Air conditioner

Abstract

The invention provides an air conditioner which comprises a three-phase motor, a power module electrically connected with the three-phase motor, a driving circuit electrically connected with the power module, a switching power supply providing electric energy for the driving circuit, a first bootstrap circuit, a second bootstrap circuit, a third bootstrap circuit and a controller electrically connected with the driving circuits. After the controller is powered on, when a first detection signal of each lower driving circuit is a set level, the controller sends an electric signal to each lower driving circuit, and the IGBT corresponding to each lower driving circuit is conducted; after the first bootstrap capacitor, the second bootstrap capacitor and the third bootstrap capacitor are charged, the controller stops sending the electric signal; and when the second detection signal of each upper driving circuit is the set level, each upper driving circuit is judged to be normal at the moment, and the controller works normally. The six driving circuits are powered by one switching power supply in a mode of setting the bootstrap circuit, so that normal work of the controller is realized, the design cost of the transformer is reduced, and the layout design is relatively simple.

Description

Technical Field

[0001] The present invention relates to the technical field of household appliances, and in particular to an air conditioner. Background Art

[0002] At present, the compressor or DC fan of the air conditioner is generally driven by a three-phase motor. The three-phase motor includes three upper bridge arms and three lower bridge arms, and each of them is driven by an isolated driver chip.

[0003] The input side and output side of the isolated driver chip are isolated, and the corresponding power supply is also isolated. The output power supply is generally 5V, and the output side power supply is generally 15V. The two power supplies must be reliably isolated to work. The output side power supply 15V of the three lower bridge arms of the variable frequency inverter drive circuit can share one, and the ground of the output side power supply of the three upper bridge arms is floating, so the output side 15V of the driver chip of the upper bridge arm must be isolated separately, so 4 15V power supplies are required.

[0004] The 4-way 15V power supply generally comes from a switching power supply, and the switching transformer needs to output at least 4 15V. The power supply design is complex. At the same time, the electrical clearance and creepage distance of the isolated 4-way 15V control board layout must meet the safety requirements, and the wiring spacing must meet a certain distance. More layout space is required, and strict requirements are placed on the printed circuit board layout design. In addition, after the controller is powered on, the controller MCU first detects the RDY signal of the isolated driver chip. The RDY network of the 6-way isolated driver chip is connected together and sent to the controller. If the power supply 15V of one of the 6 isolated driver chips is abnormal, there is no 15V power supply or the power supply does not reach 15V, the undervoltage protection function will be triggered, and the controller MCU will report a fault and will not work.

[0005] In view of this, this application is filed. Summary of the invention

[0006] The present application provides an air conditioner, which uses a switching power supply to power six drive circuits by setting a bootstrap circuit, can realize normal operation of the controller, reduce the design cost of the transformer, and requires a small wiring space, and the layout design is relatively simple.

[0007] The present application provides an air conditioner, comprising:

[0008] Three-phase motor;

[0009] The power module includes three upper bridge arms and three lower bridge arms electrically connected to the current input terminal of the three-phase motor, which are respectively defined as the U-axis upper bridge arm, the V-axis upper bridge arm, the W-axis upper bridge arm, the U-axis lower bridge arm, the V-axis lower bridge arm and the W-axis lower bridge arm;

[0010] Six driving circuits are defined as U-axis upper driving circuit, V-axis upper driving circuit, W-axis upper driving circuit, U-axis lower driving circuit, V-axis lower driving circuit and W-axis lower driving circuit, corresponding to U-axis upper bridge arm, V-axis upper bridge arm, W-axis upper bridge arm, U-axis lower bridge arm, V-axis lower bridge arm and W-axis lower bridge arm respectively;

[0011] A switching power supply, used to provide power to the drive circuit;

[0012] A first bootstrap circuit is electrically connected to the switch power supply and the U-axis drive circuit, the first bootstrap circuit comprises a first bootstrap capacitor, one end of the first bootstrap capacitor is connected to the U-axis drive circuit and the switch power supply to provide a voltage required by the U-axis drive circuit;

[0013] A second bootstrap circuit is electrically connected to the switch power supply and the V-axis drive circuit, the second bootstrap circuit comprises a second bootstrap capacitor, one end of the second bootstrap capacitor is connected to the V-axis drive circuit and the switch power supply to provide a voltage required by the V-axis drive circuit;

[0014] a third bootstrap circuit electrically connected to the switch power supply and the W-axis drive circuit, the third bootstrap circuit comprising a third bootstrap capacitor, one end of the third bootstrap capacitor being connected to the W-axis drive circuit and the switch power supply to provide a voltage required by the W-axis drive circuit;

[0015] A controller electrically connected to each drive circuit, wherein the controller is configured such that, after the controller is powered on, when the first detection signal of each lower drive circuit is at a set level, the controller sends an electrical signal to each lower drive circuit, and the IGBT corresponding to each lower drive circuit is turned on;

[0016] The first bootstrap capacitor, the second bootstrap capacitor, and the third bootstrap capacitor are charged to supply power to each upper drive circuit, and the controller stops sending electrical signals;

[0017] When the second detection signal of each upper driving circuit is at a set level, it is determined that each upper driving circuit is normal at this time, and the controller works normally.

[0018] In some embodiments of the present application, the first bootstrap circuit further includes:

[0019] A first resistor, one end of which is connected to a switching power supply;

[0020] a first diode, wherein an anode of the first diode is connected to the other end of the first resistor, a cathode of the first diode is connected to one end of the first bootstrap capacitor, and the other end of the first bootstrap capacitor is grounded;

[0021] After the first bootstrap capacitor is fully charged, the voltage across the first bootstrap capacitor is the voltage value of the switching power supply, and the first bootstrap capacitor is used to provide voltage for the U-axis driving circuit.

[0022] In some embodiments of the present application, the second bootstrap circuit further includes:

[0023] A second resistor, one end of which is connected to a switching power supply;

[0024] a second diode, wherein the entire second diode is connected to the other end of the second resistor, the cathode of the second diode is connected to one end of the second bootstrap capacitor, and the other end of the second bootstrap capacitor is grounded;

[0025] After the second bootstrap capacitor is fully charged, the voltage across the second bootstrap capacitor is the voltage value in the switching power supply, and the second bootstrap capacitor is used to provide voltage for the driving circuit on the V axis.

[0026] In some embodiments of the present application, the third bootstrap circuit further includes:

[0027] a third resistor, one end of the third resistor being connected to the switching power supply;

[0028] a third diode, wherein the entire third diode is connected to the other end of the third resistor, the cathode of the third diode is connected to one end of the third bootstrap capacitor, and the other end of the third bootstrap capacitor is grounded;

[0029] After the third bootstrap capacitor is fully charged, the voltage across the third bootstrap capacitor is the voltage value in the switching power supply, and the third bootstrap capacitor is used to provide voltage for the W-axis driving circuit.

[0030] In some embodiments of the present application, the controller is configured to: first send a reset signal to each driving circuit before detecting the first detection signal of each lower driving circuit.

[0031] In some embodiments of the present application, the controller is configured to, when detecting that the first detection signal of each lower drive circuit is not at a set level, determine that at this time, one or a combination of the U-axis lower drive circuit, the V-axis lower drive circuit, and the W-axis lower drive circuit is abnormal, and the controller does not work;

[0032] The first detection signal is related to the receiving voltage of each lower driving circuit.

[0033] In some embodiments of the present application, the electrical signal is a high level signal or a three-way PWM signal.

[0034] In some embodiments of the present application, the controller is configured to, when detecting that the second detection signal of each upper drive circuit is not at a set level, determine that at this time, one or a combination of the U-axis upper drive circuit, the V-axis upper drive circuit, and the W-axis upper drive circuit is abnormal, and the controller does not work;

[0035] The second detection signal is related to the receiving voltage of each upper driving circuit.

[0036] In some embodiments of the present application, the controller is configured such that when an abnormality occurs in one of the first bootstrap circuit, the second bootstrap circuit and the third bootstrap circuit or in a combination thereof, after the controller sends an electrical signal, at least one of the voltages across the first bootstrap capacitor, the second bootstrap capacitor and the third bootstrap capacitor does not meet the voltage value of the switching power supply, and the second detection signal of the upper drive circuit outputs a low level, and it is determined that an abnormality occurs in one of the U-axis drive circuit, the V-axis drive circuit and the W-axis drive circuit or in a combination thereof, and the controller does not work.

[0037] In some embodiments of the present application, two switching power supplies may also be provided, wherein one switching power supply provides voltage for each lower driving circuit, and the other switching power supply provides voltage for each upper driving circuit.

[0038] In the above embodiments, the present application proposes an air conditioner, which includes a three-phase motor, a power module electrically connected to the three-phase motor, a drive circuit electrically connected to the power module, a switching power supply for providing power to the drive circuit, a first bootstrap circuit, a second bootstrap circuit, a third bootstrap circuit and a controller electrically connected to each drive circuit, wherein the power module includes three upper bridge arms and three lower bridge arms electrically connected to the current input end of the three-phase motor, and the three upper bridge arms and the three lower bridge arms are respectively defined as the U-axis upper bridge arm, the V The six driving circuits are respectively defined as the U-axis upper driving circuit, the V-axis upper driving circuit, the W-axis upper driving circuit, the U-axis lower driving circuit, the V-axis lower driving circuit and the W-axis lower driving circuit, and the above driving circuits correspond to the U-axis upper bridge arm, the V-axis upper bridge arm, the W-axis upper bridge arm, the U-axis lower bridge arm, the V-axis lower bridge arm and the W-axis lower bridge arm respectively; the first bootstrap circuit is electrically connected to the switching power supply and the U-axis upper driving circuit, the first bootstrap circuit includes a first bootstrap capacitor, and the first One end of a bootstrap capacitor is connected to the U-axis drive circuit and the switching power supply to provide the voltage required by the U-axis drive circuit; the second bootstrap circuit is electrically connected to the switching power supply and the V-axis drive circuit, the second bootstrap circuit includes a second bootstrap capacitor, one end of the second bootstrap capacitor is connected to the V-axis drive circuit and the switching power supply to provide the voltage required by the V-axis drive circuit; the third bootstrap circuit is electrically connected to the switching power supply and the W-axis drive circuit, the third bootstrap circuit includes a third bootstrap capacitor, one end of the third bootstrap capacitor is connected to the power supply end of the W-axis drive circuit and the switching power supply to provide the voltage required by the W-axis drive circuit; the controller is configured such that after the controller is powered on, when the first detection signal of each lower drive circuit is a set level, the controller sends an electrical signal to each lower drive circuit, and the IGBT corresponding to each lower drive circuit is turned on; after the first bootstrap capacitor, the second bootstrap capacitor and the third bootstrap capacitor are charged, the controller stops sending the electrical signal; when the second detection signal of each upper drive circuit is a set level, it is determined that each upper drive circuit is normal at this time, and the controller works normally. By using one switching power supply to power six drive circuits by setting a bootstrap circuit, the controller can work normally, the design cost of the transformer is reduced, the switching power supply design is relatively simple, the EMC interference of the controller is small, the required wiring space is small, and the layout design is relatively simple. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0040] Figure 1 is a refrigeration system diagram of an air conditioner provided according to an exemplary embodiment;

[0041] Figure 2 A schematic diagram of connecting an air conditioner and a control device according to an exemplary embodiment;

[0042] Figure 3 A hardware configuration block diagram of an air conditioner provided according to an exemplary embodiment;

[0043] Figure 4 A hardware configuration block diagram of a controller provided according to an exemplary embodiment;

[0044] Figure 5 is a circuit diagram of a power module provided according to an exemplary embodiment;

[0045] Figure 6 is a circuit diagram of a U-axis driving circuit provided according to an exemplary embodiment;

[0046] Figure 7 is another hardware configuration block diagram of an air conditioner provided according to an exemplary embodiment;

[0047] Figure 8 Control logic for operating a controller provided in accordance with an exemplary embodiment;

[0048] Fig. 9 is a circuit diagram of a V-axis driving circuit provided according to an exemplary embodiment;

[0049] Fig.10 is a circuit diagram of a W-axis driving circuit provided according to an exemplary embodiment;

[0050] Fig.11 Control logic for operating a controller provided in accordance with an exemplary embodiment;

[0051] Fig.12 is a circuit diagram of a U-axis driving circuit provided according to an exemplary embodiment;

[0052] Fig.13 is a circuit diagram of a V-axis driving circuit provided according to an exemplary embodiment;

[0053] Fig.14 is a circuit diagram of a W-axis driving circuit provided according to an exemplary embodiment;

[0054] Fig.15 is a circuit diagram of a controller provided according to an exemplary embodiment;

[0055] In the above figures:

[0056] Air conditioner 100; compressor 1; condenser 2; expansion valve 3; evaporator 4;

[0057] Control device 5; power module 6; control module 7; controller 71; drive circuit 72;

[0058] U-axis driving circuit 721; V-axis driving circuit 722; W-axis driving circuit 723;

[0059] U-axis lower drive circuit 724; V-axis upper drive circuit 725; W-axis upper drive circuit 726;

[0060] Bridge arm 61 on U axis; bridge arm 62 on V axis; bridge arm 63 on W axis;

[0061] U-axis lower bridge arm 64; V-axis lower bridge arm 65; W-axis lower bridge arm 66;

[0062] Processor 83; memory 82; communication interface 84; bus 81;

[0063] A first bootstrap circuit 91; a second bootstrap circuit 92; a third bootstrap circuit 93; a switching power supply 10;

[0064] Three-phase motor 11; first bootstrap capacitor C1; first resistor R1; first diode V1;

[0065] A second bootstrap capacitor C2; a second resistor R2; a second diode V2;

[0066] A third bootstrap capacitor C3; a third resistor R3; and a third diode V3. DETAILED DESCRIPTION

[0067] The present invention is described in detail below by way of exemplary embodiments. However, it should be understood that elements, structures, and features in one embodiment may also be beneficially combined in other embodiments without further description.

[0068] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0069] The terms "first", "second" are used only for descriptive purposes and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined as "first", "second" may explicitly or implicitly include one or more of the features.

[0070] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0071] The present application embodiment provides an air conditioner 100, referring to Figure 1 The air conditioner 100 includes a refrigeration system for exchanging heat with indoor air to achieve cooling or heating needs.

[0072] The refrigeration system includes a compressor 1, a condenser 2, an expansion valve 3 and an evaporator 4. In the present application, the air conditioner 100 performs a refrigeration cycle of the air conditioner 100 by using the compressor 1, the condenser 2, the expansion valve 3 and the evaporator 4. The refrigeration cycle includes a series of processes involving compression, condensation, expansion and evaporation, and supplies refrigerant to the conditioned and heat-exchanged air.

[0073] The compressor 1 compresses the refrigerant gas in a high temperature and high pressure state and discharges the compressed refrigerant gas. The discharged refrigerant gas flows into the condenser 2. The condenser 2 condenses the compressed refrigerant into a liquid phase, and heat is released to the surrounding environment through the condensation process.

[0074] The expansion valve 3 expands the high-temperature and high-pressure liquid refrigerant condensed in the condenser 2 into a low-pressure liquid refrigerant. The evaporator 4 evaporates the refrigerant expanded in the expansion valve 3 and returns the low-temperature and low-pressure refrigerant gas to the compressor 1.

[0075] The evaporator 4 can achieve a refrigeration effect by utilizing the latent heat of evaporation of the refrigerant to exchange heat with the material to be cooled. In the entire cycle, the air conditioner 100 can adjust the temperature of the indoor space.

[0076] The outdoor unit of the air conditioner 100 refers to a portion of a refrigeration cycle including the compressor 1 and an outdoor heat exchanger, the indoor unit of the air conditioner 100 includes an indoor heat exchanger, and the expansion valve 3 may be provided in the indoor unit or the outdoor unit.

[0077] The indoor heat exchanger and the outdoor heat exchanger function as the condenser 2 or the evaporator 4. When the indoor heat exchanger functions as the condenser 2, the air conditioner 100 functions as a heater in a heating mode, and when the indoor heat exchanger functions as the evaporator 4, the air conditioner 100 functions as a cooler in a cooling mode.

[0078] The air conditioner 100 in the present application can be configured as an integrated unit or a split unit, and can be configured as a cabinet unit or a wall-mounted unit.

[0079] Taking an indoor wall mounted unit (not shown in the figure) as an example, the indoor wall mounted unit is usually installed at a location such as an indoor wall. For another example, an indoor cabinet unit (not shown in the figure) is also a form of indoor unit.

[0080] Taking a split unit as an example, the air conditioner 100 includes an indoor unit and an outdoor unit, wherein the outdoor unit is usually arranged outdoors for heat exchange in the indoor environment.

[0081] In addition, if Figure 2 As shown in the figure, the air conditioner 100 is provided with a controller 71 to control the operation of various components in the air conditioner 100 so that the various components of the air conditioner 100 can be operated to realize various predetermined functions of the air conditioner 100. Among them, the air conditioner 100 is also provided with a control device 5. For example, the control device 5 is specifically configured as a remote controller, which has the function of communicating with the controller 71 using infrared or other communication methods, for example. The remote controller is used for the user to perform various controls on the air conditioner 100 and realize the interaction between the user and the air conditioner 100.

[0082] Reference Figure 3 , the air conditioner 100 of the embodiment of the present application includes a compressor 1, a power module 6 and a control module 7;

[0083] The compressor 1 has a three-phase motor 11, which includes three windings corresponding to the U-axis current, the V-axis current and the W-axis current respectively;

[0084] The power module 6 is connected to the three-phase motor 11 and is used to power the three-phase motor 11. In order to match the three windings of the three-phase motor 11, the power module 6IPM includes six transistors. Figure 3 As shown, the power supply to the three-phase motor 11 is controlled by the power module 6 .

[0085] The control module 7 includes a drive circuit 72 and a controller 71. The drive circuit 72 outputs a three-phase PWM signal to the power module 6. The drive circuit 72 outputs three groups of PWM signals to the control ends of the six transistors to drive the six transistors to be turned on and off, thereby supplying power to the three windings of the three-phase motor 11. The controller 71 is electrically connected to each drive circuit 72. The controller 71 detects the state of the drive circuit 72 and controls the working state of the drive circuit 72 to control the working state of the three-phase motor 11.

[0086] In the embodiment shown in the present application, the controller 71 refers to a device that can generate an operation control signal according to the instruction operation code and the timing signal to instruct the air conditioner 100 to execute the control instruction. For example, in response to receiving a power-on instruction issued by the user, the controller 71 can execute an operation related to the object selected by the power-on instruction.

[0087] The present application also provides a hardware structure diagram of a controller 71, such as Figure 4 As shown, the controller 71 includes a processor 83, and optionally, further includes a memory 82 and a communication interface 84 connected to the processor 83. The processor 83, the memory 82 and the communication interface 84 are connected via a bus 81.

[0088] The processor 83 may be a central processing unit 83 (CPU), a general processor 83, a network processor 83 (NP), a digital signal processor 83 (DSP), a microprocessor 83, a microcontroller 718, a programmable logic device (PLD), or any combination thereof. The processor 83 may also be any other device having a processing function, such as a circuit, a device, or a software module. The processor 83 may also include multiple CPUs, and the processor 83 may be a single-CPU processor 83 or a multi-CPU processor 83. The processor 83 here may refer to one or more devices, circuits, or processing cores for processing data (such as computer program instructions).

[0089] The memory 82 may be a read-only memory 82 (ROM) or other types of static storage devices that can store static information and instructions, a random access memory 82 (RAM) or other types of dynamic storage devices that can store information and instructions, or an electrically erasable programmable read-only memory 82 (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical disc, laser disc, optical disc, digital versatile disc, Blu-ray disc, etc.), a magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store the desired program code in the form of an instruction or data structure and can be accessed by a computer, and the present embodiment of the application does not impose any restrictions on this. The memory 82 may exist independently or be integrated with the processor 83. Among them, the memory 82 may contain a computer program code. The processor 83 is used to execute the computer program code stored in the memory 82, thereby realizing the control method of the multi-split air conditioner 100100 system provided in the embodiment of the present application.

[0090] The communication interface 84 can be used to communicate with other devices or communication networks (such as Ethernet, radio access network (RAN), wireless local area networks (WLAN), etc. The communication interface 84 can be a module, a circuit, a transceiver or any device that can achieve communication.

[0091] The bus 81 may be a peripheral component interconnect (PCI) bus 81 or an extended industry standard architecture (EISA) bus 81, etc. The bus 81 may be divided into an address bus 81, a data bus 81, a control bus 81, etc. For ease of representation, Fig.11 Although only one thick line is used in the figure, it does not mean that there is only one bus 81 or only one type of bus 81.

[0092] In some embodiments of the present application, reference Figure 5 The power module 6 includes three upper bridge arms and three lower bridge arms, which are respectively defined as the U-axis upper bridge arm 61 (shown as Upd), the V-axis upper bridge arm 62 (shown as Vpd), the W-axis upper bridge arm 63 (shown as Wpd), the U-axis lower bridge arm 64 (shown as Und), the V-axis lower bridge arm 65 (shown as Vnd) and the W-axis lower bridge arm 66 (shown as Wnd). The corresponding upper bridge arms and lower bridge arms will correspond to a winding of the three-phase motor 11. Specifically, the U-axis upper bridge arm 61 and the U-axis lower bridge arm 64 correspond to one winding, the V-axis upper bridge arm 62 and the V-axis lower bridge arm 65 correspond to one winding, and the W-axis upper bridge arm 63 and the W-axis lower bridge arm 66 correspond to one winding.

[0093] Exemplarily, each bridge arm includes a combination circuit of a transistor and a diode. Taking the bridge arm 61 on the U axis as an example, the transistor is set as an NPN type tube, the base of the transistor is connected to the output port of the driving circuit 721 on the U axis, the emitter of the transistor is electrically connected to the positive pole of the diode, and the collector of the transistor is electrically connected to the negative pole of the diode. The emitter of the transistor and the positive pole of the diode are electrically connected to the U axis current input terminal of the three-phase motor 11. Similarly, the bridge arm 62 on the V axis is electrically connected to the V axis current output terminal, and the bridge arm 63 on the W axis is electrically connected to the W axis current output terminal.

[0094] In order to cooperate with the six bridge arms, six driving circuits 72 are provided. By setting PWM signals to drive the on and off of transistors in the six bridge arms, the six driving circuits 72 are respectively a U-axis driving circuit 721, a V-axis driving circuit 722, a W-axis driving circuit 723, a U-axis lower driving circuit 724, a V-axis driving circuit 722 and a W-axis driving circuit 723, which correspond to the U-axis upper bridge arm 61, the V-axis upper bridge arm 62, the W-axis upper bridge arm 63, the U-axis lower bridge arm 64, the V-axis lower bridge arm 65 and the W-axis lower bridge arm 66 respectively. The driving circuit 72 will output a PWM signal to the corresponding bridge arm to drive the on and off of the bridge arm, thereby realizing power supply for the three windings of the motor.

[0095] In some technical solutions, the six drive circuits 72 require four isolated power supplies to complete the power supply. For example, the power supply voltage of the power supply is 15 V. The four 15 V power supplies generally come from the switching power supply 10, and the switching transformer needs to output at least four 15 V voltages. The power supply design of this solution is complicated. At the same time, the creepage distance of the electrical clearance of the four power supplies in the layout wiring must meet the requirements of the installation rules, and the wiring spacing must meet a certain distance, which has strict requirements on the layout design of the printed circuit board.

[0096] In some implementations of this embodiment, the U-axis upper drive circuit 721, the V-axis upper drive circuit 722, and the W-axis upper drive circuit 723 form a network, and output a RDY-UP signal to determine whether the three upper drive circuits 72 are working properly. The U-axis lower drive circuit 724, the V-axis upper drive circuit 722, and the W-axis upper drive circuit 723 output a RDY-DOWN signal to determine whether the three lower drive circuits 72 are working properly.

[0097] Compared with the related art in which the RDY of the six drive circuits 72 are formed into the same network and the RDY pin is used for open-drain output, the above setting divides the six drive circuits 72 into two networks in the present application, which can accurately judge the working status of the upper bridge arm and the lower bridge arm respectively, and can judge the working status of the upper bridge arm and the lower bridge arm respectively to realize the whole machine control. At the same time, by dividing into two networks for judgment, the fault location can be confirmed more accurately.

[0098] Each driving circuit 72 includes a driving chip and a peripheral circuit. Figure 6 , the U-axis driving circuit 721 is taken as an example for explanation.

[0099] The pins of the driver chip include IN+, RDY, / RST, VCC1, VCC2, OUT, GND1 and GND2, among which IN+ is electrically connected to the signal output terminal UP of the controller 71, RDY is electrically connected to the signal detection terminal RDY of the controller 71, / RST is electrically connected to the reset signal output terminal / RST-1 of the controller 71, VCC1 is connected to a 5V voltage, GND1 and GND2 are grounded, VCC2 is connected to a 15V power supply, and a capacitor C1 is connected in series between VCC2 and GND2. The OUT port is used to output a PWM signal to the upper bridge arm 61 of the U axis to control the working state of the upper bridge arm 61 of the U axis.

[0100] The driver chip self-detects the power supply voltages VCC1 and VCC2, and outputs a high level when the voltage is normal. The implementation method is: open-drain output, relying on the external circuit pull-up resistor to obtain a high level, and notifying the controller 71 of the status through the RDY port, and can receive controller 71 signals from the controller 71 to work.

[0101] If the voltages of VCC 1 and VCC2 are abnormal, including no voltage or voltage deviation reaching the undervoltage protection value of the driver chip, the driver chip will output a low level to the controller 71 through the RDY port, informing the controller 71 that the driver chip status is abnormal. After the controller 71 receives the RDY signal as a low level signal, it will not control the driver chip to work, and the whole machine will report a fault.

[0102] When the power supply of the driver chip returns to normal, the RDY pin of the driver chip outputs a high level. After the controller 71 receives the high level, the controller 71 sends an RST reset signal to the driver chip. After the driver chip receives the reset signal from the controller 71, it enters a normal working state.

[0103] In the embodiment of the present application, a technical solution is proposed in which six driving circuits 72 are powered by one power supply, and the power supply can realize normal operation of the power module 6 through the control logic corresponding to the bootstrap voltage.

[0104] In some implementations of this embodiment, refer to Figure 7 The air conditioner 100 also includes a first bootstrap circuit 91, a second bootstrap circuit 92, and a third bootstrap circuit 93. The first bootstrap circuit 91 is arranged at the power supply end of the U-axis driving circuit 721, and is used to provide electric energy for the U-axis driving circuit 721; the second bootstrap circuit 92 is arranged at the power supply end of the V-axis driving circuit 722, and is used to provide electric energy for the V-axis driving circuit 722; the third bootstrap circuit 93 is arranged at the power supply end of the W-axis driving circuit 723, and is used to provide electric energy for the W-axis driving circuit 723.

[0105] The controller 71 is configured as follows: after the controller 71 is powered on, when the first detection signal of each lower driving circuit 72 is at a set level, the controller 71 sends an electrical signal to each lower driving circuit 72, and the IGBT corresponding to each lower driving circuit 72 is turned on; the first bootstrap capacitor C1 in the first bootstrap circuit 91, the second bootstrap capacitor C2 in the second bootstrap circuit 92, and the third bootstrap capacitor C3 in the third bootstrap circuit 93 are fully charged, and the voltages at both ends of the corresponding bootstrap capacitors meet the voltages required by the corresponding driving circuits 72 to supply power to each upper driving circuit, and the controller 71 stops sending the above electrical signals. When the second detection signal of each upper driving circuit 72 is at a set level, it is determined that each upper driving circuit 72 is normal at this time, and the controller 71 is working normally.

[0106] Through the above steps, the pins of the driving circuit 72 of the three upper bridge arms and the pins of the driving circuit 72 of the three lower bridge arms are separately subjected to logic detection control, and thereby it is determined whether the driving circuit 72 is working normally, for example, whether it is powered normally, so as to achieve reliable startup of the entire air conditioner 100.

[0107] In some implementations, the electrical signal is a high level or a three-way PWM signal. Fig.15 The three PWM signals are UN, VN, and WN, which are used to control the driving circuits 72 of the three lower bridge arms.

[0108] In some implementations of this embodiment, the controller 71 is configured to, when detecting that the first detection signal of each lower drive circuit 72 is not at a set level, determine that at this time, one or a combination of the U-axis lower drive circuit 724, the V-axis lower drive circuit 725 and the W-axis lower drive circuit 726 is abnormal, and the controller 71 does not work;

[0109] It should be noted that the first detection signal is related to the receiving voltage of each lower driving circuit 72 .

[0110] In some implementations of this embodiment, the controller 71 is configured to, when detecting that the second detection signal of each upper drive circuit 72 is not at a set level, determine that at this time, one or a combination of the U-axis upper drive circuit 721, the V-axis upper drive circuit 722 and the W-axis upper drive circuit 723 is abnormal, and the controller 71 does not work;

[0111] It should be noted that the second detection signal is related to the receiving voltage of each upper driving circuit 72 .

[0112] In some embodiments of the present application, the controller 71 is configured such that when an abnormality occurs in one of the first bootstrap circuit 91, the second bootstrap circuit 92 and the third bootstrap circuit 93 or a combination thereof, after the controller 71 sends an electrical signal, at least one of the voltages across the first bootstrap capacitor C1, the second bootstrap capacitor C2 and the third bootstrap capacitor C3 does not meet the voltage value of the switching power supply 10, and the second detection signal of the upper drive circuit 72 outputs a low level, and it is determined that an abnormality occurs in one of the U-axis drive circuit 721, the V-axis drive circuit 722 and the W-axis drive circuit 723 or a combination thereof, and the controller 71 does not work.

[0113] Reference Figure 12-14 In the present application, the U-axis driving circuit 724 , the V-axis driving circuit 725 and the W-axis driving circuit 726 are directly connected to the switching power supply 10 .

[0114] Reference Figure 8 , illustrating the control logic of the controller 71 in this embodiment.

[0115] The controller 71 is powered on (step S801), and detects the RDY-DOWN signal output by the network composed of the U-axis lower drive circuit 724, the V-axis lower drive circuit 725 and the W-axis lower drive circuit 726 (step S802);

[0116] Determine whether the RDY-DOWN signal is at a high level (step S803);

[0117] In step S803, if the RDY-DOWN signal is at a high level, step S804 is executed, and the controller 71 sends a high level or PWM signal UN, VN, WN for a certain period of time to the U-axis lower drive circuit 724, the V-axis lower drive circuit 725 and the W-axis lower drive circuit 726; then the IGBTs of the three lower bridge arms are turned on (step S805);

[0118] The first bootstrap capacitor C1, the second bootstrap capacitor C2 and the third bootstrap capacitor C3 are charged (step S806);

[0119] The controller 71 stops sending the high level or PWM signals UN, VN, WN (step S807);

[0120] Detecting the RDY-UP signal output by the network consisting of the U-axis driving circuit 721, the V-axis driving circuit 722 and the W-axis driving circuit 723 (step S808);

[0121] Determine whether the RDY-UP signal is at a high level (step S809);

[0122] In step S809, if the RDY-UP signal is at a high level, step S810 is executed, the U-axis drive circuit 721, the V-axis drive circuit 722 and the W-axis drive circuit 723 are in normal state, the controller 71 is in working state, and the power module 6 is controlled to work (step S811);

[0123] In step S809, if the RDY-UP signal is at a low level, step S812 is executed, the U-axis drive circuit 721, the V-axis drive circuit 722 and the W-axis drive circuit 723 are in abnormal states, a fault is reported, and the controller 71 does not work.

[0124] In step S803, if the RDY-DOWN signal is at a low level, step S813 is executed, the U-axis drive circuit 724, the V-axis drive circuit 725 and the W-axis drive circuit 726 are in abnormal states, a fault is reported, and the controller 71 does not work.

[0125] In some implementations of this embodiment, refer to Figure 6 The first bootstrap circuit 91 includes a first bootstrap capacitor C1, a first resistor R1 and a first diode V1. One end of the first bootstrap capacitor C1 is connected to the power supply end of the U-axis driving circuit 721 and the switching power supply 10, and the other end of the first bootstrap capacitor C1 is grounded to generate the voltage required by the U-axis driving circuit 721. The first resistor R1 is used as an isolation resistor. Specifically, one end of the first resistor R1 is connected to the switching power supply 10, the other end of the first resistor R1 is connected to the positive electrode of the first diode V1, the negative electrode of the first diode V1 is connected to one end of the first bootstrap capacitor C1, and the first bootstrap capacitor C1 and the first diode V1 are electrically connected to the power supply end of the driving circuit 72.

[0126] After the first bootstrap capacitor C1 is fully charged, the voltage across the first bootstrap capacitor C1 is the voltage value of the switching power supply 10 . The first bootstrap capacitor C1 is used to provide voltage for the U-axis driving circuit 721 .

[0127] In some implementations of this embodiment, refer to Fig. 9 The second bootstrap circuit 92 includes a second bootstrap capacitor C2, a second resistor R2 and a second diode V2, wherein one end of the second bootstrap capacitor C2 is connected to the power supply end of the U-axis drive circuit 721 and the switching power supply 10, and the other end of the second bootstrap capacitor C2 is grounded to generate the voltage required by the U-axis drive circuit 721. The second resistor R2 is used as an isolation resistor. Specifically, one end of the second resistor R2 is connected to the switching power supply 10, the other end of the second resistor R2 is connected to the positive electrode of the second diode V2, the negative electrode of the second diode V2 is connected to one end of the second bootstrap capacitor C2, and the second bootstrap capacitor C2 and the second diode V2 are electrically connected to the power supply end of the drive circuit 72.

[0128] After the second bootstrap capacitor C2 is fully charged, the voltage across the second bootstrap capacitor C2 is the voltage value of the switching power supply 10 . The second bootstrap capacitor C2 is used to provide voltage for the V-axis driving circuit 722 .

[0129] In some implementations of this embodiment, refer to Fig.10 The third bootstrap circuit 93 includes a third bootstrap capacitor C3, a third resistor R3 and a third diode V3, wherein one end of the third bootstrap capacitor C3 is connected to the power supply end of the U-axis drive circuit 721 and the switching power supply 10, and the other end of the third bootstrap capacitor C3 is grounded to generate the voltage required by the U-axis drive circuit 721. The second resistor R2 is used as an isolation resistor. Specifically, one end of the third resistor R3 is connected to the switching power supply 10, the other end of the third resistor R3 is connected to the positive electrode of the third diode V3, the negative electrode of the third diode V3 is connected to one end of the third bootstrap capacitor C3, and the third bootstrap capacitor C3 and the third diode V3 are electrically connected to the power supply end of the drive circuit 72.

[0130] After the third bootstrap capacitor C3 is fully charged, the voltage across the third bootstrap capacitor C3 is the voltage value of the switching power supply 10 . The third bootstrap capacitor C3 is used to provide voltage for the W-axis driving circuit 723 .

[0131] In some implementations of this embodiment, before detecting the first detection signal of each lower driving circuit 72, a reset signal is first sent to each driving circuit 72. That is, after the controller 71 is powered on, a reset signal is first sent to each driving chip, and the controller 71 detects the RDY-DOWN signal of the three lower driving circuits 72. When the RDY-DOWN signal is detected to be high, a high level is sent to the three lower driving circuits 72 for a certain period of time, and the IGNBTs of the three lower bridge arms corresponding to the power module 6 are turned on, and the internal capacitor of the bootstrap circuit of the corresponding upper bridge arm is charged. When the controller 71 detects that the RDY-UP signal of the three upper driving circuits 72 is high, it is determined that the driving chip status of the three upper bridge arms is normal, and the controller 71 enters the working state to control the power module 6 to work.

[0132] Reference Fig.11 , illustrating another control logic of the controller 71 in this application.

[0133] The controller 71 is powered on (step S1201), and sends a reset signal RST to each drive circuit 72 (step 1214); the RDY-DOWN signal output by the network composed of the U-axis drive circuit 724, the V-axis drive circuit 725 and the W-axis drive circuit 726 is detected (step S1202);

[0134] Determine whether the RDY-DOWN signal is at a high level (step S1203);

[0135] In step S1203, if the RDY-DOWN signal is at a high level, step S1204 is executed, and the controller 71 sends a high level or PWM signal UN, VN, WN for a certain period of time to the U-axis lower drive circuit 724, the V-axis lower drive circuit 725 and the W-axis lower drive circuit 726; then the IGBTs of the three lower bridge arms are turned on (step S1205);

[0136] The first bootstrap capacitor C1, the second bootstrap capacitor C2 and the third bootstrap capacitor C3 are charged (step S1206);

[0137] The controller 71 stops sending the high level or PWM signals UN, VN, WN (step S1207);

[0138] Detecting the RDY-UP signal output by the network consisting of the U-axis driving circuit 721, the V-axis driving circuit 722 and the W-axis driving circuit 723 (step S1208);

[0139] Determine whether the RDY-UP signal is at a high level (step S1209);

[0140] In step S1209, if the RDY-UP signal is at a high level, step S1210 is executed, the U-axis drive circuit 721, the V-axis drive circuit 722 and the W-axis drive circuit 723 are in normal state, the controller 71 is in a common working state, and controls the power module 6 to work (step S1211);

[0141] In step S1209, if the RDY-UP signal is at a low level, step S1212 is executed, the U-axis drive circuit 721, the V-axis drive circuit 722 and the W-axis drive circuit 723 are in abnormal states, a fault is reported, and the controller 71 does not work.

[0142] In step S1203, if the RDY-DOWN signal is at a low level, step S1213 is executed, the U-axis drive circuit 724, the V-axis drive circuit 725 and the W-axis drive circuit 726 are in abnormal states, a fault is reported, and the controller 71 does not work.

[0143] In some embodiments of the present application, two switching power supplies 10 may also be provided, wherein one switching power supply 10 provides voltage for each lower driving circuit 72 , and the other switching power supply 10 provides voltage for each upper driving circuit 72 .

[0144] At the same time, compared with the related art that uses 4 power supplies for power supply, the present application uses 1 power supply for driving work. It can be known that, based on the technical solution of the present application, the technical solution of changing the number of power supplies by changing the number of bootstrap circuits is also within the protection scope of the present application. For example, by using one bootstrap circuit, three power supplies are required for power supply; by using two bootstrap circuits, two power supplies are required for power supply.

[0145] In some embodiments, when two power supplies are used for power supply, the driving circuits 72 of the three upper bridge arms may use one power supply, and the driving circuits 72 of the three lower bridge arms may use another power supply.

[0146] The air conditioner 100 in this embodiment includes a three-phase motor 11, a power module 6 electrically connected to the three-phase motor 11, a drive circuit 72 electrically connected to the power module 6, a switching power supply 10 for providing power to the drive circuit 72, a first bootstrap circuit 91, a second bootstrap circuit 92, a third bootstrap circuit 93 and a controller 71 electrically connected to each drive circuit 72, wherein the power module 6 includes three upper bridge arms and three lower bridge arms electrically connected to the current input end of the three-phase motor 11, and the three upper bridge arms and the three lower bridge arms are respectively defined as a U-axis upper bridge arm 61, a V-axis upper bridge arm 62, a W-axis upper bridge arm 63, and a U-axis lower bridge arm 6 4, the V-axis lower bridge arm 65 and the W-axis lower bridge arm 66, the six drive circuits 72 are respectively defined as the U-axis upper drive circuit 721, the V-axis upper drive circuit 722, the W-axis upper drive circuit 723, the U-axis lower drive circuit 724, the V-axis lower drive circuit 725 and the W-axis lower drive circuit 726, the above drive circuits 72 correspond to the U-axis upper bridge arm 61, the V-axis upper bridge arm 62, the W-axis upper bridge arm 63, the U-axis lower bridge arm 64, the V-axis lower bridge arm 65 and the W-axis lower bridge arm 66; the first bootstrap circuit 91 is electrically connected to the switching power supply 10 and the U-axis upper drive circuit 721, the first bootstrap circuit 91 includes a first bootstrap capacitor C1, the first bootstrap capacitor One end of C1 is connected to the U-axis driving circuit 721 and the switching power supply 10 to provide the voltage required by the U-axis driving circuit 721; the second bootstrap circuit 92 is electrically connected to the switching power supply 10 and the V-axis driving circuit 722, the second bootstrap circuit 92 and includes a second bootstrap capacitor C2, one end of the second bootstrap capacitor C2 is connected to the V-axis driving circuit 722 and the switching power supply 10 to provide the voltage required by the V-axis driving circuit 722; the third bootstrap circuit 93 is electrically connected to the switching power supply 10 and the W-axis driving circuit 723, the third bootstrap circuit 93 includes a third bootstrap capacitor C3, one end of the third bootstrap capacitor C3 is connected to the W-axis driving circuit 721. The power supply end of the circuit 723 and the switching power supply 10 are used to provide the voltage required by the driving circuit 723 on the W axis; the controller 71 is configured such that after the controller 71 is powered on, when the first detection signal of each lower driving circuit 72 is at a set level, the controller 71 sends an electrical signal to each lower driving circuit 72, and the IGBT corresponding to each lower driving circuit 72 is turned on; after the first bootstrap capacitor C1, the second bootstrap capacitor C2 and the third bootstrap capacitor C3 are charged, the controller 71 stops sending the electrical signal; when the second detection signal of each upper driving circuit 72 is at a set level, it is determined that each upper driving circuit 72 is normal at this time, and the controller 71 works normally. By using the above-mentioned switching power supply 10 to power the six driving circuits 72 by setting a bootstrap circuit, the normal operation of the controller 71 can be achieved, the design cost of the transformer is reduced, the design of the switching power supply 10 is relatively simple, the EMC interference of the controller 71 is small, and the required wiring space is small, and the layout design is relatively simple.

[0147] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. An air conditioner, characterized in that: include: Three-phase motor; A power module, which internally includes three upper bridge arms and three lower bridge arms electrically connected to the current input terminal of the three-phase motor, which are respectively defined as a U-axis upper bridge arm, a V-axis upper bridge arm, a W-axis upper bridge arm, a U-axis lower bridge arm, a V-axis lower bridge arm and a W-axis lower bridge arm; Six driving circuits are defined as U-axis upper driving circuit, V-axis upper driving circuit, W-axis upper driving circuit, U-axis lower driving circuit, V-axis lower driving circuit and W-axis lower driving circuit, corresponding to U-axis upper bridge arm, V-axis upper bridge arm, W-axis upper bridge arm, U-axis lower bridge arm, V-axis lower bridge arm and W-axis lower bridge arm respectively; A switching power supply, used to provide power to the driving circuit; a first bootstrap circuit, which is electrically connected to the switching power supply and the U-axis driving circuit, wherein the first bootstrap circuit comprises a first bootstrap capacitor, one end of which is connected to the U-axis driving circuit and the switching power supply to provide a voltage required by the U-axis driving circuit; a second bootstrap circuit electrically connected to the switch power supply and the V-axis drive circuit, the second bootstrap circuit comprising a second bootstrap capacitor, one end of the second bootstrap capacitor being connected to the V-axis drive circuit and the switch power supply to provide a voltage required by the V-axis drive circuit; a third bootstrap circuit, which is electrically connected to the switching power supply and the W-axis driving circuit, the third bootstrap circuit comprising a third bootstrap capacitor, one end of which is connected to the W-axis driving circuit and the switching power supply to provide a voltage required by the W-axis driving circuit; A controller electrically connected to each of the drive circuits, wherein the controller is configured such that, after the controller is powered on, when the first detection signal of each of the lower drive circuits is at a set level, the controller sends an electrical signal to each of the lower drive circuits, and the IGBT corresponding to each of the lower drive circuits is turned on; The first bootstrap capacitor, the second bootstrap capacitor, and the third bootstrap capacitor are fully charged to supply power to each upper driving circuit, and the controller stops sending the electrical signal; When the second detection signal of each upper driving circuit is at a set level, it is determined that each upper driving circuit is normal at this time, and the controller operates normally.

2. The air conditioner according to claim 1, characterized in that: The first bootstrap circuit further comprises: a first resistor, one end of which is connected to the switching power supply; a first diode, wherein an anode of the first diode is connected to the other end of the first resistor, a cathode of the first diode is connected to one end of the first bootstrap capacitor, and the other end of the first bootstrap capacitor is grounded; After the first bootstrap capacitor is fully charged, the voltage across the first bootstrap capacitor is the voltage value of the switching power supply, and the first bootstrap capacitor is used to provide voltage for the U-axis driving circuit.

3. The air conditioner according to claim 2, characterized in that: The second bootstrap circuit further comprises: a second resistor, one end of which is connected to the switching power supply; a second diode, wherein the entirety of the second diode is connected to the other end of the second resistor, a cathode of the second diode is connected to one end of the second bootstrap capacitor, and the other end of the second bootstrap capacitor is grounded; After the second bootstrap capacitor is fully charged, the voltage across the second bootstrap capacitor is the voltage value in the switching power supply, and the second bootstrap capacitor is used to provide voltage for the V-axis driving circuit.

4. The air conditioner according to claim 3, characterized in that: The third bootstrap circuit further comprises: a third resistor, one end of which is connected to the switching power supply; a third diode, wherein the entire third diode is connected to the other end of the third resistor, the cathode of the third diode is connected to one end of the third bootstrap capacitor, and the other end of the third bootstrap capacitor is grounded; After the third bootstrap capacitor is fully charged, the voltage across the third bootstrap capacitor is the voltage value in the switching power supply, and the third bootstrap capacitor is used to provide voltage for the W-axis driving circuit.

5. The air conditioner according to any one of claims 1 to 4, characterized in that: The controller is configured to first send a reset signal to each of the driving circuits before detecting the first detection signal of each of the lower driving circuits.

6. The air conditioner according to any one of claims 1 to 4, characterized in that: The controller is configured to, when detecting that the first detection signal of each lower drive circuit is not at a set level, determine that at this time, one or a combination of the U-axis lower drive circuit, the V-axis lower drive circuit and the W-axis lower drive circuit is abnormal, and the controller does not work; The first detection signal is related to the receiving voltage of each lower driving circuit.

7. The air conditioner according to claim 1, characterized in that: The electrical signal is a high level signal or a three-way PWM signal.

8. The air conditioner according to claim 1, characterized in that: The controller is configured to, when detecting that the second detection signal of each upper drive circuit is not at a set level, determine that at this time, one or a combination of the U-axis upper drive circuit, the V-axis upper drive circuit and the W-axis upper drive circuit is abnormal, and the controller does not work; The second detection signal is related to the receiving voltage of each upper driving circuit.

9. The air conditioner according to claim 8, characterized in that: The controller is configured such that, when an abnormality occurs in one of the first bootstrap circuit, the second bootstrap circuit and the third bootstrap circuit or in a combination thereof, after the controller sends the electrical signal, at least one of the voltages across the first bootstrap capacitor, the second bootstrap capacitor and the third bootstrap capacitor does not meet the voltage value of the switching power supply, the second detection signal of the upper drive circuit outputs a low level, and it is determined that an abnormality occurs in one of the U-axis drive circuit, the V-axis drive circuit and the W-axis drive circuit or in a combination thereof at this time, and the controller does not work.

10. The air conditioner according to claim 1, characterized in that: It can also be configured as two switching power supplies, wherein one switching power supply provides voltage for each lower driving circuit, and the other switching power supply provides voltage for each upper driving circuit.

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