Intelligent power module and variable frequency device

Abstract

The application discloses an intelligent power module and a variable frequency equipment, wherein the intelligent power module comprises a first switching power supply, a second switching power supply, a microcontroller, a high-voltage driving chip and an inverter circuit which are integrally arranged; the first switching power supply is used for reducing and converting a DC bus voltage into a first DC voltage to supply power to the second switching power supply and the high-voltage driving chip; the second switching power supply is used for reducing and converting the first DC voltage into a second DC voltage to supply power to the microcontroller; the microcontroller is used for outputting a control signal to the high-voltage driving chip according to a motor target rotating speed; and the high-voltage driving chip is used for outputting a driving signal to the inverter circuit according to the control signal to drive a power switching element in the inverter circuit to be turned on or turned off. Thus, the design of a module peripheral circuit can be effectively simplified, the volume of an electric control is greatly reduced, the space occupied by the electric control is saved, and the cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of integrated circuit technology, and in particular to an intelligent power module and frequency converter. Background Technology

[0002] Currently, optimizing and improving module integration through intelligent power module design to simplify electronic control design is an important direction for achieving miniaturization of electronic control systems. While intelligent power modules integrate HVIC (High Voltage Integrated Circuit) and a switching power supply for the HVIC, the peripheral circuitry of these modules remains relatively complex, failing to maximize the miniaturization of electronic control systems. Summary of the Invention

[0003] This invention aims to at least partially solve one of the technical problems in the related art. To this end, the first objective of this invention is to provide an intelligent power module that effectively simplifies the design of the module's peripheral circuitry, significantly reduces the size of the electronic control unit, thereby saving space and helping to reduce costs.

[0004] The second objective of this invention is to provide a frequency conversion device.

[0005] To achieve the above objectives, a first aspect of the present invention provides an intelligent power module, comprising an integrated first switching power supply, a second switching power supply, a microcontroller, a high-voltage drive chip, and an inverter circuit. The first switching power supply converts the DC bus voltage into a first DC voltage to power the second switching power supply and the high-voltage drive chip. The second switching power supply converts the first DC voltage into a second DC voltage to power the microcontroller. The microcontroller outputs a control signal to the high-voltage drive chip based on the target speed of the motor. The high-voltage drive chip outputs a drive signal to the inverter circuit based on the control signal to drive the power switching elements in the inverter circuit to turn on or off. The first DC voltage is less than the DC bus voltage, and the second DC voltage is less than the first DC voltage.

[0006] According to an embodiment of the present invention, the intelligent power module converts the DC bus voltage into a first DC voltage via a first switching power supply to power a second switching power supply and a high-voltage drive chip. The second switching power supply then converts the first DC voltage into a second DC voltage to power a microcontroller. The microcontroller outputs a control signal to the high-voltage drive chip based on the target motor speed, and the high-voltage drive chip outputs a drive signal to the inverter circuit based on the control signal, thereby driving the power switching elements in the inverter circuit to turn on or off. This effectively simplifies the design of the module's peripheral circuitry, significantly reducing the size of the electronic control unit (ECU), saving space and contributing to cost reduction.

[0007] According to one embodiment of the present invention, a first switching power supply, a second switching power supply, a microcontroller, and a high-voltage driver chip are integrated together to form an intelligent driver chip.

[0008] According to one embodiment of the present invention, the first switching power supply and the second switching power supply have the same circuit topology and adopt a BUCK circuit structure.

[0009] According to one embodiment of the present invention, a first switching power supply includes: a first switching transistor, a first terminal of which is connected to the positive terminal of a DC bus, and a second terminal of which is connected to a first switching pin; a first logic control unit, which is connected to the control terminal of the first switching transistor, the positive terminal of the DC bus, and the second terminal of the first switching transistor, and the output terminal of the first logic control unit is connected to a first power supply pin, wherein the first logic control unit controls the switching of the first switching transistor to convert the DC bus voltage into a first DC voltage and outputs it through the first power supply pin; and a first diode, the cathode of which is connected to the second terminal of the first switching transistor, and the anode of which is connected to a common ground pin.

[0010] According to one embodiment of the present invention, the second switching power supply includes: a second switching transistor, the first end of which is connected to the output terminal of a first logic control unit, and the second end of which is connected to a second switching pin; a second logic control unit, which is connected to the control terminal of the second switching transistor, the output terminal of the first logic control unit, and the second end of the second switching transistor, respectively, and the output terminal of the second logic control unit is connected to a second power supply pin, wherein the second logic control unit controls the switching of the second switching transistor to convert a first DC voltage into a second DC voltage and outputs it through the second power supply pin; and a second diode, the cathode of which is connected to the second end of the second switching transistor, and the anode of which is connected to a common ground pin.

[0011] According to one embodiment of the present invention, a first inductor is connected between a first power supply pin and a first switch pin, and a second inductor is connected between a second power supply pin and a second switch pin, wherein the first inductor and the second inductor are set independently of the intelligent power module.

[0012] According to one embodiment of the present invention, the inverter circuit includes a first power switching element to a sixth power switching element, the first power switching element to the sixth power switching element constitutes a three-phase bridge arm, and the three-phase bridge arm is connected between the positive terminal of the DC bus and the negative terminal of the DC bus.

[0013] According to one embodiment of the present invention, each phase of the three-phase bridge arm includes an upper bridge and a lower bridge. One end of the upper bridge of each phase bridge arm is connected to the positive terminal of the DC bus, and the other end of the upper bridge of each phase bridge arm is connected to one end of the lower bridge of each phase bridge arm and has a node. The other end of the lower bridge of each phase bridge arm is connected to the negative terminal of the DC bus through a sampling resistor.

[0014] According to one embodiment of the present invention, the nodes of each phase bridge arm are respectively connected to the corresponding high-voltage power supply pins of the high-voltage driver chip through bootstrap capacitors.

[0015] According to one embodiment of the present invention, the sampling resistor and the bootstrap capacitor are surface-mount components.

[0016] To achieve the above objectives, a second aspect of the present invention provides a frequency converter including the aforementioned intelligent power module.

[0017] According to the present invention, the frequency converter, by including the above-described intelligent power module, can effectively simplify the design of the module's peripheral circuit, thereby significantly reducing the size of the electronic control unit, saving space occupied by the electronic control unit, and helping to reduce costs.

[0018] According to one embodiment of the present invention, the frequency converter is an indoor unit of an air conditioner, an outdoor unit of an air conditioner, a refrigerator, or a freezer.

[0019] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0020] Figure 1 This is a structural block diagram of an intelligent power module according to an embodiment of the present invention;

[0021] Figure 2 This is a schematic diagram of the structure of an intelligent power module according to an embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of the structure of a smart power module according to another embodiment of the present invention;

[0023] Figure 4 This is a schematic diagram of the structure of a first switching power supply according to an embodiment of the present invention;

[0024] Figure 5 This is a schematic diagram of the structure of a second switching power supply according to an embodiment of the present invention;

[0025] Figure 6 This is a structural block diagram of a frequency converter according to an embodiment of the present invention. Detailed Implementation

[0026] The embodiments of the present invention are described in detail below with reference to the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout.

[0027] The intelligent power module and frequency converter provided in the embodiments of the present invention are described below with reference to the accompanying drawings.

[0028] Figure 1 This is a structural block diagram of a smart power module according to an embodiment of the present invention, with reference to... Figure 1 As shown, the intelligent power module 100 may include: an integrated first switching power supply 110, a second switching power supply 120, a microcontroller 130, a high-voltage drive chip 140, and an inverter circuit 150.

[0029] Specifically, the first switching power supply 110 converts the DC bus voltage into a first DC voltage to power the high-voltage drive chip 140 and the second switching power supply 120; the second switching power supply 120 converts the first DC voltage into a second DC voltage to power the microcontroller 130; the microcontroller 130 outputs a control signal to the high-voltage drive chip 140 according to the target motor speed; the high-voltage drive chip 140 outputs a drive signal to the inverter circuit 150 according to the control signal to drive the power switching elements in the inverter circuit 150 to turn on or off. Furthermore, the first DC voltage is lower than the DC bus voltage, and the second DC voltage is lower than the first DC voltage.

[0030] Specifically, the Intelligent Power Module 100 (IPM) can be used in variable frequency drive (VFD) systems to convert AC mains power into electrical energy at the required frequency, thereby achieving stepless speed regulation of the motor. An IPM is a modularly packaged circuit component capable of withstanding high voltage and high current, and is a core component of VFD systems. In this application, the IPM integrates a first switching power supply 110, a second switching power supply 120, a microcontroller 130, a high-voltage drive chip 140, and an inverter circuit 150.

[0031] The microcontroller 130, abbreviated as MCU (Microcontroller Unit), is a chip-level computer that integrates a central processing unit, memory, counter, input / output interface, etc. on a single chip to perform different combinations of control for different applications. It is also called a single-chip microcomputer or single-chip microcomputer. For example, in this application, the MCU can output control signals to the high-voltage drive chip 140 according to the target speed of the motor.

[0032] The high voltage driver chip 140, abbreviated as HVIC (High Voltage Integrated Circuit), is a driver chip with an integrated gate drive circuit. It is used to output drive signals to the inverter circuit 150 according to the control signal, so as to drive the power switching elements in the inverter circuit 150 to turn on or off. It can have functions such as overcurrent protection, undervoltage protection and overtemperature protection, and needs to withstand high voltage.

[0033] Compared to HVIC, MCU is a low-voltage integrated circuit, while HVIC is a high-voltage integrated circuit. Therefore, different switching power supplies are needed to power MCU and HVIC respectively. For example, in this application, the first switching power supply 110 can convert the higher DC bus voltage into a lower first DC voltage Va (e.g., 15V) to power HVIC. At the same time, the second switching power supply 120 converts the lower first DC voltage Va output by the first switching power supply 110 into an even lower second DC voltage Vb (e.g., 5V or 3.3V) to power MCU.

[0034] When the IPM is working, the first switching power supply 110 supplies power to the HVIC, and the second switching power supply 120 supplies power to the MCU. The MCU has a motor control program burned into it. When controlling the motor, the motor control program outputs a control signal to the HVIC according to the target speed of the motor. The HVIC then outputs a corresponding drive signal to the inverter circuit 150 to drive the power switching elements in the inverter circuit 150 to turn on or off.

[0035] The intelligent power module of this invention, through the high integration of a first switching power supply, a second switching power supply, an MCU, an HVIC, and an inverter circuit, has the following significant advantages: By integrating the switching power supply that powers the HVIC and the power supply that powers the MCU both inside the module, the design of the module's peripheral circuits can be effectively simplified, resulting in a significant reduction in the size of the power control unit, thus saving space and helping to reduce costs; at the same time, since the core components of the power control unit are integrated inside the module and are encapsulated and protected, short circuits between these core components are avoided due to environmental pollutants and insects, improving the overall reliability of the power control unit; furthermore, the high integration reduces the number of components required for the manufacturing and assembly of the power control unit, which is beneficial to improving the production efficiency of the power control unit.

[0036] In one embodiment, reference Figure 2 and Figure 3 As shown, a first switching power supply 110, a second switching power supply 120, an MCU, and an HVIC are integrated to form a smart driver chip 200.

[0037] It should be understood that the four functional units—the first switching power supply 110, the second switching power supply 120, the MCU, and the HVIC—can be integrated onto a single chip, or they can be arranged in any combination or independently on multiple chips. For example, they can be located on four separate chips, or the HVIC and the first switching power supply 110 can be integrated onto one chip, while the MCU and the second switching power supply 120 can be integrated onto another chip, and so on. Preferably, the four functional units—the first switching power supply 110, the second switching power supply 120, the MCU, and the HVIC—are integrated onto a single chip, which can be called the intelligent driver chip 200. This internal integration and packaging further reduces the module size and the number of components installed inside the module, which is beneficial for improving the module's production efficiency and reliability.

[0038] In one embodiment, the first switching power supply 110 and the second switching power supply 120 have the same circuit topology and adopt a BUCK circuit structure.

[0039] In other words, the two switching power supplies can be configured as DC-DC conversion circuits with an output voltage lower than the input voltage to achieve step-down power supply. It can be understood that the first switching power supply 110 and the second switching power supply 120, which have a BUCK circuit structure, are non-isolated switching power supplies. Compared with isolated switching power supplies in related technologies, they do not require a large isolation transformer; only a smaller inductor is needed, thus further reducing the size of the electronic control unit and effectively saving space.

[0040] It should be noted that IPM can be applied to variable frequency home appliances, specifically to the drive of indoor fans in air conditioners, the drive of outdoor fans in air conditioners, and the drive of compressors in refrigerators. It is important to note that, considering application safety and signal stability, some low-voltage functional modules in variable frequency home appliances are not suitable for the aforementioned non-isolated switching power supply. For example, if a remote control receiver or WiFi (Wireless Fidelity) module needs to be installed on the indoor unit panel of a variable frequency home air conditioner, then these low-voltage modules cannot be directly powered by the switching power supply of the intelligent power module described in this application; instead, an isolated switching power supply is required to power these low-voltage functional modules.

[0041] Optionally, Figure 4 This is a schematic diagram of the structure of a first switching power supply for an intelligent power module according to an embodiment of the present invention. (Refer to...) Figure 4As shown, the first switching power supply 110 may include: a first switching transistor 111, a first logic control unit 112, and a first diode 113. The first terminal of the first switching transistor 111 is connected to the positive terminal P of the DC bus, and the second terminal of the first switching transistor 111 is connected to the first switching pin SW1. The first logic control unit 112 is connected to the control terminal of the first switching transistor 111, the positive terminal P of the DC bus, and the second terminal of the first switching transistor 111, and the output terminal of the first logic control unit 112 is connected to the first power supply pin VCC. The cathode of the first diode 113 is connected to the second terminal of the first switching transistor 111, and the anode of the first diode 113 is connected to the common ground pin VSS.

[0042] Specifically, refer to Figures 2-4 As shown, the input terminal of the first switching power supply 110 is electrically connected to the DC bus, where the positive terminal of the DC bus can be represented as P and the negative terminal of the DC bus can be represented as N. The first switching power supply 110 can step down the DC bus voltage to a first DC voltage Va, where the DC bus voltage can be a high voltage of 380V. The first DC voltage Va is used to supply power to the HVIC and the second switching power supply 120. The first DC voltage Va can be a low voltage of 15V to meet the power supply requirements of the HVIC.

[0043] refer to Figure 4 As shown, in the first switching power supply 110, the first switching transistor 111 can be a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor). Its drain D is electrically connected to the positive terminal P of the DC bus, its source S is electrically connected to the first switching pin SW1, and its gate G is electrically connected to the first logic control unit 112. The first logic control unit 112 can include four terminals: the first terminal is electrically connected to the control terminal (gate G) of the first switching transistor 111; the second terminal is electrically connected to the positive terminal P of the DC bus; the third terminal is electrically connected to the source S of the first switching transistor 111; and the fourth terminal, the output terminal of the first logic control unit 112, is electrically connected to the first power supply pin VCC. The first logic control unit 112 controls the switching of the first switching transistor 111 to convert the DC bus voltage into a first DC voltage Va, which is then output through the first power supply pin VCC.

[0044] Further, refer to Figure 2 As shown, a first inductor L1 is also connected between the first power supply pin VCC and the first switch pin SW1. This first inductor L1 is set independently of the IPM. (Reference) Figure 4As shown, the first diode 113 in the first switching power supply 110 is a freewheeling diode. Its cathode is electrically connected to the source S of the first switching transistor 111, and its anode is electrically connected to the common ground pin VSS (it should be noted that this common ground pin VSS is also connected to the negative terminal N of the DC bus), used to prevent the induced electromotive force in the first inductor L1 from damaging the circuit components. It can be understood that since the first switching power supply 110 is set as a non-isolated switching power supply, it only needs to be equipped with a small inductor and does not need to be equipped with a large isolation transformer, which can further reduce the size of the electronic control and thus effectively save the space occupied by the electronic control.

[0045] Alternatively, Figure 5 This is a schematic diagram of the structure of a second switching power supply for an intelligent power module according to an embodiment of the present invention. (Refer to...) Figure 5 As shown, the second switching power supply 120 includes: a second switching transistor 121, a second logic control unit 122, and a second diode 123. The first terminal of the second switching transistor 121 is connected to the output terminal of the first logic control unit 112, and the second terminal of the second switching transistor 121 is connected to the second switching pin SW2. The second logic control unit 122 is connected to the control terminal of the second switching transistor 121, the output terminal of the first logic control unit 112, and the second terminal of the second switching transistor 121, respectively. The output terminal of the second logic control unit 122 is connected to the second power supply pin VDD. The cathode of the second diode 123 is connected to the second terminal of the second switching transistor 121, and the anode of the second diode 123 is connected to the common ground pin VSS.

[0046] Specifically, refer to Figure 2-3 as well as Figure 5 As shown, the input terminal of the second switching power supply 120 is connected to the output terminal of the first switching power supply 110, and the output terminal of the second switching power supply 120 is connected to the power supply terminal of the MCU. The second switching power supply 120 is used to step down the first DC voltage Va output by the first switching power supply 110 to a second DC voltage Vb to power the MCU. The second DC voltage Vb can be a low voltage of 5V or 3.3V to meet the power supply requirements of the MCU.

[0047] refer to Figure 5As shown, in the second switching power supply 120, the second switching transistor 121 can be a MOSFET. Its drain D is connected to the output terminal (fourth terminal) of the first logic control unit 112, its source S is connected to the second switching pin SW2, and its gate G is connected to the second logic control unit 122. The second logic control unit 122 includes four terminals: the first terminal is connected to the control terminal (gate G) of the second switching transistor 121, the second terminal is connected to the output terminal of the first logic control unit 112, the third terminal is connected to the source S of the second switching transistor 121, and the fourth terminal, i.e., its output terminal, is connected to the second power supply pin VDD. This enables the second logic control unit 122 to control the second switching transistor 121, converting the first DC voltage Va output by the first switching power supply 110 into a second DC voltage Vb, which is then output through the second power supply pin VDD.

[0048] Further, refer to Figure 2 As shown, a second inductor L2 is also connected between the second switch pin SW2 and the second power supply pin VDD. This second inductor L2 is set independently of the IPM. (Reference) Figure 5 As shown, the second diode 123 in the second switching power supply 120 is a freewheeling diode. Its cathode is electrically connected to the source S of the second switching transistor 121, and its anode is electrically connected to the common ground pin VSS. This is used to prevent the induced electromotive force in the second inductor L2 from damaging the circuit components. It can be understood that since the second switching power supply 120 is set as a non-isolated switching power supply, it only needs to be paired with a smaller inductor, eliminating the need for a larger isolation transformer. This allows for further reduction in the size of the electronic control unit, effectively saving space.

[0049] In some embodiments, reference Figure 2 As shown, the inverter circuit 150 may include a first power switching element to a sixth power switching element, which constitutes a three-phase bridge arm connected between the positive terminal P of the DC bus and the negative terminal N of the DC bus.

[0050] In other words, the inverter circuit 150 can be a three-phase bridge inverter circuit located between the positive and negative terminals of the DC bus. However, it should be understood that the inverter circuit can be not only the aforementioned three-phase bridge inverter circuit, but also a half-bridge inverter circuit, a full-bridge inverter circuit, etc., and this application does not impose any specific restrictions on it.

[0051] Furthermore, each phase arm in the three-phase bridge consists of an upper bridge and a lower bridge. For each phase arm, one end of the upper bridge is electrically connected to the positive terminal P of the DC bus, and the other end of the upper bridge is electrically connected to one end of the lower bridge of the corresponding arm, forming a node. The other end of the lower bridge of each arm is electrically connected to the negative terminal N of the DC bus through a sampling resistor Rs. Optionally, the sampling resistor Rs is a surface-mount element.

[0052] As a concrete example, see reference Figures 2-3As shown, the inverter circuit 150 is a three-phase bridge inverter circuit, which includes six power switching elements, namely the first power switching element to the sixth power switching element (referred to as T1, T2, T3, T4, T5, and T6 in sequence). These power switching elements are semiconductor devices that can controllably turn the circuit on or off. They need to withstand high voltage and high current, and can be IGBTs, MOSFETs, etc. Specifically, the emitter of the first power switching element T1 is electrically connected to the collector of the fourth power switching element T4 to form a first bridge arm, with the first power switching element T1 serving as the upper bridge of the first bridge arm and the fourth power switching element T4 serving as the lower bridge of the first bridge arm; the emitter of the second power switching element T2 is electrically connected to the collector of the fifth power switching element T5 to form a second bridge arm, with the second power switching element T2 serving as the upper bridge of the second bridge arm and the fifth power switching element T5 serving as the lower bridge of the second bridge arm; the emitter of the third power switching element T3 is electrically connected to the collector of the sixth power switching element T6 to form a third bridge arm, with the third power switching element T3 serving as the upper bridge of the third bridge arm and the sixth power switching element T6 serving as the lower bridge of the third bridge arm. Furthermore, one end of the upper bridge of each phase bridge arm is electrically connected to the positive terminal P of the DC bus, and one end of the lower bridge of each phase bridge arm is electrically connected to the negative terminal N of the DC bus. The node between the upper and lower bridges of the first bridge arm is electrically connected to the U-phase port U of the three-phase bridge inverter circuit, the node between the upper and lower bridges of the second bridge arm is electrically connected to the V-phase port V of the three-phase bridge inverter circuit, and the node between the upper and lower bridges of the third bridge arm is electrically connected to the W-phase port W of the three-phase bridge inverter circuit. In this way, the nodes between the upper and lower bridges of the three-phase bridge arm are respectively connected to the leads of the three-phase windings of the motor.

[0053] In this example, continue to refer to Figure 2 and Figure 3As shown, for an MCU, its input terminals may include a data transmission port TXD (Transmit Data), a data reception port RXD (Receive Data), a serial wire debug clock port SWCLK (Serial Wire Debug Clock), a serial wire debug data port SWDIO (Serial Wire Debug Data I / O), a display port LED (Light-emitting Diode), a speed control port SPEED, and sampling ports OPN and OPP. During operation, relevant data is input to the MCU through the corresponding input terminals. The MCU, through the corresponding control program, outputs UH, VH, WH, UL, VL, and WL control signals to the HVIC. For example, when controlling a motor, the MCU has a motor control program programmed inside. When the target motor speed is input through the speed control port SPEED, the MCU can output a control signal to the HVIC according to the target motor speed. The HVIC then outputs a corresponding drive signal to the inverter circuit 150 to drive the power switching elements to turn on or off. During this process, the MCU also collects the voltage across the sampling resistor Rs through the sampling ports OPN and OPP, calculates the operating current of the inverter circuit 150 based on this voltage, and generates a control signal for the HVIC based on the operating current of the inverter circuit 150 and the target motor speed. Specifically, the voltage across the sampling resistor Rs can be collected through a sampling circuit consisting of resistors R1 and R2 and capacitor Cs. In this circuit, resistor R1 is connected between the MCU's sampling port OPN and one end of the sampling resistor Rs, resistor R2 is connected between the MCU's sampling port OPP and the other end of the sampling resistor Rs, and capacitor Cs is connected in parallel with the sampling resistor Rs. Furthermore, refer to... Figure 2 As shown, the MCU may also include an enable port FO, which is connected to the second power supply pin VDD via a pull-up resistor. The operation of the HVIC can be controlled through the enable port FO.

[0054] For HVIC, refer to Figure 2 and Figure 3As shown, the UH input signal of the HVIC controls the voltage of the first gate drive output port HO1, which is electrically connected to the gate of the first power switching element T1 through the HO1 port to control the switching state of the U-phase upper bridge; the VH input signal of the HVIC controls the voltage of the second gate drive output port HO2, which is electrically connected to the gate of the second power switching element T2 through the HO2 port to control the switching state of the V-phase upper bridge; the WH input signal of the HVIC controls the voltage of the third gate drive output port HO3, which is electrically connected to the gate of the third power switching element T3 through the HO3 port to control the switching state of the W-phase upper bridge; HVIC The UL input signal of the HVIC controls the voltage of the fourth gate drive output port LO1, which is electrically connected to the gate of the fourth power switching element T4 through the LO1 port to control the switching state of the U-phase lower bridge; the VL input signal of the HVIC controls the voltage of the fifth gate drive output port LO2, which is electrically connected to the gate of the fifth power switching element T5 through the LO2 port to control the switching state of the V-phase lower bridge; the WL input signal of the HVIC controls the voltage of the sixth gate drive output port LO3, which is electrically connected to the gate of the sixth power switching element T6 through the LO3 port to control the switching state of the sixth power switching element T6 of the W-phase lower bridge.

[0055] For inverter circuit 150, refer to Figure 2As shown, six power switching elements T1, T2, T3, T4, T5, and T6 are connected in anti-parallel to six freewheeling diodes D1, D2, D3, D4, D5, and D6, respectively. Specifically, the cathode of the first freewheeling diode D1 is electrically connected to the collector of the first power switching element T1, the cathode of the second freewheeling diode D2 is electrically connected to the collector of the second power switching element T2, and the cathode of the third freewheeling diode D3 is electrically connected to the collector of the third power switching element T3. The collectors of the first power switching element T1, the second power switching element T2, and the third power switching element T3 are electrically connected to the positive terminal P of the DC bus. Correspondingly, the anode of the fourth freewheeling diode D4 is electrically connected to the emitter of the fourth power switching element T4, the anode of the fifth freewheeling diode D5 is electrically connected to the emitter of the fifth power switching element T5, and the anode of the sixth freewheeling diode D6 is electrically connected to the emitter of the sixth power switching element T6. The emitters of the fourth power switching element T4, the fifth power switching element T5, and the sixth power switching element T6 are connected in series with the sampling resistor Rs and then electrically connected to the negative terminal N of the DC bus. Simultaneously, the emitter of the first power switching element T1, the anode of the first freewheeling diode D1, the collector of the fourth power switching element T4, and the cathode of the fourth freewheeling diode D4 are electrically connected to the U-phase output port U of the IPM (i.e., the U-phase port U of the inverter circuit 150); correspondingly, the emitter of the second power switching element T2, the anode of the second freewheeling diode D2, the collector of the fifth power switching element T5, and the cathode of the fifth freewheeling diode D5 are electrically connected to the V-phase output port V of the IPM (i.e., the V-phase port V of the inverter circuit 150); correspondingly, the emitter of the third power switching element T3, the anode of the third freewheeling diode D3, the collector of the sixth power switching element T6, and the cathode of the sixth freewheeling diode D6 are electrically connected to the W-phase output port W of the IPM (i.e., the W-phase port W of the inverter circuit 150). Meanwhile, the gate of the first power switch element T1 is connected to the HO1 port, the gate of the second power switch element T2 is connected to the HO2 port, the gate of the third power switch element T3 is connected to the HO3 port, the gate of the fourth power switch element T4 is connected to the LO1 port, the gate of the fifth power switch element T5 is connected to the LO2 port, and the gate of the sixth power switch element T6 is connected to the LO3 port.

[0056] During the operation of the inverter circuit, the MCU has a motor control program programmed into it. Based on the target motor speed input at the speed control port SPEED, it outputs control signals UL, VL, WL, UH, VH, WH to HVIC. HVIC then generates the gate drive voltage required to drive the power switching elements T1, T2, T3, T4, T5, and T6 of the inverter circuit based on the control signals UH, VH, WH, UL, VL, and WL.

[0057] Optionally, the upper and lower bridge nodes of each phase arm are connected to the corresponding high-voltage power supply pin of the HVIC via corresponding bootstrap capacitors. Specifically, refer to... Figure 2 and Figure 3 As shown, the inverter circuit 150 may include three bootstrap capacitors (denoted as C1, C2, and C3, respectively). Correspondingly, the HVIC includes a first upper-bridge bootstrap reference pin VS1, a second upper-bridge bootstrap reference pin VS2, a third upper-bridge bootstrap reference pin VS3, a first high-voltage power supply pin VB1, a second high-voltage power supply pin VB2, and a third high-voltage power supply pin VB3. Specifically, the first bootstrap capacitor C1 is electrically connected between pins VS1 and VB1, and pin VS1 is connected to the upper and lower bridge nodes of the first bridge arm of the inverter circuit 150; the second bootstrap capacitor C2 is electrically connected between pins VS2 and VB2, and pin VS2 is connected to the upper and lower bridge nodes of the second bridge arm of the inverter circuit 150; the third bootstrap capacitor C3 is electrically connected between pins VS3 and VB3, and pin VS3 is connected to the upper and lower bridge nodes of the third bridge arm of the inverter circuit 150. Optionally, the above three bootstrap capacitors may be surface-mount components.

[0058] In summary, the intelligent power module according to embodiments of the present invention converts the DC bus voltage into a first DC voltage via a first switching power supply to power the HVIC and a second switching power supply, and converts the first DC voltage into a second DC voltage via the second switching power supply to power the MCU. The MCU outputs a control signal to the HVIC based on the target motor speed, and the HVIC outputs a drive signal to the inverter circuit based on the control signal to drive the power switching elements in the inverter circuit to turn on or off. This effectively simplifies the design of the module's peripheral circuitry, significantly reduces the size of the electronic control unit, saves space, and helps reduce costs.

[0059] Figure 6 This is a structural block diagram of a frequency converter according to an embodiment of the present invention. (Refer to...) Figure 6 As shown, the inverter device 1000 includes the aforementioned intelligent power module 100, which can specifically be a refrigerator, freezer, indoor unit or outdoor unit of an air conditioner, etc.

[0060] According to the present invention, the frequency converter, by including the above-described intelligent power module, can effectively simplify the design of the module's peripheral circuit, thereby significantly reducing the size of the electronic control unit, saving space occupied by the electronic control unit, and helping to reduce costs.

[0061] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0062] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0063] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A smart power module, characterized in that, The device includes an integrated first switching power supply, a second switching power supply, a microcontroller, a high-voltage drive chip, and an inverter circuit. The first switching power supply converts the DC bus voltage into a first DC voltage to power the second switching power supply and the high-voltage drive chip. The second switching power supply converts the first DC voltage into a second DC voltage to power the microcontroller. The microcontroller outputs a control signal to the high-voltage drive chip based on the target motor speed. The high-voltage drive chip outputs a drive signal to the inverter circuit based on the control signal to drive the power switching elements in the inverter circuit to turn on or off. The first DC voltage is less than the DC bus voltage, and the second DC voltage is less than the first DC voltage.

2. The intelligent power module according to claim 1, characterized in that, The first switching power supply, the second switching power supply, the microcontroller, and the high-voltage drive chip are integrated together to form an intelligent drive chip.

3. The intelligent power module according to claim 1, characterized in that, The first switching power supply and the second switching power supply have the same circuit topology and adopt a BUCK circuit structure.

4. The intelligent power module according to claim 3, characterized in that, The first switching power supply includes: The first switch transistor has its first end connected to the positive terminal of the DC bus and its second end connected to the first switch transistor pin. The first logic control unit is connected to the control terminal of the first switch, the positive terminal of the DC bus, and the second terminal of the first switch. The output terminal of the first logic control unit is connected to the first power supply pin. The first logic control unit controls the switching of the first switch to convert the DC bus voltage into the first DC voltage and outputs it through the first power supply pin. The first diode has its cathode connected to the second terminal of the first switching transistor, and its anode connected to the common ground pin.

5. The intelligent power module according to claim 4, characterized in that, The second switching power supply includes: The second switch has its first end connected to the output terminal of the first logic control unit and its second end connected to the second switch pin. The second logic control unit is connected to the control terminal of the second switch, the output terminal of the first logic control unit, and the second terminal of the second switch. The output terminal of the second logic control unit is connected to the second power supply pin. The second logic control unit controls the switching of the second switch to convert the first DC voltage into the second DC voltage and outputs it through the second power supply pin. The second diode has its cathode connected to the second terminal of the second switching transistor, and its anode connected to the common ground pin.

6. The intelligent power module according to claim 5, characterized in that, A first inductor is connected between the first power supply pin and the first switch pin, and a second inductor is connected between the second power supply pin and the second switch pin. The first inductor and the second inductor are set independently of the intelligent power module.

7. The intelligent power module according to any one of claims 1-6, characterized in that, The inverter circuit includes a first power switching element to a sixth power switching element, which together form a three-phase bridge arm connected between the positive terminal of the DC bus and the negative terminal of the DC bus.

8. The intelligent power module according to claim 7, characterized in that, Each phase of the three-phase bridge arm includes an upper bridge and a lower bridge. One end of the upper bridge of each phase bridge arm is connected to the positive terminal of the DC bus. The other end of the upper bridge of each phase bridge arm is connected to one end of the lower bridge of each phase bridge arm and has a node. The other end of the lower bridge of each phase bridge arm is connected to the negative terminal of the DC bus through a sampling resistor.

9. The intelligent power module according to claim 8, characterized in that, Each node of the phase bridge arm is connected to the corresponding high-voltage power supply pin of the high-voltage driver chip via a bootstrap capacitor.

10. The intelligent power module according to claim 9, characterized in that, The sampling resistor and the bootstrap capacitor are surface-mount components.

11. A frequency converter, characterized in that, Includes the intelligent power module according to any one of claims 1-10.

12. The frequency converter according to claim 11, characterized in that, The frequency conversion equipment is an indoor unit of an air conditioner, an outdoor unit of an air conditioner, a refrigerator, or a freezer.

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