input filter capacitors; one end of the three input filter inductors is respectively connected to the three-phase AC power supply, and the other end is respectively connected to one end of the three input filter capacitors; the other ends of the three input filter capacitors are connected together.

[0020] According to some embodiments of the utility model, the three-phase BUCK active PFC circuit provided further includes a freewheeling diode, wherein the positive electrode of the freewheeling diode is connected to the negative electrode of the DC output terminal of the rectifier module, and the negative electrode of the freewheeling diode is connected to the positive electrode of the DC output terminal of the rectifier module.

[0021] In a second aspect, an embodiment of the utility model provides a circuit board, comprising the three-phase BUCK active PFC circuit as described in the embodiment of the first aspect above.

[0022] In a third aspect, an embodiment of the utility model provides a controller, comprising the circuit board as described in the embodiment of the second aspect above.

[0023] In a fourth aspect, an embodiment of the utility model provides an air conditioner, comprising the circuit board as described in the embodiment of the second aspect above or comprising the controller as described in the embodiment of the third aspect above.

[0024] Other features and advantages of the utility model will be described in the following description, and partly become apparent from the description, or understood by practicing the utility model. The purpose and other advantages of the utility model can be realized and obtained by the structures specifically pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are used to provide a further understanding of the technical solution of the utility model and constitute a part of the specification. Together with the embodiments of the utility model, they are used to explain the technical solution of the utility model and do not constitute a limitation on the technical solution of the utility model.

[0026] The utility model is further described below in conjunction with the accompanying drawings and embodiments;

[0027] Figure 1 It is a circuit schematic diagram of a three-phase BUCK active PFC circuit provided in Embodiment 1 of the present utility model;

[0028] Figure 2 It is the waveform of the bus voltage outputted from the output filter module to the inverter module during normal driving;

[0029] Figure 3 When the motor load carried by the inverter module suddenly stops, if there is no voltage absorption module, the waveform of the bus voltage output by the output filter module to the inverter module;

[0030] Figure 4 for Figure 1 The three-phase BUCK active PFC circuit shown shows the waveform of the bus voltage output from the output filter module to the inverter module when the motor load carried by the inverter module suddenly stops;

[0031] Figure 5 It is a circuit schematic diagram of a three-phase BUCK active PFC circuit provided in Embodiment 2 of the present utility model;

[0032] Figure 6 It is a circuit schematic diagram of a three-phase BUCK active PFC circuit provided in Embodiment 3 of the present utility model;

[0033] Figure 7a It is a device principle diagram of the first implementation mode of the bidirectional controllable switch provided by the embodiment of the utility model;

[0034] Figure 7b It is a device principle diagram of the second implementation mode of the bidirectional controllable switch provided in the embodiment of the utility model;

[0035] Figure 7c It is a device principle diagram of the third implementation mode of the bidirectional controllable switch provided in the embodiment of the utility model;

[0036] Figure 7d It is a device principle diagram of a fourth implementation mode of a bidirectional controllable switch provided in an embodiment of the utility model;

[0037] Figure 7e It is a device principle diagram of the fifth implementation method of the bidirectional controllable switch provided in the embodiment of the utility model. DETAILED DESCRIPTION

[0038] This section will describe in detail the specific embodiments of the utility model. The preferred embodiments of the utility model are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the utility model, but it cannot be understood as a limitation on the protection scope of the utility model.

[0039] In the description of the embodiments of the present utility model, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed", etc. are understood to exclude the number itself, "above", "below", "within", etc. are understood to include the number itself, "at least one" means one or more, "at least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items. If there is a description of "first", "second", etc., it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0040] It should be noted that the words such as setting, installing, and connecting in the embodiments of the present invention should be understood in a broad sense, and the technical personnel in the relevant technical field can reasonably determine the specific meanings of the above words in the embodiments of the present invention in combination with the specific content of the technical solution. For example, the term "connection" can be a mechanical connection, an electrical connection, or mutual communication; it can be directly connected or indirectly connected through an intermediate medium.

[0041] It should be noted that the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0042] The three-phase BUCK active PFC circuit can realize step-down control and has a lower bus voltage, which provides a larger voltage space for the selection of the inverter switch at the later stage and is widely used in high-power occasions. At present, the output capacitor of the traditional three-phase BUCK active PFC generally adopts electrolytic capacitors, but because electrolytic capacitors need to withstand large ripple currents, they generate serious heat during actual operation, which greatly restricts the life of the electric control; the output capacitor of the three-phase BUCK active PFC rarely adopts non-electrolytic capacitors. This is because the capacity of non-electrolytic capacitors is small. If the induced electromotive force generated by the sudden shutdown of the load carried by the circuit charges the non-electrolytic capacitor, the voltage borne by the non-electrolytic capacitor will suddenly increase, thus affecting the working reliability and stability of the circuit.

[0043] Based on this, the embodiments of the present utility model provide a three-phase BUCK active PFC circuit, a circuit board, a controller and an air conditioner, which can improve the reliability and stability of the circuit.

[0044] The following is a further description of the embodiments of the present invention in conjunction with the accompanying drawings.

[0045] Reference Figure 1 The first embodiment of the utility model provides a three-phase BUCK active PFC circuit, including an input filter module 100, a rectifier module 200, an output filter module 300, an inverter module 500 and a voltage absorption module 400, wherein:

[0046] The input filter module 100 is connected to the three-phase AC power supply; specifically, the input filter module 100 includes three input filter inductors and three input filter capacitors; one end of the three input filter inductors is respectively connected to the three-phase AC power supply, and the other end is respectively connected to one end of the three input filter capacitors; the other ends of the three input filter capacitors are connected together; Figure 1 As shown, the three input filter inductors are respectively an inductor L1, an inductor L2 and an inductor L3, and the three input filter capacitors are respectively a capacitor C1, a capacitor C2 and a capacitor C3; one end of the inductor L1 is connected to the A phase of the three-phase AC power supply, and the other end of the inductor L1 is connected to one end of the capacitor C1; one end of the inductor L2 is connected to the B phase of the three-phase AC power supply, and the other end of the inductor L2 is connected to one end of the capacitor C2; one end of the inductor L3 is connected to the C phase of the three-phase AC power supply, and the other end of the inductor L3 is connected to one end of the capacitor C3; the other end of the capacitor C1, the other end of the capacitor C2 and the other end of the capacitor C3 are connected together;

[0047] The rectifier module 200 is connected to the input filter module 100; specifically, the rectifier module 200 includes a first bridge arm formed by a first diode D1 and a second diode D2 connected in series, a second bridge arm formed by a third diode D3 and a fourth diode D4 connected in series, a third bridge arm formed by a fifth diode D5 and a sixth diode D6 connected in series, and three bidirectional controllable switches, the first bridge arm, the second bridge arm and the third bridge arm are connected in parallel to each other, the input filter module 100 is respectively connected to one end of the three bidirectional controllable switches, and the other ends of the three bidirectional controllable switches are respectively connected to the midpoint of the first bridge arm, the midpoint of the second bridge arm and the midpoint of the third bridge arm; Figure 1 As shown, the three bidirectional controllable switches are respectively a bidirectional controllable switch SA, a bidirectional controllable switch SB and a bidirectional controllable switch SC, the connection point of the inductor L1 and the capacitor C1 is connected to one end of the bidirectional controllable switch SA, the other end of the bidirectional controllable switch SA is connected to the connection point of the first diode D1 and the second diode D2, the connection point of the inductor L2 and the capacitor C2 is connected to one end of the bidirectional controllable switch SB, the other end of the bidirectional controllable switch SB is connected to the connection point of the third diode D3 and the fourth diode D4, the connection point of the inductor L3 and the capacitor C3 is connected to one end of the bidirectional controllable switch SC, and the other end of the bidirectional controllable switch SC is connected to the connection point of the fifth diode D5 and the sixth diode D6;

[0048] The output filter module 300 includes a first output filter inductor L4 and an output filter capacitor C4 connected in series. The output filter module 300 is connected to the DC output terminal of the rectifier module 200; the output filter capacitor C4 is a non-electrolytic capacitor; specifically, Figure 1 As shown, the positive pole of the DC output terminal of the rectifier module 200 is connected to one end of the first output filter inductor L4, the other end of the first output filter inductor L4 is connected to one end of the output filter capacitor C4, and the other end of the output filter capacitor C4 is connected to the negative pole of the DC output terminal of the rectifier module 200, that is, the first output filter inductor L4 is arranged between the positive pole of the DC output terminal of the rectifier module 200 and one end of the output filter capacitor C4; it can be understood that the first output filter inductor L4 can also be arranged between the negative pole of the DC output terminal of the rectifier module 200 and the other end of the output filter capacitor C4, that is, the positive pole of the DC output terminal of the rectifier module 200 is directly connected to one end of the output filter capacitor C4, the other end of the output filter capacitor C4 is connected to one end of the first output filter inductor L4, and the other end of the first output filter inductor L4 is connected to the negative pole of the DC output terminal of the rectifier module 200;

[0049] The inverter module 500 is connected to both ends of the output filter capacitor C4; it can be understood that after the voltage at both ends of the output filter capacitor C4 is inverted by the inverter module, an AC voltage with the required frequency and amplitude is output to the rear-end load;

[0050] The voltage absorption module 400 is located between the output filter capacitor C4 and the inverter module 500, and includes a voltage regulator tube Z1, an absorption capacitor C5 and an absorption resistor R1. One end of the output filter capacitor C4 is connected to the cathode of the voltage regulator tube Z1, the anode of the voltage regulator tube Z1 is connected to one end of the absorption capacitor C5 and one end of the absorption resistor R1, and the other end of the absorption capacitor C5 and the other end of the absorption resistor R1 are both connected to the other end of the output filter capacitor C4.

[0051] According to the three-phase BUCK active PFC circuit provided by the embodiment of the utility model, the three-phase AC power supply is supplied to the rear-end load after passing through the input filter module 100, the rectifier module 200, the output filter module 300 and the inverter module 500 in sequence, wherein the output filter module 300 uses a non-electrolytic capacitor as the output filter capacitor C4, and a voltage absorption module 400 is arranged between the output filter capacitor C4 and the inverter module 500. When the induced electromotive force generated by the sudden shutdown of the load causes the voltage across the output filter capacitor C4 to reach the breakdown voltage of the voltage regulator tube Z1, The voltage zener tube Z1 is broken down, the absorption capacitor C5 is charged, and the induced electromotive force is absorbed by the absorption capacitor C5 and the absorption resistor R1 in the voltage absorption module 400, thereby stabilizing the voltage across the output filter capacitor C4; therefore, in the three-phase BUCK active PFC circuit, the output filter capacitor C4 will not be impacted by the abnormal voltage. When the circuit works normally, the voltage zener tube Z1 is not broken down, the absorption resistor R1 will consume the energy of the absorption capacitor C5, the absorption capacitor C5 is not charged, does not need to withstand a large ripple current, has low heat generation, and the entire circuit has high reliability and stability.

[0052] Reference Figure 2 As shown, Figure 2 It is the waveform of the bus voltage Vout outputted by the output filter module 300 to the inverter module 500 during normal driving. Figure 2 When the A-phase drive signal, the B-phase drive signal and the C-phase drive signal shown respectively control the on and off of the bidirectional controllable switch SA, the bidirectional controllable switch SB and the bidirectional controllable switch SC, the output voltage Vpn of the DC output end of the rectifier module 200 is as shown in the figure. At this time, the bus voltage Vout output by the output filter module 300 to the inverter module 500 is relatively stable.

[0053] Reference Figure 3 As shown, Figure 3 When the motor load carried by the inverter module 500 suddenly stops, if the voltage absorption module 400 is not provided, the waveform of the bus voltage Vout output by the output filter module 300 to the inverter module 500 is shown. It can be seen that at the moment of stopping, due to the inertia of the motor rotor, the motor rotor will continue to rotate to generate an induced electromotive force, which charges the output filter capacitor C4, thereby causing the voltage to suddenly increase.

[0054] Further references Figure 4 , Figure 4 For this application Figure 1The three-phase BUCK active PFC circuit shown shows the waveform of the bus voltage Vout output by the output filter module 300 to the inverter module 500 when the motor load carried by the inverter module 500 suddenly stops. It can be seen that when the bus voltage Vout reaches the clamping voltage Vclamp, the voltage regulator tube Z1 is broken down, and the absorption capacitor C5 of the voltage absorption module 400 and the back electromotive force of the motor are absorbed by the electrolytic capacitor, thereby stabilizing the bus voltage Vout; in addition, during normal operation, since the absorption resistor R1 in the voltage absorption module 400 consumes energy, the electrolytic capacitor of the voltage absorption module 400, that is, the absorption capacitor C5, is not charged.

[0055] Reference Figure 5 In the three-phase BUCK active PFC circuit provided in some embodiments of the present invention, the voltage absorption module 400 includes a plurality of voltage regulator tubes Z1, and the plurality of voltage regulator tubes Z1 are connected in series.

[0056] It is understandable that different designs of the clamping voltage Vclamp can be achieved by adjusting the number of the voltage regulator tubes Z1 connected in series.

[0057] Reference Figure 6 In the three-phase BUCK active PFC circuit provided in some embodiments of the present utility model, the output filter module 300 also includes a second output filter inductor L5, that is, the output filter module 300 includes a first output filter inductor L4, a first output filter capacitor C4 and a second output filter inductor L5 at the same time, and the first output filter inductor L4, the output filter capacitor C4 and the second output filter inductor L5 are connected in sequence. Specifically, the positive electrode of the DC output terminal of the rectifier module 200 is connected to one end of the first output filter inductor L4, the other end of the first output filter inductor L4 is connected to one end of the first output filter capacitor C4, the other end of the first output filter capacitor C4 is connected to one end of the second output filter inductor L5, and the other end of the second output filter inductor L5 is connected to the negative electrode of the DC output terminal of the rectifier module 200.

[0058] In addition, it can be understood that there are multiple implementations of the bidirectional controllable switch. In the three-phase BUCK active PFC circuit provided in some embodiments of the present invention, the implementation of the bidirectional controllable switch includes the following cases:

[0059] Case 1: comprising a first switch tube Q1 and a second switch tube Q2 connected in series, the first switch tube Q1 and the second switch tube Q2 are turned on in opposite directions and are respectively provided with anti-parallel diodes; for example, referring to Figure 7a As shown;

[0060] Case 2: including a forward conducting branch and a reverse conducting branch connected in parallel, the forward conducting branch includes a third switch tube Q3 and a seventh diode D7 connected in series, and the reverse conducting branch includes a fourth switch tube Q4 and an eighth diode D8 connected in series; for example, referring to Figure 7b and Figure 7c As shown; it can be understood that Figure 7b The positions of the third switch tube Q3 and the seventh diode D7 in the bidirectional controllable switch shown in FIG. 1 are interchanged, and the positions of the fourth switch tube Q4 and the eighth diode D8 are interchanged, so as to obtain Figure 7c The bidirectional controllable switch shown;

[0061] Case 3: The fourth bridge arm is formed by the ninth diode D9 and the tenth diode D10 connected in series, the fifth bridge arm is formed by the eleventh diode D11 and the twelfth diode D12 connected in series, and the sixth bridge arm is formed by the fifth switch Q5. The fourth bridge arm, the fifth bridge arm and the sixth bridge arm are connected in parallel. For example, referring to Figure 7d As shown;

[0062] Case 4: Including RB-IGBT devices, such as reference Figure 7e shown.

[0063] It should be noted that the above four situations are examples of some feasible implementation methods of the bidirectional controllable switch, and the bidirectional controllable switch of the invention is not limited to only the above four implementation methods. Any other circuit with bidirectional opening and closing controllable functions can be used, as long as the bidirectional opening and closing controllable between the input filter module 100 and the rectifier module can be achieved.

[0064] Reference Figure 1 , Figure 5 and Figure 6 In the three-phase BUCK active PFC circuit provided in some embodiments of the present invention, a freewheeling diode D13 is also included, the positive electrode of the freewheeling diode D13 is connected to the negative electrode of the DC output terminal of the rectifier module 200, and the negative electrode of the freewheeling diode D13 is connected to the positive electrode of the DC output terminal of the rectifier module 200.

[0065] It is understandable that the freewheeling diode D13 is provided so that when the three bidirectional controllable switches are turned off, the output filter module 300 can be freewheeling through the freewheeling diode D13, thereby eliminating the need for freewheeling through the rectifier module 200. Compared with freewheeling through the rectifier module 200, the freewheeling circuit through the freewheeling diode D13 is shorter and has lower loss.

[0066] In addition, the second embodiment of the present invention provides a circuit board, including the three-phase BUCK active PFC circuit of the first embodiment, for example, including Figure 1 , Figure 5 or Figure 6 Any three-phase BUCK active PFC circuit.

[0067] According to the circuit board provided by the embodiment of the utility model, the three-phase AC power supply is supplied to the rear-end load after passing through the input filter module 100, the rectifier module 200, the output filter module 300 and the inverter module 500 in sequence, wherein the output filter module 300 adopts a non-electrolytic capacitor as the output filter capacitor C4, and a voltage absorption module 400 is arranged between the output filter capacitor C4 and the inverter module 500. When the induced electromotive force generated by the sudden shutdown of the load causes the voltage across the output filter capacitor C4 to reach the breakdown voltage of the voltage regulator tube Z1, the voltage regulator tube Z1 The induced electromotive force is absorbed by the absorption capacitor C5 and the absorption resistor R1 in the voltage absorption module 400, thereby stabilizing the voltage across the output filter capacitor C4. Therefore, in the three-phase BUCK active PFC circuit, the output filter capacitor C4 will not be impacted by the abnormal voltage. When the circuit works normally, the voltage regulator tube Z1 is not broken down, the absorption resistor R1 will consume the energy of the absorption capacitor C5, the absorption capacitor C5 is not charged, does not need to withstand a large ripple current, has low heat generation, and the entire circuit has high reliability and stability.

[0068] In addition, a third aspect of the present invention provides a controller, comprising the circuit board of the second aspect of the present invention.

[0069] In addition, a fourth aspect of the present invention provides an air conditioner, comprising the circuit board of the second aspect or the controller of the third aspect.

[0070] It will be appreciated by those skilled in the art that all or some of the steps and systems in the disclosed methods above may be implemented as software, firmware, hardware and appropriate combinations thereof. Some physical components or all physical components may be implemented as software executed by a processor, such as a central processing unit, a digital signal processor or a microprocessor, or implemented as hardware, or implemented as an integrated circuit, such as an application specific integrated circuit. Such software may be distributed on a computer-readable medium, which may include a computer storage medium or a non-transitory medium and a communication medium or a temporary medium. As known to those skilled in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information such as computer-readable instructions, data structures, program modules or other data. Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disk DVD or other optical disk storage, magnetic cassettes, magnetic tapes, disk storage or other magnetic storage devices, or any other medium that may be used to store desired information and may be accessed by a computer. Furthermore, it is well known to those skilled in the art that communication media typically embodies computer readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism, and may include any information delivery media.

[0071] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Various changes can be made within the knowledge scope of ordinary technicians in the technical field without departing from the purpose of the present invention.

Claims

1. A three-phase BUCK active PFC circuit, characterized in that: include: An input filter module is connected to a three-phase AC power supply; A rectifier module connected to the input filter module; An output filter module, comprising a first output filter inductor and an output filter capacitor connected in series, wherein the output filter module is connected to the DC output terminal of the rectifier module; the output filter capacitor is a non-electrolytic capacitor; An inverter module connected to both ends of the output filter capacitor; The voltage absorption module is located between the output filter capacitor and the inverter module, and includes a voltage regulator, an absorption capacitor and an absorption resistor. One end of the output filter capacitor is connected to the cathode of the voltage regulator, the anode of the voltage regulator is connected to one end of the absorption capacitor and one end of the absorption resistor, and the other end of the absorption capacitor and the other end of the absorption resistor are both connected to the other end of the output filter capacitor.

2. The three-phase BUCK active PFC circuit according to claim 1, characterized in that: The voltage absorption module includes a plurality of voltage regulator tubes, and the plurality of voltage regulator tubes are connected in series.

3. The three-phase BUCK active PFC circuit according to claim 1, characterized in that: The output filter module further includes a second output filter inductor, and the first output filter inductor, the output filter capacitor and the second output filter inductor are connected in sequence.

4. The three-phase BUCK active PFC circuit according to claim 1, characterized in that: The rectifier module includes a first bridge arm formed by a first diode and a second diode connected in series, a second bridge arm formed by a third diode and a fourth diode connected in series, a third bridge arm formed by a fifth diode and a sixth diode connected in series, and three bidirectional controllable switches, the first bridge arm, the second bridge arm and the third bridge arm are connected in parallel to each other, the input filter module is respectively connected to one end of the three bidirectional controllable switches, and the other ends of the three bidirectional controllable switches are respectively connected to the midpoint of the first bridge arm, the midpoint of the second bridge arm and the midpoint of the third bridge arm.

5. The three-phase BUCK active PFC circuit according to claim 4, characterized in that: The implementation of the bidirectional controllable switch includes the following cases: Case 1: comprising a first switch tube and a second switch tube connected in series, the first switch tube and the second switch tube have opposite conduction directions and are respectively provided with anti-parallel diodes; Case 2: comprising a forward conducting branch and a reverse conducting branch connected in parallel, wherein the forward conducting branch comprises a third switch tube and a seventh diode connected in series, and the reverse conducting branch comprises a fourth switch tube and an eighth diode connected in series; Case 3: comprising a fourth bridge arm formed by a ninth diode and a tenth diode connected in series, a fifth bridge arm formed by an eleventh diode and a twelfth diode connected in series, and a sixth bridge arm formed by a fifth switch tube, wherein the fourth bridge arm, the fifth bridge arm and the sixth bridge arm are connected in parallel to each other; Case 4: Including RB-IGBT devices.

6. The three-phase BUCK active PFC circuit according to claim 1, characterized in that: The input filter module includes three input filter inductors and three input filter capacitors; one end of the three input filter inductors is respectively connected to a three-phase AC power supply, and the other end is respectively connected to one end of the three input filter capacitors; the other ends of the three input filter capacitors are connected together.

7. The three-phase BUCK active PFC circuit according to claim 1, characterized in that: It also includes a freewheeling diode, the positive electrode of the freewheeling diode is connected to the negative electrode of the DC output terminal of the rectifier module, and the negative electrode of the freewheeling diode is connected to the positive electrode of the DC output terminal of the rectifier module.

8. A circuit board, characterized in that: A three-phase BUCK active PFC circuit comprising any one of claims 1 to 7.

9. A controller, characterized in that: Including the circuit board described in claim 8.

10. An air conditioner, characterized in that: Includes the circuit board described in claim 8 or includes the controller described in claim 9.

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