An uninterrupted PFC circuit and air conditioner

Abstract

The application discloses an uninterrupted PFC circuit and an air conditioner, the uninterrupted PFC circuit comprises a power supply rectification module and at least one PFC circuit module connected with the power supply rectification module, each PFC circuit module comprises a first controllable switch tube and a second controllable switch tube for adjusting the working state of the PFC circuit module; the PFC circuit module at least comprises a first working state working when the first controllable switch tube is in an off state, a second working state working when the first controllable switch tube and the second controllable switch tube are both in the off state, and a third working state working when the second controllable switch tube is in the off state. Compared with the prior art, the application can maintain the normal working of the PFC circuit module when the first controllable switch tube and the second controllable switch tube appear short circuit or open circuit faults, avoid the problem that the controllable switch tube is damaged due to excessive stress of the PFC circuit module, and influence the air conditioner operation.

Description

Technical Field

[0001] This invention relates to the field of air conditioning, and in particular to an uninterrupted PFC circuit and an air conditioner. Background Technology

[0002] The current single-phase air conditioner outdoor unit drive solution uses power filtering and multi-channel BOOST power factor correction to provide 380V bus voltage to power the compressor IPM module and fan IPM module.

[0003] In practical applications of multi-channel BOOST circuits, abnormalities can lead to overheating of IGBTs and diodes. High turn-on and turn-off losses will cause the multi-channel BOOST circuit to bear significant voltage stress, which can easily damage the controllable switching transistors in the multi-channel BOOST circuit, such as IGBTs, causing the air conditioner to stop working. Some air conditioner outdoor units operate in relatively harsh environments, especially in the Middle East, where the environment is extremely harsh. When an air conditioner breaks down, after-sales service is quite difficult.

[0004] Therefore, how to design an uninterrupted PFC circuit and air conditioner that can continue to operate even when the controllable switching transistor is damaged, thereby reducing after-sales work, is a technical problem that the industry urgently needs to solve. Summary of the Invention

[0005] In view of the problem that in the existing technology, the controllable switching tube in the driving scheme of the outdoor unit of the air conditioner is subjected to large stress and is prone to damage, thus affecting the operation of the air conditioner, the present invention proposes an uninterrupted PFC circuit and an air conditioner.

[0006] The technical solution of the present invention is to propose an uninterrupted PFC circuit, including a power rectifier module and at least one PFC circuit module connected to the power rectifier module. Each PFC circuit module includes a first controllable switch and a second controllable switch, which are used to adjust the working state of the PFC circuit module.

[0007] The PFC circuit module includes at least a first operating state when the first controllable switch is in the off state, a second operating state when both the first controllable switch and the second controllable switch are in the off state, and a third operating state when the second controllable switch is in the off state.

[0008] Based on the above scheme, the present invention configures the PFC circuit with three working states, which can automatically operate in the first working state when the first controllable switch is damaged; automatically operate in the second working state when both the first and second controllable switches are damaged; and operate in the third working state when the second controllable switch is damaged.

[0009] Based on this, regardless of whether either the first or second controllable switch is damaged, or even if they are damaged simultaneously, the PFC circuit can automatically switch to a suitable operating state to maintain the operation of the air conditioner. This achieves uninterrupted operation of the PFC circuit and avoids the problem of damage to the controllable switch due to excessive stress, which would affect the operation of the air conditioner.

[0010] Furthermore, each of the PFC circuit modules in this invention includes a first PFC circuit, a second PFC circuit, and a third PFC circuit;

[0011] When the first PFC circuit is working, the PFC circuit module is in the first working state;

[0012] When the second PFC circuit is working, the PFC circuit module is in the second working state;

[0013] When the third PFC circuit is working, the PFC circuit module is in the third working state.

[0014] Based on the above scheme, this invention divides each PFC circuit module into three PFC circuits, associates the state of the controllable switch with the conduction of the three PFC circuits, and corresponds the operation of the three PFC circuits with the three working states of the PFC circuit module. This enables automatic switching of the first PFC circuit, the second PFC circuit, and the third PFC circuit when the controllable switch fails, ensuring uninterrupted operation of the PFC circuit module.

[0015] Furthermore, the PFC circuit module described in this invention includes a first PFC circuit module for powering the compressor IPM module. In the first PFC circuit module, the first PFC circuit includes inductor L1, inductor L2, capacitor C1, capacitor C2, diode D1, and switching transistor G2.

[0016] One end of the inductor L1 is connected to the first end of the power rectifier module, the other end of the inductor L1 is connected to one end of the switching transistor G2, the other end of the switching transistor G2 is connected to one end of the capacitor C2, and the other end of the capacitor C2 is connected to the second end of the power rectifier module.

[0017] One end of capacitor C1 is connected between inductor L1 and switching transistor G2, and the other end of capacitor C1 is connected to one end of inductor L2. The other end of inductor L2 is connected to the second end of the power rectifier module.

[0018] The positive terminal of diode D1 is connected between capacitor C1 and inductor L2, and the negative terminal of diode D1 is connected between switch G2 and capacitor C2.

[0019] The compressor IPM module is connected in parallel across the capacitor C2, and the switching transistor G2 is used as the second controllable switching transistor.

[0020] Based on the above scheme, the present invention provides a specific configuration of the first PFC circuit in the first PFC circuit module for powering the compressor IPM module. The first PFC circuit can adapt to operation under low power conditions and realize step-down and step-up control to meet the usage requirements of the compressor under low power conditions.

[0021] Furthermore, in this invention, the second PFC circuit in the first PFC circuit module includes inductor L1, inductor L2, capacitor C1, capacitor C2, and diode D1.

[0022] One end of the inductor L1 is connected to the first end of the power rectifier module, the other end of the inductor L1 is connected to one end of the capacitor C1, the other end of the capacitor C1 is connected to one end of the inductor L2, and the other end of the inductor L2 is connected to the second end of the power rectifier module.

[0023] The positive terminal of diode D1 is connected between capacitor C1 and inductor L2, the negative terminal of diode D1 is connected to one end of capacitor C2, and the other end of capacitor C2 is connected to the second terminal of the power rectifier module.

[0024] The compressor IPM module is connected in parallel across the capacitor C2.

[0025] Based on the above scheme, the present invention provides a specific configuration of the second PFC circuit in the first PFC circuit module for powering the compressor IPM module. The second PFC circuit can adapt to operation under low power conditions and realize step-down and step-up control to meet the usage requirements of the compressor under low power conditions.

[0026] Furthermore, in the first PFC circuit module of the present invention, the third PFC circuit includes inductor L1, inductor L2, capacitor C1, capacitor C2, diode D1, and switching transistor G1.

[0027] One end of the inductor L1 is connected to the first end of the power rectifier module, the other end of the inductor L1 is connected to one end of the switching transistor G1, and the other end of the switching transistor G1 is connected to the second end of the power rectifier module.

[0028] One end of capacitor C1 is connected between inductor L1 and switching transistor G1, and the other end of capacitor C1 is connected to one end of inductor L2. The other end of inductor L2 is connected to the second terminal of the power rectifier module. The positive terminal of diode D1 is connected between capacitor C1 and inductor L2, and the negative terminal of diode D1 is connected to one end of capacitor C2. The other end of capacitor C2 is connected between inductor L2 and the second terminal of the power rectifier module.

[0029] The compressor IPM module is connected in parallel across the capacitor C2, and the switching transistor G1 is used as the first controllable switching transistor.

[0030] Based on the above scheme, the present invention provides a specific configuration of the third PFC circuit in the first PFC circuit module for powering the compressor IPM module. The third PFC circuit can adapt to operation under high power conditions and realize step-down and step-up control to meet the usage requirements of the compressor under high power conditions.

[0031] Furthermore, in this invention, when the switching transistors G1 and G2 are in normal operation, the first PFC circuit module is configured to control the first PFC circuit or the second PFC circuit to operate when the compressor speed is lower than the first threshold speed.

[0032] When the compressor speed is higher than the first threshold speed, the third PFC circuit is controlled to work.

[0033] Based on the above solution, this invention can actively control the conduction state of switching transistors G1 and G2 in combination with the compressor speed when neither of them is damaged, thereby switching the operation of the first PFC circuit, the second PFC circuit, and the third PFC circuit, and adapting to the control requirements of the compressor at different speeds.

[0034] Furthermore, the PFC circuit module described in this invention also includes a second PFC circuit module for powering the wind turbine IPM module. In the second PFC circuit module, the first PFC circuit includes inductor L3, inductor L4, capacitor C3, capacitor C4, diode D2, and switching transistor G4.

[0035] One end of the inductor L3 is connected to the first end of the power rectifier module, the other end of the inductor L3 is connected to one end of the switching transistor G4, the other end of the switching transistor G4 is connected to one end of the capacitor C3, and the other end of the capacitor C3 is connected to the second end of the power rectifier module.

[0036] One end of capacitor C4 is connected between inductor L3 and switching transistor G4, and the other end of capacitor C4 is connected to one end of inductor L4. The other end of inductor L4 is connected to the second end of the power rectifier module.

[0037] The positive terminal of diode D2 is connected between capacitor C4 and inductor L4, and the negative terminal of diode D2 is connected between switch G4 and capacitor C3;

[0038] The wind turbine IPM module is connected in parallel across the capacitor C3, and the switching transistor G4 is used as the second controllable switching transistor.

[0039] Based on the above scheme, the present invention provides a specific configuration of the first PFC circuit in the second PFC circuit module used to power the wind turbine IPM module. The first PFC circuit can adapt to operation under low power conditions and realize step-down and step-up control to meet the usage requirements of the wind turbine under low power conditions.

[0040] Furthermore, in the second PFC circuit module of the present invention, the second PFC circuit includes inductor L3, inductor L4, capacitor C3, capacitor C4, and diode D2;

[0041] One end of the inductor L3 is connected to the first end of the power rectifier module, the other end of the inductor L3 is connected to one end of the capacitor C4, the other end of the capacitor C4 is connected to one end of the inductor L4, and the other end of the inductor L4 is connected to the second end of the power rectifier module.

[0042] The positive terminal of diode D2 is connected between capacitor C4 and inductor L4, the negative terminal of diode D2 is connected to one end of capacitor C3, and the other end of capacitor C3 is connected to the second terminal of the power rectifier module.

[0043] The wind turbine IPM module is connected in parallel across the capacitor C3.

[0044] Based on the above scheme, the present invention provides a specific configuration of the second PFC circuit in the second PFC circuit module for powering the wind turbine IPM module. The second PFC circuit can adapt to operation under low power conditions and realize step-down and step-up control to meet the usage requirements of the wind turbine under low power conditions.

[0045] Furthermore, in this invention, the third PFC circuit in the second PFC circuit module includes inductor L3, inductor L4, capacitor C3, capacitor C4, diode D2, and switching transistor G3.

[0046] One end of the inductor L3 is connected to the first end of the power rectifier module, the other end of the inductor L3 is connected to one end of the switching transistor G3, and the other end of the switching transistor G2 is connected to the second end of the power rectifier module.

[0047] One end of capacitor C4 is connected between inductor L3 and switching transistor G3, and the other end of capacitor C4 is connected to one end of inductor L4. The other end of inductor L4 is connected to the second terminal of the power rectifier module. The anode of diode D2 is connected between capacitor C4 and inductor L4, and the cathode of diode D2 is connected to one end of capacitor C3. The other end of capacitor C3 is connected between inductor L4 and the second terminal of the power rectifier module.

[0048] The wind turbine IPM module is connected in parallel across the capacitor C3, and the switching transistor G3 is used as the first controllable switching transistor.

[0049] Based on the above scheme, the present invention provides a specific configuration of the third PFC circuit in the second PFC circuit module used to power the wind turbine IPM module. The third PFC circuit can adapt to operation under high power conditions and realize step-down and step-up control to meet the usage requirements of the wind turbine under high power conditions.

[0050] Furthermore, in this invention, when the switching transistors G3 and G4 are in normal operation, the second PFC circuit module is configured to control the first PFC circuit or the second PFC circuit to operate when the fan speed is lower than the second threshold speed.

[0051] When the fan speed is higher than the second threshold speed, the third PFC circuit is controlled to work.

[0052] Based on the above solution, this invention can actively control the conduction state of switching transistors G3 and G4 in combination with the fan speed when neither of them is damaged, thereby switching the operation of the first PFC circuit, the second PFC circuit, and the third PFC circuit, which can adapt to the control requirements of the fan at different speeds.

[0053] Furthermore, in this invention, the first controllable switch and the second controllable switch are IGBTs or MOSFETs.

[0054] Based on the above solution, this invention can avoid the problem of IGBT or MOSFET being damaged due to excessive stress, thereby affecting the operation of the air conditioner.

[0055] The present invention also proposes an air conditioner having the above-mentioned uninterrupted PFC circuit.

[0056] Compared with the prior art, the present invention has at least the following beneficial effects:

[0057] This invention divides the PFC circuit module into a first PFC circuit, a second PFC circuit, and a third PFC circuit, which are activated corresponding to the on states of the first and second controllable switches. This enables automatic switching of the first PFC circuit when the first controllable switch fails, automatic switching of the second PFC circuit when both the first and second controllable switches fail, and automatic switching of the third PFC circuit when the second controllable switch fails. This ensures the normal operation of the PFC circuit module regardless of which controllable switch fails, or even both controllable switches fail simultaneously, guaranteeing continuous operation and preventing damage to the controllable switches due to excessive stress, which could affect air conditioning operation. Attached Figure Description

[0058] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0059] Figure 1 This is a circuit topology diagram of the first PFC circuit module in this invention;

[0060] Figure 2 This is a circuit topology diagram of the first PFC circuit in the first PFC circuit module of the present invention;

[0061] Figure 3 This is a circuit topology diagram of the second PFC circuit in the first PFC circuit module of the present invention;

[0062] Figure 4 This is a circuit topology diagram of the third PFC circuit in the first PFC circuit module of the present invention;

[0063] Figure 5 This is a schematic diagram of the working process of the first PFC circuit module in this invention;

[0064] Figure 6 This is a circuit topology diagram of the second PFC circuit module in this invention;

[0065] Figure 7 This is a circuit topology diagram of the first PFC circuit in the second PFC circuit module of the present invention;

[0066] Figure 8 This is a circuit topology diagram of the second PFC circuit in the second PFC circuit module of the present invention;

[0067] Figure 9This is a circuit topology diagram of the third PFC circuit in the second PFC circuit module of the present invention;

[0068] Figure 10 This is a schematic diagram of the working process of the second PFC circuit module in this invention;

[0069] Figure 11 This is a circuit diagram of the uninterrupted PFC circuit in this invention;

[0070] Figure 12 This is a schematic diagram of the circuit topology of the uninterrupted PFC circuit in this invention. Detailed Implementation

[0071] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0072] Therefore, a feature pointed out in this specification is used to describe one feature of one embodiment of the invention, and does not imply that every embodiment of the invention must have the described feature. Furthermore, it should be noted that this specification describes many features. Although certain features may be combined to illustrate possible system designs, these features may also be used in other combinations not explicitly stated. Therefore, unless otherwise stated, the described combinations are not intended to be limiting.

[0073] The principles and structure of the present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0074] In practical applications of multi-channel BOOST circuits, abnormalities can lead to overheating of IGBTs and diodes. High turn-on and turn-off losses will cause the multi-channel BOOST circuit to be subjected to significant voltage stress, which can easily damage the controllable switching transistors in the multi-channel BOOST circuit, such as IGBTs, thereby causing the air conditioner to stop working.

[0075] To address the aforementioned problems, this invention proposes an uninterrupted PFC circuit, designed to maintain circuit operation even when the controllable switching transistor fails, thereby preventing disruption to air conditioner operation. Please see the appendix. Figure 11 The uninterrupted PFC circuit proposed in this invention includes a power rectifier module and at least one PFC circuit module connected to the power rectifier module. Each PFC circuit module is connected to an IPM module to provide power input.

[0076] Here, the power rectifier module is connected to the power supply to obtain AC power and to rectify the AC power to output DC power, which serves as the power input for the PFC circuit module.

[0077] PFC circuit modules can operate in either boost or buck mode. When operating in boost mode, they function as BOOST circuits, and when operating in buck mode, they function as BUCK circuits. In the air conditioning industry, PFC circuit modules are generally used as BOOST circuits, which is the application of multi-channel BOOST circuits mentioned earlier.

[0078] In air conditioners, the loads that generally need to be controlled are the compressor and the fan. The IPM module (intelligent power module) is the circuit structure that controls the operation of the compressor and the fan. The IPM used to control the compressor is called the compressor IPM module, and the IPM used to control the fan is called the fan IPM module. Both the compressor IPM module and the fan IPM module need to be powered by a PFC circuit module to boost or buck the voltage. In the solution provided by this invention, the compressor IPM module and the fan IPM module are integrated together and the power input is provided by the same power rectifier module. In other embodiments of this invention, the compressor IPM module and the fan IPM module can also be designed separately by setting two power rectifier modules to provide power input for the compressor IPM module and the fan IPM module respectively.

[0079] Furthermore, the uninterrupted PFC circuit provided by this invention can also be applied to other fields, requiring only the adjustment of the corresponding IPM module.

[0080] In this invention, each PFC circuit module has a first controllable switch and a second controllable switch for adjusting the operating state of the PFC circuit module. Theoretically, the output of the PFC circuit module can be adjusted by regulating the conduction state and conduction frequency of the first and second controllable switches. As mentioned above, the first and second controllable switches may be subject to significant stress, which could lead to their damage. To solve this problem, the PFC circuit module provided by this invention includes at least a first operating state when the first controllable switch is in the off state, a second operating state when both the first and second controllable switches are in the off state, and a third operating state when the second controllable switch is in the off state.

[0081] Under this design, if the first controllable switch fails, it is equivalent to the first controllable switch being in an open state, at which point the PFC circuit module can operate in the first operating state. If both the first and second controllable switches fail, it is equivalent to both being in an open state, at which point the PFC circuit module can operate in the second operating state. If the second controllable switch fails, it is equivalent to the second controllable switch being in an open state, at which point the PFC circuit module can operate in the third operating state. In other words, regardless of whether either the first or second controllable switch fails, or even if both fail simultaneously, the PFC circuit module can continue to operate, achieving uninterrupted operation and preventing the air conditioner from shutting down.

[0082] Specifically, each PFC circuit module provided by the present invention includes a first PFC circuit, a second PFC circuit, and a third PFC circuit;

[0083] When the first PFC circuit is working, the PFC circuit module is in the first working state;

[0084] When the second PFC circuit is working, the PFC circuit module is in the second working state;

[0085] When the third PFC circuit is working, the PFC circuit is in the third working state;

[0086] As mentioned above, when the first controllable switch is in the off state, the PFC circuit module is in the first working state. That is, in this invention, the first PFC circuit is associated with the first controllable switch, so that when the first controllable switch is in the off state, the PFC circuit module can be switched to the form of the first PFC circuit. Here, the first PFC circuit is actually the new circuit form exhibited by the PFC circuit module in this invention when the first controllable switch is in the off state. It does not require active switching. When the first controllable switch is off, the PFC circuit module will automatically convert to the form of the first PFC circuit, so that the PFC circuit module works in the form of the first PFC circuit, ensuring the continuous operation of the PFC circuit module.

[0087] Similarly, when both the first and second controllable switches are in the off state, the PFC circuit module can automatically switch to the form of the second PFC circuit, thereby allowing the PFC circuit module to work in the second PFC circuit and ensuring the continuous operation of the PFC circuit module.

[0088] When both controllable switches are in the off state, the PFC circuit module can automatically switch to the form of the third PFC circuit, so that the PFC circuit module can work in the third PFC circuit and ensure the continuous operation of the PFC circuit module.

[0089] In this scheme, based on the PFC circuit module, the present invention associates the states of the first and second controllable switches with the conduction of the three PFC circuits, and corresponds the operation of the three PFC circuits with the three working states of the PFC circuit module. This enables automatic switching of the first, second, and third PFC circuits when the controllable switches fail, ensuring uninterrupted operation of the PFC circuit module.

[0090] Please see the appendix Figure 1 This is the circuit topology of the first PFC circuit module used to power the compressor IPM module in this invention. Under this circuit topology, the first PFC circuit module includes inductor L1, inductor L2, capacitor C1, capacitor C2, diode D1, switch G1, and switch G2.

[0091] Here, switch G1 is used as the first controllable switch, and switch G2 is used as the second controllable switch;

[0092] One end of inductor L1 is connected to the first end of the power rectifier module, the other end of inductor L1 is connected to one end of switching transistor G2, the other end of switching transistor G2 is connected to one end of capacitor C2, and the other end of capacitor C2 is connected to the second end of the power rectifier module.

[0093] One end of the switching transistor G1 is connected between the inductor L1 and the switching transistor G2, and the other end of the switching transistor G1 is connected to the second end of the power rectifier module.

[0094] One end of capacitor C1 is connected between inductor L1 and switching transistor G2, and the other end of capacitor C1 is connected to one end of inductor L2. The other end of inductor L2 is connected to the second end of the power rectifier module.

[0095] The positive terminal of diode D1 is connected between capacitor C1 and inductor L2, and the negative terminal of diode D1 is connected between switching transistor G2 and capacitor C2.

[0096] The above topology is also the topology of the first PFC circuit module in this invention. By controlling the conduction state of switching transistors G1 and G2, the boost / buck control of the compressor IPM module in low power state and boost / buck control in high power state can be realized.

[0097] The aforementioned first PFC circuit module can be divided into a first PFC circuit, a second PFC circuit, and a third PFC circuit. These three PFC circuits switch according to the conduction states of switching transistors G1 and G2. Please refer to the appendix. Figure 2 In the first PFC circuit module of the present invention, the first PFC circuit includes inductor L1, inductor L2, capacitor C1, capacitor C2, diode D1, and switching transistor G2.

[0098] One end of inductor L1 is connected to the first end of the power rectifier module, the other end of inductor L1 is connected to one end of switching transistor G2, the other end of switching transistor G2 is connected to one end of capacitor C2, and the other end of capacitor C2 is connected to the second end of the power rectifier module.

[0099] One end of capacitor C1 is connected between inductor L1 and switching transistor G2, and the other end of capacitor C1 is connected to one end of inductor L2. The other end of inductor L2 is connected to the second end of the power rectifier module.

[0100] The positive terminal of diode D1 is connected between capacitor C1 and inductor L2, and the negative terminal of diode D1 is connected between switching transistor G2 and capacitor C2.

[0101] The compressor IPM module is connected in parallel across capacitor C2, and the switching transistor G2 is used as a second controllable switching transistor.

[0102] The working principle of this first PFC circuit is as follows: After rectification, the power supply flows from the first terminal of the power rectifier module (i.e., the attached terminal). Figure 2 Starting from the upper part of the power rectifier module, the circuit passes through inductor L1, switching transistor G2, and capacitor C2 in sequence before returning to the second end of the power rectifier module. During this process, capacitor C2 stores energy and provides energy to the compressor IPM module (i.e., the load). The output voltage polarity is positive at the top and negative at the bottom.

[0103] At the same time, capacitor C1 forms a loop current through switching transistor G2, capacitor C2, and inductor L2, which superimposes voltage on capacitor C2, thus boosting the voltage. It also provides current to inductor L2. At this time, capacitor C1 is powered, with the polarity being positive at the top and negative at the bottom, and diode D1 is in the off state.

[0104] As can be seen from the above-mentioned working process of the first PFC circuit, in the event of a failure of the switching transistor G1, the first PFC circuit can work independently and perform the corresponding boost action to maintain the power supply to the compressor IPM module, thus preventing the air conditioner from shutting down. The first PFC circuit can adapt to working under low power conditions and realize voltage reduction and boost control to meet the usage requirements of the compressor under low power conditions.

[0105] Please see the appendix Figure 3 In the first PFC circuit module of the present invention, the second PFC circuit includes inductor L1, inductor L2, capacitor C1, capacitor C2, and diode D1;

[0106] One end of inductor L1 is connected to the first terminal of the power rectifier module, the other end of inductor L1 is connected to one end of capacitor C1, the other end of capacitor C1 is connected to one end of inductor L2, and the other end of inductor L2 is connected to the second terminal of the power rectifier module.

[0107] The positive terminal of diode D1 is connected between capacitor C1 and inductor L2, the negative terminal of diode D1 is connected to one end of capacitor C2, and the other end of capacitor C2 is connected to the second terminal of the power rectifier module.

[0108] The compressor IPM module is connected in parallel across capacitor C2.

[0109] The working principle of the second PFC circuit is as follows: After the power supply is rectified, it starts from the first end of the power rectifier module, passes through inductor L1, capacitor C1, diode D1, and capacitor C2 in sequence, and returns to the second end of the power rectifier module. During this process, capacitor C2 stores energy and provides energy to the compressor IPM module. The polarity of the output voltage is positive at the top and negative at the bottom.

[0110] At the same time, inductor L2 provides energy, which passes through diode D1 and capacitor C2 in sequence and returns to inductor L2 to form a loop current. This current is superimposed on the voltage of capacitor C2, which plays a boosting role. The output voltage of inductor L2 is positive at the top and negative at the bottom.

[0111] As can be seen from the above-described working process of the second PFC circuit, in the event of damage to switching transistors G1 and G2, the second PFC circuit can work independently and perform corresponding boosting actions to maintain power supply to the compressor IPM module, thus preventing the air conditioner from shutting down. This second PFC circuit can adapt to operation under low power conditions and achieve voltage reduction and boosting control to meet the compressor's usage requirements under low power conditions.

[0112] Please see the appendix Figure 4 In the first PFC circuit module of the present invention, the third PFC circuit includes inductor L1, inductor L2, capacitor C1, capacitor C2, diode D1, and switching transistor G1.

[0113] One end of inductor L1 is connected to the first end of the power rectifier module, and the other end of inductor L1 is connected to one end of switching transistor G1. The other end of switching transistor G1 is connected to the second end of the power rectifier module.

[0114] One end of capacitor C1 is connected between inductor L1 and switching transistor G1, and the other end of capacitor C1 is connected to one end of inductor L2. The other end of inductor L2 is connected to the second terminal of the power rectifier module. The positive terminal of diode D1 is connected between capacitor C1 and inductor L2, and the negative terminal of diode D1 is connected to one end of capacitor C2. The other end of capacitor C2 is connected between inductor L2 and the second terminal of the power rectifier module.

[0115] The compressor IPM module is connected in parallel across capacitor C2, and the switching transistor G1 is used as the first controllable switching transistor.

[0116] Under this third PFC circuit, its working principle is as follows: After the power supply is rectified, it starts from the first end of the power rectifier module, passes through inductor L1 and switching transistor G1 in sequence to form a power supply loop, charging inductor L1 and increasing the current. At the same time, inductor L2 passes through diode D1 and capacitor C2 to form a current loop, charging capacitor C2. At the same time, capacitor C2 provides energy to the compressor IPM module. The polarity of the output voltage is positive at the top and negative at the bottom.

[0117] As can be seen from the working process of the third PFC circuit, in the event of a failure of the switching transistor G2, the third PFC circuit can work independently and perform the corresponding boost action to maintain the power supply to the compressor IPM module, thus preventing the air conditioner from shutting down. This third PFC circuit can adapt to high-power operation and realize voltage reduction and boost control to meet the compressor's usage requirements under high-power conditions.

[0118] As can be seen from the above description of the first PFC circuit, the second PFC circuit, and the third PFC circuit, when either the first or the second controllable switch is damaged, or when both the first and the second controllable switch are damaged, the present invention can maintain the continuous operation of the PFC circuit module by conducting the corresponding PFC circuit, thereby achieving uninterrupted operation and avoiding the problem of air conditioner shutdown.

[0119] The above situations describe the abnormal damage to the first and second controllable switching transistors. When the first and second controllable switching transistors are normal, the present invention can also provide different outputs to the compressor IPM module by actively controlling the conduction state of the first and second controllable switching transistors.

[0120] Please see the appendix Figure 5 In this invention, when switching transistors G1 and G2 are in normal state, the control flow of the first PFC circuit module is as follows: when the compressor speed is lower than the first threshold speed, control the first PFC circuit or the second PFC circuit to work.

[0121] When the compressor speed is higher than the first threshold speed, the third PFC circuit is controlled to work.

[0122] As mentioned above, the first PFC circuit and the second PFC circuit are generally suitable for control under low power conditions. This invention can determine whether the compressor needs to be controlled under low power conditions or high power conditions by judging the first threshold speed. If the speed is lower than the first threshold speed, it is determined that the compressor is suitable for control under low power conditions. Then, by actively controlling the switch G1 to turn off, or by simultaneously controlling the switch G1 and the switch G2 to turn off, the first PFC circuit module can work in the first PFC circuit or the second PFC circuit, which can meet the control requirements of the compressor at the current speed.

[0123] Similarly, if the compressor speed is higher than the first threshold speed, it is determined that the compressor is suitable for high-power control at this time. Then, by actively controlling the switch G2 to turn off, the first PFC circuit module is made to work in the third PFC circuit, which can meet the control requirements of the compressor at the current speed.

[0124] The first threshold speed is set to 60% of the compressor's maximum speed.

[0125] Based on the above solution, this invention can actively control the conduction state of switching transistors G1 and G2 in combination with the compressor speed when neither of them is damaged, thereby switching the operation of the first PFC circuit, the second PFC circuit, and the third PFC circuit, and adapting to the control requirements of the compressor at different speeds.

[0126] Please see the appendix Figure 6 This is the circuit topology of the second PFC circuit module used to power the wind turbine IPM module in this invention. Under this circuit topology, the second PFC circuit module includes inductor L3, inductor L4, capacitor C3, capacitor C4, diode D2, switch G3, and switch G4.

[0127] Here, switch G3 is used as the first controllable switch, and switch G4 is used as the second controllable switch;

[0128] One end of inductor L3 is connected to the first end of the power rectifier module, the other end of inductor L3 is connected to one end of switching transistor G4, the other end of switching transistor G4 is connected to one end of capacitor C3, and the other end of capacitor C3 is connected to the second end of the power rectifier module.

[0129] One end of the switching transistor G3 is connected between the inductor L3 and the switching transistor G4, and the other end of the switching transistor G3 is connected to the second end of the power rectifier module.

[0130] One end of capacitor C4 is connected between inductor L3 and switching transistor G4, and the other end of capacitor C4 is connected to one end of inductor L4. The other end of inductor L4 is connected to the second end of the power rectifier module.

[0131] The positive terminal of diode D2 is connected between capacitor C4 and inductor L4, and the negative terminal of diode D2 is connected between switching transistor G4 and capacitor C3.

[0132] The above topology is also the topology of the second PFC circuit module in this invention. By controlling the conduction state of switching transistors G3 and G4, the boost / buck control of the compressor IPM module in low power state and boost / buck control in high power state can be realized.

[0133] The aforementioned second PFC circuit module can be divided into a first PFC circuit, a second PFC circuit, and a third PFC circuit. These three PFC circuits switch according to the conduction states of switching transistors G3 and G4. Please refer to the appendix. Figure 7 In the second PFC circuit module of the present invention, the first PFC circuit includes inductor L3, inductor L4, capacitor C3, capacitor C4, diode D2, and switching transistor G4.

[0134] One end of inductor L3 is connected to the first end of the power rectifier module, the other end of inductor L3 is connected to one end of switching transistor G4, the other end of switching transistor G4 is connected to one end of capacitor C3, and the other end of capacitor C3 is connected to the second end of the power rectifier module.

[0135] One end of capacitor C4 is connected between inductor L3 and switching transistor G4, and the other end of capacitor C4 is connected to one end of inductor L4. The other end of inductor L4 is connected to the second end of the power rectifier module.

[0136] The positive terminal of diode D2 is connected between capacitor C4 and inductor L4, and the negative terminal of diode D2 is connected between switching transistor G4 and capacitor C3.

[0137] The fan IPM module is connected in parallel across capacitor C3, and the switching transistor G4 is used as a second controllable switching transistor.

[0138] Under this first PFC circuit, its working principle is as follows: After the power supply is rectified, it starts from the first end of the power rectifier module, passes through inductor L3, switching transistor G4, and capacitor C3 in sequence, and returns to the second end of the power rectifier module. During this process, capacitor C3 stores energy and provides energy to the fan IPM module. The polarity of the output voltage is positive at the top and negative at the bottom.

[0139] At the same time, capacitor C4 forms a loop current through switch G4, capacitor C3, and inductor L4, which superimposes voltage on capacitor C3, thus boosting the voltage. It also provides current to inductor L4. At this time, capacitor C4 is powered, with the polarity being positive at the top and negative at the bottom, and diode D2 is in the off state.

[0140] As can be seen from the above-mentioned working process of the first PFC circuit, in the event of a failure of the switching transistor G3, the first PFC circuit can work independently and perform the corresponding boost action to maintain the power supply to the fan IPM module, thus preventing the air conditioner from shutting down. The first PFC circuit can adapt to working under low power conditions and realize buck and boost control to meet the usage requirements of the fan under low power conditions.

[0141] Please see the appendix Figure 8 In the second PFC circuit module of the present invention, the second PFC circuit includes inductor L3, inductor L4, capacitor C3, capacitor C4, and diode D2.

[0142] One end of inductor L3 is connected to the first end of the power rectifier module, the other end of inductor L3 is connected to one end of capacitor C4, the other end of capacitor C4 is connected to one end of inductor L4, and the other end of inductor L4 is connected to the second end of the power rectifier module.

[0143] The positive terminal of diode D2 is connected between capacitor C4 and inductor L4, the negative terminal of diode D2 is connected to one end of capacitor C3, and the other end of capacitor C3 is connected to the second terminal of the power rectifier module.

[0144] The fan IPM module is connected in parallel across capacitor C3.

[0145] The working principle of the second PFC circuit is as follows: After the power supply is rectified, it starts from the first end of the power rectifier module, passes through inductor L3, capacitor C4, diode D2, and capacitor C3 in sequence, and returns to the second end of the power rectifier module. During this process, capacitor C3 stores energy and provides energy to the fan IPM module. The polarity of the output voltage is positive at the top and negative at the bottom.

[0146] At the same time, inductor L4 provides energy, which passes through diode D2 and capacitor C3 in sequence and returns to inductor L4 to form a loop current. This current is superimposed on the voltage of capacitor C3, thus boosting the voltage. The output voltage of inductor L4 is positive at the top and negative at the bottom.

[0147] As can be seen from the above-described working process of the second PFC circuit, even if switching transistors G3 and G4 are damaged, the second PFC circuit can work independently and perform corresponding boosting actions to maintain power supply to the fan IPM module, thus preventing the air conditioner from shutting down. This second PFC circuit can adapt to working under low power conditions and realize buck and boost control to meet the usage requirements of the fan under low power conditions.

[0148] Please see the appendix Figure 9 In the second PFC circuit module of the present invention, the third PFC circuit includes inductor L3, inductor L4, capacitor C3, capacitor C4, diode D2, and switching transistor G3.

[0149] One end of inductor L3 is connected to the first end of the power rectifier module, and the other end of inductor L3 is connected to one end of switch G3. The other end of switch G3 is connected to the second end of the power rectifier module.

[0150] One end of capacitor C4 is connected between inductor L3 and switching transistor G3, and the other end of capacitor C4 is connected to one end of inductor L4. The other end of inductor L4 is connected to the second terminal of the power rectifier module. The positive terminal of diode D2 is connected between capacitor C4 and inductor L4, and the negative terminal of diode D2 is connected to one end of capacitor C3. The other end of capacitor C3 is connected between inductor L4 and the second terminal of the power rectifier module.

[0151] The fan IPM module is connected in parallel across capacitor C3, and the switching transistor G3 is used as the first controllable switching transistor.

[0152] The working principle of this third PFC circuit is as follows: After the power supply is rectified, it starts from the first end of the power rectifier module, passes through inductor L3 and switching transistor G3 in sequence to form a power supply loop, charging inductor L3 and increasing the current. At the same time, inductor L4 passes through diode D2 and capacitor C3 to form a current loop, charging capacitor C3. At the same time, capacitor C3 provides energy to the fan IPM module. The polarity of the output voltage is positive at the top and negative at the bottom.

[0153] As can be seen from the above-described working process of the third PFC circuit, in the event of a failure of the switching transistor G2, the third PFC circuit can work independently and perform corresponding boosting actions to maintain power supply to the fan IPM module, thus preventing the air conditioner from shutting down. This third PFC circuit can adapt to high-power operation and achieve buck and boost control, meeting the needs of the fan under high-power conditions.

[0154] As can be seen from the above description of the first PFC circuit, the second PFC circuit, and the third PFC circuit, when either the first or the second controllable switch is damaged, or when both the first and the second controllable switch are damaged, the present invention can maintain the continuous operation of the PFC circuit module by conducting the corresponding PFC circuit, thereby achieving uninterrupted operation and avoiding the problem of air conditioner shutdown.

[0155] The above situations describe the abnormal damage to the first and second controllable switching transistors. When the first and second controllable switching transistors are normal, the present invention can also provide different outputs to the compressor IPM module by actively controlling the conduction state of the first and second controllable switching transistors.

[0156] Please see the appendix Figure 5 In this invention, when the switching transistors G3 and G4 are in normal state, the control flow of the second PFC circuit module is as follows: when the fan speed is lower than the second threshold speed, the first PFC circuit or the second PFC circuit is controlled to work.

[0157] When the fan speed is higher than the second threshold speed, the third PFC circuit is activated.

[0158] As mentioned above, the first PFC circuit and the second PFC circuit are generally suitable for control under low power conditions. This invention can determine whether the fan needs to be controlled under low power conditions or high power conditions by judging the second threshold speed. If the speed is lower than the second threshold speed, it is determined that the fan is suitable for control under low power conditions. Then, by actively controlling the switch G3 to turn off, or by simultaneously controlling the switch G3 and the switch G4 to turn off, the second PFC circuit module can work in the first PFC circuit or the second PFC circuit, which can meet the control requirements of the fan at the current speed.

[0159] Similarly, if the fan speed is higher than the second threshold speed, it is determined that the fan is suitable for high-power control at this time. Then, by actively controlling the switch G4 to turn off, the second PFC circuit module is made to work in the third PFC circuit, which can meet the control requirements of the fan at the current speed.

[0160] The second threshold speed is set to 70% of the fan's maximum speed.

[0161] Based on the above solution, this invention can actively control the conduction state of switching transistors G3 and G4 in combination with the fan speed when neither of them is damaged, thereby switching the operation of the first PFC circuit, the second PFC circuit, and the third PFC circuit, which can adapt to the control requirements of the fan at different speeds.

[0162] Furthermore, in this invention, the first controllable switch and the second controllable switch can be IGBTs or MOSFETs;

[0163] Based on the above solution, this invention can avoid the problem of IGBT or MOSFET being damaged due to excessive stress, thereby affecting the operation of the air conditioner.

[0164] The present invention also proposes an air conditioner having the above-mentioned uninterrupted PFC circuit.

[0165] It should be noted that the main loads that need to be controlled in an air conditioner are the compressor and the fan. This invention can also be applied to other products, only requiring adjustment of the corresponding controlled loads. In addition, the integrated form adopted in this invention integrates the compressor IPM module and the fan IPM module into the same power rectifier module. In other embodiments of this invention, they can also be separated and set separately, which can also achieve uninterrupted control.

[0166] Compared with the prior art, the present invention has at least the following beneficial effects:

[0167] This invention divides the PFC circuit module into a first PFC circuit, a second PFC circuit, and a third PFC circuit, which are activated corresponding to the on states of the first and second controllable switches. This enables automatic switching of the first PFC circuit when the first controllable switch fails, automatic switching of the second PFC circuit when both the first and second controllable switches fail, and automatic switching of the third PFC circuit when the second controllable switch fails. This ensures the normal operation of the PFC circuit module regardless of which controllable switch fails, or even both controllable switches fail simultaneously, guaranteeing continuous operation and preventing damage to the controllable switches due to excessive stress, which could affect air conditioning operation.

[0168] It should be noted that the terminology used above is for describing specific embodiments only and is not intended to limit the exemplary embodiments of the present invention. When the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof. The order of execution of actions, steps, etc., in the apparatus and methods described in the specification and drawings can be implemented in any order unless a specific order is expressly specified, and as long as the output of the preceding process is not used in the subsequent process. Similar sequential terms used for ease of description do not imply that such an order must be followed.

[0169] Techniques, methods, and apparatus known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and apparatus should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as constraints. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0170] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An uninterrupted power rectifier (PFC) circuit, comprising a power rectifier module and at least one PFC circuit module connected to the power rectifier module, characterized in that, Each of the PFC circuit modules includes a first controllable switch and a second controllable switch, which are used to adjust the operating state of the PFC circuit module. The PFC circuit module includes at least a first operating state when the first controllable switch is in the off state, a second operating state when both the first controllable switch and the second controllable switch are in the off state, and a third operating state when the second controllable switch is in the off state.

2. The uninterrupted PFC circuit according to claim 1, characterized in that, Each of the PFC circuit modules includes a first PFC circuit, a second PFC circuit, and a third PFC circuit; When the first PFC circuit is working, the PFC circuit module is in the first working state; When the second PFC circuit is working, the PFC circuit module is in the second working state; When the third PFC circuit is working, the PFC circuit module is in the third working state.

3. The uninterrupted PFC circuit according to claim 2, characterized in that, The PFC circuit module includes a first PFC circuit module for powering the compressor IPM module. In the first PFC circuit module, the first PFC circuit includes inductor L1, inductor L2, capacitor C1, capacitor C2, diode D1, and switching transistor G2. One end of the inductor L1 is connected to the first end of the power rectifier module, the other end of the inductor L1 is connected to one end of the switching transistor G2, the other end of the switching transistor G2 is connected to one end of the capacitor C2, and the other end of the capacitor C2 is connected to the second end of the power rectifier module. One end of capacitor C1 is connected between inductor L1 and switching transistor G2, and the other end of capacitor C1 is connected to one end of inductor L2. The other end of inductor L2 is connected to the second end of the power rectifier module. The positive terminal of diode D1 is connected between capacitor C1 and inductor L2, and the negative terminal of diode D1 is connected between switch G2 and capacitor C2. The compressor IPM module is connected in parallel across the capacitor C2, and the switching transistor G2 is used as the second controllable switching transistor.

4. The uninterrupted PFC circuit according to claim 3, characterized in that, In the first PFC circuit module, the second PFC circuit includes inductor L1, inductor L2, capacitor C1, capacitor C2, and diode D1; One end of the inductor L1 is connected to the first end of the power rectifier module, the other end of the inductor L1 is connected to one end of the capacitor C1, the other end of the capacitor C1 is connected to one end of the inductor L2, and the other end of the inductor L2 is connected to the second end of the power rectifier module. The positive terminal of diode D1 is connected between capacitor C1 and inductor L2, the negative terminal of diode D1 is connected to one end of capacitor C2, and the other end of capacitor C2 is connected to the second terminal of the power rectifier module. The compressor IPM module is connected in parallel across the capacitor C2.

5. The uninterrupted PFC circuit according to claim 4, characterized in that, In the first PFC circuit module, the third PFC circuit includes inductor L1, inductor L2, capacitor C1, capacitor C2, diode D1, and switching transistor G1; One end of the inductor L1 is connected to the first end of the power rectifier module, the other end of the inductor L1 is connected to one end of the switching transistor G1, and the other end of the switching transistor G1 is connected to the second end of the power rectifier module. One end of capacitor C1 is connected between inductor L1 and switching transistor G1, and the other end of capacitor C1 is connected to one end of inductor L2. The other end of inductor L2 is connected to the second terminal of the power rectifier module. The positive terminal of diode D1 is connected between capacitor C1 and inductor L2, and the negative terminal of diode D1 is connected to one end of capacitor C2. The other end of capacitor C2 is connected between inductor L2 and the second terminal of the power rectifier module. The compressor IPM module is connected in parallel across the capacitor C2, and the switching transistor G1 is used as the first controllable switching transistor.

6. The uninterrupted PFC circuit according to claim 5, characterized in that, When the switching transistors G1 and G2 are in normal operation, the first PFC circuit module is configured to control the first PFC circuit or the second PFC circuit to operate when the compressor speed is lower than the first threshold speed. When the compressor speed is higher than the first threshold speed, the third PFC circuit is controlled to work.

7. The uninterrupted PFC circuit according to claim 2, characterized in that, The PFC circuit module also includes a second PFC circuit module for powering the wind turbine IPM module. In the second PFC circuit module, the first PFC circuit includes inductor L3, inductor L4, capacitor C3, capacitor C4, diode D2, and switching transistor G4. One end of the inductor L3 is connected to the first end of the power rectifier module, the other end of the inductor L3 is connected to one end of the switching transistor G4, the other end of the switching transistor G4 is connected to one end of the capacitor C3, and the other end of the capacitor C3 is connected to the second end of the power rectifier module. One end of capacitor C4 is connected between inductor L3 and switching transistor G4, and the other end of capacitor C4 is connected to one end of inductor L4. The other end of inductor L4 is connected to the second end of the power rectifier module. The positive terminal of diode D2 is connected between capacitor C4 and inductor L4, and the negative terminal of diode D2 is connected between switch G4 and capacitor C3; The wind turbine IPM module is connected in parallel across the capacitor C3, and the switching transistor G4 is used as the second controllable switching transistor.

8. The uninterrupted PFC circuit according to claim 7, characterized in that, In the second PFC circuit module, the second PFC circuit includes inductor L3, inductor L4, capacitor C3, capacitor C4, and diode D2; One end of the inductor L3 is connected to the first end of the power rectifier module, the other end of the inductor L3 is connected to one end of the capacitor C4, the other end of the capacitor C4 is connected to one end of the inductor L4, and the other end of the inductor L4 is connected to the second end of the power rectifier module. The positive terminal of diode D2 is connected between capacitor C4 and inductor L4, the negative terminal of diode D2 is connected to one end of capacitor C3, and the other end of capacitor C3 is connected to the second terminal of the power rectifier module. The wind turbine IPM module is connected in parallel across the capacitor C3.

9. The uninterrupted PFC circuit according to claim 8, characterized in that, In the second PFC circuit module, the third PFC circuit includes inductor L3, inductor L4, capacitor C3, capacitor C4, diode D2, and switching transistor G3; One end of the inductor L3 is connected to the first end of the power rectifier module, the other end of the inductor L3 is connected to one end of the switching transistor G3, and the other end of the switching transistor G2 is connected to the second end of the power rectifier module. One end of capacitor C4 is connected between inductor L3 and switching transistor G3, and the other end of capacitor C4 is connected to one end of inductor L4. The other end of inductor L4 is connected to the second terminal of the power rectifier module. The anode of diode D2 is connected between capacitor C4 and inductor L4, and the cathode of diode D2 is connected to one end of capacitor C3. The other end of capacitor C3 is connected between inductor L4 and the second terminal of the power rectifier module. The wind turbine IPM module is connected in parallel across the capacitor C3, and the switching transistor G3 is used as the first controllable switching transistor.

10. The uninterrupted PFC circuit according to claim 9, characterized in that, When the switching transistors G3 and G4 are in normal operation, the second PFC circuit module is configured to control the first PFC circuit or the second PFC circuit to operate when the fan speed is lower than the second threshold speed. When the fan speed is higher than the second threshold speed, the third PFC circuit is controlled to work.

11. The uninterrupted PFC circuit according to claim 1, characterized in that, The first controllable switch and the second controllable switch are IGBTs or MOSFETs.

12. An air conditioner, characterized in that, The air conditioner has an uninterrupted PFC circuit as described in any one of claims 1 to 11.

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