Totem pole power factor correction circuit, control method, device and equipment

Abstract

The present invention discloses a totem pole power factor correction circuit, control method, device, and equipment. The circuit includes a rectifier module, a reactor, a capacitor module, a control module, and a switch module. The input end of the rectifier module is connected to an AC power source, and the output end of the rectifier module is used to connect to a load; the capacitor module is connected to the output end and includes a first capacitor and a second capacitor connected in series; the switch module is connected to the input end and a first connection point between the first capacitor and the second capacitor; by setting the control module, the rectifier module and the switch module can be controlled according to the load parameters, so that the totem pole power factor correction circuit switches to a synchronous rectification mode or a multi-pulse mode, so that the totem pole power factor correction circuit can meet the load requirements and ensure circuit efficiency when the load parameters change, thereby ensuring the driving effect of the totem pole power factor correction circuit. The present invention can be widely applied in the field of control technology.

Description

Technical Field

[0001] The present invention relates to the field of control technology, and in particular to a totem pole power factor correction circuit, control method, device and equipment. Background Art

[0002] In existing electronic power technology, PFC (Power Factor Correction) circuits are often used to provide bus voltage to achieve a higher power factor. However, some existing totem-pole PFC circuits have a voltage-boosting function, meaning the output voltage of the power factor correction circuit is higher than the input voltage. However, when a voltage doubler (i.e., an output voltage twice the input voltage) is required, or when the load demand exceeds the voltage doubler requirement, these circuits cannot meet the load's requirements. Consequently, existing totem-pole PFC circuits cannot achieve the desired driving effect. Summary of the Invention

[0003] The embodiments of the present application provide a totem pole power factor correction circuit, a control method, an apparatus, and an equipment, which can ensure the driving effect of the totem pole power factor correction circuit.

[0004] According to a first aspect of an embodiment of the present application, a totem pole power factor correction circuit is provided, comprising:

[0005] A rectifier module, comprising an input end and an output end, wherein the input end is connected to an AC power source, and the output end is used to connect to a load;

[0006] A reactor is provided between the rectifier module and the AC power supply;

[0007] a capacitor module connected to the output end, the capacitor module including a first capacitor and a second capacitor, the first capacitor and the second capacitor are connected in series, and the capacitor module is connected in parallel to the output end;

[0008] a switch module, one end of the switch module being connected to a first connection point between the first capacitor and the second capacitor, and the other end of the switch module being connected to the input end;

[0009] The control module is used to control the rectifier module and the switch module according to the load parameters of the load, so that the totem pole power factor correction circuit switches to a synchronous rectification mode or a multi-pulse mode.

[0010] In an embodiment of the present application, the control module can control the rectifier module and the switch module according to the load parameters, so that the totem pole power factor correction circuit switches to a synchronous rectification mode or a multi-pulse mode, so that the totem pole power factor correction circuit can meet the load requirements and ensure the circuit efficiency when the load parameters change, thereby ensuring the driving effect of the totem pole power factor correction circuit.

[0011] In addition, the totem pole power factor correction circuit according to the above embodiment of the present application may also have the following additional technical features:

[0012] The rectifier module includes a bridge circuit, and the bridge circuit includes a first switch unit, a second switch unit, a third switch unit and a fourth switch unit;

[0013] The first switch unit and the second switch unit are connected in series to form a first branch, the third switch unit and the fourth switch unit are connected in series to form a second branch, and the first branch and the second branch are connected in parallel to form the bridge circuit;

[0014] A second connection point between the first switch unit and the third switch unit is connected to the first end of the first capacitor, a second end of the first capacitor is connected to the first end of the second capacitor, and a third connection point between the second switch unit and the fourth switch unit is connected to the second end of the second capacitor;

[0015] A fourth connection point between the first switch unit and the second switch unit is connected to one end of the AC power supply, a fifth connection point between the third switch unit and the fourth switch unit is connected to the other end of the AC power supply, and the fifth connection point is connected to the second end of the first capacitor through the switch module;

[0016] The reactor is provided between the fourth connection point and the AC power source, or between the fifth connection point and the AC power source.

[0017] In the embodiment of the present application, the rectification effect of the rectifier module can be ensured by setting a bridge circuit, and the control in the synchronous rectification mode and the multi-pulse mode can be realized by setting a switch module.

[0018] Optionally, in one embodiment of the present application, the rectifier module further includes a first power diode and a second power diode;

[0019] The anode of the first power diode is connected to the second connection point, the cathode of the first power diode is connected to the first end of the first capacitor, the anode of the second power diode is connected to the second end of the second capacitor, and the cathode of the power diode is connected to the third connection point.

[0020] In an embodiment of the present application, by setting the first power diode and the second power diode, backflow can be prevented when the input voltage of the rectifier module is lower than the bus voltage, thereby protecting the totem pole power factor correction circuit; when the switch module is in a normally closed state, backflow can be prevented when the first capacitor and the second capacitor are discharged.

[0021] Optionally, in one embodiment of the present application, the switch module includes a relay or a switch tube unit;

[0022] The switch tube unit includes a fifth diode, a sixth diode, a seventh diode, an eighth diode and a first switch tube, the fifth diode and the sixth diode are connected in series to form a first diode branch, the seventh diode and the eighth diode are connected in series to form a second diode branch, the first switch tube, the first diode branch and the second diode branch are connected in parallel, the connection point between the fifth diode and the sixth diode is led out as one end of the switch module, and the connection point between the seventh diode and the eighth diode is led out as the other end of the switch module;

[0023] Or the switch tube unit includes a second switch tube and a third switch tube connected in reverse parallel;

[0024] Alternatively, the switch tube unit includes a fourth switch tube and a fifth switch tube connected in reverse series, and both the fourth switch tube and the fifth switch tube are anti-parallel connected with a diode.

[0025] In an embodiment of the present application, the switch module provides a variety of types and has strong applicability. When the switch module is a relay, the presence of the first power diode and the second power diode can prevent the first capacitor and the second capacitor from backflowing during discharge.

[0026] According to a second aspect of an embodiment of the present application, a control method is provided, which is applied to the totem pole power factor correction circuit of the above embodiment. The control method includes the following steps:

[0027] Obtaining the load parameters;

[0028] Determining that the load parameter is greater than or equal to a first threshold and less than a second threshold, and controlling the totem pole power factor correction circuit to switch to a synchronous rectification mode;

[0029] Alternatively, it is determined that the load parameter is greater than or equal to a second threshold and less than a third threshold, and the totem pole power factor correction circuit is controlled to switch to a multi-pulse mode.

[0030] In the embodiment of the present application, it is determined that the load parameter is greater than or equal to a first threshold and less than a second threshold, and the totem pole power factor correction circuit is controlled to switch to a synchronous rectification mode, which can achieve voltage doubling and reduce switching losses of the rectifier module, thereby improving circuit efficiency;

[0031] Determine that the load parameter is greater than or equal to the second threshold and less than the third threshold, control the totem pole power factor correction circuit to switch to a multi-pulse mode, which can achieve voltage doubling and further increase the bus voltage, ensure circuit efficiency and meet load requirements.

[0032] Optionally, in one embodiment of the present application, controlling the totem pole power factor correction circuit to switch to a synchronous rectification mode comprises the following steps:

[0033] Determining that the input voltage of the bridge circuit is in a first time period of a positive half cycle, controlling the first switch unit and the switch module to be turned on, and controlling the second switch unit, the third switch unit, and the fourth switch unit to be turned off;

[0034] Determine that the input voltage of the bridge circuit is in a second time period of a negative half cycle, control the second switch unit and the switch module to be turned on, and control the first switch unit, the third switch unit, and the fourth switch unit to be turned off.

[0035] In an embodiment of the present application, different controls are implemented on the first switch unit and the second switch unit according to whether the input voltage is in the positive half cycle or the negative half cycle, effectively ensuring that the totem pole power factor correction circuit switches to the synchronous rectification mode.

[0036] Optionally, in one embodiment of the present application, controlling the totem pole power factor correction circuit to switch to a multi-pulse mode comprises the following steps:

[0037] determining that the input voltage of the bridge circuit is in a positive half cycle, and controlling the bridge circuit and the switch module to charge and discharge the reactor several times and charge the first capacitor during the positive half cycle;

[0038] It is determined that the input voltage of the bridge circuit is in a negative half cycle. In the negative half cycle, the bridge circuit and the switch module are controlled to charge and discharge the reactor several times and charge the second capacitor.

[0039] In an embodiment of the present application, by controlling the bridge circuit and the switching module to charge and discharge the reactor several times, the bus voltage can be increased, and the magnitude, frequency and phase of the output current of the rectifier module can be controlled to offset the harmonics in the load current and realize compensation of dynamic reactive current.

[0040] Optionally, in one embodiment of the present application, the rectifier module further includes a first power diode and a second power diode, wherein the anode of the first power diode is connected to the second connection point, the cathode of the first power diode is connected to the first end of the first capacitor, the anode of the second power diode is connected to the second end of the second capacitor, and the cathode of the power diode is connected to the third connection point;

[0041] The controlling the bridge circuit and the switch module to charge and discharge the reactor several times and charge the first capacitor comprises the following steps:

[0042] Controlling the first switch unit and the switch module to be turned on, controlling the second switch unit and the fourth switch unit to be turned off, and controlling the third switch unit to be turned on and off several times within a preset time;

[0043] Or control the third switch unit to turn off and control the switch module to turn on, and perform the first switch control on the first switch unit, the second switch unit and the fourth switch unit several times within a preset time; control the first switch unit to turn on and control the second switch unit and the fourth switch unit to turn off after the preset time; during the first switch control process, the switching states of the second switch unit and the fourth switch unit are the same, and the switching state of the second switch unit is opposite to that of the first switch unit.

[0044] In an embodiment of the present application, different control means are provided for the first switch unit, the second switch unit, the third switch unit, and the fourth switch unit to achieve multi-pulse control and meet different control requirements; wherein, by setting the first power diode and the second power diode, when the switch module is in a normally closed state, backflow of the first capacitor and the second capacitor during discharge can be prevented.

[0045] Optionally, in one embodiment of the present application, controlling the bridge circuit and the switch module to charge and discharge the reactor several times and charge the first capacitor includes the following steps:

[0046] Controlling the third switch unit to turn off, and performing a second switch control on the first switch unit, the second switch unit, the fourth switch unit, and the switch module several times within a preset time; controlling the first switch unit and the switch module to turn on, and controlling the second switch unit and the fourth switch unit to turn off within a period of time after the preset time; during the second switch control process, the second switch unit and the fourth switch unit have the same switch state, the first switch unit and the switch module have the same switch state, and the first switch unit and the second switch unit have opposite switch states;

[0047] Alternatively, the second switch unit and the fourth switch unit are controlled to be turned off, the first switch unit is controlled to be turned on within a preset time, and the third switch control is performed on the third switch unit and the switch module several times; within a period of time after the preset time, the first switch unit is controlled to be turned on, the third switch unit is controlled to be turned off, and the switch module is controlled to be turned on; during the third switch control process, the switching states of the third switch unit and the switch module are opposite.

[0048] In the embodiment of the present application, different control means are provided for the first switch unit, the second switch unit, the third switch unit, the fourth switch unit and the switch module to achieve multi-pulse control to meet different control requirements.

[0049] Optionally, in one embodiment of the present application, the rectifier module further includes a first power diode and a second power diode; the anode of the first power diode is connected to the second connection point, the cathode of the first power diode is connected to the first end of the first capacitor, the anode of the second power diode is connected to the second end of the second capacitor, and the cathode of the power diode is connected to the third connection point;

[0050] The controlling the bridge circuit and the switch module to charge and discharge the reactor several times and charge the second capacitor comprises the following steps:

[0051] Controlling the second switch unit and the switch module to be turned on, controlling the first switch unit and the third switch unit to be turned off, and controlling the fourth switch unit to be turned on and off several times within a preset time;

[0052] Or the fourth switch unit is controlled to be turned off and the switch module is controlled to be turned on, and the fourth switch control is performed on the first switch unit, the second switch unit and the third switch unit several times within a preset time; after the preset time, the first switch unit and the third switch unit are controlled to be turned off, and the second switch unit is controlled to be turned on; during the fourth switch control process, the switching states of the first switch unit and the third switch unit are the same, and the switching states of the first switch unit and the second switch unit are opposite.

[0053] In an embodiment of the present application, different control means are provided for the first switch unit, the second switch unit, the third switch unit, and the fourth switch unit to achieve multi-pulse control and meet different control requirements. Specifically, by setting the first power diode and the second power diode, when the switch module is in a normally closed state, backflow of the first capacitor and the second capacitor during discharge can be prevented.

[0054] Optionally, in one embodiment of the present application, controlling the bridge circuit and the switch module to charge and discharge the reactor several times and charge the second capacitor includes the following steps:

[0055] Controlling the fourth switch unit to turn off, and performing a fifth switch control on the first switch unit, the third switch unit, the second switch unit, and the switch module several times within a preset time; controlling the second switch unit and the switch module to turn on, and controlling the first switch unit and the third switch unit to turn off within a period of time after the preset time; during the fifth switch control process, the first switch unit and the third switch unit have the same switch state, the second switch unit and the switch module have the same switch state, and the first switch unit and the second switch unit have opposite switch states;

[0056] Alternatively, the first switch unit and the third switch unit are controlled to be turned off, the second switch unit is controlled to be turned on within a preset time, and the sixth switch control is performed on the fourth switch unit and the switch module several times; within a period of time after the preset time, the second switch unit is controlled to be turned on, the fourth switch unit is controlled to be turned off, and the switch module is controlled to be turned on; during the sixth switch control process, the switching states of the fourth switch unit and the switch module are opposite.

[0057] In the embodiment of the present application, different control means are provided for the first switch unit, the second switch unit, the third switch unit, the fourth switch unit and the switch module to achieve multi-pulse control to meet different control requirements.

[0058] Optionally, in one embodiment of the present application, the following steps are further included:

[0059] The number of times the reactor is charged and discharged is controlled according to the load parameter.

[0060] In the embodiment of the present application, the number of times the reactor is charged and discharged can be controlled according to the size of the load parameters, thereby controlling the increase in the bus voltage to meet the load demand.

[0061] Optionally, in one embodiment of the present application, the load parameter includes at least one of load current, load power, load operating pressure and load frequency.

[0062] In the embodiment of the present application, it may include at least one of load current, load power, load operating pressure and load frequency, which is diversified and can meet different needs of actual conditions.

[0063] According to a third aspect of an embodiment of the present application, there is provided an apparatus, including:

[0064] at least one processor;

[0065] at least one memory for storing at least one program;

[0066] When the at least one program is executed by the at least one processor, the at least one processor implements the control method described in the second aspect.

[0067] According to a fourth aspect of the embodiments of the present application, a device is provided, including:

[0068] load;

[0069] The load is driven by the device described in the third aspect.

[0070] According to a fifth aspect of an embodiment of the present application, a storage medium is provided, wherein the storage medium stores a program, and the program is used to implement the control method described in the second aspect when executed by a processor.

[0071] Through the technical solution provided in the embodiments of the present application, it is possible to switch to the synchronous rectification mode to achieve voltage doubling according to the load parameters, reduce losses (such as switching losses of the rectifier module) and improve circuit efficiency while meeting the load requirements; and it is possible to switch to the multi-pulse mode to achieve voltage doubling according to the load parameters, and further improve the ability to drive the load (such as increasing the bus voltage) to meet higher load requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] Figure 1 A schematic diagram of a totem pole power factor correction circuit provided in an embodiment of the application;

[0073] FIG2( a ) shows a first implementation of a switch tube unit, FIG2( b ) shows a second implementation of a switch tube unit, and FIG2( c ) shows a third implementation of a switch tube unit;

[0074] Figure 3 A schematic diagram of another totem pole power factor correction circuit provided in an embodiment of the application;

[0075] Figure 4 A flow chart of a control method provided in an embodiment of the application;

[0076] Figure 5 This is a pulse diagram of the first control method for the rectifier module and the switch module in the embodiment of the application;

[0077] Figure 6 This is a pulse diagram of the second control method for the rectifier module and the switch module in the embodiment of the application;

[0078] Figure 7A pulse diagram of the third control method for the rectifier module and the switch module in the embodiment of the application;

[0079] Figure 8 A pulse diagram of the fourth control method for the rectifier module and the switch module in the embodiment of the application;

[0080] Figure 9 This is a schematic diagram of a device in an application embodiment. DETAILED DESCRIPTION

[0081] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0082] Reference Figure 1 A totem pole power factor correction circuit is provided in an embodiment of the present application. The totem pole power factor correction circuit includes a rectifier module 10, an inductor L, a capacitor module 20, a control module 30 and a switch module.

[0083] The rectifier module 10 includes an input end and an output end. The input end is connected to an alternating current power source AC, and the output end is connected to a load.

[0084] The reactor L is provided between the rectifier module 10 and the AC power source AC. One end of the reactor L is connected to the AC power source AC, and the other end of the reactor L is connected to the input end of the rectifier module 10 .

[0085] The capacitor module 20 is connected in parallel with the output end of the rectifier module 10. The capacitor module 20 includes a first capacitor C1 and a second capacitor C2. The first capacitor C1 and the second capacitor C2 are connected in series. The first connection point a between the first capacitor C1 and the second capacitor C2 is connected to the input end of the rectifier module 10.

[0086] The control module 30 is used to control the rectifier module 10 and the switch module according to the load parameters of the load, so that the totem pole power factor correction circuit switches to the synchronous rectification mode or the multi-pulse mode, so that the totem pole power factor correction circuit can meet the load requirements and ensure circuit efficiency when the load parameters change, thereby ensuring the driving effect of the totem pole power factor correction circuit.

[0087] In this embodiment, the rectifier module 10 may specifically include a bridge circuit, which includes a first switch unit 11, a second switch unit 12, a third switch unit 13, and a fourth switch unit 14. The first switch unit 11 and the second switch unit 12 are connected in series to form a first branch, the third switch unit 13 and the fourth switch unit 14 are connected in series to form a second branch, and the first branch and the second branch are connected in parallel to form a bridge circuit.

[0088] A second connection point b between the first switch unit 11 and the third switch unit 13 is connected to a first end of the first capacitor C1, a second end of the first capacitor C1 is connected to a first end of the second capacitor C2, and a third connection point c between the second switch unit 12 and the fourth switch unit 14 is connected to a second end of the second capacitor C2;

[0089] A fourth connection point d between the first switch unit 11 and the second switch unit 12 is connected to one end of the AC power source AC, a fifth connection point e between the third switch unit 13 and the fourth switch unit 14 is connected to the other end of the AC power source AC, and the fifth connection point e is connected to the second end of the first capacitor C1;

[0090] The first switch unit 11 includes a first power tube Q1 and a first diode D1 anti-parallel to the first power tube Q1, the second switch unit 12 includes a second power tube Q2 and a second diode D2 anti-parallel to the second power tube Q2, the third switch unit 13 includes a third power tube Q3 and a third diode D3 anti-parallel to the third power tube Q3, and the fourth switch unit 14 includes a fourth power tube Q4 and a fourth diode D4 anti-parallel to the fourth power tube Q4;

[0091] In this embodiment, the fifth connection point e is connected to the second end of the first capacitor C1 via a switch module Q5. The switch module Q5 has a bidirectional conduction function and is disposed between the first connection point a and the fifth connection point e. Specifically, one end of the switch module Q5 is connected to the fifth connection point e (i.e., connected to one of the input terminals of the rectifier module), and the other end of the switch module Q5 is connected to the second end of the first capacitor, i.e., the first connection point a. The configuration of the switch module Q5 enables control in both synchronous rectification and multi-pulse modes, and can also switch the totem pole power factor correction circuit to a general operating mode other than the voltage doubling mode. For example, the switch module Q5 is turned off when the input voltage of the bridge circuit is in both the positive and negative half-cycles.

[0092] Optionally, in this embodiment, the switch module Q5 includes but is not limited to multiple implementations, such as a relay or a switch tube unit, wherein the switch tube unit includes but is not limited to one of the following implementations:

[0093] 1) As shown in FIG2(a), the switch tube unit includes a fifth diode D7, a sixth diode D8, a seventh diode D9, an eighth diode D10, and a first switch tube Q6. The fifth diode D7 and the sixth diode D8 are connected in series to form a first diode branch. The seventh diode D9 and the eighth diode D10 are connected in series to form a second diode branch. The first switch tube Q6, the first diode branch, and the second diode branch are connected in parallel. The connection point between the fifth diode D7 and the sixth diode D8 is connected as one end of the switch module, and the connection point between the seventh diode D9 and the eighth diode D10 is connected as the other end of the switch module. When the switch module is turned on, the first switch tube Q6 is turned on, and when the switch module is turned off, the first switch tube Q6 is turned off.

[0094] 2) As shown in FIG2(b), the switch tube unit includes a second switch tube Q7 and a third switch tube Q8 connected in anti-parallel. When the switch module is turned on, the second switch tube Q7 is turned on and the third switch tube Q8 is turned off, or the second switch tube Q7 is turned off and the third switch tube Q8 is turned on. When the switch module is turned off, both the second switch tube Q7 and the third switch tube Q8 are turned off.

[0095] 3) As shown in FIG2(c), the switch tube unit includes a fourth switch tube Q9 and a fifth switch tube Q10 connected in reverse series, and each of the fourth switch tube Q9 and the fifth switch tube Q10 is anti-parallel-connected with a diode (a ninth diode D11 and a tenth diode D12, respectively). When the switch module is turned on, the fourth switch tube Q9 is turned on and the fifth switch tube Q10 is turned off, or the fourth switch tube Q9 is turned off and the fifth switch tube Q10 is turned on. When the switch module is turned off, both the fourth switch tube Q9 and the fifth switch tube Q10 are turned off.

[0096] It is understandable that in other embodiments, the rectifier module 10 is not limited to the above structure and can be flexibly selected and set; the first power tube Q1, the second power tube Q2, the third power tube Q3 and the fourth power tube Q4 include but are not limited to metal oxide semiconductor field effect transistors (MOSFETs), insulated gate bipolar transistors (IGBTs), gallium nitride (GaN) power transistors, SiC (silicon carbide) power transistors, etc.

[0097] like Figure 1As shown, in this embodiment, the rectifier module 10 further includes a first power diode D5 and a second power diode D6. The second connection point b is connected to the first end of the first capacitor C1 via the first power diode D5, and the third connection point c is connected to the second end of the second capacitor C2 via the second power diode D6. The anode of the first power diode D5 is connected to the second connection point b, the cathode of the first power diode D5 is connected to the first end of the first capacitor C1, the anode of the second power diode D6 is connected to the second end of the second capacitor C2, and the cathode of the second power diode D6 is connected to the third connection point c.

[0098] In the embodiment of the present application, the first power diode D5 and the second power diode D6 are provided to prevent backflow when the input voltage of the rectifier module 10 is lower than the bus voltage, thereby protecting the totem pole power factor correction circuit. Due to the presence of the first power diode D5 and the second power diode D6, the switch module Q5 can be a relay in addition to the above-mentioned switch tube. When the switch module Q5 is a relay, when the relay is in the normally closed state, the first power diode D5 and the second power diode D6 can prevent backflow when the first capacitor C1 and the second capacitor C2 discharge.

[0099] In this embodiment, the input end of the rectifier module 10 includes a first input end and a second input end, and the output end includes a first output end and a second output end; wherein the first input end is the fourth connection point d, the second input end is the fifth connection point e, the first output end is the second connection point b, and the second output end is the third connection point c.

[0100] The reactor L is specifically provided between the fourth connection point d and the AC power source AC. In other embodiments, the reactor L may be provided between the fifth connection point e and the AC power source AC.

[0101] In this embodiment, the control module 30 includes an AC voltage detection unit 31, a current detection unit 32, a control unit 33, and a DC voltage detection unit 34. It can be understood that the control module 30 may also include other detection units (not shown) for obtaining load parameters. For example, the load parameters may include but are not limited to one or more of load current, load power, load operating pressure, and load frequency.

[0102] For example, when the load parameters include load current, the load current can be sampled for the control module 30 to separate the harmonics and reactive power, so that the control module 30 controls the on and off of the rectifier module and the energy storage and release of the reactor, thereby actively controlling the magnitude, frequency and phase of the output current of the rectifier module, and responding quickly to offset the corresponding harmonics in the load, and realizing dynamic tracking and compensation of reactive current, which can compensate for both harmonics and reactive current.

[0103] The current detection unit 32 is electrically connected to the input end of the rectifier module 10 and is used to detect the input current Is of the rectifier module 10 , that is, the input current Is of the bridge circuit.

[0104] The AC voltage detection unit 31 is electrically connected to the input end of the rectifier module 10 and is used to detect the input voltage of the input end of the rectifier module 10 (ie, the voltage Us of the AC power supply VC).

[0105] The DC voltage detection unit 34 is electrically connected to the input terminal of the load and is used to detect the bus voltage of the load, that is, the required voltage of the load.

[0106] The control unit 33 is connected to the current detection unit 32, the intersection voltage detection unit and the DC voltage detection unit 34, and can be further connected to other detection units. It is used to control the on and off states of the rectifier module and the switch module Q5 according to the load parameters, so that the totem pole power factor correction circuit switches to the synchronous rectification mode or the multi-pulse mode.

[0107] In this embodiment, the totem pole power factor correction circuit operates in the voltage doubling mode to realize the voltage doubling function, that is, the bus voltage connected to the load is twice the input voltage of the rectifier module 10, among which the synchronous rectification mode and the multi-pulse mode are two working modes under the voltage doubling mode. In the multi-pulse mode, the energy storage and release of the inductor L are realized by multiple conduction and shutdown of the first switch unit 11, the second switch unit 12, the third switch unit 13, the fourth switch unit 14 and the switch module Q5, so as to achieve further boosting under voltage doubling and increase the bus voltage.

[0108] like Figure 3 As shown, it is understood that in some other embodiments, the rectifier module 10 may not be provided with the first power diode D5 and the second power diode D6, the second connection point b may be connected to the first end of the first capacitor C1 via a wire, and the third connection point c may be connected to the second end of the second capacitor C2 via a wire. It is understood that the corresponding switch module Q5 is configured in the form of the above-mentioned switch tube unit.

[0109] Reference Figure 4 , an embodiment of the present application further provides a control method applied to a totem pole power factor correction circuit, comprising the following steps:

[0110] S1. Obtain load parameters;

[0111] S2. Determine that the load parameter is greater than or equal to a first threshold and less than a second threshold, and control the totem pole power factor correction circuit to switch to a synchronous rectification mode;

[0112] or,

[0113] It is determined that the load parameter is greater than or equal to the second threshold and less than the third threshold, and the totem pole power factor correction circuit is controlled to switch to the multi-pulse mode.

[0114] The totem pole power factor correction circuit is the totem pole power factor correction circuit in the above embodiment.

[0115] In this embodiment, the load parameters include at least one of load current, load power, load operating pressure, and load frequency. The load operating pressure and load frequency are specific operating pressures and frequencies of different load types. For example, if the load includes a compressor, the load operating pressure is the compressor operating pressure, and the load frequency is the compressor frequency. The load parameters may include one of load current, load power, load operating pressure, and load frequency. When the load parameters include more than one of these indicators, the load parameters may be determined by calculation based on a combination of these indicators. For example, if the load parameters include load current and load power, the load parameters may be determined by, but are not limited to, the following methods: setting a first weight for the load current and a second weight for the load power, and performing a weighted calculation based on the first weight, the load current, the second weight, and the load power to determine the load parameters. Alternatively, if the load parameters include load current, load power, and load operating pressure, corresponding weights may also be set, and the load parameters may be determined by a weighted calculation. The load parameters may be determined based on the desired indicators and corresponding weights, flexibly adjusted, and the load parameters may be determined based on the desired indicators. Optionally, the parameters of the load actually driven by the totem pole power factor correction circuit may also be determined using, but not limited to, the above methods.

[0116] The first threshold value P1, the second threshold value P2, and the third threshold value P3 can be reasonably set according to the load parameters and the requirements of the totem pole power factor correction circuit. For example, the load parameter includes the load frequency. When the load frequency is at a first frequency, the load is considered to be low, and the first frequency is used as the first threshold value P1; when the load frequency is at a second frequency, the load is considered to be medium, and the second frequency is used as the second threshold value P2; when the load frequency is at a third frequency, the load is considered to be heavy, and the third frequency is used as the third threshold value P3; or the load parameter includes the load current. When the load current is a first current value, the load is considered to be low, and the first current value is used as the first threshold value P1; when the load current is a second current value, the load is considered to be medium, and the second current value is used as the second threshold value P2; when the load current is a third current value, the load is considered to be heavy, and the third current value is used as the third threshold value P3; wherein the low load, medium load, and heavy load can be reasonably adjusted according to actual needs and actual conditions, and are not specifically limited. When the load parameters include other indicators, they can also be determined using a similar method and can also be reasonably adjusted according to actual needs and actual conditions.

[0117] By controlling the load parameter P (i.e., the parameter of the load actually driven by the totem pole power factor correction circuit), when P1 ≤ P < P2, the circuit switches to a synchronous rectification mode. While meeting the current load demand, the number of switching times and switching losses of the rectifier module are reduced, circuit efficiency is improved, the complexity of the control module 30 is reduced, and costs are saved. When P2 ≤ P < P3, the circuit switches to a multi-pulse mode, increasing the bus voltage, which can meet higher load demands and harmonic demands, and improve the APF (annual energy consumption efficiency). It can be imagined that when P2 ≤ P < P3, the synchronous rectification mode will not be able to meet the load demand, resulting in the load not being able to operate normally. When P1 ≤ P < P2, the multi-pulse mode is used, and the output voltage of the rectifier module exceeds the voltage required by the load, increasing power loss and increasing the switching loss of the rectifier module 10, resulting in large power loss in the circuit and reducing circuit efficiency. Therefore, the embodiment of the present invention provides a method for switching between a multi-pulse mode and a synchronous rectification mode according to the load parameters, which can ensure circuit efficiency.

[0118] The control method in the embodiment of the present application is described below with reference to the above-mentioned totem pole power factor correction circuit embodiment.

[0119] Reference Figure 1 and Figure 5 , Figure 5 What is shown is a pulse diagram of the first control method for the rectifier module and the switch module in an embodiment of the present application.

[0120] When P1≤P<P2, the totem pole power factor correction circuit is controlled to switch to synchronous rectification mode. The specific control process is as follows:

[0121] When the input voltage Us of the bridge circuit (i.e., the input voltage Us of the rectifier module 10) is in the positive half cycle, the switch module Q5 is controlled to be turned on. When the input voltage Us crosses the zero point and there is a delay of a period of time (specifically, within the first time period TA of the positive half cycle), the first switch unit 11 is controlled to be turned on, and the second switch unit 12, the third switch unit 13, and the fourth switch unit 14 are controlled to be turned off, so that the input current passes through the reactor L, the first switch unit 11, the first power diode D5, and the first capacitor C1 to charge the first capacitor C1.

[0122] When the input voltage Us of the bridge circuit is in the negative half cycle, the switch module Q5 is controlled to be turned on. When the input voltage Us passes through zero and there is a delay of a period of time (specifically, within the second time period TB of the negative half cycle), the second switch unit 12 is controlled to be turned on, and the first switch unit 11, the third switch unit 13 and the fourth switch unit 14 are controlled to be turned off, so that the input current passes through the second capacitor C2, the second power diode D6, the second switch unit 12 and the reactor L to charge the second capacitor C2.

[0123] When P2≤P<P3, the totem pole power factor correction circuit is controlled to switch to the multi-pulse mode. The specific control process is as follows:

[0124] When the input voltage Us of the bridge circuit (i.e., the input voltage Us of the rectifier module 10) is in a positive half-cycle, the first switch unit 11 and the switch module Q5 are controlled to be turned on, and the second switch unit 12 and the fourth switch unit 14 are controlled to be turned off during the positive half-cycle. Furthermore, within a preset period of time (specifically, a first preset time T1) within the positive half-cycle, the third switch unit 13 is controlled to be turned on and off several times. In this embodiment, the number of times is four times, and in other embodiments, the number of times can be adjusted as needed. Furthermore, after the first preset time T1, the third switch unit 13 is controlled to be turned off to charge the first capacitor C1.

[0125] Specifically, when the third switch unit 13 is in the on state, the input current passes through the inductor L, the first switch unit 11 and the third switch unit 13, thereby storing energy (charging) the inductor L; and when the third switch unit 13 is in the off state, the input current passes through the inductor L, the first switch unit 11, the first power diode D5 and the first capacitor C1, and the inductor L releases energy (discharges) to charge the first capacitor C1.

[0126] When the input voltage Us of the bridge circuit is in a negative half-cycle, the second switch unit 12 and the switch module Q5 are controlled to be turned on, and the first switch unit 11 and the third switch unit 13 are controlled to be turned off during the negative half-cycle. Furthermore, within a preset period of time (specifically, the second preset time T2) within the negative half-cycle, the fourth switch unit 14 is controlled to be turned on and off several times. In this embodiment, the number of times is four times, and in other embodiments, the number of times can be adjusted as needed. After the second preset time T2, the fourth switch unit 14 is controlled to be turned off to charge the second capacitor C2.

[0127] Specifically, when the fourth switch unit 14 is in the on state, the input current passes through the fourth switch unit 14 and the inductor L to store energy (charge) in the inductor L; and when the fourth switch unit 14 is in the off state, the input current passes through the inductor L, the second switch unit 12, the second power diode D6 and the second capacitor C2, and the inductor L releases energy (discharges) to charge the second capacitor C2.

[0128] If the switch module Q5 is in a normally closed state, the first power diode D5 and the first power diode D6 can prevent the first capacitor C1 and the second capacitor C2 from backflowing during discharge.

[0129] Reference Figure 1 and Figure 6 , Figure 6What is shown is a pulse diagram of the second control method for the rectifier module 10 and the switch module in the embodiment of the present application. The difference from the first control method is the multi-pulse control.

[0130] When P2≤P<P3, the totem pole power factor correction circuit is controlled to switch to the multi-pulse mode. The specific control process is as follows:

[0131] When the input voltage Us of the bridge circuit (i.e., the input voltage Us of the rectifier module 10) is in a positive half-cycle, the third switch unit 13 is controlled to be off and the switch module Q5 is controlled to be on during the positive half-cycle. After the input voltage Us crosses zero, the first switch unit 11 is controlled to be on. Then, within a preset time (specifically, the third preset time T3) within the positive half-cycle, the first switch unit 11, the second switch unit 12, and the fourth switch unit 14 are controlled several times for first switching. Specifically, during the first switching control process, the switching states of the second switch unit 12 and the fourth switch unit 14 are the same, and the switching states of the second switch unit 12 and the first switch unit 11 are opposite. That is, when the first switch unit 11 is on, the second switch unit 12 and the fourth switch unit 14 are off, and when the first switch unit 11 is off, the second switch unit 12 and the fourth switch unit 14 are on. After the third preset time T3, the first switch unit 11 is controlled to be on, and the second switch unit 12 and the fourth switch unit 14 are controlled to be off. The number of first switching controls can be adjusted as needed.

[0132] Specifically, within the third preset time T3, when the first switch unit 11 is turned off and the second switch unit 12 and the fourth switch unit 14 are turned on, the input current passes through the second switch unit 12, the fourth switch unit 14, and the reactor L, thereby storing (charging) the reactor L. When the first switch unit 11 is turned on and the second switch unit 12 and the fourth switch unit 14 are turned off, the input current passes through the reactor L, the first switch unit 11, the first power diode D5, and the first capacitor C1, and the reactor L releases energy (discharges) to charge the first capacitor C1. After the third preset time T3, the first switch unit 11 is controlled to be turned on and the second switch unit 12 and the fourth switch unit 14 are turned off, and the input current passes through the reactor L, the first switch unit 11, the first power diode D5, and the first capacitor C1 to charge the first capacitor C1.

[0133] When the input voltage Us of the bridge circuit (i.e., the input voltage Us of the rectifier module 10) is in a negative half-cycle, during this negative half-cycle, the fourth switch unit 14 is controlled to be off and the switch module Q5 is controlled to be on. After the input voltage Us crosses zero, the second switch unit 12 is controlled to be on. Then, within a preset time (specifically, a fourth preset time T4) within the negative half-cycle, the first switch unit 11, the second switch unit 12, and the third switch unit 13 are subjected to a fourth switching control several times. Specifically, during the fourth switching control process, the switching states of the first switch unit 11 and the third switch unit 13 are the same, and the switching states of the first switch unit 11 and the second switch unit 12 are opposite. That is, when the second switch unit 12 is on, the first switch unit 11 and the third switch unit 13 are off, and when the second switch unit 12 is off, the first switch unit 11 and the third switch unit 13 are on. After the fourth preset time T4, the second switch unit 12 is controlled to be on, and the first switch unit 11 and the third switch unit 13 are controlled to be off. The number of fourth switching controls can be adjusted as needed.

[0134] Specifically, within the fourth preset time T4, when the first switch unit 11 and the third switch unit 13 are turned on and the second switch unit 12 is turned off, the input current passes through the third switch unit 13, the first switch unit 11 and the reactor L to store energy (charge) in the reactor L; when the first switch unit 11 and the third switch unit 13 are turned off and the second switch unit 12 is turned on, the input current passes through the reactor L, the second switch unit 12, the second power diode D6 and the second capacitor C2, and the reactor L releases energy (discharges) to charge the second capacitor C2. After the fourth preset time T4, the second switch unit 12 is controlled to be turned on, the first switch unit 11 and the third switch unit 13 are turned off, and the input current passes through the reactor L, the second switch unit 12, the second power diode D6 and the second capacitor C2 to charge the second capacitor C2.

[0135] If the switch module Q5 is in a normally closed state, the first power diode D5 and the first power diode D6 can prevent the first capacitor C1 and the second capacitor C2 from backflowing during discharge.

[0136] It can be understood that the above-mentioned control of the switch module Q5 to be turned on refers to the switch module Q5 being in the turned-on state. For example, the switch module Q5 can be controlled to be turned on when the input voltage Us of the bridge circuit is in the positive half cycle or when the input voltage Us of the bridge circuit is in the negative half cycle, or the switch module Q5 can be controlled in advance to be turned on. For example, when the switch module Q5 is a relay, the switch module Q5 is in the normally closed state, so that the switch module Q5 is also in the turned-on state when the input voltage Us of the bridge circuit is in the positive half cycle or when the input voltage Us of the bridge circuit is in the negative half cycle.

[0137] Reference Figure 3 and Figure 7 , Figure 7 What is shown is a pulse diagram of the third control method for the rectifier module and the switch module in the embodiment of the present application, wherein the control method of the synchronous rectification method is the same and will not be repeated here.

[0138] When P2≤P<P3, the totem pole power factor correction circuit is controlled to switch to the multi-pulse mode. The specific control process is as follows:

[0139] When the input voltage Us of the bridge circuit (i.e., the input voltage Us of the rectifier module 10) is in a positive half cycle, the third switch unit 13 is controlled to be turned off in the positive half cycle. When the input voltage Us crosses the zero point and then enters a preset time (specifically, the fifth preset time T5) in the positive half cycle, the first switch unit 11, the second switch unit 12, the fourth switch unit 14, and the switch module Q5 are subjected to several second switching controls. Specifically, in the second switching control process, the switching states of the second switch unit 12 and the fourth switch unit 14 are the same. The first switch unit 11 and the switch module Q5 have the same switching state, while the first switch unit 11 and the second switch unit 12 have opposite switching states. That is, when the first switch unit 11 is on, the switch module Q5 is on, and the second switch unit 12 and the fourth switch unit 14 are off. When the first switch unit 11 is off, the switch module Q5 is off, and the second switch unit 12 and the fourth switch unit 14 are on. Within a period of time after the fifth preset time T5, the first switch unit 11 and the switch module Q5 are controlled to be on, and the second switch unit 12 and the fourth switch unit 14 are controlled to be off. The number of times the second switch is controlled can be adjusted as needed.

[0140] Among them, the above-mentioned period of time after the fifth preset time T5 can be adjusted according to actual conditions, and the period of time includes but is not limited to the time from the fifth preset time T5 to the time when the current Is is zero (that is, when it is detected that no current passes through the diode in the first switch unit 11). After this period of time, the first switch unit 11 is turned off, and the switch module Q5 is maintained on, and the second switch unit 12, the third switch unit and the fourth switch unit 14 are maintained off.

[0141] Specifically, within the fifth preset time T5, when the first switch unit 11 and the switch module Q5 are turned off, the second switch unit 12 and the fourth switch unit 14 are turned on, the input current passes through the second switch unit 12, the fourth switch unit 14 and the inductor L, thereby storing energy (charging) the inductor L; and when the first switch unit 11 and the switch module Q5 are turned on, the second switch unit 12 and the fourth switch unit 14 are turned off, the input current passes through the inductor L, the first switch unit 11, the first capacitor C1 and the switch module Q5, the inductor L releases energy (discharges), and charges the first capacitor C1. And within a period of time after the fifth preset time T5, the first switch unit 11 and the switch module Q5 are controlled to be turned on, the second switch unit 12 and the fourth switch unit 14 are turned off, and the input current passes through the inductor L, the first switch unit 11, the first capacitor C1 and the switch module Q5 to charge the first capacitor C1; after this period of time, the first switch unit 11 is turned off, and the switch module Q5 is maintained on, and the second switch unit 12, the third switch unit and the fourth switch unit 14 are maintained off.

[0142] When the input voltage Us of the bridge circuit (i.e., the input voltage Us of the rectifier module 10) is in a negative half cycle, the fourth switch unit 14 is controlled to be turned off in the negative half cycle. When the input voltage Us crosses the zero point and then enters a preset time (specifically, the sixth preset time T6) in the negative half cycle, the first switch unit 11, the second switch unit 12, the third switch unit 13, and the switch module Q5 are subjected to the fifth switch control several times. Specifically, in the fifth switch control process, the switching states of the first switch unit 11 and the third switch unit 13 are the same. The second switch unit 12 and the switch module Q5 have the same switching state, while the first switch unit 11 and the second switch unit 12 have opposite switching states. That is, when the second switch unit 12 is on, the switch module Q5 is on, and the first switch unit 11 and the third switch unit 13 are off. When the second switch unit 12 is off, the switch module Q5 is off, and the first switch unit 11 and the third switch unit 13 are on. For a period of time after the sixth preset time T6, the second switch unit 12 and the switch module Q5 are controlled to be on, and the first switch unit 11 and the third switch unit 13 are controlled to be off. The number of times the fifth switch is controlled can be adjusted as needed.

[0143] Among them, the above-mentioned period of time after the sixth preset time T6 can be adjusted according to actual conditions, and the period of time includes but is not limited to the time from the sixth preset time T6 to the time when the current Is is zero (that is, when it is detected that no current passes through the diode in the second switch unit 12). After this period of time, the second switch unit 12 is turned off, and the switch module Q5 is maintained on, and the first switch unit 11, the third switch unit and the fourth switch unit 14 are maintained off.

[0144] Specifically, within the sixth preset time T6, when the first switch unit 11 and the third switch unit 13 are turned on, the second switch unit 12 and the switch module Q5 are turned off, the input current passes through the third switch unit 13, the first switch unit 11 and the inductor L, thereby storing energy (charging) the inductor L; when the first switch unit 11 and the third switch unit 13 are turned off, the second switch unit 12 and the switch module Q5 are turned on, the input current passes through the inductor L, the second switch unit 12, the second capacitor C2 and the switch module Q5, the inductor L releases energy (discharges), and charges the second capacitor C2. Within a period of time after the sixth preset time T6, the second switch unit 12 and the switch module Q5 are controlled to be turned on, the first switch unit 11 and the third switch unit 13 are turned off, and the input current passes through the inductor L, the second switch unit 12, the second capacitor C2 and the switch module Q5 to charge the second capacitor C2; after this period of time, the second switch unit 12 is turned off, and the switch module Q5 is maintained on, and the first switch unit 11, the third switch unit and the fourth switch unit 14 are maintained off.

[0145] Reference Figure 3 and Figure 8 , Figure 8 What is shown is a pulse diagram of the fourth control method for the rectifier module and the switch module in the embodiment of the present application, wherein the control method of the synchronous rectification method is the same and will not be repeated here.

[0146] When P2≤P<P3, the totem pole power factor correction circuit is controlled to switch to the multi-pulse mode. The specific control process is as follows:

[0147] When the input voltage Us of the bridge circuit (i.e., the input voltage Us of the rectifier module 10) is in a positive half-cycle, the second switch unit 12 and the fourth switch unit 14 are controlled to be off during the positive half-cycle. When the input voltage Us crosses zero and then enters a preset time (specifically, the seventh preset time T7) within the positive half-cycle, the first switch unit 11 is controlled to be on and the third switch unit 13 and the switch module Q5 are controlled to be in a third switching state several times. During the third switching control process, the switching states of the third switch unit 13 and the switch module Q5 are opposite, i.e., when the third switch unit 13 is on, the switch module Q5 is off, and when the third switch unit 13 is off, the switch module Q5 is on. For a period of time after the seventh preset time T7, the first switch unit is controlled to be on, the switch module Q5 is controlled to be on, and the third switch unit 13 is controlled to be off. The number of third switching controls can be adjusted as needed.

[0148] The aforementioned delay period after the input voltage Us crosses zero includes, but is not limited to, the time from when the input voltage Us crosses zero to when current flows through the diode in the first switch unit. Within a period after the seventh preset time T7, this period can be adjusted according to actual needs and includes, but is not limited to, the time from when the seventh preset time T7 to when the current Is reaches zero (i.e., when it is detected that no current flows through the diode in the first switch unit 11). After this period, the first switch unit 11 is turned off, the switch module Q5 is maintained on, and the second, third, and fourth switch units 12, 14 are maintained off.

[0149] Specifically, within the seventh preset time T7, when the third switch unit 13 is turned on and the switch module Q5 is turned off, the input current passes through the reactor L, the first switch unit 11, and the third switch unit 13, thereby storing (charging) the reactor L. When the third switch unit 13 is turned off, the switch module Q5 is turned on, and the input current passes through the reactor L, the first switch unit 11, the first capacitor C1, and the switch module Q5, causing the reactor L to release (discharge) energy and charge the first capacitor C1. Furthermore, within a period of time after the seventh preset time T7, the first switch unit 11 is controlled to be turned on, the switch module Q5 is controlled to be turned on, and the third switch unit 13 is controlled to be turned off, causing the input current to pass through the reactor L, the first switch unit 11, the first capacitor C1, and the switch module Q5, thereby charging the first capacitor C1. After this period of time, the first switch unit 11 is turned off, the switch module Q5 is maintained on, and the second switch unit 12, the third switch unit, and the fourth switch unit 14 are maintained off.

[0150] When the input voltage Us of the bridge circuit is in a negative half-cycle, the first switch unit 11 and the third switch unit 13 are controlled to be off during the negative half-cycle. When the input voltage Us crosses zero and then enters a preset time (specifically, an eighth preset time T8) within the negative half-cycle, the second switch unit 12 is controlled to be on and the fourth switch unit 14 and the switch module Q5 are subjected to a sixth switching control several times. During the sixth switching control process, the switching states of the fourth switch unit 14 and the switch module Q5 are opposite, that is, when the fourth switch unit 14 is on, the switch module Q5 is off, and when the fourth switch unit 14 is off, the switch module Q5 is on. For a period of time after the eighth preset time T8, the second switch unit 12 is controlled to be on, the switch module Q5 is controlled to be on, and the fourth switch unit 14 is controlled to be off. The number of sixth switching controls can be adjusted as needed.

[0151] The aforementioned delay period after the input voltage Us crosses zero includes, but is not limited to, the time from when the input voltage Us crosses zero to when current flows through the diode in the second switch unit. Within a period after the eighth preset time T8, this period can be adjusted according to actual needs and includes, but is not limited to, the time from when the eighth preset time T8 to when the current Is reaches zero (i.e., when it is detected that no current flows through the diode in the second switch unit 12). After this period, the second switch unit 12 is turned off, the switch module Q5 is maintained on, and the first switch unit 11, the third switch unit, and the fourth switch unit 14 are maintained off.

[0152] Specifically, within the eighth preset time T8, when the fourth switch unit 14 is turned on and the switch module Q5 is turned off, the input current passes through the reactor L, the second switch unit 12, and the fourth switch unit 14, thereby storing (charging) the reactor L. When the fourth switch unit 14 is turned off, the switch module Q5 is turned on, and the input current passes through the reactor L, the second switch unit 12, the second capacitor C2, and the switch module Q5, causing the reactor L to release (discharge) energy and charge the second capacitor C2. Furthermore, within a period of time after the eighth preset time T8, the second switch unit 12 and the switch module Q5 are controlled to be turned on and the fourth switch unit 14 is controlled to be turned off, causing the input current to pass through the reactor L, the second switch unit 12, the second capacitor C2, and the switch module Q5, thereby charging the second capacitor C2. After this period of time, the second switch unit 12 is turned off, the switch module Q5 is maintained turned on, and the first switch unit 11, the third switch unit, and the fourth switch unit 14 are maintained turned off.

[0153] It can be understood that in addition to the first to fourth control modes, the first control mode and the second control mode can be combined, or the third control mode and the fourth control mode can be combined to obtain other control modes. For example, the multi-pulse control mode in which the input voltage Us is in the positive half-cycle in the first control mode can be used in combination with the multi-pulse control mode in which the input voltage Us is in the negative half-cycle in the second control mode, and the multi-pulse control mode in which the input voltage Us is in the positive half-cycle in the third control mode can be used in combination with the multi-pulse control mode in which the input voltage Us is in the negative half-cycle in the fourth control mode, and so on, not limited to the above-mentioned combined control modes.

[0154] It can be understood that in the above four control methods, the conduction and shutdown of the corresponding elements are controlled within the positive half cycle, including but not limited to controlling the conduction and shutdown of the corresponding elements within a certain period of time within the positive half cycle (and this period of time can be adjusted according to actual needs), or in some other embodiments, the conduction and shutdown of the corresponding elements can be controlled within the entire positive half cycle; the conduction and shutdown of the corresponding elements are controlled in the same way within the negative half cycle.

[0155] Among them, the control of the rectifier module in all the above control methods specifically refers to the control of the bridge circuit, and the control of the switch unit refers to the control of the power tube. The preset time in the above control method can be reasonably adjusted according to demand, and the number of times the first switch unit 11, the second switch unit 12, the third switch unit 13, the fourth switch unit 14, or the switch module Q5 is turned on and off within the preset time can be reasonably adjusted according to demand. For example, the number of on and off times (i.e., the number of pulses) is N. When P2≤P<P3, if the current load parameter is a first value, when the first value increases to a second value, then N increases; if the current load parameter is a first value, when the first value decreases to a third value, then N decreases, thereby controlling the number of charging and discharging times of the reactor L. Optionally, the first value, the second value, and the third value are within the range of P2≤P<P3, the size of N is positively correlated with the load parameter to a certain extent, and the specific increase or decrease amount of N can be reasonably adjusted according to actual needs and is not specifically limited.

[0156] To more clearly describe the embodiment of the present invention, taking the load including an inverter module and a compressor as an example, and the load parameter being the load current as an example, the implementation process of the control method is as follows:

[0157] When it is detected that the bus voltage, i.e. the voltage required by the load, is greater than twice the peak value of the AC voltage, the totem pole power factor correction circuit enters the voltage doubling mode. That is, at this time the totem pole power factor correction circuit is as follows: Figure 1 The status shown, or Figure 3 The state of the switch module Q5 when it is closed is shown; the load current is detected; if the first threshold value P1 ≤ the load current < the second threshold value P2, the totem pole power factor correction circuit is controlled to be a synchronous rectification mode, which meets the requirements of the inverter module and the compressor, reduces the switching times and switching losses of the power tube, improves the circuit efficiency, and reduces the complexity of the control module 30, saving costs;

[0158] If the second threshold value P2 ≤ load current < third threshold value P3, the totem pole power factor correction circuit is controlled to switch to a multi-pulse mode, charging and discharging the reactor L several times and charging the first capacitor C1, or charging and discharging the reactor L several times and charging the second capacitor C2, which can meet the higher requirements of the inverter module and the compressor, as well as the harmonic requirements.

[0159] Reference Figure 9 , an embodiment of the present application further provides a device, including:

[0160] at least one processor 100;

[0161] at least one memory 200, for storing at least one program;

[0162] When at least one program is executed by at least one processor 100, at least one processor 100 implements the above control method.

[0163] The contents of the above-mentioned method embodiments are all applicable to the present device embodiment, and the functions specifically implemented by the present device embodiment are the same as those of the above-mentioned method embodiments.

[0164] An embodiment of the present invention further provides a device, including:

[0165] load;

[0166] The load is driven by the above-mentioned device.

[0167] Among them, the drive can include indirect drive and direct drive. For example, if the load is DC drive, it can be directly connected to the output end of the rectifier module 10 for direct drive; for example, if the load is AC drive, the load can include a primary load and a secondary load, and the primary load is connected to the secondary load, and the primary load is connected to the output end of the rectifier module 10. For example, the primary load can be an inverter module, and the secondary load can be a compressor. In other embodiments, it is not limited to this. The contents of the above-mentioned method embodiments are all applicable to the embodiments of this device, and the functions specifically implemented by the embodiments of this device are the same as those of the above-mentioned method embodiments.

[0168] An embodiment of the present invention further provides a storage medium storing a program that, when executed by a processor, implements the aforementioned control method. The contents of the aforementioned method embodiments are applicable to the present storage medium embodiment, and the functions implemented by the present storage medium embodiment are the same as those of the aforementioned method embodiments.

[0169] The embodiments of the present application are described in detail above in conjunction with the accompanying drawings, but the present application is not limited to the above embodiments. Various changes can be made within the scope of knowledge possessed by ordinary technicians in the technical field without departing from the purpose of the present application.

Claims

1. A control method, characterized in that: Applied to a totem pole power factor correction circuit, the totem pole power factor correction circuit comprising: A rectifier module, comprising an input end and an output end, wherein the input end is connected to an AC power source, and the output end is used to connect to a load; A reactor is provided between the rectifier module and the AC power supply; a capacitor module connected to the output end, the capacitor module including a first capacitor and a second capacitor, the first capacitor and the second capacitor are connected in series, and the capacitor module is connected in parallel to the output end; a switch module, one end of the switch module being connected to a first connection point between the first capacitor and the second capacitor, and the other end of the switch module being connected to the input end; Wherein, the rectifier module includes a bridge circuit, and the bridge circuit includes a first switch unit, a second switch unit, a third switch unit and a fourth switch unit; The first switch unit and the second switch unit are connected in series to form a first branch, the third switch unit and the fourth switch unit are connected in series to form a second branch, and the first branch and the second branch are connected in parallel to form the bridge circuit; A second connection point between the first switch unit and the third switch unit is connected to the first end of the first capacitor, a second end of the first capacitor is connected to the first end of the second capacitor, and a third connection point between the second switch unit and the fourth switch unit is connected to the second end of the second capacitor; A fourth connection point between the first switch unit and the second switch unit is connected to one end of the AC power supply, a fifth connection point between the third switch unit and the fourth switch unit is connected to the other end of the AC power supply, and the fifth connection point is connected to the second end of the first capacitor through the switch module; The reactor is provided between the fourth connection point and the AC power supply, or between the fifth connection point and the AC power supply; The control method comprises the following steps: When the voltage required by the load is greater than twice the peak value of the AC voltage, obtain the load parameters; Determining that the load parameter is greater than or equal to a first threshold and less than a second threshold, and controlling the totem pole power factor correction circuit to switch to a synchronous rectification mode; or determining that the load parameter is greater than or equal to a second threshold and less than a third threshold, controlling the totem pole power factor correction circuit to switch to a multi-pulse mode; The step of controlling the totem pole power factor correction circuit to switch to a multi-pulse mode comprises the following steps: determining that the input voltage of the bridge circuit is in a positive half cycle, and controlling the bridge circuit and the switch module to charge and discharge the reactor several times and charge the first capacitor during the positive half cycle; determining that the input voltage of the bridge circuit is in a negative half cycle, and controlling the bridge circuit and the switch module to charge and discharge the reactor several times and charge the second capacitor during the negative half cycle; The controlling the bridge circuit and the switch module to charge and discharge the reactor several times and charge the first capacitor comprises the following steps: Controlling the third switch unit to turn off, and performing a second switch control on the first switch unit, the second switch unit, the fourth switch unit, and the switch module several times within a preset time; controlling the first switch unit and the switch module to turn on, and controlling the second switch unit and the fourth switch unit to turn off within a period of time after the preset time; during the second switch control process, the second switch unit and the fourth switch unit have the same switch state, the first switch unit and the switch module have the same switch state, and the first switch unit and the second switch unit have opposite switch states; Alternatively, the second switch unit and the fourth switch unit are controlled to be turned off, the first switch unit is controlled to be turned on within a preset time, and the third switch control is performed on the third switch unit and the switch module several times; within a period of time after the preset time, the first switch unit is controlled to be turned on, the third switch unit is controlled to be turned off, and the switch module is controlled to be turned on; during the third switch control process, the switching states of the third switch unit and the switch module are opposite.

2. The control method according to claim 1, wherein: The controlling the totem pole power factor correction circuit to switch to a synchronous rectification mode comprises the following steps: Determining that the input voltage of the bridge circuit is in a first time period of a positive half cycle, controlling the first switch unit and the switch module to be turned on, and controlling the second switch unit, the third switch unit, and the fourth switch unit to be turned off; Determine that the input voltage of the bridge circuit is in a second time period of a negative half cycle, control the second switch unit and the switch module to be turned on, and control the first switch unit, the third switch unit, and the fourth switch unit to be turned off.

3. The control method according to claim 1, wherein: The rectifier module also includes a first power diode and a second power diode, the anode of the first power diode is connected to the second connection point, the cathode of the first power diode is connected to the first end of the first capacitor, the anode of the second power diode is connected to the second end of the second capacitor, and the cathode of the power diode is connected to the third connection point.

4. The control method according to claim 3, wherein: The controlling the bridge circuit and the switch module to charge and discharge the reactor several times and charge the first capacitor comprises the following steps: Controlling the first switch unit and the switch module to be turned on, controlling the second switch unit and the fourth switch unit to be turned off, and controlling the third switch unit to be turned on and off several times within a preset time; Or control the third switch unit to turn off and control the switch module to turn on, and perform the first switch control on the first switch unit, the second switch unit and the fourth switch unit several times within a preset time; control the first switch unit to turn on and control the second switch unit and the fourth switch unit to turn off after the preset time; during the first switch control process, the switching states of the second switch unit and the fourth switch unit are the same, and the switching state of the second switch unit is opposite to that of the first switch unit.

5. The control method according to claim 3, wherein: The controlling the bridge circuit and the switch module to charge and discharge the reactor several times and charge the second capacitor comprises the following steps: Controlling the second switch unit and the switch module to be turned on, controlling the first switch unit and the third switch unit to be turned off, and controlling the fourth switch unit to be turned on and off several times within a preset time; Or the fourth switch unit is controlled to be turned off and the switch module is controlled to be turned on, and the fourth switch control is performed on the first switch unit, the second switch unit and the third switch unit several times within a preset time; after the preset time, the first switch unit and the third switch unit are controlled to be turned off, and the second switch unit is controlled to be turned on; during the fourth switch control process, the switching states of the first switch unit and the third switch unit are the same, and the switching states of the first switch unit and the second switch unit are opposite.

6. The control method according to claim 1, wherein: The controlling the bridge circuit and the switch module to charge and discharge the reactor several times and charge the second capacitor comprises the following steps: Controlling the fourth switch unit to turn off, and performing a fifth switch control on the first switch unit, the third switch unit, the second switch unit, and the switch module several times within a preset time; controlling the second switch unit and the switch module to turn on, and controlling the first switch unit and the third switch unit to turn off within a period of time after the preset time; during the fifth switch control process, the first switch unit and the third switch unit have the same switch state, the second switch unit and the switch module have the same switch state, and the first switch unit and the second switch unit have opposite switch states; Alternatively, the first switch unit and the third switch unit are controlled to be turned off, the second switch unit is controlled to be turned on within a preset time, and the sixth switch control is performed on the fourth switch unit and the switch module several times; within a period of time after the preset time, the second switch unit is controlled to be turned on, the fourth switch unit is controlled to be turned off, and the switch module is controlled to be turned on; during the sixth switch control process, the switching states of the fourth switch unit and the switch module are opposite.

7. The control method according to claim 1, wherein: The switch module includes a relay or a switch tube unit; The switch tube unit includes a fifth diode, a sixth diode, a seventh diode, an eighth diode and a first switch tube, the fifth diode and the sixth diode are connected in series to form a first diode branch, the seventh diode and the eighth diode are connected in series to form a second diode branch, the first switch tube, the first diode branch and the second diode branch are connected in parallel, the connection point between the fifth diode and the sixth diode is led out as one end of the switch module, and the connection point between the seventh diode and the eighth diode is led out as the other end of the switch module; Or the switch tube unit includes a second switch tube and a third switch tube connected in reverse parallel; Alternatively, the switch tube unit includes a fourth switch tube and a fifth switch tube connected in reverse series, and both the fourth switch tube and the fifth switch tube are anti-parallel connected with a diode.

8. The control method according to claim 1, wherein: The following steps are also included: The number of times the reactor is charged and discharged is controlled according to the load parameter.

9. The control method according to any one of claims 1 to 8, characterized in that: The load parameter includes at least one of load current, load power, load operating pressure and load frequency.

10. A device, characterized in that: include: at least one processor; at least one memory for storing at least one program; When the at least one program is executed by the at least one processor, the at least one processor implements the control method according to any one of claims 1 to 9.

11. A device, characterized in that include: load; The load is driven by the device according to claim 10.

Images