Bus bar and capacitor for traction inverter

Abstract

The invention provides a bus bar and a capacitor for a traction inverter. Systems and methods for constructing a traction inverter for a vehicle are described. The traction inverter includes a positive bus bar and a negative bus bar coupled to a capacitor and to a plurality of switches. The capacitor is formed of a plurality of individual capacitors stacked together.

Description

Technical Field

[0001] The present specification relates to methods and systems for building a traction inverter including capacitors and bus bars for an electric or hybrid vehicle. The methods and systems may be particularly useful for vehicles including a lower voltage battery and a higher voltage traction battery. Background Art

[0002] An electric vehicle or hybrid vehicle may include an inverter that can convert the direct current (DC) output of the traction battery into alternating current (AC) to power the traction motor. The inverter may also convert AC power to DC power during periods when the kinetic energy of the vehicle is converted into electrical energy to slow the vehicle. The inverter may include transistors that operate as switches to convert DC to AC and vice versa. The inverter may also include capacitors that filter the power exchanged between the traction battery and the switch. The capacitance of the capacitor and the power requirements of the capacitor may cause the bus positive and negative bus bars to be separated between the positive and negative terminals of the capacitor. The separation of the bus bars may increase the stray inductance of the inverter circuit. The inductance may cause voltage spikes within the inverter, which the power card including the transistors and other components must tolerate. Therefore, the power card may be designed with components that tolerate voltage spikes but increase the financial cost of the power card. Summary of the invention

[0003] Currently, inverters may include a capacitor assembly that is physically separated from the power module assembly of the inverter (e.g., a switching power transistor that transfers power between the DC and AC power supplies). The physical separation can be overcome via positive (+) and negative (-) bus bars, which allow power to be transferred between the capacitor and the power module assembly. However, the positive and negative terminals of the capacitor may be separated by a considerable distance, and this distance causes a separation between the positive and negative bus bars. The separation between the positive and negative bus bars may increase the bus bar resistance, increase the bus bar temperature, and increase the stray inductance. In addition, a larger bus bar that spans the distance between the positive and negative terminals of the capacitor may result in a cantilever load, which may make it more difficult for the inverter assembly to meet vibration specifications. Larger bus bars may also increase the packaging size and inverter mass, which may be undesirable.

[0004] The inventors of this article have recognized the above-mentioned problems and have developed a traction inverter, which includes: a plurality of stacked capacitors, each of the plurality of stacked capacitors including a positive lead and a negative lead; a first bus bar, the first bus bar including through-slots for the positive lead and the negative lead of each of the plurality of stacked capacitors; and a second bus bar, the second bus bar including through-slots only for the positive lead or only for the negative lead of each of the plurality of stacked capacitors.

[0005] By stacking capacitors and passing capacitor leads through at least one bus bar, a technical result of reducing inverter stray inductance and resistance can be provided. In addition, the volume, mass and cost of the inverter can be reduced. In particular, stacked capacitors arranged in parallel can provide a desired capacitance, and the bus bars can be close to each other to reduce the stray inductance between the bus bars. In addition, the power card can be directly fixed to one of the bus bars, so that the surface area and mass of the bus bar can be reduced.

[0006] The present description may provide several advantages. In particular, the method may reduce the stray inductance between the positive busbar and the negative busbar, allowing the use of power modules with lower rated voltages. Furthermore, the method may reduce the financial expense and mass of the traction inverter, allowing the vibration durability to be increased. Additionally, the lower inductance may allow the inverter to switch at higher speeds and incur fewer losses.

[0007] The above advantages and other advantages and features of the present specification will be readily apparent from the following detailed description when taken alone or in conjunction with the accompanying drawings.

[0008] It will be appreciated that the above summary is provided to introduce in simplified form a series of concepts further described in the detailed description. This is not meant to identify the key features of the claimed subject matter, the scope of which is uniquely defined by the claims attached to the detailed description. Furthermore, the claimed subject matter is not limited to implementations that address any disadvantages mentioned above or in any part of this disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Advantages described herein will be more fully understood by reading examples of embodiments referred to herein as detailed descriptions when read alone or with reference to the accompanying drawings, in which:

[0010] Figure 1 is a schematic diagram of an example electric vehicle.

[0011] Figure 2 is a schematic diagram of an example inverter.

[0012] Figures 3 to 6An inverter capacitor and bus bar according to the present description are shown.

[0013] Figure 7 A flow chart of a method for constructing an inverter is shown. DETAILED DESCRIPTION

[0014] The present specification relates to building an inverter for an electric traction machine. The inverter includes a capacitor and bus bar arrangement that can reduce inductance so that a lower capacity power card can be included in the inverter. The inverter can be included in a Figure 1 The inverter may be an electric vehicle as shown in FIG. 1 or alternatively a hybrid vehicle. Figure 2 The inverter may include capacitors and bus bars, such as Figures 3 to 6 As shown. Figure 7 Method to produce capacitors and bus bars.

[0015] In addition to the schematically depicted components, Figures 3 to 6 However, in alternative embodiments, the inverter assembly may have other relative component dimensions.

[0016] Figure 1 1 is a block diagram of a vehicle 121 including a powertrain or driveline 100. A front portion of the vehicle 121 is indicated at 110, and a rear portion of the vehicle 121 is indicated at 111. The driveline 100 includes an electric machine 126. The electric machine 126 may consume or generate electric power depending on its operating mode. Figure 1 , the mechanical connections between the various components are shown as solid lines, while the electrical connections between the various components are shown as dotted lines.

[0017] The transmission system 100 has a rear axle 122. In some examples, the rear axle 122 may include two half shafts, for example, a first half shaft 122a and a second half shaft 122b. The transmission system 100 also includes front wheels 130 and rear wheels 131. The rear wheels 131 may be driven via the motor 126.

[0018] The rear axle 122 is coupled to the motor 126. The rear drive unit 136 can transfer power from the motor 126 to the axle 122, thereby rotating the rear wheels 131. The rear drive unit 136 can include a low gear 175 and a high gear 177 coupled to the motor 126 via an output shaft 126o of the motor 126. The low gear 175 can be engaged via a fully closed low gear clutch 176. The high gear 177 can be engaged via a fully closed high gear clutch 178. The high gear clutch 178 and the low gear clutch 176 can be opened and closed via commands received by the rear drive unit 136 via a controller area network (CAN) 199. Alternatively, the high gear clutch 178 and the low gear clutch 176 can be opened and closed via a digital output or pulse width provided by the control system 114. The rear drive unit 136 can include a differential 128 so that torque can be provided to the first half shaft 122a and the second half shaft 122b. In some examples, an electronically controlled differential clutch (not shown) may be included in rear drive unit 136 .

[0019] The motor 126 can receive power from an onboard electrical energy storage device 132. In addition, the motor 126 can provide a generator function to convert the kinetic energy of the vehicle into electrical energy, where the electrical energy can be stored at the electrical energy storage device 132 to be used later by the motor 126. The inverter 134 can convert the alternating current generated by the motor 126 into direct current for storage at the electrical energy storage device 132, and vice versa. The electric drive system 135 includes the motor 126 and the inverter 134. The electrical energy storage device 132 can be a traction battery (e.g., a battery that supplies electricity to propel the vehicle), a capacitor, an inductor, or other electrical energy storage device. The power flowing into the electric drive system 135 can be monitored via a current sensor 145 and a voltage sensor 146. The position and speed of the motor 126 can be monitored via a position sensor 147. The torque generated by the motor 126 can be monitored via a torque sensor 148.

[0020] In some examples, electrical energy storage device 132 can be configured to store electrical energy that can be supplied to other electrical loads resident on the vehicle (in addition to the motor), including cabin heating and air conditioning systems, engine starting systems, headlight systems, cabin audio and video systems, etc.

[0021] The control system 114 may communicate with the motor 126, the electrical energy storage device 132, etc. The control system 114 may receive sensory feedback information from the electric drive system 135, the electrical energy storage device 132, etc. In addition, the control system 114 may send control signals to the electric drive system 135, the electrical energy storage device 132, etc. in response to the sensory feedback. The control system 114 may receive an indication of an operator-requested output of the vehicle propulsion system from the human operator 102 or the autonomous controller. For example, the control system 114 may receive sensory feedback from a pedal position sensor 194 in communication with a pedal 192. The pedal 192 may schematically refer to a driver demand pedal. Similarly, the control system 114 may receive an indication of a vehicle deceleration requested by the operator via the human operator 102 or the autonomous controller. For example, the control system 114 may receive sensory feedback from a pedal position sensor 157 in communication with a vehicle deceleration pedal 156.

[0022] The electrical energy storage device 132 may periodically receive electrical energy from a power source residing external to the vehicle (e.g., not part of the vehicle), such as a stationary power grid (not shown). As a non-limiting example, the powertrain 100 may be configured as a plug-in electric vehicle (EV), whereby electrical energy may be supplied to the electrical energy storage device 132 via a power grid (not shown).

[0023] The energy storage device 132 includes an energy storage device controller 139 and a power distribution module 138. The energy storage device controller 139 can provide charge balancing between energy storage elements (e.g., battery cells) and communication with other vehicle controllers (e.g., controller 112). The power distribution module 138 controls the flow of power into and out of the energy storage device 132.

[0024] One or more wheel speed sensors (WSS) 195 may be coupled to one or more wheels of the powertrain 100. The wheel speed sensors may detect the rotational speed of each wheel. Such an example of a WSS may include a permanent magnet type sensor.

[0025] The controller 112 may include a portion of a control system 114. In some examples, the controller 112 may be a single controller for the vehicle. The control system 114 is shown as receiving information from a plurality of sensors 116 (various examples of which are described herein) and sending control signals to a plurality of actuators 181 (various examples of which are described herein). As an example, the sensors 116 may include tire pressure sensors (not shown), wheel speed sensors 195, etc. In some examples, sensors associated with the motor 126, the wheel speed sensors 195, etc. may transmit information about various states of motor operation to the controller 112. The controller 112 includes a non-transitory (e.g., read-only memory) 165, a random access memory 166, a digital input / output 168, and a microcontroller 167. The controller 112 may receive input data via a CAN 199 and provide the data to a human / machine interface 140.

[0026] Reference now Figure 2 , the inverter 134 is shown as being electrically coupled to the energy storage device 132 (e.g., a battery). In this example, the energy storage device includes a plurality of battery cells 232 connected in series to increase the voltage of the energy storage device 132. The inverter 134 is also shown as being electrically coupled to the motor 126 (e.g., a three-phase motor that can operate as a motor or an alternator). The inverter 134 includes a controller 202 that can communicate with the motor 126 via a controller area network (CAN) 199. Figure 1 Controller 202 is electrically coupled to the bases of transistors 206, 208, and 210 to 215. Controller 202 can supply control signals to independently activate and deactivate transistors 206, 208, and 210 to 215. Controller 202 includes input and output 202a (e.g., digital input, digital output, analog input, analog output), memory 202b (e.g., read-only memory, electrically erasable memory, temporary memory RAM), and processor 202c. Controller 202 can sense the voltage at node 203 and sense the current through inductor 204 via current sensor 299.

[0027] Transistors 206, 208, and 210 to 215 are shown as insulated gate bipolar transistors (IGBTs), but in alternative configurations, they may be metal oxide field effect transistors (MOSFETs), field effect transistors (FETs), or other known types of transistors. Controller 202 may activate the IGBTs via supplying a higher potential voltage to the gates of transistors 206, 208, and 210 to 215. Controller 202 may deactivate the IGBTs via supplying a lower potential voltage to the gates of transistors 206, 208, and 210 to 215. The gates of transistors 206 and 208 are indicated by the letter "G". The collectors of transistors 206 and 208 are indicated by the letter "C". The emitters of transistors 206 and 208 are indicated by the letter "E". Transistors 210 to 215 have bases, emitters, and collectors similar to those indicated for transistors 206 and 208. Transistors 206 and 208 also include diodes 207 and 209 that are forward biased between the respective emitters and collectors. When transistors 206 and 208 are activated, current can flow between their collectors and emitters. When transistors 206 and 208 are deactivated, current flow between the collectors and emitters of transistors 206 and 208 is blocked. Transistors 210 to 215 operate similarly. Transistors 210 to 215 can be selectively activated and deactivated to convert DC to AC.

[0028] Inductor 204 is shown electrically coupled directly to transistors 206 and 208. Inductor 204 is also electrically coupled directly to capacitor 250, capacitor 252, and electrical energy storage device 132. Capacitor 251 is shown electrically coupled to capacitor 250 and the negative side of electrical energy storage device 132.

[0029] In boost mode, the controller 202 may selectively activate a transistor 208, which may be referred to as a boost transistor, to charge the inductor 204 via the charge provided from the positive terminal 133a of the energy storage device 132. The inductor 204 resists current flow as it begins to store electrical energy in a magnetic field. When the boost transistor 208 is closed, the polarity of the left hand side of the inductor 204 is positive. When the boost transistor 208 is turned off, the current through the inductor 204 decreases and the magnetic field of the inductor begins to decrease. The polarity of the inductor 204 changes so that the right side of the inductor 204 has a positive polarity because the reduced magnetic field of the inductor supports continued current flow to the load. The voltage of the energy storage device 132 and the voltage developed across the inductor 204 are connected in series, thereby providing the voltage of the energy storage device 132 plus the voltage of the inductor 204 at the node 280. The voltage at node 280 is formed at node 201 minus a small voltage drop on diode 207, which is the output of the variable voltage controlled inverter boost circuit and the input to transistors 210 to 215 when the VVC is operated in boost mode because diode 207 is forward biased. Charge can be stored in capacitor 231 to smooth the output voltage of the boost circuit at node 201. The voltage at node 201 is a DC voltage. The variable voltage controlled inverter boost circuit may include capacitors 250 to 252, inductor 204, boost transistor 208, diode 209, diode 207, capacitor 231, and resistor 230. The voltage at node 201 is supplied to transistors 210 to 215, which are turned on and off to provide three-phase AC power to motor 126. Whenever boost transistor 208 is commanded to be activated, buck transistor 206 is commanded to be deactivated to prevent a short circuit between node 201 and node 281.

[0030] If motor 126 requests a small amount of power, the battery voltage minus the small voltage drop of inductor 204 and diode 207 may be supplied at node 201 by deactivating buck transistor 206 and boost transistor 208 .

[0031] In buck mode, charge is supplied to inductor 204 via motor 126. In particular, the three-phase AC output of the motor is converted to a DC voltage at node 201 by switching transistors 210 to 215 via controller 202. Inductor 204 is charged via activation of transistor 206, which may be referred to as a buck transistor. Inductor 204 resists current flow as it begins to store electrical energy in a magnetic field. When boost transistor 208 is closed, the polarity of the right-hand side of inductor 204 is positive. When buck transistor 206 is turned off, the current through inductor 204 decreases and the magnetic field of the inductor begins to decrease. The polarity of inductor 204 changes so that the left side of inductor 204 has a positive polarity because the reduced magnetic field of the inductor supports continued current flow to the load (e.g., electrical energy storage device 132). The amount of time that inductor 204 is allowed to charge is controlled so that the voltage developed across inductor 204 is less than the voltage output via motor 126. Diode 209 couples the right side of inductor 204 to node 281, which is coupled to negative battery terminal 133b. The voltage formed on inductor 204 is connected to positive terminal 133a of energy storage device 132. Charge from inductor 204 flows to terminal 133a so that the energy storage device can be charged. The voltage at node 203 is controlled by adjusting the amount of time that buck transistor 206 is activated (e.g., closed to allow current to flow through the transistor). Whenever buck transistor 206 is activated, boost transistor 208 is deactivated (e.g., disconnected to inhibit current from flowing through the transistor). Charge can be stored in capacitors 250 to 252 to smooth the output voltage of the buck circuit at node 203. The voltage at node 203 is a DC voltage. The variable voltage controlled inverter buck circuit can include capacitors 250 to 252, inductor 204, buck transistor 206, diode 209, capacitor 231 and resistor 230. The voltage at node 203 is the output voltage of the variable voltage controlled inverter buck circuit. The controller 202 can monitor the voltages at nodes 203 and 201. In addition, the controller 202 can adjust the duty cycle of the signals supplied to the boost transistor 208 and the buck transistor 206 in response to the voltages at nodes 203 and 201.

[0032] Reference now Figure 3, shows an assembly diagram of a capacitor block, busbars, and power card for inverter 134. Capacitor block 231, first insulator 302, first busbar 304, second insulator 306, and second busbar 308 can be fastened together via an adhesive. Alternatively, leads (not shown) of capacitor block 231 can be fastened (e.g., via welding, sintering, brazing, or brazing, all of which may be referred to herein as welding) to first busbar 304 and second busbar 308 to hold capacitor block 231, first insulator 302, first busbar 304, second insulator 306, and second busbar 308 together.

[0033] The vertical, longitudinal and lateral directions of the inverter assembly 300 are indicated at 350. The capacitor block 231 consists of a plurality of capacitors stacked on edge with their leads oriented in the vertical direction, as shown in FIG. Figure 5 In this example, the longitudinal dimension of the capacitor block 231 is greater than the lateral dimension and the vertical dimension of the capacitor block, so that the capacitor block 231 is in the form of a rectangle.

[0034] The inverter assembly 300 includes a capacitor block 231, a first insulator 302, a first bus bar 304, a second insulator 306, a second bus bar 308, and a power card 310. The first insulator 302 and the second insulator 306 may be made of FR-4 (e.g., composite glass reinforced epoxy resin) or other known insulators. The first bus bar 304 and the second bus bar 308 may be made of a double-layer copper material. The capacitor block 231 may be formed by stacking a plurality of thin film capacitors, such as Figure 5 shown.

[0035] The thickness of the inverter assembly 300 is measured in the vertical direction, as indicated at guide line 360. The length of the inverter assembly 300 is measured in the longitudinal direction, as indicated at guide line 362. The width of the inverter assembly 300 is measured in the lateral direction, as indicated at guide line 364.

[0036] In this example, first bus bar 304 is a positive polarity bus bar and second bus bar 308 is a negative polarity bus bar; however, in other examples, first bus bar 304 may be a negative polarity bus bar and second bus bar 308 may be a positive polarity bus bar. Figure 4 This is an exploded view of the inverter assembly 300.

[0037] Reference now Figure 5 , shows a detailed exploded view of a portion of the inverter assembly 300. In the exploded view, the leads and through holes or slots are shown. Additionally, the size of the leads relative to the busbars is shown.

[0038] Figure 5Each adjacent capacitor 570 and 571 stacked to form a portion of a capacitor block 231 is shown. As shown at 506, the positive lead for the capacitor is indicated. As shown at 508, the negative lead for the capacitor is indicated. Each capacitor unit includes a single positive lead and a single negative lead. The vertical height (length) of the positive capacitor lead is indicated by guide line 522. The vertical height (length) of the negative capacitor lead is indicated by guide line 520. If the positions of the positive bus bar and the negative bus bar are swapped, the positive lead length may be greater than the negative lead length. The length of the negative lead is equal to or less than the thickness of the first insulator indicated at 518 plus the thickness of the positive bus bar indicated at 516, plus the thickness of the second insulator indicated at 514 and plus the thickness of the negative bus bar indicated at 512. The length of the negative lead is also greater than the thickness of the first insulator indicated at 518 plus the thickness of the positive bus bar indicated at 516. The length of the positive lead is less than the thickness of the first insulator indicated at 518 plus the thickness of the positive bus bar indicated at 516 .

[0039] The positive leads of adjacent capacitors are diagonally offset, as indicated by arrow 562. The lateral distance offset is indicated by guide line 560. Likewise, the negative leads of adjacent capacitors are diagonally offset, as indicated by arrow 564. The first bus bar 304 includes an insulator 550 in a through hole or slot 504 for the negative capacitor lead. The first bus bar 304 also includes a through hole or slot 502 for an uninsulated positive capacitor lead 506, as the positive capacitor lead 506 can be welded to the first bus bar 304. The second bus bar 308 includes a through hole or slot 510 only for an uninsulated negative capacitor lead 508, as the negative capacitor lead 508 can be welded to the second bus bar 308.

[0040] Figure 6 A cross-sectional view of the inverter assembly 300 is shown. The first capacitor unit 670 and the second capacitor unit 671 are shown adjacent to each other. The through holes for the first bus bar and the second bus bar permit the capacitor leads to be close together, thereby reducing stray inductance and resistive heating.

[0041] It can be noted that each capacitor unit can be stacked so that adjacent capacitor units share a common positive lead and adjacent capacitor units share a common negative lead. This allows reducing the actual total number of capacitor leads and omitting insulation between capacitor units.

[0042] therefore, Figures 1 to 6A traction inverter of the invention provides a traction inverter, the traction inverter comprising: a plurality of stacked capacitors, each of the plurality of stacked capacitors comprising a positive lead and a negative lead; a first bus bar, the first bus bar comprising a through slot for the positive lead and the negative lead of each of the plurality of stacked capacitors; and a second bus bar, the second bus bar comprising a through slot for only the positive lead of each of the plurality of stacked capacitors or only the negative lead. In a first example, the traction inverter further comprises a first insulator, the first insulator comprising a through slot for the positive lead and the negative lead of each of the plurality of stacked capacitors. In a second example that may include the first example, the traction inverter further comprises a second insulator, the second insulator comprising a through slot for only the positive lead of each of the plurality of stacked capacitors or only the negative lead. In a third example that may include one or both of the first and second examples, the traction inverter comprises: wherein the first insulator is positioned between the plurality of stacked capacitors and the first bus bar. In a third example, which may include one or both of the first and second examples, the traction inverter includes: wherein the second insulator is positioned between the first bus bar and the second bus bar. In a fifth example, which may include one or more of the first to fourth examples, the traction inverter further includes insulation within at least a portion of the through slot of the first bus bar. In a sixth example, which may include one or more of the first to fifth examples, the traction inverter further includes a plurality of power cards directly coupled to the second bus bar.

[0043] Figures 1 to 6The traction inverter assembly also provides a traction inverter, the traction inverter comprising: a plurality of stacked capacitors, the positive leads of two adjacent stacked capacitors in the plurality of stacked capacitors are diagonally offset from each other, and the negative leads of two adjacent stacked capacitors in the plurality of stacked capacitors are diagonally offset from each other; a first insulator, the first insulator comprising a slot through which the positive lead and the negative lead are configured to pass, the first insulator is in contact with the plurality of stacked capacitors; a first bus bar, the first bus bar comprising a through slot for the positive lead and the negative lead, the first bus bar is in contact with the first insulator; a second insulator, the second insulator comprising a slot through which only the positive lead or only the negative lead is configured to pass, the second insulator is in contact with the first bus bar; and a second bus bar, the second bus bar comprising a through slot for only the positive lead or only the negative lead, the second bus bar is in contact with the second insulator. In the first example, the traction inverter further comprises an insulator in a set of slots. In a second example that may include the first example, the traction inverter includes: wherein the insulator insulates the negative lead or the positive lead from the first bus bar. In a third example that may include one or both of the first and second examples, the traction inverter further includes a plurality of power cards in physical contact with the second bus bar. In a fourth example that may include one or more of the first to third examples, the traction inverter includes: wherein the plurality of power cards include one or more transistors (e.g., Figure 2 211).

[0044] In another representation, Figures 1 to 6 A traction inverter assembly provides a traction inverter, the traction inverter comprising: a plurality of stacked capacitors, each of the plurality of stacked capacitors comprising a positive lead and a negative lead; a first bus bar, the first bus bar comprising a through slot for the positive lead and the negative lead of each of the plurality of stacked capacitors; and a second bus bar, the second bus bar comprising a through slot for only the positive lead of each of the plurality of stacked capacitors or only the negative lead, and wherein each of the positive lead and the negative lead of the plurality of stacked capacitors has a length, the length being less than the thickness of the first bus bar plus the thickness of the second bus bar plus the thickness of a first insulator between the first bus bar and the second bus bar plus the thickness of an insulator between the plurality of stacked capacitors and the first bus bar.

[0045] Reference now Figure 7 , a method for constructing a traction inverter for supplying electrical power to an electric machine (e.g., a traction motor) is shown. Figure 7 The method may be part of an assembly process performed by humans and / or machines. Figure 7 The steps shown may be performed in the order recited or in an alternate order.

[0046] At 702, method 700 begins by assembling a traction inverter by stacking a plurality of individual capacitors, wherein each lead of each capacitor is oriented in the same direction (e.g., as Figure 5 The capacitors can be fastened together, or they can remain loosely stacked. Multiple capacitors can be stacked to form a rectangular block of capacitors, such as Figure 5 The block allows the size of the stacked capacitor to be minimized, thereby reducing stray inductance and resistance.

[0047] Method 700 proceeds to 704.

[0048] At 704, method 700 places a first insulator over one side of the capacitor block including the capacitor leads. The positive capacitor lead and the negative capacitor lead pass through the first insulator, such as Figure 6 The method 700 proceeds to 706 .

[0049] At 706, method 700 cuts a through hole or slot (eg, Figure 5 The through holes 502 and 504 of FIG. 504 are used to accommodate the positive and negative leads from each capacitor that makes up the capacitor block. The through holes used for one type of capacitor lead (e.g., the positive lead or the negative lead) can be larger than the through holes used for another type of capacitor lead (e.g., the positive lead or the negative lead). The through holes can be as shown in FIG. Figure 5 The arrangement shown is to reduce the space between the leads while maintaining isolation between the positive lead and the negative lead. Method 700 proceeds to 708 .

[0050] At 708, method 700 places the first bus bar over the first insulator so that the first insulator is sandwiched between the capacitor block and the first bus bar. The positive lead and the negative lead of each capacitor enter the slot or through hole cut in the first bus bar. Method 700 proceeds to 710.

[0051] At 710, if the first bus bar is a positive bus bar, a positive lead of the capacitor is welded to the first bus bar. If the first bus bar is a negative bus bar, a negative lead of the capacitor is welded to the first bus bar. The capacitor lead that is not welded to the first bus bar passes through the first bus bar. The capacitor lead that passes through the first bus bar is electrically isolated from the first bus bar via an insulator. Method 700 proceeds to 712.

[0052] At 712, method 700 places a second insulator over the first bus bar and the leads passing through the first bus bar. The capacitor leads also pass through the second insulator. The second insulator is in physical contact with the first bus bar such that the first bus bar is sandwiched between the first insulator and the second insulator, as shown in FIG. Figure 6Method 700 proceeds to 714 .

[0053] At 714, method 700 cuts a through hole or slot (eg, Figure 5 The through hole can be as shown in FIG. 510 to accommodate the positive lead or negative lead from each capacitor that makes up the capacitor block. Figure 5 The arrangement shown is to reduce the space between the leads while maintaining isolation between the positive lead and the negative lead. Method 700 proceeds to 716 .

[0054] At 716, method 700 places a second bus bar over the second insulator so that the second insulator is sandwiched between the first bus bar and the second bus bar. The positive lead or the negative lead of each capacitor enters a slot or through hole cut in the second bus bar. The second bus bar has half of the through holes of the first bus bar for capacitor leads. Method 700 proceeds to 718.

[0055] At 718, if the second bus bar is a positive bus bar, the positive lead of the capacitor is welded to the second bus bar. If the second bus bar is a negative bus bar, the negative lead of the capacitor is welded to the second bus bar. Each capacitor of the capacitor block is electrically coupled to the negative bus bar and the positive bus bar. Method 700 proceeds to 720.

[0056] At 720, method 700 solders the power card to the second bus bar. The power card can be soldered to the second bus bar, such as Figure 6 Method 700 proceeds to exit.

[0057] therefore, Figure 7A method for a traction inverter is provided, the method comprising: assembling a plurality of capacitors into a stack; placing a first insulator in contact with the stack; placing a first busbar in contact with the first insulator; placing a second insulator in contact with the first busbar; placing the second busbar in contact with the second insulator; and placing a plurality of power cards in contact with the second busbar. In a first example, the method comprises: wherein placing the first insulator in contact with the stack comprises placing a plurality of capacitor leads through the first insulator. In a second example that may include the first example, the method comprises: wherein placing the first busbar in contact with the first insulator comprises placing a plurality of capacitor leads through the first busbar. In a third example that may include one or both of the first and second examples, the method comprises: wherein placing the second insulator in contact with the first busbar comprises placing a group of a plurality of capacitor leads through the second insulator. In a fourth example that may include one or more of the first to third examples, the method comprises: wherein placing the second busbar in contact with the second insulator comprises placing the group of a plurality of capacitor leads through the second busbar. In a fifth example, which may include one or more of the first to fourth examples, the method further includes welding a plurality of leads from a plurality of capacitors to the first bus bar. In a sixth example, which may include one or more of the first to fifth examples, the method further includes welding a plurality of leads from a plurality of capacitors to the second bus bar. In a seventh example, which may include one or more of the first to sixth examples, the method includes: wherein the first bus bar includes a length substantially equal to a length of the second bus bar.

[0058] Figures 1 to 6The method also provides a traction inverter, the traction inverter comprising: a plurality of stacked capacitors, the positive leads of two adjacent stacked capacitors in the plurality of stacked capacitors being diagonally offset from each other, and the negative leads of two adjacent stacked capacitors in the plurality of stacked capacitors being diagonally offset from each other; a first insulator, the first insulator comprising slots through which the positive lead and the negative lead are configured to pass, the first insulator being in contact with the plurality of stacked capacitors; a first bus bar, the first bus bar comprising through slots for the positive lead and the negative lead, the first bus bar being in contact with the first insulator; a second insulator, the second insulator comprising slots through which only the positive lead or only the negative lead is configured to pass, the second insulator being in contact with the first bus bar; and a second bus bar, the second bus bar comprising through slots for only the positive lead or only the negative lead, the second bus bar being in contact with the second insulator. In the first example, the traction inverter further comprises an insulator in a set of slots. In a second example that may include the first example, the traction inverter includes: wherein an insulator insulates a negative lead or a positive lead from a first bus bar. In a third example that may include one or both of the first and second examples, the traction inverter further includes a plurality of power cards in physical contact with the second bus bar. In a fourth example that may include one or more of the first to third examples, the traction inverter includes: wherein a power card includes one or more transistors.

[0059] The manufacturing methods and routines disclosed herein can be stored as executable instructions in a non-transitory memory and can be performed by a manufacturing system including a controller in combination with various sensors and actuators. In addition, parts of the method can be physical actions taken in the real world to change the state of the device. The specific routines described herein can represent one or more of any number of processing strategies (such as event-driven, interrupt-driven, multi-tasking, multi-threading, etc.). To this end, the various actions, operations and / or functions shown can be executed in the order shown, executed in parallel, or omitted in some cases. Similarly, the processing order is not necessarily required to achieve the features and advantages of the examples described herein, but is provided for ease of illustration and description. One or more of the actions, operations and / or functions shown can be repeatedly performed according to the specific strategy used. In addition, the described actions, operations and / or functions can graphically represent the code in the non-transitory memory of the computer-readable storage medium that will be programmed into the system, wherein the described actions are implemented by executing instructions in a system including various hardware components in combination with an electronic controller. If necessary, one or more of the method steps described herein can be omitted.

[0060] Although various embodiments have been described above, it is understood that these embodiments are presented by way of example rather than limitation or constraint. It should be understood that the configurations and routines disclosed herein are exemplary in nature, and these specific examples should not be considered to have limiting meanings, because numerous variations are possible. For example, the above-mentioned technology can be applied to a powertrain system including different types of propulsion sources, and the different types of propulsion sources include different types of motors, internal combustion engines and / or transmissions. The technology can be used independently or in combination with other powertrain systems, as an example, the other powertrain systems are not limited to machinery and propulsion systems for dual axles, electric support axles, P4 axles, HEVs, BEVs, agriculture, ships, motorcycles, recreational vehicles, and highway and off-road vehicles. The subject matter of the present disclosure includes all novel and non-obvious combinations and sub-combinations of various systems and configurations disclosed herein and other features, functions and / or properties. It will be apparent to those skilled in the relevant art that the disclosed subject matter can be embodied in other specific forms without departing from the spirit of the subject matter.

[0061] The appended claims particularly point out certain combinations and subcombinations regarded as novel and non-obvious. These claims may refer to "an" element or "a first" element or the equivalent thereof. Such claims may be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and subcombinations of the disclosed features, functions, elements, and / or properties may be claimed by amendment of the present claims or by presentation of new claims in this or a related application. Such claims, whether broader, narrower, equal, or different in scope to the original claims, are also deemed to be included in the subject matter of the present disclosure.

[0062] As used herein, unless otherwise specified, the term "about" is interpreted to mean ±5% of the stated range.

[0063] According to the present invention, a traction inverter is provided, which has: a plurality of stacked capacitors, each of the plurality of stacked capacitors including a positive lead and a negative lead; a first bus bar, the first bus bar including a through slot for the positive lead and the negative lead of each of the plurality of stacked capacitors; and a second bus bar, the second bus bar including a through slot only for the positive lead or only for the negative lead of each of the plurality of stacked capacitors.

[0064] According to an embodiment, the invention is also characterized by a first insulator including through slots for the positive lead and the negative lead of each of the plurality of stacked capacitors.

[0065] According to an embodiment, the present invention is also characterized by a second insulator including a through slot only for the positive lead or only for the negative lead of each of the plurality of stacked capacitors.

[0066] According to an embodiment, the first insulator is positioned between the plurality of stacked capacitors and the first bus bar.

[0067] According to an embodiment, the second insulator is positioned between the first bus bar and the second bus bar.

[0068] According to an embodiment, the invention is also characterized by insulation within at least a portion of the through slot of the first bus bar.

[0069] According to an embodiment, the invention also features a plurality of power cards coupled directly to the second bus bar.

[0070] According to the present invention, a method for a traction inverter includes: assembling a plurality of capacitors into a stack; placing a first insulator in contact with the stack; placing a first bus bar in contact with the first insulator; placing a second insulator in contact with the first bus bar; placing a second bus bar in contact with the second insulator; and placing a plurality of power cards in contact with the second bus bar.

[0071] In one aspect of the invention, placing the first insulator in contact with the stack includes placing a plurality of capacitor leads through the first insulator.

[0072] In one aspect of the invention, placing the first bus bar in contact with the first insulator includes placing the plurality of capacitor leads through the first bus bar.

[0073] In one aspect of the invention, placing the second insulator in contact with the first bus bar includes placing a group of the plurality of capacitor leads through the second insulator.

[0074] In one aspect of the invention, placing the second bus bar in contact with the second insulator includes placing the set of the plurality of capacitor leads through the second bus bar.

[0075] In one aspect of the invention, the method further comprises welding a plurality of leads from the plurality of capacitors to the first bus bar.

[0076] In one aspect of the invention, the method includes welding a plurality of leads from the plurality of capacitors to the second bus bar.

[0077] In one aspect of the invention, the first bus bar comprises a length substantially equal to a length of the second bus bar.

[0078] According to the present invention, a traction inverter is provided, which has: a plurality of stacked capacitors, the positive leads of two adjacent stacked capacitors among the plurality of stacked capacitors are diagonally offset from each other, and the negative leads of the two adjacent stacked capacitors among the plurality of stacked capacitors are diagonally offset from each other; a first insulator, the first insulator including a slot through which the positive lead and the negative lead are configured to pass, the first insulator being in contact with the plurality of stacked capacitors; a first bus bar, the first bus bar including a through slot for the positive lead and the negative lead, the first bus bar being in contact with the first insulator; a second insulator, the second insulator including a slot through which only the positive lead or only the negative lead is configured to pass, the second insulator being in contact with the first bus bar; and a second bus bar, the second bus bar including a through slot only for the positive lead or only for the negative lead, the second bus bar being in contact with the second insulator.

[0079] According to an embodiment, the invention also features an insulator in one set of said slots.

[0080] According to an embodiment, the insulator insulates the negative electrode lead or the positive electrode lead from the first bus bar.

[0081] According to an embodiment, the invention also features a plurality of power cards in physical contact with the second bus bar.

[0082] According to an embodiment, the plurality of power cards comprises one or more transistors.

Claims

1. A traction inverter, comprising: a plurality of stacked capacitors, each of the plurality of stacked capacitors comprising a positive lead and a negative lead; a first bus bar including through slots for the positive lead and the negative lead of each of the plurality of stacked capacitors; as well as A second bus bar includes a through slot for only the positive lead or only the negative lead of each of the plurality of stacked capacitors.

2. The traction inverter of claim 1, further comprising a first insulator including through slots for the positive lead and the negative lead of each of the plurality of stacked capacitors.

3. The traction inverter of claim 2, further comprising a second insulator including a through slot only for the positive lead or only for the negative lead of each of the plurality of stacked capacitors. 4 . The traction inverter of claim 3 , wherein the first insulator is positioned between the plurality of stacked capacitors and the first bus bar. 5 . The traction inverter of claim 4 , wherein the second insulator is positioned between the first bus bar and the second bus bar.

6. The traction inverter of claim 5, further comprising insulation within at least a portion of the through slot of the first bus bar.

7. The traction inverter of claim 6, further comprising a plurality of power cards directly coupled to the second bus bar.

8. A method for a traction inverter, the method comprising: Assembling multiple capacitors into a stack; placing a first insulator in contact with the stack; placing a first bus bar in contact with the first insulator; placing a second insulator in contact with the first bus bar; placing a second bus bar in contact with the second insulator; as well as A plurality of power cards are placed in contact with the second bus bar.

9. The method of claim 8, wherein placing the first insulator in contact with the stack comprises placing a plurality of capacitor leads through the first insulator.

10. The method of claim 9, wherein placing the first bus bar in contact with the first insulator comprises placing the plurality of capacitor leads through the first bus bar.

11. The method of claim 10, wherein placing the second insulator in contact with the first bus bar comprises placing a group of the plurality of capacitor leads through the second insulator.

12. The method of claim 11, wherein placing the second bus bar in contact with the second insulator comprises placing the set of the plurality of capacitor leads through the second bus bar.

13. The method of claim 8, further comprising welding a plurality of leads from the plurality of capacitors to the first bus bar.

14. The method of claim 8, further comprising welding a plurality of leads from the plurality of capacitors to the second bus bar.

15. The method of claim 8, wherein the first bus bar comprises a length substantially equal to a length of the second bus bar.

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