Vehicle with battery power system and interleaved power modules

Abstract

Vehicle with battery power system and interleaved power module. A power module for a battery power system, such as for a vehicle, includes a voltage bus, a printed circuit board (PCB), first and second power switch sets, and a decoupling capacitor. The PCB is positioned between parallel positive and negative buses. The first power switch set is connected to the positive bus adjacent a first side of the PCB and operates as a high-side switch. The second power switch set is connected to the negative bus adjacent a second side of the PCB and operates as a low-side switch. The bus is between the current paths of the high-side and low-side switches. The decoupling capacitor is connected to the local voltage bus on the first side of the PCB. High-side and low-side gate driver integrated circuits can be contained in a gap or space separating the switch sets from the respective first and second sides of the PCB.

Description

[0001] introduce

[0002] This disclosure relates to a battery power system having a direct current (DC) power source, such as a high-voltage electrochemical battery pack. Within the battery power system, the DC output voltage provided by the battery pack can be converted to an alternating current (AC) voltage via an inverter. The AC output voltage from the inverter is directed to the phase windings of a rotating electric machine, such as an electric traction motor of a representative vehicle. The energized motor responds to a coupled load via rotation and torque transmission. The battery power system may also include a DC-to-DC voltage converter operable to selectively increase or decrease the DC voltage level on the main DC voltage bus as needed.

[0003] Interleaved power modules are dedicated power conversion architectures used in high-current, high-power-density applications. Modern electric vehicle propulsion systems, for example, can utilize interleaved power modules within resident inverter or converter architectures. An interleaved configuration interconnects multiple parallel power stages to produce the desired output voltage. Switching control signals for the various power stages can be phase-shifted to produce a ripple cancellation effect. By avoiding the need to share current across common components, interleaved converters can distribute current among smaller hardware components to help reduce thermal stress. Summary of the Invention

[0004] This document discloses an interleaved power module for use in battery power systems. Battery power systems can then be used in electrified mobile or stationary systems, such as, but not limited to, electric or hybrid electric vehicles. Specifically, the power module of this disclosure employs a folded / multilayer printed circuit board (PCB), i.e., a PCB with parallel switching dies constructed as described herein, to optimally couple loop components and thereby reduce inductance, particularly parasitic loop inductance and stray inductance. The PCB of this disclosure is configured as a four-layer, multi-sided PCB with power devices mounted. Without this teaching, a controller for a power module might attempt to retard the switching speed of solid-state switches in the power module to reduce current / voltage overshoot. However, such control actions can lead to higher losses, reduced operating range (for mobile system applications), and overall performance degradation. Therefore, the PCB construction of the power module described herein is designed to address these and other potential performance issues within battery power systems.

[0005] Specifically, the power module according to an embodiment includes a switching output node (SW), a local voltage bus, and a multilayer PCB positioned between positive and negative buses (busbars) of the local voltage bus. The positive and negative buses are respectively connected to the positive input node (HV). + ) and negative input node (HV) - The first power switch set is connected to the positive bus adjacent to the first side of the PCB, wherein the first power switch set is at the positive input node (HV). + There is a first / high-side current path between the power switch group (HV) and the switch output node (SW), such as the top side in a representative configuration. The second power switch group is connected to the negative bus adjacent to the second side of the PCB, where the second power switch group has a first high-side current path between the negative input node (HV). - There is a second / low-side (e.g., bottom-side) current path between the high-side current path and the switch output node (SW). Multiple decoupling capacitors are connected to the positive and negative buses, and the local voltage bus bus is located between the first / high-side current path and the second / low-side current path.

[0006] In a possible embodiment, the first and second power switch groups are surface-mounted to the first and second sides of the PCB, respectively. Optionally, the high-side and low-side power switches may be embodied as metal-oxide-semiconductor field-effect transistors (MOSFETs), wherein other solid-state configurations are possible within the scope of this disclosure as set forth below.

[0007] In different implementations, the power module includes at least six decoupling capacitors, or possibly at least twenty-four decoupling capacitors. In the latter case, the power module can be configured as a three-phase (or more) multilevel converter, an example embodiment of which is described in detail below.

[0008] One or more shunt resistors or other current sensors can be mounted on the first / top side of the PCB.

[0009] In another embodiment, the power module includes gate driver integrated circuits (ICs), such as a high-side gate driver IC and a low-side gate driver IC in a possible configuration. In a possible implementation, the high-side and low-side gate driver ICs are placed on respective top and bottom sides of a PCB, with symmetrical gate driver traces and overlapping gate loops traversing the inner layers of the PCB. A first / high-side power switch group is separated from a first side of the PCB by a first space or gap, wherein the first gap contains the high-side gate driver IC. Similarly, a second power switch group is separated from a second / bottom side of the PCB by a second gap containing the low-side gate driver IC.

[0010] In contrast to surface mounting, in an alternative construction of the power module, the first and second power switch groups can be embedded within a PCB. In such a configuration, the PCB can define a cooling channel extending between the first and second power switch groups. The cooling channel can contain a thermally conductive cooling material for simultaneously cooling the first and second semiconductor switch groups.

[0011] This document also discloses a battery power system. The battery power system may include a main DC voltage bus, an electrochemical battery pack connectable to the main DC voltage bus, and a power module operable to power a load, such as one or more electric traction motors or other electric motors, during the discharge mode of the battery pack. The power module includes a local voltage bus connectable to the main DC voltage bus, wherein the local voltage bus has positive and negative buses arranged in respective parallel planes. In this embodiment, a PCB is positioned between the positive and negative buses. A first power switch group connected to the positive busbar adjacent to a first / top side of the PCB is configured to operate as a high-side switch of the power module. Similarly, a second power switch group is connected to the negative busbar adjacent to a second / bottom side of the PCB. The second power switch group operates as a low-side switch in the power module. The positive and negative buses are located between the current paths of the high-side and low-side switches. Decoupling capacitors are connected to the positive and negative buses, for example, on the first / top side of the PCB.

[0012] According to another aspect of this disclosure, a vehicle includes a vehicle body, road wheels connected to the vehicle body, and a battery power system. The battery power system, operable as a drive system to provide power to one or more road wheels to propel the vehicle, includes a main DC voltage bus, a traction battery pack connectable to the main DC voltage bus, and a multiphase AC propulsion or traction motor. The battery power system further includes a power inverter operable to power the electric traction motor during a discharge mode of the battery pack.

[0013] In a representative embodiment of the vehicle, the power module can be used as part of a power inverter and includes a local voltage bus connected to the main DC voltage bus. The local voltage bus includes positive and negative buses arranged in a parallel plane. The power module also includes a multilayer PCB positioned between the positive and negative buses. A first power switch group is connected to the positive bus adjacent to a first side of the PCB and is configured to operate as a high-side switch in the power module as indicated above. A second power switch group is connected to the negative bus adjacent to a second side of the PCB and is configured to operate as a low-side switch in the power module. In this particular implementation, the bus is located between the current paths of the high-side and low-side switches. At least twenty-four decoupling capacitors are connected to the local voltage bus, for example, on the first side of the PCB. In this representative implementation, the power module is configured as a three-phase multilevel converter.

[0014] A power module includes: a switch output node (SW); and a local voltage bus having a positive bus and a negative bus arranged on corresponding parallel planes, the positive bus and the negative bus being connected to a positive input node (HV). + ) and negative input node (HV) - ); Printed circuit board (PCB), positioned between the positive bus and the negative bus; First power switch group, connected to the positive bus adjacent to the first side of the PCB, the first power switch group at the positive input node (HV + There is a first / high-side current path between the input node (HV) and the switch output node (SW); a second power switch group is connected to the negative bus adjacent to the second side of the PCB, and the second power switch group is connected to the negative input node (HV). - A second / low-side current path exists between the power switch and the switch output node (SW); and multiple decoupling capacitors are connected to the positive and negative buses, with a local voltage bus bus located between the first / high-side current path and the second / low-side current path. A first power switch and a second power switch group are surface-mounted to a first side and a second side of the PCB, respectively. The first and second power switch groups are configured as metal-oxide-semiconductor field-effect transistors (MOSFETs). The multiple decoupling capacitors include at least six decoupling capacitors. The at least six decoupling capacitors include twenty-four decoupling capacitors, and the power module is configured as a three-phase multilevel converter. Further comprising: one or more current sensors mounted to the PCB. The one or more current sensors include one or more shunt resistors. Further comprising: a gate driver integrated circuit (IC) connected to the PCB, close to the first and second power switch groups. The gate driver IC includes a high-side gate driver integrated circuit (IC) and a low-side gate driver IC, wherein a first power switch group is separated from a first side of the PCB by a first gap, the first gap containing the high-side gate driver IC; and a second power switch group is separated from a second side of the PCB by a second gap, the second gap containing the low-side gate driver IC. The first and second power switch groups are embedded within the PCB. A gap is defined in the PCB between the first and second power switch groups; and the gap is filled with a thermally conductive material operable for cooling the first and second power switch groups.

[0015] A battery power system for supplying power to a load includes: a main DC voltage bus; a battery pack connectable to the DC voltage bus; and a power module operable to supply power to the load during a discharge mode of the battery pack, the power module including: a switch output node (SW); and a local voltage bus connected to the main DC voltage bus and having a positive bus and a negative bus arranged on respective parallel planes, the positive bus and the negative bus being connected to a positive input node (HV). + ) and negative input node (HV) - ); Printed circuit board (PCB), positioned between the positive bus and the negative bus; First power switch group, connected to the positive bus adjacent to the first side of the PCB, the first power switch group at the positive input node (HV + There is a first / high-side current path between the input node (HV) and the switch output node (SW); a second power switch group is connected to the negative bus adjacent to the second side of the PCB, and the second power switch group is connected to the negative input node (HV). - A second / low-side current path exists between the power module and the switch output node (SW); and multiple decoupling capacitors are connected to the positive and negative buses, with a local voltage bus located between the first / high-side current path and the second / low-side current path. Further comprising: a load, wherein the load includes an electric motor. The electric motor is a multiphase AC traction motor, and the power module is configured as a three-phase multilevel converter having a set of twenty-four decoupling capacitors as multiple decoupling capacitors. The power module includes a gate driver integrated circuit (IC) having a high-side gate driver IC and a low-side gate driver IC, wherein: a first power switch group is separated from a first side of the PCB by a first gap, in which the high-side gate driver IC is contained; and a second power switch group is separated from a second side of the PCB by a second gap, in which the low-side gate driver IC is contained. The first and second power switch groups are embedded within the PCB.

[0016] The PCB defines an elongated cooling channel that extends between and is parallel to the respective planes of the second power switch and the first power switch group; and the elongated cooling channel is filled with a thermally conductive material.

[0017] A vehicle includes: a vehicle body; an assembly of road wheels connected to the vehicle body; and a battery power system operable to power one or more of the road wheels in the assembly to propel the vehicle, the battery power system including: a main direct current (DC) voltage bus; a battery pack connectable to the main DC voltage bus; a multiphase alternating current (AC) electric traction motor having output members connected to one or more road wheels; and a power module connected to the electric traction motor and operable to power the electric traction motor during a discharge mode of the battery pack, the power module including: a switch output node (SW); a local voltage bus connected to the main DC voltage bus and having a positive bus and a negative bus arranged on respective parallel planes, the positive bus and the negative bus being respectively connected to a positive input node (HV). + ) and negative input node (HV) - ); Printed circuit board (PCB), positioned between the positive bus and the negative bus; First power switch group, connected to the positive bus adjacent to the first side of the PCB, the first power switch group at the positive input node (HV + There is a first / high-side current path between the input node (HV) and the switch output node (SW); a second power switch group is connected to the negative bus adjacent to the second side of the PCB, and the second power switch group is connected to the negative input node (HV). - A second / low-side current path exists between the power module and the switch output node (SW); and at least twenty-four decoupling capacitors are connected to a local voltage bus on a first side of the PCB, wherein the power module is configured as a three-phase multilevel converter. The power module includes: a high-side gate driver integrated circuit (IC); and a low-side gate driver IC, wherein: a first power switch group is separated from the first side of the PCB by a first gap, in which the high-side gate driver IC is contained; and a second power switch group is separated from the second side of the PCB by a second gap, in which the low-side gate driver IC is contained, wherein the first and second power switch groups are embedded within the PCB. The PCB defines a cooling channel extending between the first and second power switch groups embedded within the PCB.

[0018] The foregoing features and advantages, as well as other features and accompanying advantages, of this disclosure will readily become apparent from the following detailed description of illustrative examples and models for carrying out this disclosure when considered in conjunction with the accompanying drawings and appended claims. Furthermore, this disclosure explicitly includes combinations and sub-combinations of the elements and features presented above and below. Attached Figure Description

[0019] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate implementations of this disclosure and are considered together with the specification for explaining the principles of this disclosure.

[0020] Figure 1This is an illustration of a battery power system for a representative vehicle, wherein the battery power system includes an interleaved power module according to this disclosure.

[0021] Figure 2 This is a schematic circuit diagram showing the high current and low current paths through the power module.

[0022] Figure 3 This is a side view diagram of a power module constructed based on a representative three-phase design.

[0023] Figure 4A and 4B yes Figure 3 The diagram shows the corresponding top and bottom views of the power module.

[0024] Figure 5 yes Figure 3 The diagram shows a plan view of an alternative construction of a representative three-phase power module.

[0025] Figure 6 This is a side view illustration of a power module based on a possible embedded configuration.

[0026] Figure 7 It has an integrated cooling channel. Figure 6 A side view of the power module.

[0027] Figure 8 yes Figure 3 A side view illustration of an alternative configuration of the power module, which includes separate gate driver integrated circuits disposed between the high-side and low-side switch groups of the power module.

[0028] This disclosure may be modified or embodied in alternative forms, wherein representative embodiments are shown in the accompanying drawings and described in detail below. The inventive step of this disclosure is not limited to the disclosed embodiments. Rather, this disclosure is intended to cover alternatives that fall within the scope of this disclosure as defined by the appended claims. Detailed Implementation

[0029] Referring to the accompanying drawings, where the same reference numerals are used throughout several views to refer to the same features, Figure 1 A battery power system 10 having a power module 30 constructed according to this disclosure is depicted. Reference is made below. Figure 2-8As described, the power module 30 has a folded multilayer topology, i.e., a topology in which high-side (positive) and low-side (negative) solid-state / semiconductor power switch chips or dies are symmetrically mounted to opposite sides of a printed circuit board substrate. In some implementations, thermal impedance is also reduced via dual-side cooling features. Among other potential benefits, the multilayer architecture of the power module 30 in the high-speed switching circuit of the battery power system 10 enables symmetrical gate loops to reduce stray inductance during switching operations, which in turn minimizes switching losses and electromagnetic interference. Such benefits are achieved herein through the principle of magnetic field cancellation.

[0030] In possible scenarios, Figure 1 The battery-powered system 10 can be used as part of a mobile system 11, such as a motor vehicle 12, for example, in Figure 1 The (fully) battery-electric or hybrid-electric vehicle shown is illustrated. In such embodiments, the motor vehicle 12 may include a vehicle body 14 connected to a set of road wheels 16. The battery power system 10 is operable to power one or more road wheels 16 to propel the motor vehicle 12. Other mobility systems 11 are conceivable within the scope of this disclosure, such as, but not limited to, robots, factory equipment, mobile platforms, farm equipment, aircraft, rail vehicles / trains, boats, etc. Fixed versions of the mobility system 11 can also benefit from this teaching, such as hoists, conveyor systems, and the like. For the sake of consistency, the battery power system 10 will be described below as... Figure 1 The system is an integrated system of a representative motor vehicle 12, without limiting the use of the battery power system 10 to vehicle applications.

[0031] Battery power system 10 includes a high-voltage electrochemical battery pack (B HV Battery pack 20, for example, in a representative embodiment, is approximately 400V to approximately 800V, and a main DC voltage bus (VDC) 24 has positive and negative voltage rails (+, -). Battery pack 20 can be connected to the main DC voltage bus 24 via a set of relays or contactors (not shown). Although for the sake of simplicity, from Figure 1 The details are omitted, but battery pack 20 includes a suitable number of electrochemical battery cells, such as lithium-ion batteries, including lithium-ion nickel manganese cobalt (NMC), lithium-ion nickel cobalt aluminum (NCA), lithium iron phosphate (LFP), etc. Such battery pack 20 can be connected to / disconnected from the main DC voltage bus 24 as needed via the operation of the contactor described above, for example, when the vehicle 12 is shut off / disconnected in response to a threshold force on the vehicle 12, during an electrical fault, or before performing maintenance on high-voltage components.

[0032] In a possible configuration, the main DC voltage bus 24 can be connected to a power inverter module (PIM) 22, wherein in one or more embodiments, the PIM 22 includes a power module 30. The PIM 22 can be connected to a multiphase AC electric traction motor (M... E 18, wherein PIM 22 is operable to power the phase windings 19 of the electric traction motor 18 during the discharge mode of the battery pack 20. In such an implementation, the battery power system 10 may include an AC voltage bus 26 that supplies AC voltage (VAC) to the electric traction motor 18. The electric traction motor 18 in such a configuration includes individual phase windings 19, such as nominal (a, b, c) phases or (u, v, w) phases in a typical three-phase configuration. Such phase windings 19 are wired / connected to the AC voltage bus 26.

[0033] exist Figure 1 In the representative vehicle embodiment illustrated in the diagram, a rotatable output member 180 of the electric traction motor 18 is connected to a load of exemplary form, consisting of one or more road wheels 16. Discharge from the battery pack 20 delivers motor torque (arrow T) to the road wheels 16 via the output member 180. O This has the effect of energizing PIM 22. This, in turn, causes the rotor (not shown) of the electric traction motor 18 to rotate the road wheel 16 and thus propel the motor vehicle 12.

[0034] Figure 1 The battery power system 10 illustrated in the diagram may include additional components depending on its configuration. For example, an auxiliary power module (APM) 28, i.e., a DC-to-DC converter, which in some implementations may include a power module 30, may be connected to the main DC voltage bus 24 and the auxiliary voltage bus 240. The auxiliary voltage bus 240 may be connected to an auxiliary battery (B... AUX )200, for example, a nominal 12-15V lead-acid starting battery. Therefore, the voltage level of the auxiliary voltage bus 240 is substantially lower than the high voltage level present on the DC voltage bus 24.

[0035] The battery power system 10 may also include an electronic control unit (ECU) 50, which is operable to output signals electronically (arrow CC). O The ECU 50 controls various components of the battery power system 10. For example, the ECU 50 can be programmed to control the on / off switching states of the solid-state switches that make up the power module 30, as shown in the following reference. Figure 2-8 A detailed explanation is provided. ECU 50 can also be configured to respond to generated or received electronic input signals (arrow CC). IFor example, during the propulsion mode of the motor vehicle 12, the output torque requested or autonomously requested by the driver is controlled via the power module 30 to control the operating state of the electric traction motor 18. Figure 1 The ECU 50 may be equipped with one or more processors (P) 52 in the form of, for example, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a central processing unit, etc. The ECU 50 also includes a computer-readable storage medium (or media), namely a memory (M) 54, which has the form of one or more non-transitory memory components, such as read-only memory (ROM), optical or magnetic media, etc.

[0036] The non-transitory memory component of memory 54 is configured to store machine-readable instructions in the form of one or more software or firmware programs or routines, one or more combinational logic circuits, one or more input / output circuits and devices, signal conditioning and buffering circuits, and other components accessible by one or more processors to provide the aforementioned functionality. The one or more input / output circuits and devices include analog / digital inverters and associated devices for monitoring inputs from sensors at a preset sampling frequency or in response to trigger events. Software, firmware, programs, instructions, control routines, code, algorithms, and similar terms refer to a set of instructions executable by the controller, including calibration and lookup tables.

[0037] Now for reference Figure 2 To illustrate this clearly, a circuit diagram is provided to depict the situation when... Figure 1 The power module 30 operates when the electric traction motor 18 or another load is powered. The power module 30 includes components ultimately connected to... Figure 1 The main DC voltage bus 24 has a local voltage bus 34, wherein the power module 30 has a positive bus 34 arranged in a parallel plane. + and negative busbar 34 - For clarity, the positive and negative high-voltage connection nodes are also labeled HV, respectively. + and HV - .

[0038] As part of the power module 30, the switching circuit 32 includes first and second semiconductor-based / solid-state power switch groups 32H and 32L, where "H" and "L" represent "high side" (connected to the positive bus 34). + ) and the "low side" (connected to the negative voltage rail 34-). Multiple decoupling capacitors 36 (e.g., DC link capacitors C1, C2, and C3) are connected to the local voltage bus 34, i.e., across the positive bus 34. + and negative voltage rail 34 - As shown, the corresponding first and second power switch groups 32H and 32L are also connected to the corresponding positive and negative buses 34.+ and 34 - The output node (SW) of power module 30 is illustrated on the output side of switching circuit 32.

[0039] Different high-side and low-side current paths (I) are shown by switching circuit 32. H and I L As described below, the positive busbar 34 + and negative busbar 34 - Located on the high-side and low-side switches, i.e., the corresponding first and second power switch groups 32H and 32L, the two current paths (I) H and I L Between ) . Current path (I H and I L ) Through the positive and negative busbars 34 on opposite sides + 34 - It carries transient current ripple in the decoupling capacitor 36.

[0040] As those skilled in the art will appreciate, interleaved inverter topologies have power loops in which relatively high-value or high-amplitude currents (“high currents”) flow to the positive rail-connected / high-side (HS) power module, to the negative rail-connected / low-side (LS) power module, and back again. This type of loop tends to generate magnetic fields and form undesirable parasitic inductance. With the adoption of higher-temperature, faster-switching solid-state power switches, such as silicon carbide (SiC) and gallium nitride (GaN) metal-oxide-semiconductor field-effect transistors (MOSFETs), parasitic inductances of approximately 15 nano-Henry (nH) or less in emerging inverter circuit architectures can still cause relatively large induced voltage or current spikes, potentially compromising the structural integrity or functionality of inverters or converters using switching circuitry 32. The same parasitic inductance can also cause ringing and electromagnetic interference.

[0041] refer to Figure 3 The power module 30 of the various embodiments described below is based on a folded or multilayer printed circuit board (PCB) 31. Therefore, the PCB 31 has opposing first and second sides 31-1 and 31-2 arranged in a parallel plane. Figure 3 From a non-limiting perspective, the first side 31-1 is the top surface or upper surface of PCB 31, while the second side 31-2 is the bottom surface or lower surface of PCB 31. However, the orientation of the power module 30 can vary depending on the application, and therefore the top / bottom designation is application-specific. PCB 31 is positioned on the positive busbar 34. + and negative busbar 34 -Between them, the local voltage bus 34 is connected to the PCB 31 via terminals 33 or using solder or welded connectors, such as threaded fasteners or rivets as shown. Although the positive bus 34 + It exists at the first side 31-1 of PCB 31 and the negative bus 34 - It exists on the second side 31-2 of PCB 31, but the negative bus 34 - Part of this also exists on the first side 31-1. That is, conductive vias 38, such as copper traces or fillers, can extend between the first and second sides 31-1 and 31-2 of the PCB 31, as shown, to connect the negative busbars 34 located on the opposite first and second sides 31-1 and 31-2. - The segment or part. Therefore, negative busbar 34 - This is considered to be multi-layered and available on both sides of PCB 31.

[0042] In this configuration, the positive busbar 34 is connected to the first side 31-1 of the PCB 31. + The first power switch group 32H is configured to operate as a high-side switch in the power module 30 as noted above. Similarly, the second power switch group 34L is connected to the negative bus 34 adjacent to the second side 31-2 of the PCB 31. - In this implementation, the decoupling capacitor 36 is connected to the positive and negative busbars 34 on the first side 31-1 of the PCB 31. + and 34 - .

[0043] exist Figure 3 In a non-limiting embodiment, the first power switch group 32H and the second power switch group 32L are surface-mounted to the first side 31-1 and the second side 31-2 of the PCB 31, respectively. The high-side switch 32H and the low-side switch 32L can be configured as follows: Figure 2 The representative configuration shown is a metal-oxide-semiconductor field-effect transistor (MOSFET), or in other implementations it may be configured as an insulated-gate bipolar transistor (IGBT), thyristor, junction field-effect transistor (JFET), or another solid-state switch suitable for the application. Therefore, Figure 3 The MOSET embodiments are non-limiting.

[0044] Figure 4A and 4B The diagrams show simplified top and bottom views of the power module 30, where the local voltage bus 34 is connected to the PCB 31 via terminal 33. For example, as shown in... Figure 4B As shown, the fillet (CC) reduces the positive generatrix by 34. + and negative busbar 34 -The electric field strength in the gap between them. Positive busbar 34 + and negative busbar 34 - from Figure 4A As can be seen in the perspective view, the negative generatrix is ​​34. - exist Figure 4B As shown (i.e., the lower side of power module 30), the negative bus 34 is located at the first side 31-1 of PCB 31. - The exposed portion is via through hole 38 ( Figure 3 Connected to negative busbar 34 - The remaining part. See above for reference. Figure 3 As indicated, the decoupling capacitor 36 is connected to the voltage bus 34, for example, on the first side 31-1 of the PCB 31. In this exemplary configuration, six decoupling capacitors 36 are used to interconnect the respective positive and negative buses 34. + and 34 - .

[0045] exist Figure 4A and 4B In this configuration, the power module 30 may include a current sensor 39 mounted to the first side 31-1 of the PCB 31. For example, the current sensor 39 may include a pair of current sensors 39 in the form of integrated shunt resistors (one for each of the first and second power switch groups 32H and 32L), or another current sensing element suitable for the application, such as a Hall effect or fluxgate current sensor, a magnetoresistive sensor, etc.

[0046] Figure 4A The representative power module 30 topology illustrated in the diagram may also include a gate driver integrated circuit (GDIC) 40, ideally positioned close to the chip / die that hosts the first / high-side power switch group 32H and the second / low-side power switch group 32L. The GDIC 40 is operable to control the on / off states of the MOSFETs or other solid-state switches of the switch groups 32H and 32L, and may be combined with... Figure 1 ECU 50. As those skilled in the art will understand, when driving Figure 2 When the gate terminal of a MOSFET is in a non-restrictive configuration, a gate driver such as the representative GDIC 40 can operate to amplify power signals from the ECU 50 or other external controllers. The GDIC 40 can also perform circuit protection functions such as current limiting and thermal protection.

[0047] Brief Reference Figure 5 This teaching and associated benefits can be extended to multiphase AC applications using power module 300. For example, in a representative implementation, power module 300 can be configured as a three-phase multilevel converter. Although in Figure 5The diagram illustrates an exemplary three-phase implementation; however, those skilled in the art will appreciate that, within the scope of this disclosure, the circuit topology can be extended to include additional phases, such as six-phase, nine-phase, etc. Such higher-phase implementations can be used for... Figure 1 In the vehicle implementation, this reduces torque ripple and increases fault tolerance, albeit at the cost of increased circuit complexity.

[0048] as Figure 3 and Figures 4A-4B Similar to the embodiment, the symmetrical layout of the power module 300 places its local voltage bus 34 at Figure 2 High-side and low-side current paths I H I L Between them, optimal current sharing is used between parallel dies. In this circuit topology, twenty-four decoupling capacitors 36 are used to interconnect the positive and negative buses 34. + and 34 - The output buses 340U, 340V, and 340W (for nominal u, v, w phases) can be connected to... Figure 1 Phase winding 19 is used to power the electric traction motor 18 in representative transportation applications, such as EV propulsion. Although omitted for simplicity of illustration, the power module 300 may also include... Figure 4A The GDIC 40 and current sensor 39 are shown above. Additionally, a parallel power switch 32H ( Figure 4A The gate loop traces between the gates are also symmetrically designed on PCB 31 to improve dynamic current sharing balance.

[0049] The power modules 30 and 300 described above can alternatively be implemented by embedding the first (high-side) power switch group 32H and the second (low-side) power switch group 32L within the PCB 31. This alternative construction... Figure 6 and 7 The diagram in the image shows that embedding the switch die within the thickness of PCB 31 can further improve upon the above-mentioned reference. Figure 2-5 The proposed folded / symmetrical design and the field cancellation effect of parallel high / low current paths are described. Among other benefits, embedding can reduce the equivalent series inductance (ESL) to reduce voltage / current overshoot, ringing, and electromagnetic interference within the power module 30. Embedding the first and second power switch groups 32H and 32L can also reduce manufacturing steps by utilizing an embedded PCB manufacturing process.

[0050] and Figure 3 The surface mount solution is as follows, wherein the corresponding first and second power switch groups 32H and 32L are mounted on the positive busbar 34 on the opposite first and second sides 31-1 and 31-2 of the PCB 31. + and negative busbar 34 -, Figure 6 (i.e., power module 30A) and Figure 7 The topology of (i.e., power module 30B) includes a gap 42 defined by PCB 31 between the first and second power switch groups 32H and 32L. FR-4 or other construction material of PCB 31 is used to fill this gap. Figure 6 Gap 42 in the embodiment.

[0051] and Figure 6 The power module 30A is relatively, Figure 7 The PCB 31 of the power module 30B defines an elongated cooling channel 42C that extends between and is parallel to the respective planes of the second power switch 32L and the first power switch group 32H to aid in their dual-sided cooling. In this configuration, the elongated cooling channel 32C is filled with a thermally conductive material.

[0052] The higher power density enabled by the folded / dual-sided design described in this paper may lead to elevated temperatures approaching those of the first and second power switch groups 32H and 32L. Therefore, Figure 7 The power module 30B fills the gap 42 with a suitable thermally conductive material 44 of a different composition than that of the PCB 31. The presence of the thermally conductive material 44 helps optimize the dissipation of heat generated from high-speed switching and enables localized cooling of the first / high-side power switch group 32H and the second / low-side power switch group 32L during operation. The construction material of the thermally conductive material 44 can vary depending on the application, the available space in the gap 42, the expected temperature and thermal gradient, and other factors. Representative configurations of the thermally conductive material 44 include, for example, conductive pads of copper or other materials with low thermal resistance paths, micro heat pipes operable to conduct heat to an external heat sink (not shown), phase change materials (PCMs), ceramic-embedded epoxy materials, graphite or graphene layers, etc.

[0053] refer to Figure 8 As shown in the reference above Figure 4A and Figure 4B It is noted that it is desirable to place the gate driver IC 40 close to the corresponding first and second power switch groups 32H and 32L, which are controlled solid-state switches. Since the loop size is proportional to the linear distance between the gate driver IC 40 and the chip on which the first and second power switch groups 32H and 32L are disposed, it is preferable to minimize the loop size as much as possible. Proximity placement helps reduce gate loop resistance and parasitic inductance, and also improves power density compared to a topology that extends traces between the controlled switches and the gate driver IC 40. Therefore, Figure 8 The placement complements the benefits of the folded / double-sided and symmetrical configuration of PCB 31.

[0054] exist Figure 8In the configuration shown, power module 30C is replaced by high-side gate driver IC 40H and low-side gate driver IC 40L. Figure 4A The gate driver ICs 40 together form the internal gate driver circuitry within the power module 30C. In this implementation, the first power switch group 32H is separated from the first side 30-1 of the PCB 31 via a first gap 48-1 containing the high-side gate driver IC 40H. Similarly, the second power switch group 32L is separated from the second side 30-2 of the PCB 31 via a second gap 48-2 containing the low-side gate driver IC 40L. Separated gate-source loop traces 46 extend between the high-side gate driver IC 40H and the low-side gate driver IC 40L, and the corresponding first / high-side power switch group 32H and second / low-side power switch group 32L.

[0055] exist Figure 8 In the power module 30C illustrated in the figure, according to this disclosure, the overlap characteristic of the gate-source loop trace 46 further contributes to reducing loop inductance. Optionally, the high-side gate driver IC 40H and the low-side gate driver IC 40L can be shielded with a thin copper plate 48, which can be applied to the first side 31-1 and the second side 31-2 within the first and second gaps. Such a configuration can be used to further reduce electromagnetic interference.

[0056] like Figure 1-8 The disclosed technical solutions illustrated in the diagram and above are operable to reduce voltage / current overshoot, thereby reducing device stress in power module 30 and its variations, namely power modules 300, 30A, 30B, and 30C, including positive and negative busbars 34. + and 34 - And decoupling capacitor 29. The proposed circuit topology enables the use of smaller capacitor 29 and bus 34 compared to competing architectures. - and 34 + This is coupled with the use of switching dies with lower rated voltages. Among other benefits, the power module 30 in its various configurations helps reduce ringing, radiated / conducted electromagnetic interference, achieve higher switching speeds, and improve heat dissipation. These and other accompanying benefits of the foregoing disclosure will now be readily apparent to those skilled in the art who will benefit from this disclosure.

[0057] For the purposes of this specification, unless otherwise stated, the use of the singular includes the plural, and vice versa; the terms “and” and “or” should be used both as conjunctions and disjunctive words; and the words “including,” “containing,” “comprising,” “having,” and the like should mean “included without limitation.” Furthermore, approximate words such as “about,” “almost,” “substantially,” “generally,” “approximately,” etc., may be used herein in the sense of “being, near, or almost being” or “within 0-5% of,” or “within acceptable manufacturing tolerances,” or logical combinations thereof.

[0058] The detailed description and accompanying drawings are supporting and descriptive of this teaching, but the scope of this teaching is defined only by the claims. While some best practices and other examples for carrying out this teaching have been described in detail, various alternative designs and aspects exist to practice the teaching as defined in the appended claims.

Claims

1. A power module, comprising: Switch output node (SW); The local voltage bus has a positive bus and a negative bus arranged on corresponding parallel planes, which are respectively connected to the positive input node (HV). + ) and negative input node (HV) - ); A printed circuit board (PCB) is positioned between the positive and negative busbars; The first power switch group is connected to the positive bus adjacent to the first side of the PCB. The first power switch group is at the positive input node (HV). + There is a first / high-side current path between the switch output node (SW) and the switch output node (SW); The second power switch group is connected to the negative bus adjacent to the second side of the PCB. The second power switch group is at the negative input node (HV). - There is a second / low-side current path between the switch output node (SW) and the switch output node (SW); and Multiple decoupling capacitors are connected to the positive and negative buses, and the local voltage bus is located between the first / high-side current path and the second / low-side current path.

2. The power module according to claim 1, wherein, The first power switch and the second power switch group are surface mounted to the first side and the second side of the PCB, respectively.

3. The power module according to claim 1, wherein, The first power switch group and the second power switch group are configured as metal-oxide-semiconductor field-effect transistors (MOSFETs).

4. The power module according to claim 1, wherein, Multiple decoupling capacitors include at least six decoupling capacitors.

5. The power module according to claim 4, wherein, At least six decoupling capacitors, including twenty-four decoupling capacitors, are included, and the power module is configured as a three-phase multilevel converter.

6. The power module according to claim 1, further comprising: One or more current sensors are mounted on the PCB.

7. The power module according to claim 6, wherein, One or more current sensors include one or more shunt resistors.

8. The power module according to claim 1, further comprising: The gate driver integrated circuit (IC) is connected to the PCB, close to the first power switch group and the second power switch group.

9. The power module according to claim 8, wherein, Gate driver ICs include: High-side gate driver integrated circuits (ICs); and Low-side gate driver IC, wherein: The first power switch group is separated from the first side of the PCB by a first gap, in which a high-side gate driver IC is contained; and The second power switch group is separated from the second side of the PCB by a second gap, in which the low-side gate driver IC is contained.

10. The power module according to claim 1, wherein, The first and second power switch groups are embedded in the PCB.

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