Power module, power assembly and electric vehicle

Abstract

This application relates to the field of power electronics technology, and more particularly to a power module, powertrain, and electric vehicle. The power module includes a substrate, a first input terminal, a second input terminal, an output terminal, a first switching device, a second switching device, and two connecting portions. The substrate is used to connect with multiple first and second switching devices to form a bridge arm circuit. The power module includes two breaks: one break for blocking the circuit connection between the first input terminal and the output terminal, and the other break for blocking the circuit connection between the second input terminal and the output terminal. The circuits on both sides of each break are connected through a connecting portion. The melting point of each connecting portion is lower than the melting point of the metal layer of the substrate. This power module can achieve bridge arm shoot-through short-circuit suppression function, improving the module's safety.

Description

Technical Field

[0001] This application relates to the field of power electronics technology, and more particularly to a power module, powertrain, and electric vehicle. Background Technology

[0002] Power electronic converter systems composed of power modules can convert energy through power conversion circuits. Circuit topologies composed of bridge arms, such as half-bridge circuits and full-bridge circuits, are widely used in power conversion circuits.

[0003] If the upper and lower tubes that make up the bridge arm are connected, it will cause a short circuit in the entire bridge arm, which will generate a large current, causing damage to the switching tube or even an explosion. Summary of the Invention

[0004] This application provides a power module, powertrain, and electric vehicle. The power module can realize the function of bridge arm shoot-through short circuit suppression, and can also suppress bridge arm shoot-through short circuit between parallel modules, thereby improving the safety of the module.

[0005] In a first aspect, this application provides a power module, which includes a substrate, a first input terminal, a second input terminal, an output terminal, a first switching device, a second switching device, and two connecting portions. The first and second switching devices are connected to form a bridge arm circuit, with the two ends of the bridge arm circuit connected to the first and second input terminals respectively. The midpoint of the bridge arm circuit is connected to the output terminal. The first switching device is connected between the first input terminal and the midpoint of the bridge arm, and the second switching device is connected between the second input terminal and the midpoint of the bridge arm. The first and second switching devices are disposed on the substrate. The power module has two breaks, one of which is used to block the circuit connection between the first input terminal and the output terminal, and the other break is used to block the circuit connection between the second input terminal and the output terminal. The circuits on both sides of each break are connected by a connecting portion, and the melting point of the connecting portion is lower than the melting point of the metal layer of the substrate.

[0006] The aforementioned power module forms a short-circuit suppression structure connected in series in the circuit through the break and connection. When a shoot-through occurs between the upper and lower bridge arms in the bridge arm circuit with the upper arm on and the lower arm off, the connection between the first input terminal and the output terminal is used to suppress circuit conduction. When a shoot-through occurs between the upper and lower bridge arms in the bridge arm circuit formed by this power module with the lower arm on and the upper arm off, the connection between the second input terminal and the output terminal is used to suppress circuit conduction. These two sets of short-circuit suppression structures can effectively suppress shoot-through in the upper and lower bridge arm circuits, preventing damage to electrical components and module failure caused by short circuits in the shoot-through fault mode. When applied to a circuit with multiple power modules connected in parallel, the short-circuit suppression structure can also suppress a shoot-through short circuit between the upper arm of one module and the lower arm of another module.

[0007] In one embodiment, each connector is configured to either melt or increase impedance when a reference value reaches a set threshold. The reference value includes at least one of the current flowing through the connector or the heat generated by the connector when the bridge arm circuit is shoot-through. When a shoot-through occurs between the upper and lower bridge arms, the current in the bridge arm circuit increases, and the connector generates more heat. At this time, the connector melts to break the circuit or increases the impedance to extend the short-circuit protection time, thus achieving a short-circuit suppression effect.

[0008] One break point is located between the first switching device and the first input terminal or between the first switching device and the output terminal, and the other break point is located between the second switching device and the second input terminal or between the second switching device and the output terminal. The positions of the break points and their corresponding switching devices in the upper or lower bridge arm are flexibly adjustable.

[0009] In one embodiment, at least one of the two breaks is disposed on the substrate. The break is formed by the structural design of the substrate, which makes it easier to arrange the first switching device and the second switching device and connect the wiring.

[0010] In one embodiment, the substrate includes an insulating base plate and a metal layer disposed on the insulating base plate. A first input terminal, a second input terminal, an output terminal, a first switching device, and a second switching device are disposed on the metal layer. One break is located in the metal layer between the first input terminal and the first switching device, or between the first switching device and the output terminal; the other break is located in the metal layer between the second input terminal and the second switching device, or between the second switching device and the output terminal. The metal layer can be directly formed with breaks during the process of being disposed on the insulating base plate. Forming breaks through the structural design of the metal layer simplifies the process.

[0011] In one embodiment, the metal layer includes a first sub-metal layer, a second sub-metal layer, a third sub-metal layer, a fourth sub-metal layer, and a fifth sub-metal layer that are isolated from each other. A first switching device is disposed on the first sub-metal layer and connected to the second sub-metal layer, a second switching device is disposed on the second sub-metal layer and connected to the third sub-metal layer, and an output terminal is disposed on the fourth sub-metal layer. A first input terminal is disposed on the fifth sub-metal layer, with one break located between the fourth and second sub-metal layers and another break located between the fifth and first sub-metal layers; or, a second input terminal is disposed on the fifth sub-metal layer, with one break located between the fourth and second sub-metal layers and another break located between the fifth and third sub-metal layers. The different sub-metal layers of the metal layer meet the connection requirements of the bridge arm circuit, and it is easier to design the position of the break relative to the circuit through the isolation between the different sub-metal layers.

[0012] In one embodiment, the metal layer includes a first sub-metal layer, a second sub-metal layer, a third sub-metal layer, a fourth sub-metal layer, and a fifth sub-metal layer that are phase-isolated. A first switching device is disposed on the first sub-metal layer and connected to the second sub-metal layer, a second switching device is disposed on the second sub-metal layer and connected to the third sub-metal layer, a first input terminal is disposed on the fourth sub-metal layer, and a second input terminal is disposed on the fifth sub-metal layer. One break point is located between the fourth sub-metal layer and the first sub-metal layer, and another break point is located between the fifth sub-metal layer and the third sub-metal layer. By disposing of the two short-circuit suppression structures on the input side of the upper and lower bridge arms, the short-circuit suppression function can be achieved more quickly when the upper and lower bridge arms are connected.

[0013] In one embodiment, the power module includes an input terminal and an output terminal opposite each other along a first direction. A first input terminal and a second input terminal are arranged adjacently along a second direction at the input terminal, and an output terminal is disposed at the output terminal. Both the first and second directions are perpendicular to the thickness direction of the substrate, with the first direction perpendicular to the second direction. A first sub-metal layer and a second sub-metal layer are arranged at intervals along the second direction, and at least a portion of a third sub-metal layer is arranged at intervals along the second direction on the side of the second sub-metal layer away from the first sub-metal layer. When setting the two breaks, the positions of the different sub-metal layers can be adjusted to reduce the space occupied by the metal layers when setting the breaks, thereby optimizing the layout space.

[0014] In one embodiment, at least one connecting part is a conductive block, which is housed within the fracture surface. The conductive block is in contact with the metal layers on both sides of the fracture surface, and this surface contact ensures a good electrical connection. The conductive block provides a reliable and high-strength connection.

[0015] In one embodiment, the surface of the conductive block facing the insulating base plate is in contact with the insulating base plate, while the surface of the conductive block facing away from the insulating base plate is flush with the surface of the metal layer facing away from the insulating base plate. During normal operation of the power module, the thickness of the connection portion and the thickness of the metal layer remain relatively consistent, which helps maintain the stability and reliability of electrical signal transmission and also facilitates heat dissipation.

[0016] In one embodiment, at least one connection portion includes multiple bonding wires, with each bonding wire's two ends connected to metal layers on both sides of the fracture. The bonding wire connection method is more flexible and less expensive.

[0017] In one embodiment, at least one connecting part is a conductive strip, with both ends of the conductive strip overlapping the metal layers on both sides of the break, facing away from the surface of the insulating base plate. The conductive strip design is easy to maintain and replace, while also maintaining good conductivity and mechanical strength.

[0018] In one embodiment, at least one connection is made of a temperature-sensitive material. When the upper and lower bridge arms are in direct contact, if the current or energy passing through the connection reaches a threshold, the connection can rapidly change its impedance characteristics to suppress current surge, thus giving the controller of the power conversion device more time to implement short-circuit protection.

[0019] Secondly, this application provides a powertrain including a controller and a motor. The controller includes multiple power modules as described in the first aspect above. Each power module has a first input terminal and a second input terminal for connecting to the positive and negative terminals of a power source, respectively, and an output terminal for connecting to one phase of the motor circuit. The powertrain including the aforementioned power modules offers enhanced safety.

[0020] Thirdly, this application provides an electric vehicle, which includes a power source, wheels, and a powertrain as provided in the second aspect. The powertrain's power conversion device receives direct current (DC) from the power source and converts it into alternating current (AC) for output to a motor, which is driven by the wheels. Electric vehicles including the aforementioned power module offer higher safety and performance.

[0021] The technical effects that can be achieved by the second and third aspects mentioned above can be referred to the corresponding effect descriptions in the first aspect mentioned above, and will not be repeated here. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of an electric vehicle provided in an embodiment of this application;

[0023] Figure 2 This is a schematic diagram illustrating the working principle of the powertrain of the electric vehicle provided in the embodiments of this application;

[0024] Figure 3a This is a schematic diagram of the power conversion circuit provided in an embodiment of this application;

[0025] Figure 3b This is a schematic diagram of the structure of one phase bridge arm in the power conversion circuit provided in the embodiment of this application.

[0026] Figure 4a This is a schematic diagram of the structure of one phase bridge arm in the power conversion circuit provided in the embodiment of this application.

[0027] Figure 4b This is a schematic diagram of the structure of one phase bridge arm in the power conversion circuit provided in the embodiment of this application.

[0028] Figure 4c This is a schematic diagram of the structure of one phase bridge arm in the power conversion circuit provided in the embodiment of this application.

[0029] Figure 4d This is a schematic diagram of the structure of one phase bridge arm in the power conversion circuit provided in the embodiment of this application.

[0030] Figure 5 This is a schematic diagram of the power module provided in an embodiment of this application;

[0031] Figure 6a This is a schematic diagram of the power module provided in an embodiment of this application;

[0032] Figure 6b This is a schematic diagram of the power module provided in an embodiment of this application;

[0033] Figure 6c This is a schematic diagram of the power module provided in an embodiment of this application;

[0034] Figure 7a A schematic diagram of a bridge arm circuit formed by the power module provided in an embodiment of this application;

[0035] Figure 7b A schematic diagram of a bridge arm circuit formed by the power module provided in an embodiment of this application;

[0036] Figure 8a This is a schematic diagram of the power module provided in an embodiment of this application;

[0037] Figure 8b This is a cross-sectional structural diagram of the power module provided in an embodiment of this application;

[0038] Figure 9a This is a schematic diagram of the power module provided in an embodiment of this application;

[0039] Figure 9b This is a cross-sectional structural diagram of the power module provided in an embodiment of this application;

[0040] Figure 10a This is a schematic diagram of the power module provided in an embodiment of this application;

[0041] Figure 10b This is a cross-sectional structural diagram of the power module provided in an embodiment of this application;

[0042] Figure 11 This is a schematic diagram of the power module provided in an embodiment of this application.

[0043] Figure label:

[0044] 1000 - Powertrain; 2000 - Vehicle body; 3000 - Wheels; 4000 - Power battery;

[0045] 100 - Motor controller; 200 - Motor;

[0046] 10 - Power conversion circuit; 20 - Drive circuit; 30 - Controller;

[0047] 1-Power module; 11-Substrate; 111-Insulating base plate; 112-Metal layer; 1121-First sub-metal layer; 1122-Second sub-metal layer; 1123-Third sub-metal layer; 1124-Fourth sub-metal layer; 1125-Fifth sub-metal layer; 121-First input terminal; 122-Second input terminal; 13-Output terminal; 14-Power switching device; 141-First switching device; 142-Second switching device; 15-Connecting part; 16-Adapter; 17-Package body;

[0048] D - Break; M - Midpoint of bridge arm; Q - Power switching assembly; V - Short-circuit suppression structure. Detailed Implementation

[0049] In power electronic systems, power conversion circuits typically consist of an upper and lower bridge arm structure. The two ends of this bridge arm structure are connected to the positive and negative terminals of a power supply, converting the direct current (DC) to alternating current (AC) output. In practical applications, the upper and lower bridge arms of this structure are connected in series, posing a risk of shoot-through short circuits, leading to module failure. Current methods to prevent shoot-through may fail if not implemented promptly, potentially damaging switching devices. Furthermore, the failure of the power module could spread to other components. For example, in electric vehicles, to prevent shoot-through in the power conversion circuit, a fuse is connected in series in the main circuit. The fuse's melting threshold energy is more than ten times the energy required for a power module shoot-through failure. If shoot-through occurs, it will first cause a short circuit in the power module, then the fuse will burn out, resulting in a loss of vehicle power and potentially causing a safety accident.

[0050] Based on this, the embodiments of this application provide a power module, powertrain, and electric vehicle. The short-circuit suppression structure can effectively suppress the shoot-through of the upper and lower bridge arm circuits, preventing damage to electrical components and module failure caused by short circuits in the upper and lower bridge arm shoot-through fault mode.

[0051] To make the objectives, technical solutions, and advantages of this application clearer, the application will now be described in further detail with reference to the accompanying drawings.

[0052] The terminology used in the following embodiments is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. As used in the specification and appended claims of this application, the singular expressions “a,” “an,” “the,” “the,” “the,” and “this” are intended to also include expressions such as “one or more” unless the context clearly indicates otherwise.

[0053] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0054] Figure 1 This is a schematic diagram of the structure of an electric vehicle provided in an embodiment of this application. In this embodiment, the electric vehicle includes a powertrain 1000, a vehicle body 2000, wheels 3000, and a power battery 4000. The powertrain 1000 and the power battery 4000 are fixed to the vehicle body 2000. The power battery 4000 can be referred to as a power battery. The power battery 4000 can receive and store electrical energy, and output the stored electrical energy to the powertrain 1000. The powertrain 1000 can convert the electrical energy into mechanical energy to drive the wheels 3000 to rotate, thus enabling the electric vehicle to move.

[0055] In this embodiment, an electric vehicle refers to a wheeled device driven or towed by a power unit. In one implementation, the electric vehicle 100 includes passenger cars, commercial vehicles, or specialized vehicles such as emergency rescue vehicles, water trucks, sewage suction trucks, cement mixer trucks, crane trucks, and medical vehicles. Exemplarily, the electric vehicle 100 includes electric vehicles (EVs), pure electric vehicles (PEVs / BEVs), hybrid electric vehicles (HEVs), range-extended electric vehicles (REEVs), and plug-in hybrid electric vehicles (PHEVs).

[0056] like Figure 2As shown, the powertrain 1000 includes a motor controller 100 and a motor 200. The motor controller 100 receives DC power from the power battery 4000 and outputs AC power to the motor 200. The motor 200 receives the AC power output from the motor controller 100 and drives the wheels 3000 of the electric vehicle. In one embodiment, the powertrain 100 integrates the motor 200 and the motor controller 100 into a single housing, increasing the integration density of the powertrain 1000, reducing its size and cost, facilitating a lightweight design, and improving power density.

[0057] In this embodiment of the application, the motor controller 100 includes, as follows: Figure 3a The power conversion circuit 10, drive circuit 20 and controller 30 shown are included. The power conversion circuit 10 includes a three-phase bridge arm circuit. The two ends of the bridge arm of each phase bridge arm circuit are used to receive power from the power battery 4000. The midpoint M of the bridge arm of each phase bridge arm circuit is used to output one phase of AC power to the motor 200 to drive the motor 200.

[0058] Please refer to Figure 3b The diagram shows a bridge arm circuit. Each bridge arm circuit includes two series-connected, complementary power switch components Q. One end of each power switch component Q is connected to a power supply, and the other end is connected to the midpoint M of the bridge arm. The two ends of each bridge arm circuit are respectively connected to the positive and negative terminals of the power supply.

[0059] Refer to together Figure 3a and Figure 3b The circuit for each phase bridge arm shown includes an upper bridge arm and a lower bridge arm, with the connection point between the upper and lower bridge arms being the midpoint M. End a1 of the upper bridge arm is connected to the positive input of the power battery 4000, and end a2 of the lower bridge arm is connected to the negative input of the power battery 4000. The midpoint M of the bridge arm is the output terminal of this phase bridge arm circuit, used to supply power to one phase winding of the motor 200. A power switch component Q is connected in series between end a1 of the upper bridge arm and the midpoint M, and this power switch component Q is used to control the on / off state of the upper bridge arm circuit. Similarly, a power switch component Q is connected in series between end a2 of the lower bridge arm and the midpoint M, and this power switch component Q is used to control the on / off state of the lower bridge arm circuit. The drive circuit 20 can output a drive signal to each of the aforementioned power switch components Q via the control signal sent by the controller 30 to control the conduction and cutoff of each power switch device, thereby outputting three-phase AC power to the three-phase windings of the motor 200, enabling the motor 200 to output the required torque and drive the electric vehicle.

[0060] During the output of AC power in each bridge arm circuit, the upper and lower bridge arm circuits alternately conduct and output AC power. Within the same bridge arm circuit, due to the change in potential at the midpoint M of the bridge arm, the operation of one power switch component Q can adversely affect the other power switch component Q. If the power switch components Q in the upper and lower bridge arms malfunction and conduct, a direct current path is formed between the positive and negative terminals of the power supply, resulting in excessive instantaneous current and severe heat generation. This could damage the switching devices or even the entire circuit, and also pose a safety hazard.

[0061] In the power conversion circuit provided in the embodiments of this application, such as Figures 4a to 4d As shown, a short-circuit suppression structure V is provided in the upper arm of the bridge arm circuit, and a short-circuit suppression structure V is provided in the lower arm of the bridge arm circuit. When the upper and lower arms of the bridge arm circuit are mis-connected, either short-circuit suppression structure V can operate to effectively suppress the shoot-through of the upper and lower arm circuits, preventing damage to electrical components and module failure caused by short circuits in the shoot-through fault mode of the upper and lower arms. Specifically, in one embodiment, the short-circuit suppression structure V can be implemented by a combination of a break structure and a connection structure. In the device structure forming the power conversion circuit, the circuit structure used to form the upper arm is provided with a break that blocks the circuit connection and a connection part connecting the circuits on both sides of the break. Correspondingly, the circuit structure used to form the lower arm is provided with a break that blocks the circuit connection and a connection part connecting the circuits on both sides of the break. Each connection part is used to melt or increase the impedance when a reference value reaches a set threshold. Here, the reference value includes at least one of the current passing through the connection part or the heat generated by the connection part when the bridge arm circuit is shoot-through. For each break and the corresponding connection part, the connection part is equivalent to being connected in series in the circuits on both sides of the break.

[0062] In one embodiment, the connection can melt and form an open circuit when the current reaches a threshold or when the heat generated by the connection reaches a set threshold, thereby reducing the possibility of the upper and lower bridge arms of the bridge arm circuit being short-circuited and damaging the power module.

[0063] In one embodiment, the connection part can rapidly change its own impedance characteristics when the current reaches a threshold or when the heat generated by the connection part reaches a set threshold, thereby suppressing current ramp-up and giving the controller 30 of the motor controller 100 sufficient time to implement short-circuit protection action.

[0064] Refer to together Figures 4a to 4bThe bridge arm circuit shown has a short-circuit suppression structure V in the upper arm, positioned between terminal a1 (connected to the positive input of the power supply) and the midpoint M of the bridge arm for AC output. Similarly, the short-circuit suppression structure V in the lower arm is positioned between terminal a2 (connected to the negative input of the power supply) and the midpoint M of the bridge arm for AC output. It can be assumed that each short-circuit suppression structure V is positioned between the input terminal for power supply connection and the output terminal for AC output.

[0065] Specifically, each short-circuit suppression structure V can be disposed on one side of the power switching component Q, that is, the short-circuit suppression structure V can be disposed between the power switching component Q and the input terminal, or it can be disposed between the output terminal of the power switching component Q. Taking the upper bridge arm as an example, the short-circuit suppression structure V can be disposed as follows: Figure 4a and Figure 4c As shown, it is positioned between the power switch assembly Q and the midpoint M of the bridge arm, or it can be positioned as follows: Figure 4b and Figure 4d The short-circuit suppression structure V is positioned between the power switch assembly Q and the terminal a1 used to connect to the positive input of the power supply. Taking the lower bridge arm as an example, the short-circuit suppression structure V can be configured as follows: Figure 4a and Figure 4b The power switch assembly Q shown can also be connected to the terminal a2 used for connecting the negative input of the power supply as follows: Figure 4c and Figure 4d The device shown is positioned between the power switch assembly Q and the terminal a1 used to connect to the positive input of the power supply.

[0066] In some embodiments, if multiple bridge arm circuits are formed Figure 3a In the power conversion circuit, the short-circuit suppression structure V in each bridge arm circuit can also prevent phase-to-phase short-circuit faults. Specifically, if the upper bridge arm of one bridge arm circuit is directly connected to the lower bridge arm of another bridge arm circuit, at least one of the short-circuit suppression structures V in the upper bridge arm and the lower bridge arm can disconnect the circuit or increase the impedance, which can also play a short-circuit suppression function and prevent phase-to-phase bridge arm short-circuit faults.

[0067] In one embodiment, the motor controller 100 includes a plurality of... Figure 5 The power module 1 shown, multiple power modules 1 are used to form Figure 3aThe power conversion circuit shown is an assembly of power electronic devices 1 capable of power conversion. These power electronic devices include insulated-gate bipolar transistors (IGBTs), silicon carbide power transistors, silicon transistors, metal-oxide-semiconductor field-effect transistors (MOSFETs), and diodes. The power electronic devices included in each power module 1 are electrically interconnected to form... Figure 3b The circuit shown is a single-phase bridge arm circuit.

[0068] like Figure 5 As shown, a power module 1 includes a substrate 11, a first input terminal 121, a second input terminal 122, an output terminal 13, and a plurality of power switching devices 14. The plurality of power switching devices 14 are electrically connected to form a bridge arm circuit as shown in 3b. The two ends of the bridge arm circuit are connected to the positive and negative terminals of the power supply through the first input terminal 121 and the second input terminal 122, and the midpoint of the bridge arm circuit outputs AC power through the output terminal 13.

[0069] The substrate 11 supports multiple power switching devices 14, which can be structurally laid out and circuit-connected using the substrate 11. In one embodiment, at least one of the two short-circuit suppression structures V in the bridge arm circuit is disposed on the substrate 11. After forming the short-circuit suppression structure V on the substrate 11, the layout and circuit routing of the multiple power switching devices 14 are cheaper and the process is simpler and easier to implement. The melting point of the connection portion in the short-circuit suppression structure V is lower than the melting point of the metal layer in the substrate 11. When the power module 1 is working normally, the short-circuit suppression structure V in the substrate 11 can achieve a good circuit conduction effect. If an abnormal situation of increased current occurs, the connection portion in the short-circuit suppression structure V can melt before the metal layer in the substrate 11, achieving a circuit breaking effect.

[0070] In one specific structural illustration, the substrate 11 includes an insulating base plate 111 and a metal layer 112 disposed on the insulating base plate 111. A portion of the power switching devices 14 are disposed on the metal layer 112 to form an upper bridge arm, and another portion of the power switching devices 14 are disposed on the metal layer 112 to form a lower bridge arm. Each power switching device 14 can be sintered onto the metal layer 112 of the substrate 11 using a silver bonding process. The power switching devices 14 can be connected to the metal layer 112 via one or more adapters 16. The adapters 16 can be copper busbars, bonding wires, or other conductors. A first input terminal 121, a second input terminal 122, and an output terminal 13 are respectively disposed on the metal layer 112 to realize the input and output of the power conversion circuit through the metal layer 112.

[0071] In one embodiment, the first input terminal 121 and the second input terminal 122 of the power module 1 are disposed on the same side of the power module 1, and the output terminal 13 is disposed on the opposite side of the power module 1. The direction in which the first input terminal 121, the second input terminal 122 and the output terminal 13 are opposite is defined as a first direction, and the arrangement direction of the first input terminal 121 and the second input terminal 122 is defined as a second direction. The first direction is perpendicular to the second direction, and both the first direction and the second direction are perpendicular to the thickness direction of the substrate 11.

[0072] In one embodiment, the power module 1 further includes a package 17, which encapsulates the substrate 11 and a plurality of power switching devices 14. The ends of the first input terminal 121, the second input terminal 122, and the output terminal 13 away from the substrate 11 are exposed outside the package 17, which facilitates the connection of electrical devices.

[0073] like Figure 5 As shown, as a specific example, the plurality of power switching devices 14 include at least one first switching device 141 and at least one second switching device 142. The at least one first switching device 141 can be considered as a power switching device for the upper arm of the bridge arm circuit, used to form the upper arm of the bridge arm circuit. The at least one second switching device 142 can be considered as a power switching device for the lower arm of the bridge arm circuit, used to form the lower arm of the bridge arm circuit. In the following embodiments, the plurality of power switching devices 14 including a plurality of first switching devices 141 and a plurality of second switching devices 142 are described as an example.

[0074] In one embodiment, at least one of the two short-circuit suppression structures V in the bridge arm circuit formed by the power module 1 is disposed in the metal layer 112 of the substrate 11. By breaking the metal layer 112 to form the aforementioned break D, and connecting the metal layers 112 on both sides of each break D through the connecting portion 15, the formation process of the short-circuit suppression structure V is simpler and easier to implement. Specifically, the break D of the upper bridge arm can be located in the metal layer 112 between at least one first switching device 141 and the first input terminal 121, or between at least one first switching device 141 and the output terminal 13; the break D of the lower bridge arm can be located in the metal layer 112 between at least one second switching device 142 and the second input terminal 122, or between at least one second switching device 142 and the output terminal 13. In the fabrication of the substrate 11, the metal layer 112 can be disposed on the insulating substrate 111 by processes such as direct bonding. By designing the structure of the metal layer 112, the break D can be directly formed, simplifying the fabrication process.

[0075] In one embodiment, the metal layer 112 includes a plurality of isolated sub-metal layers. The first input terminal 121 and the second input terminal 122 are respectively used to connect the two sub-metal layers. The output terminal 13 is disposed on one sub-metal layer. Each first switching device 141 is disposed between two sub-metal layers. Each second switching device 142 is disposed between two sub-metal layers. At least one break D is formed between two sub-metal layers. The sub-metal layers on both sides of each break D are connected by a connecting portion 15.

[0076] For example, such as Figure 5 As shown, the plurality of sub-metal layers includes a first sub-metal layer 1121, a second sub-metal layer 1122, and a third sub-metal layer 1123. A first input terminal 121 is disposed on the first sub-metal layer 1121, and the first input terminal 121 is specifically connected to the edge of the first sub-metal layer 1121. A second input terminal 122 is disposed on the third sub-metal layer 1123, and the second input terminal 122 is specifically connected to the edge of the third sub-metal layer 1123. An output terminal 13 is disposed on the second sub-metal layer 1122 for connection, and the output terminal 13 is specifically connected to the edge of the second sub-metal layer 1122. Each first switching device 141 is disposed between the first sub-metal layer 1121 and the second sub-metal layer 1122, and each second switching device 142 is disposed between the second sub-metal layer 1122 and the third sub-metal layer 1123. The first sub-metal layer 1121, the second sub-metal layer 1122, the third sub-metal layer 1123, the plurality of first switching devices 141, and the plurality of second switching devices 142 are electrically connected to form a bridge arm circuit. Among them, the circuit between the first input terminal 121 and the output terminal 13 is the upper bridge arm, and the circuit between the second input terminal 122 and the output terminal 13 is the lower bridge arm.

[0077] This power module 1 is used in Figure 3a In the power conversion circuit of the electric vehicle shown, the first input terminal 121 is connected to the positive terminal of the electric vehicle's power battery 4000. The first input terminal 121 is... Figure 3b The upper bridge arm is used to connect one end a1 of the power battery. The second input terminal 122 is connected to the negative terminal of the power battery 4000 of the electric vehicle. The second input terminal 122 is... Figure 3b One end a2 of the lower bridge arm. Output terminal 13 is connected to the electric vehicle motor 200.

[0078] In order to connect a power module 1 in series with the upper and lower arms of the bridge arm circuit formed by the bridge arm circuit, respectively... Figures 4a to 4d The short-circuit suppression structure V shown in this application provides a method such as... Figure 6aThe power module 1 shown has a structure embedded in its metal layer 112 to implement two short-circuit suppression structures V, preventing direct short circuits between the upper and lower bridge arms. In a scenario where multiple power modules 1 are connected to form multiple parallel bridge arm circuits, if the upper bridge arm of one power module's bridge arm circuit is directly connected to the lower bridge arm of another power module's bridge arm circuit, at least one of the short-circuit suppression structures V in the upper and lower bridge arms can either disconnect the circuit or increase the impedance, thus achieving short-circuit suppression and preventing interphase bridge arm short-circuit faults.

[0079] In some embodiments, the first sub-metal layer 1121 and the second sub-metal layer 1122 are arranged at intervals along a second direction, and at least a portion of the third sub-metal layer 1123 is arranged at intervals along the second direction on the side of the second sub-metal layer 1122 away from the first sub-metal layer 1121. The two breaks D can be adjusted according to the positions of the different sub-metal layers included in the metal layer 112 during installation, in order to reduce the layout space.

[0080] like Figure 6a As shown, the metal layer 112 includes two breaks D. One break D is used to block the circuit connection between the first input terminal 121 and the output terminal 13, and the other break D is used to block the circuit connection between the second input terminal 122 and the output terminal 13. Each break D breaks the metal layer 112, and the metal layers 112 on both sides of each break D are isolated from each other, thereby achieving circuit disconnection. It can be considered that each break D isolates the metal layer 112 into two isolated sub-metal layers. In the power module provided in this application embodiment, the metal layers 112 on both sides of each break D are connected by a connection part 15, and each break D and the corresponding connection part 15 are used to form a short-circuit suppression structure V. Each connection part 15 is used to melt or increase the impedance when the reference value reaches a set threshold. The reference value includes at least one of the current passing through the connection part 15 or the heat generated by the connection part 15.

[0081] Please continue to refer to Figure 6aAs shown, each fracture D divides the metal layer 112, and the two parts of the metal layer 112 separated by each fracture D are two isolated sub-metal layers. In one embodiment, the metal layer 112 includes multiple isolated sub-metal layers, including a first sub-metal layer 1121, a second sub-metal layer 1122, a third sub-metal layer 1123, a fourth sub-metal layer 1124, and a fifth sub-metal layer 1125. An output terminal 13 is disposed on the second sub-metal layer 1122, and the output terminal 13 is specifically connected to the edge of the second sub-metal layer 1122. A first input terminal 121 is disposed on the fourth sub-metal layer 1124, and the first input terminal 121 is specifically connected to the edge of the fourth sub-metal layer 1124. A fracture D is formed between the fourth sub-metal layer 1124 and the first sub-metal layer 1121, and the fourth sub-metal layer 1124 on both sides of the fracture D is connected to the first sub-metal layer 1121 through a connecting portion 15. The first sub-metal layer 1121 is connected to the first input terminal 121 via a connecting portion 15 and the fourth sub-metal layer 1124. The fifth sub-metal layer 1125 is connected to the second input terminal 122. Another break D is formed between the fifth sub-metal layer 1125 and the third sub-metal layer 1123. The fifth sub-metal layer 1125 and the third sub-metal layer 1123 on both sides of this break D are connected via a connecting portion 15. The third sub-metal layer 1123 is connected to the second input terminal 122 via a connecting portion 15 and the fifth sub-metal layer 1125. Each break D and the corresponding connecting portion 15 constitute a short-circuit suppression structure V. The break D between the fourth sub-metal layer 1124 and the first sub-metal layer 1121 and the corresponding connecting portion 15 constitute a short-circuit suppression structure V in the upper bridge arm. The break D between the fifth sub-metal layer 1125 and the third sub-metal layer 1123 and the corresponding connecting portion 15 constitute a short-circuit suppression structure V in the lower bridge arm.

[0082] The fourth sub-metal layer 1124 and the first sub-metal layer 1121 are arranged at intervals along the first direction, and the fifth sub-metal layer 1125 and the third sub-metal layer 1123 are arranged at intervals along the first direction. This arrangement can be adapted to the arrangement of the first input terminal 121 and the second input terminal 122, thereby reducing the space occupied by the break D in the metal layer 112, which in turn optimizes the layout of the power module 1 and helps to reduce the size of the power module 1.

[0083] Figure 6a The bridge arm circuit topology formed by power module 1 shown can be referred to Figure 4b As shown. Combined with Figure 6a and Figure 4bAs shown, one connection portion 15 is disposed between multiple first switching devices 141 and the first input terminal 121, and another connection portion 15 is disposed between multiple second switching devices 142 and the second input terminal 122. When a direct connection occurs between the upper and lower bridge arms in the bridge arm circuit with the upper arm on and the lower arm off, a large current instantaneously flows through the connection portion 15 between the multiple first switching devices 141 and the first input terminal 121. The connection portion 15 melts to break the circuit or increases the impedance to extend the control short-circuit protection time, thereby protecting the power module 1. When a direct connection occurs between the upper and lower bridge arms in the bridge arm circuit with the lower arm on and the upper arm off, a large current instantaneously flows through the connection portion 15 between the multiple second switching devices 142 and the second input terminal 122. The connection portion 15 melts to break the circuit or increases the impedance to extend the control short-circuit protection time, thereby protecting the power module 1. Figure 6a In the middle, two short-circuit suppression structures V are set on the input side of the upper and lower bridge arms, which can play the short-circuit suppression function more quickly when the upper and lower bridge arms are connected.

[0084] Figure 6b For another power module 1, the metal layer 112 includes multiple isolated sub-metal layers, including a first sub-metal layer 1121, a second sub-metal layer 1122, a third sub-metal layer 1123, a fourth sub-metal layer 1124, and a fifth sub-metal layer 1125. A second input terminal 122 is disposed on the second sub-metal layer 1122, specifically connected to the edge of the second sub-metal layer 1122. An output terminal 13 is disposed on the fourth sub-metal layer 1124, specifically connected to the edge of the fourth sub-metal layer 1124. A break D is formed between the fourth sub-metal layer 1124 and the second sub-metal layer 1122, and the second sub-metal layers 1122 and the fourth sub-metal layer 1124 on both sides of the break D are connected by a connecting portion 15. The second sub-metal layer 1122 is connected to the output terminal 13 via the connecting portion 15 and the fourth sub-metal layer 1124. The fifth sub-metal layer 1125 is connected to the first input terminal 121. The fifth sub-metal layer 1125 forms another break D with the first sub-metal layer 1121. The fifth sub-metal layers 1125 on both sides of the break D are connected to the first sub-metal layer 1121 through a connecting part 15. The first sub-metal layer 1121 is connected to the first input terminal 121 through a connecting part 15 and the fifth sub-metal layer 1125.

[0085] The fourth sub-metal layer 1124 and the second sub-metal layer 1122 are arranged at intervals along the first direction, and the fifth sub-metal layer 1125 and the first sub-metal layer 1121 are arranged at intervals along the first direction. This arrangement can adapt to the arrangement of the first input terminal 121 and the output terminal 13, thereby reducing the space occupied by the break D in the metal layer 112, which in turn optimizes the layout of the power module 1 and helps to reduce the size of the power module 1.

[0086] Figure 6b The bridge arm circuit topology formed by power module 1 shown can be referred to Figure 4d As shown. Combined with Figure 6b and Figure 4d As shown, one connection part 15 is disposed between multiple first switching devices 141 and the first input terminal 121, and another connection part 15 is disposed between multiple second switching devices 142 and the output terminal 13. When a direct connection occurs between the upper and lower bridge arms in the bridge arm circuit with the upper arm on and the lower arm off, a large current instantaneously flows through the connection part 15 connecting the multiple first switching devices 141 and the first input terminal 121. The connection part 15 melts to break the circuit or increases the impedance to extend the control short-circuit protection time, thereby protecting the power module 1. When a direct connection occurs between the upper and lower bridge arms in the bridge arm circuit with the lower arm on and the upper arm off, a large current instantaneously flows through the connection part 15 connecting the multiple second switching devices 142 and the output terminal 13. The connection part 15 melts to break the circuit or increases the impedance to extend the control short-circuit protection time, thereby protecting the power module 1. Figure 6c In another power module 1, the metal layer 112 includes multiple isolated sub-metal layers, including a first sub-metal layer 1121, a second sub-metal layer 1122, a third sub-metal layer 1123, a fourth sub-metal layer 1124, and a fifth sub-metal layer 1125. The first sub-metal layer 1121 is connected to a first input terminal 121. An output terminal 13 is disposed on the fourth sub-metal layer 1124, specifically connected to the edge of the fourth sub-metal layer 1124. A break D is formed between the fourth sub-metal layer 1124 and the second sub-metal layer 1122, and the second sub-metal layers 1122 and the fourth sub-metal layer 1124 on both sides of the break D are connected by a connecting portion 15. The second sub-metal layer 1122 is connected to the output terminal 13 via the connecting portion 15 and the fourth sub-metal layer 1124. The fifth sub-metal layer 1125 is connected to the second input terminal 122. The fifth sub-metal layer 1125 forms another break D with the third sub-metal layer 1123. The fifth sub-metal layer 1125 on both sides of the break D is connected to the third sub-metal layer 1123 through a connecting part 15. The third sub-metal layer 1123 is connected to the second input terminal 122 through a connecting part 15 and the fifth sub-metal layer 1125.

[0087] The fourth sub-metal layer 1124 and the second sub-metal layer 1122 are arranged at intervals along the first direction, and the fifth sub-metal layer 1125 and the third sub-metal layer 1123 are arranged at intervals along the first direction. This arrangement can be adapted to the arrangement of the second input terminal 122 and the output terminal 13, thereby reducing the space occupied by the break D in the metal layer 112, which in turn optimizes the layout of the power module 1 and helps to reduce the size of the power module 1.

[0088] Figure 6c The bridge arm circuit topology formed by power module 1 shown can be referred to Figure 4a As shown. Combined with Figure 6c and Figure 4a As shown, one connection part 15 is disposed between multiple second switching devices 142 and the second input terminal 122, and another connection part 15 is disposed between multiple first switching devices 141 and the output terminal 13. When a direct connection occurs between the upper and lower bridge arms in the bridge arm circuit with the upper arm on and the lower arm off, a large current instantaneously flows through the connection part 15 connecting the multiple first switching devices 141 and the output terminal 13. The connection part 15 melts to break the circuit or increases the impedance to extend the control short-circuit protection time, thereby protecting the power module 1. When a direct connection occurs between the upper and lower bridge arms in the bridge arm circuit with the lower arm on and the upper arm off, a large current instantaneously flows through the connection part 15 connecting the multiple second switching devices 142 and the second input terminal 122. The connection part 15 melts to break the circuit or increases the impedance to extend the control short-circuit protection time, thereby protecting the power module 1.

[0089] In the specific design of power module 1, the form of bridge arm circuit can be achieved by the number and layout of multiple power switching devices 14 and the connection method with metal layer 112 to realize different circuit connections.

[0090] like Figure 7a and Figure 7b The illustrated bridge arm circuit includes an upper bridge arm comprising at least two parallel upper bridge arm branches, each upper bridge arm branch having at least one power switching device. The lower bridge arm comprises at least two parallel lower bridge arm branches, each lower bridge arm branch having at least one power switching device.

[0091] like Figure 7a As shown, in order to prevent adverse consequences caused by shoot-through between the upper and lower bridge arms of the bridge arm circuit, the short-circuit suppression structure V of the upper bridge arm can be set in the main circuit of the upper bridge arm, and the short-circuit suppression structure V of the lower bridge arm can be set in the main circuit of the lower bridge arm. Figure 7aThe example illustrates that the short-circuit suppression structure V of the upper bridge arm is located between the bus output terminals of the two upper bridge arm branches and the midpoint M of the bridge arm, while the short-circuit suppression structure V of the lower bridge arm is located between the terminal a2 used to connect to the negative power input and the bus input terminals of the two lower bridge arm branches. Alternatively, the short-circuit suppression structure V of the upper bridge arm can also be located between the terminal a1 used to connect to the positive power input and the bus input terminals of the two upper bridge arm branches, and the short-circuit suppression structure V of the lower bridge arm can also be located between the bus output terminals of the two lower bridge arm branches and the midpoint M of the bridge arm.

[0092] like Figure 7b As shown, the short-circuit suppression structure V of the upper bridge arm can be set in each branch of the upper bridge arm, and the short-circuit suppression structure V of the lower bridge arm can be set in each branch of the lower bridge arm. Figure 7b The example illustrates an upper bridge arm comprising at least two short-circuit suppression structures V, with each upper bridge arm branch exemplarily located between the power switching device and the bus output of the branch. Alternatively, each upper bridge arm branch may also have its short-circuit suppression structure V located between the power switching device and the bus input of the branch. Figure 7b The example illustrates a lower bridge arm comprising at least two short-circuit suppression structures V, with the short-circuit suppression structure V for each lower bridge arm branch exemplarily located between the power switching device and the bus input of the branch. Alternatively, the short-circuit suppression structure V for each lower bridge arm branch may also be located between the power switching device and the bus input of the branch.

[0093] Figure 8a The present application provides a structure for a power module 1, wherein the upper arm of the power module 1 includes two upper arm branches and the lower arm includes two lower arm branches, for forming... Figure 7a The bridge arm circuit shown.

[0094] like Figure 8a As shown, the power module 1 includes two first input terminals 121 and one second input terminal 122. Both first input terminals 121 are used to connect to the positive terminal of the power supply, and the second input terminal 122 is used to connect to the negative terminal of the power supply. Along the second direction, the second input terminal 122 is arranged between the two first input terminals 121, and a gap exists between the second input terminal 122 and each first input terminal 121, meaning that the second input terminal 122 and each first input terminal 121 remain in contact.

[0095] During the operation of the bridge arm circuit formed by power module 1, both first input terminals 121 are used to connect to the upper bridge arm of the bridge arm circuit. The two first input terminals 121 can be connected to the input terminals of the upper bridge arm simultaneously, or they can be connected to two parallel branches of the upper bridge arm respectively. For example... Figure 8aAs shown, the metal layer 112 comprises multiple sub-metal layers, including two first sub-metal layers 1121, which are disposed on both sides of the second sub-metal layer 1122 along a second direction. One first sub-metal layer 1121 has one first input terminal 121, and the other first sub-metal layer 1121 has another first input terminal 121. Among the multiple first switching devices 141, a portion of the first switching devices 141 are disposed between one first sub-metal layer 1121 and the second sub-metal layer 1122, and another portion of the first switching devices 141 are disposed between the other first sub-metal layer 1121 and the second sub-metal layer 1122. The two first sub-metal layers 1121 are symmetrically positioned about the second sub-metal layer 1122, and the first switching devices 141 are symmetrically distributed about the second sub-metal layer 1122. Each second switching device 142 is disposed on the second sub-metal layer 1122. A portion of the second switching devices 142 are connected to the third sub-metal layer 1123 through a connector 16, and another portion of the second switching devices 142 are connected to the third sub-metal layer 1123 through another connector 16.

[0096] In one embodiment, the second sub-metal layer 1122 is U-shaped, and a plurality of second switching devices 142 are respectively arranged on both sides of the third sub-metal layer 1123, with the third sub-metal layer 1123 located between the two portions of the second switching devices 142.

[0097] like Figure 8aAs shown, as an example, the power module 1 includes two breaks D and two connecting portions 15. An output terminal 13 is disposed on the fourth sub-metal layer 1124, specifically connected to the edge of the fourth sub-metal layer 1124. A break D is formed between the fourth sub-metal layer 1124 and the second sub-metal layer 1122, and the second sub-metal layer 1122 and the fourth sub-metal layer 1124 on both sides of the break D are connected by a connecting portion 15. A second input terminal 122 is disposed on the fifth sub-metal layer 1125, specifically connected to the edge of the fifth sub-metal layer 1125. Another break D is formed between the fifth sub-metal layer 1125 and the third sub-metal layer 1123, and the fifth sub-metal layer 1125 and the third sub-metal layer 1123 on both sides of the break D are connected by a connecting portion 15. One connection portion 15 is connected between the main circuit of the lower bridge arm formed by multiple second switching devices 142 and the second input terminal 122, and another connection portion 15 is connected between the main circuit of the upper bridge arm formed by multiple first switching devices 141 and the output terminal 13. When a direct connection occurs between the upper and lower bridge arms in the upper bridge arm circuit (when the upper bridge arm is on and the lower bridge arm is off), a large current instantaneously flows through the connection portion 15 connecting the multiple first switching devices 141 and the output terminal 13. The connection portion 15 melts to break the circuit or increases the impedance to extend the control short-circuit protection time, thereby protecting the power module 1. When a direct connection occurs between the upper and lower bridge arms in the lower bridge arm circuit (when the upper bridge arm is on and the upper bridge arm is off), a large current instantaneously flows through the connection portion 15 connecting the multiple second switching devices 142 and the second input terminal 122. The connection portion 15 melts to break the circuit or increases the impedance to extend the control short-circuit protection time, thereby protecting the power module 1.

[0098] In the power module 1 provided in this application embodiment, the connection part 15 used to achieve short-circuit suppression can be implemented in various ways, such as... Figure 8a The structure of power module 1 shown is used as a reference. Figure 8b for Figure 8a The diagram shown is a structural schematic of power module 1 after being cut along the Z-shaped cross-section. Figure 8b The example illustrates an implementation of a block-shaped connector 15.

[0099] like Figure 8b As shown, in one embodiment, at least one of the two connecting portions 15 included in the power module 1 is a conductive block, which is embedded in the break D.

[0100] Taking the connection portion 15 connecting the fourth sub-metal layer 1124 and the second sub-metal layer 1122 as an example, the connection portion 15 is embedded in the break D between the fourth sub-metal layer 1124 and the second sub-metal layer 1122. Along the arrangement direction of the fourth sub-metal layer 1124 and the second sub-metal layer 1122, one end of the connection portion 15 is electrically connected to the fourth sub-metal layer 1124 in a surface contact manner, and the other end of the connection portion 15 is electrically connected to the second sub-metal layer 1122 in a surface contact manner. The surface contact type of electrical connection has a better effect. This connection portion 15 connects the fourth sub-metal layer 1124 and the second sub-metal layer 1122, realizing the electrical connection between multiple first switching devices 141 and the output terminal 13 in the upper bridge arm. The first switching devices 141 are not shown here. The break D and the corresponding connection portion 15 are used to form the short-circuit suppression structure V in the upper bridge arm circuit.

[0101] Taking the connection portion 15 connecting the fifth sub-metal layer 1125 and the third sub-metal layer 1123 as an example, the connection portion 15 is embedded in the break D between the fifth sub-metal layer 1125 and the third sub-metal layer 1123. Along the direction in which the fifth sub-metal layer 1125 is arranged with the third sub-metal layer 1123, one end of the connection portion 15 is electrically connected to the fifth sub-metal layer 1125 in a surface contact manner, and the other end of the connection portion 15 is electrically connected to the third sub-metal layer 1123 in a surface contact manner. This connection portion 15 connects the fifth sub-metal layer 1125 and the third sub-metal layer 1123, realizing the electrical connection between the multiple second switching devices 142 and the second input terminal 122 in the upper bridge arm. The break D and the corresponding connection portion 15 are used to form a short-circuit suppression structure V in the lower bridge arm circuit.

[0102] Combination Figure 8a and Figure 8b As shown, the material of the conductive block-shaped connection 15 can be selected and sized according to the short-circuit current or energy threshold. The melting point of the connection 15 is lower than that of the metal layer 112. When the upper and lower bridge arms are connected, if the current or energy passing through the connection 15 reaches the threshold, the connection 15 will melt, thus creating an open circuit in the circuit containing the connection 15. The material of the conductive block-shaped connection 15 can also be designed based on its thermal characteristics; the connection 15 can be a temperature-sensitive material. When the upper and lower bridge arms are connected, if the current or energy passing through the connection 15 reaches the threshold, the connection 15 can rapidly change its impedance characteristics, thereby suppressing current climb and giving the controller of the power conversion device more time to implement short-circuit protection. Specifically, the conductive block can be formed by filling the fracture surface D with filler and curing it, or it can be housed in the fracture surface D and welded to the metal layers 112 on both sides, resulting in a reliable and high-strength connection.

[0103] In one embodiment, along the thickness direction of the power module 1, that is, the thickness direction of the substrate 11, the thickness of the connecting portion 15 is the same as or approximately the same as the thickness of the metal layer 112. The surface of the connecting portion 15 facing the insulating base plate 111 is attached to the insulating base plate 111, and the surface of the connecting portion 15 away from the insulating base plate 111 is flush with or approximately flush with the surface of the metal layer 112.

[0104] During normal operation of the power module 1, the thickness of the connection portion 15 and the thickness of the metal layer 112 remain relatively consistent, which helps to maintain the stability and reliability of electrical signal transmission, and also helps to distribute the heat of the substrate 11 evenly, avoiding local overheating problems, thereby improving the overall heat dissipation effect.

[0105] Figure 9a and Figure 9b In another power module 1 structure, at least one connection portion 15 includes multiple bonding wires, with each bonding wire's two ends connected to the metal layers 112 on both sides of the break point D. Taking a connection portion 15 connecting the fourth sub-metal layer 1124 and the second sub-metal layer 1122 as an example, the two ends of the bonding wires included in the connection portion 15 are connected to the fourth sub-metal layer 1124 and the second sub-metal layer 1122, respectively. Taking a connection portion 15 connecting the fifth sub-metal layer 1125 and the third sub-metal layer 1123 as an example, the two ends of the bonding wires included in the connection portion 15 are connected to the fifth sub-metal layer 1125 and the third sub-metal layer 1123, respectively. The material, length, and wire diameter of the bonding wires included in each connection portion 15 are selected and sized according to the short-circuit current or energy threshold, and the melting point of the connection portion 15 is lower than the melting point of the metal layer 112. When the upper and lower bridge arms are directly connected, if the current or energy passing through the connection part 15 reaches a threshold, the connection part 15 will melt, thus creating an open circuit in the circuit containing the connection part 15. This provides more flexible bonding wire connections and can also reduce costs.

[0106] Figure 10a and Figure 10bIn another power module 1 structure, at least one connection portion 15 includes a conductive strip, the two ends of which overlap the surfaces of the metal layers 112 on both sides of the break D, away from the insulating base plate 111. Taking the connection portion 15 connecting the fourth sub-metal layer 1124 and the second sub-metal layer 1122 as an example, the two ends of the conductive strip included in the connection portion 15 overlap the surfaces of the fourth sub-metal layer 1124 and the second sub-metal layer 1122, away from the insulating base plate 111. Taking the connection portion 15 connecting the fifth sub-metal layer 1125 and the third sub-metal layer 1123 as an example, the two ends of the conductive strip included in the connection portion 15 overlap the surfaces of the fifth sub-metal layer 1125 and the third sub-metal layer 1123, away from the insulating base plate 111. The material and size of the conductive strip-type connector 15 can be selected based on the short-circuit current or energy threshold. When the upper and lower bridge arms are directly connected, if the current or energy passing through the connector 15 reaches the threshold, the connector 15 will melt, creating an open circuit in the circuit containing the connector 15. Alternatively, the material of the conductive strip-type connector 15 can be designed based on its thermal characteristics, making it a temperature-sensitive material. When the upper and lower bridge arms are directly connected, if the current or energy passing through the connector 15 reaches the threshold, the connector 15 can rapidly change its impedance characteristics, thereby suppressing current surge and giving the power conversion device controller more time to implement short-circuit protection. The conductive strip design is easy to maintain and replace, while maintaining good conductivity and mechanical strength.

[0107] In some embodiments, such as Figure 11 The power module 1 shown is related to... Figures 6a to 6c The difference in the power module 1 shown is that one of the breaks D can be formed in the structure of the other non-metallic layers 112 of the power module 1.

[0108] like Figure 11 As shown, metal layer 112 includes multiple isolated sub-metal layers, including a first sub-metal layer 1121, a second sub-metal layer 1122, a third sub-metal layer 1123, and a fourth sub-metal layer 1124. The second sub-metal layer 1122 is connected to the second input terminal 122. The fourth sub-metal layer 1124 is connected to the output terminal 13. A break D is formed between the fourth sub-metal layer 1124 and the second sub-metal layer 1122. The second sub-metal layer 1122 and the fourth sub-metal layer 1124 on both sides of the break D are connected by a connecting portion 15. The second sub-metal layer 1122 is connected to the output terminal 13 via the connecting portion 15 and the fourth sub-metal layer 1124. Multiple first switching devices 141 are connected to the second sub-metal layer 1122 via an adapter 16. The adapter 16 forms a break D, and the adapters 16 on both sides of the break D are connected by the connecting portion 15. The connecting part 15 here can also be at least one of conductive block, bonding wire, and conductive strip. Figure 11 The power module 1 shown may be configured as follows: Figure 4c The bridge arm circuit shown.

[0109] It should be understood that, depending on the different bridge arm circuit designs, Figure 11 The positions of the break point D and the connection portion 15 shown can also be adjusted as needed. In some embodiments, the break point D may also be formed in the electrical connection structure such as the pins or bonding wires of the device.

[0110] In summary, the power module 1 provided in this application embodiment, through the design of the circuit connections in the power module 1 with breaks, connects at least one short-circuit suppression structure V in series in the upper and lower bridge arms of the bridge arm circuit formed by the power module 1. This short-circuit suppression structure V can disconnect the circuit or increase its own impedance when the upper and lower bridge arms are directly connected, preventing damage to the power module 1 caused by the direct connection and protecting both the devices and the power module 1. In scenarios where multiple power modules 1 are connected to form multiple parallel bridge arm circuits, if the upper bridge arm of one power module's bridge arm circuit is directly connected to the lower bridge arm of another power module's bridge arm circuit, at least one of the short-circuit suppression structures V in the upper and lower bridge arms can disconnect the circuit or increase the impedance, thus also achieving short-circuit suppression and preventing inter-phase bridge arm short-circuit faults.

[0111] The power module 1 provided in this application embodiment can be a single-side cooling power module, a dual-side cooling power module, etc. Of course, the application scenarios of this power module 1 are not limited to electric vehicles, but can also be applied to power conversion circuits in other scenarios such as photovoltaic systems and energy storage systems that require prevention of bridge arm shoot-through.

[0112] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A power module, characterized in that, The power module includes a substrate, a first input terminal, a second input terminal, an output terminal, a first switching device, a second switching device, and two connecting parts; The first switching device and the second switching device are disposed on the substrate. The first switching device and the second switching device are connected to form a bridge arm circuit. The two ends of the bridge arm circuit are respectively connected to the first input terminal and the second input terminal. The midpoint of the bridge arm circuit is connected to the output terminal. The first switching device is connected between the first input terminal and the midpoint of the bridge arm, and the second switching device is connected between the second input terminal and the midpoint of the bridge arm. The power module is provided with two breaks. One break is used to block the circuit connection between the first input terminal and the output terminal, and the other break is used to block the circuit connection between the second input terminal and the output terminal. The circuits on both sides of each break are connected by a connection part, and the melting point of the connection part is lower than the melting point of the metal layer of the substrate.

2. The power module as described in claim 1, characterized in that, Each of the connectors is used to either melt or increase impedance when a reference value reaches a set threshold, the reference value including at least one of the current passing through the connector when the bridge arm circuit is through or the heat generated by the connector.

3. The power module as described in claim 1 or 2, characterized in that, One of the breaks is located between the first switching device and the first input terminal or between the first switching device and the output terminal, and the other break is located between the second switching device and the second input terminal or between the second switching device and the output terminal.

4. The power module as described in any one of claims 1-3, characterized in that, At least one of the two breaks is disposed on the substrate.

5. The power module as described in claim 4, characterized in that, The substrate includes an insulating base plate and a metal layer disposed on the insulating base plate, wherein the first input terminal, the second input terminal, the output terminal, the first switching device, and the second switching device are disposed on the metal layer; One of the breaks is located in the metal layer between the first input terminal and the first switching device or in the metal layer between the first switching device and the output terminal, and the other break is located in the metal layer between the second input terminal and the second switching device or in the metal layer between the second switching device and the output terminal.

6. The power module as described in claim 5, characterized in that, The metal layer includes a phase-isolated first sub-metal layer, a second sub-metal layer, a third sub-metal layer, a fourth sub-metal layer, and a fifth sub-metal layer; The first switching device is disposed on the first sub-metal layer and connected to the second sub-metal layer, the second switching device is disposed on the second sub-metal layer and connected to the third sub-metal layer, and the output terminal is disposed on the fourth sub-metal layer; The first input terminal is disposed on the fifth sub-metal layer, one of the breaks is located between the fourth sub-metal layer and the second sub-metal layer, and the other break is located between the fifth sub-metal layer and the first sub-metal layer; Alternatively, the second input terminal is disposed on the fifth sub-metal layer, one of the breaks is located between the fourth sub-metal layer and the second sub-metal layer, and the other break is located between the fifth sub-metal layer and the third sub-metal layer.

7. The power module as described in claim 5, characterized in that, The metal layer includes a phase-isolated first sub-metal layer, a second sub-metal layer, a third sub-metal layer, a fourth sub-metal layer, and a fifth sub-metal layer; The first switching device is disposed on the first sub-metal layer and connected to the second sub-metal layer, the second switching device is disposed on the second sub-metal layer and connected to the third sub-metal layer, the first input terminal is disposed on the fourth sub-metal layer, and the second input terminal is disposed on the fifth sub-metal layer; One of the fractures is located between the fourth sub-metal layer and the first sub-metal layer, and the other fracture is located between the fifth sub-metal layer and the third sub-metal layer.

8. The power module as described in claim 6 or 7, characterized in that, The power module includes an input terminal and an output terminal opposite to each other along a first direction. The first input terminal and the second input terminal are arranged adjacent to each other along a second direction at the input terminal, and the output terminal is disposed at the output terminal. Both the first direction and the second direction are perpendicular to the thickness direction of the substrate, and the first direction is perpendicular to the second direction. The first sub-metal layer and the second sub-metal layer are arranged at intervals along the second direction, and at least a portion of the third sub-metal layer is arranged at intervals along the second direction on the side of the second sub-metal layer away from the first sub-metal layer.

9. The power module according to any one of claims 5-8, characterized in that, At least one of the connecting parts is a conductive block, which is housed within the fracture and is in contact with the metal layers on both sides of the fracture.

10. The power module as described in claim 9, characterized in that, The surface of the conductive block facing the insulating base plate is in contact with the insulating base plate, and the surface of the conductive block away from the insulating base plate is flush with the surface of the metal layer away from the insulating base plate.

11. The power module according to any one of claims 5-8, characterized in that, At least one of the connecting portions includes a plurality of bonding wires, and the two ends of each bonding wire are respectively connected to the metal layers on both sides of the fracture.

12. The power module according to any one of claims 5-8, characterized in that, At least one of the connecting parts is a conductive strip, and the two ends of the conductive strip are respectively attached to the metal layers on both sides of the break, away from the surface of the insulating base plate.

13. The power module according to any one of claims 1-12, characterized in that, At least one of the connecting parts is made of a temperature-sensitive material.

14. A powertrain, characterized in that, The powertrain includes a controller and a motor, the controller including a plurality of power modules as described in any one of claims 1-13; The first input terminal and the second input terminal of each power module are respectively used to connect to the positive and negative terminals of the power supply, and the output terminal of each power module is used to connect to one phase circuit of the motor.

15. An electric vehicle, characterized in that, The electric vehicle includes a power source, wheels, and a powertrain as described in claim 14, wherein the powertrain's power conversion device receives direct current from the power source and converts the direct current into alternating current for output to the motor, and the motor is drivenly connected to the wheels.

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