WO2017054687A1 - 一种汽车用的电驱动系统及使用了该电驱动系统的汽车 - Google Patents

一种汽车用的电驱动系统及使用了该电驱动系统的汽车 Download PDF

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Publication number
WO2017054687A1
WO2017054687A1 PCT/CN2016/100068 CN2016100068W WO2017054687A1 WO 2017054687 A1 WO2017054687 A1 WO 2017054687A1 CN 2016100068 W CN2016100068 W CN 2016100068W WO 2017054687 A1 WO2017054687 A1 WO 2017054687A1
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WO
WIPO (PCT)
Prior art keywords
unit
inverter
drive system
electric drive
motor
Prior art date
Application number
PCT/CN2016/100068
Other languages
English (en)
French (fr)
Inventor
柴旭
黄晨东
何彬
兰红玉
刘梦洋
任谊滨
梁博之
柴少彪
Original Assignee
蔚来汽车有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 蔚来汽车有限公司 filed Critical 蔚来汽车有限公司
Priority to EP16850311.8A priority Critical patent/EP3357727A4/en
Priority to US15/764,060 priority patent/US10988013B2/en
Publication of WO2017054687A1 publication Critical patent/WO2017054687A1/zh

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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02KDYNAMO-ELECTRIC MACHINES
    • H02K11/00Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection
    • H02K11/30Structural association with control circuits or drive circuits
    • H02K11/33Drive circuits, e.g. power electronics
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60KARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
    • B60K1/00Arrangement or mounting of electrical propulsion units
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60KARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
    • B60K17/00Arrangement or mounting of transmissions in vehicles
    • B60K17/04Arrangement or mounting of transmissions in vehicles characterised by arrangement, location, or kind of gearing
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02KDYNAMO-ELECTRIC MACHINES
    • H02K5/00Casings; Enclosures; Supports
    • H02K5/04Casings or enclosures characterised by the shape, form or construction thereof
    • H02K5/22Auxiliary parts of casings not covered by groups H02K5/06-H02K5/20, e.g. shaped to form connection boxes or terminal boxes
    • H02K5/225Terminal boxes or connection arrangements
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02KDYNAMO-ELECTRIC MACHINES
    • H02K7/00Arrangements for handling mechanical energy structurally associated with dynamo-electric machines, e.g. structural association with mechanical driving motors or auxiliary dynamo-electric machines
    • H02K7/003Couplings; Details of shafts
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02KDYNAMO-ELECTRIC MACHINES
    • H02K7/00Arrangements for handling mechanical energy structurally associated with dynamo-electric machines, e.g. structural association with mechanical driving motors or auxiliary dynamo-electric machines
    • H02K7/006Structural association of a motor or generator with the drive train of a motor vehicle
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02KDYNAMO-ELECTRIC MACHINES
    • H02K7/00Arrangements for handling mechanical energy structurally associated with dynamo-electric machines, e.g. structural association with mechanical driving motors or auxiliary dynamo-electric machines
    • H02K7/10Structural association with clutches, brakes, gears, pulleys or mechanical starters
    • H02K7/116Structural association with clutches, brakes, gears, pulleys or mechanical starters with gears
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60LPROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L2210/00Converter types
    • B60L2210/40DC to AC converters
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60LPROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L2220/00Electrical machine types; Structures or applications thereof
    • B60L2220/10Electrical machine types
    • B60L2220/12Induction machines
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60LPROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L2260/00Operating Modes
    • B60L2260/20Drive modes; Transition between modes
    • B60L2260/28Four wheel or all wheel drive
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60LPROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L50/00Electric propulsion with power supplied within the vehicle
    • B60L50/50Electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells
    • B60L50/51Electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells characterised by AC-motors
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02KDYNAMO-ELECTRIC MACHINES
    • H02K2211/00Specific aspects not provided for in the other groups of this subclass relating to measuring or protective devices or electric components
    • H02K2211/03Machines characterised by circuit boards, e.g. pcb
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02TCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00Road transport of goods or passengers
    • Y02T10/60Other road transportation technologies with climate change mitigation effect
    • Y02T10/64Electric machine technologies in electromobility
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02TCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00Road transport of goods or passengers
    • Y02T10/60Other road transportation technologies with climate change mitigation effect
    • Y02T10/70Energy storage systems for electromobility, e.g. batteries
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02TCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00Road transport of goods or passengers
    • Y02T10/60Other road transportation technologies with climate change mitigation effect
    • Y02T10/72Electric energy management in electromobility

Definitions

  • the present invention relates to an electric drive system for an automobile, and more particularly to a compact electric drive system for an electric vehicle or a hybrid vehicle using an electric motor as a power output source.
  • electric vehicles or hybrid vehicles use electric energy as a power source, compared with the traditional vehicles that use gasoline or diesel as a power source, they have significant advantages in reducing emissions and saving energy, so they are promoting green environmental protection today. The times are gradually becoming the declining trend of the development of the automobile industry.
  • an AC motor (hereinafter referred to simply as an electric motor) is generally used as a power output source based on cost, structural complexity, maintenance convenience, and work efficiency.
  • an energy storage system battery pack, etc.
  • the output thereof is direct current, so to drive the alternating current motor, it is necessary to configure an inverter between the energy storage system and the alternating current motor to apply direct current. Converted to AC power to the motor.
  • the motor operates with AC power supplied from the inverter as a power source, and its output shaft is connected to the gearbox, which is decelerated by the gearbox and supplied to the wheel for rotation.
  • Patent Document 1 discloses a horizontally arranged compact electric drive system in which an inverter, a gearbox, and a motor are linearly arranged side by side along the input shaft direction of the transmission, thereby reducing electric drive.
  • the longitudinal height of the system saves the longitudinal footprint of the electric drive system.
  • the electric drive system is integrated and packaged in one casing, which causes the electric drive system to fail to invert the inverter during production off-line testing or post-repair.
  • the tester, gearbox, and motor are tested, repaired, or replaced separately, resulting in increased testing and maintenance costs.
  • the present invention has been made in view of the above problems in the prior art, and an object thereof is to provide an electric drive system for an automobile which further shortens the lateral size. Further, it is another object of the present invention to provide an electric drive system for an automobile that is both compact and easy to test and repair. Further, it is still another object of the present invention to provide an electric drive system for an automobile which is provided with an insulation protection for improving electrical connection between an inverter unit and a motor unit. It should be noted that the above various objects are merely illustrative of the technical effects of the present invention, and it is not required that the present invention must achieve all of the above objects at the same time.
  • An electric drive system for an automobile includes: an inverter unit for converting externally supplied DC power into AC power; and a motor unit for converting AC power from the inverter unit into a machine Rotate and output from the output shaft; the gearbox unit decelerates the rotation transmitted from the input shaft and outputs it.
  • the motor unit, the gearbox unit, and the inverter unit respectively have relatively independent package housings, and the motor unit and the inverter unit are along the input shaft of the transmission unit
  • the axial direction of the gearbox unit is detachably fixed to each other.
  • the axial thickness of the package housing of the inverter unit is the smallest.
  • One or more inverter circuit boards may be included in the inverter unit, and the inverter circuit board is configured in such a manner that its circuit board surface is substantially perpendicular to the axial direction.
  • the package housing of the inverter unit may be a box shape in which a shape of a bottom surface matches a projected shape of an outer contour of each of the circuit boards inside.
  • a partition plate may be disposed in the gearbox unit to divide the gearbox unit into a gear transmission cavity and a dry cavity for inserting an electrical connection line between the motor unit and the inverter unit, the dry cavity
  • a docking region that interfaces the electrical unit with the electrical connection of the inverter unit may be included.
  • the electrical connection line can have multiple sets of connecting lines.
  • An insulating block may be provided in the docking area, and the insulating block may have an insulating grille that insulates between the sets of connecting lines of the electrical connecting line.
  • the electrical connection line can be a busbar.
  • the busbar of the motor unit and the busbar of the inverter unit may be stacked one above another in the docking area and connected to each other in a detachable connection manner.
  • the output shaft of the motor unit may be a hollow shaft having an internal spline, and the input shaft of the transmission unit is extended from a package housing of the transmission unit, and the front end has an external spline The axis.
  • the input shaft of the transmission unit is inserted into the output shaft of the motor unit, and the external spline is coupled with the inner spline of the output shaft of the motor unit such that the The input shaft of the transmission unit rotates with rotation of the output shaft of the motor unit.
  • Another aspect of the present invention is an automobile that employs an electric drive system for an automobile as described above as a front wheel drive system.
  • the automobile may also employ the same other electric drive system for the above-described automobile as the rear wheel drive system.
  • FIG. 1 is a view schematically showing an electric drive system and related system of an embodiment of the present invention disposed in an electric vehicle Figure.
  • FIG. 2 is a view showing an electric drive system according to an embodiment of the present invention, wherein (a) of FIG. 2 is a front view schematically showing an appearance of an electric drive system after assembly; (b) of FIG. 2 is a view schematically showing assembly. A longitudinal cross-sectional view of the rear electric drive system.
  • FIG. 3 is a view schematically showing the configuration of an insulating block and its mounting position in the embodiment of the present invention, and (a) and (b) of FIG. 3 are respectively for explaining the shift shown in (a) of FIG. 2.
  • FIG. 4 is a view for explaining a mounting manner of an inverter internal circuit PCB board disclosed in Patent Document 1 as a comparative example.
  • Fig. 5 is an exploded view schematically showing an assembly relationship of a motor unit, a transmission unit, and an inverter unit according to an embodiment of the present invention.
  • Fig. 1 is a view schematically showing an electric drive system and a related system of the present invention disposed in an electric vehicle.
  • an electric vehicle is taken as an example to show the arrangement of the electric drive system and its related system of the present invention, and the representation of other systems required for the electric vehicle is omitted.
  • an electric vehicle according to an embodiment of the present invention includes an electric drive system 10, a power control system 20, an energy storage system 30, a front wheel axle 40, and a rear wheel axle 50.
  • the electric drive system 10 includes an inverter unit 100, a transmission unit 200, and a motor unit 300 as an AC motor.
  • the inverter unit 100 is received from the energy storage system 30 (which may be an on-board energy storage or fuel cell power supply).
  • the DC power of the battery pack is converted into AC power to the motor unit 300 under the power control of the power control system 20, and the rotor in the motor unit 300 is rotated by the magnetic field generated by the AC power, thereby converting the electric energy into
  • the mechanical rotational force outputs the rotational force to the transmission unit 200 through the output shaft, and the transmission unit 200 decelerates the rotation by the cooperation of the gear mechanisms inside thereof, and after being adjusted by the differential gear, outputs to the half of the wheel.
  • the shaft front wheel half shaft 40, rear wheel half shaft 50 drives the wheel to rotate.
  • FIG. 2 is a view showing an electric drive system according to an embodiment of the present invention, wherein (a) of FIG. 2 is a front view schematically showing an appearance of an electric drive system after assembly; (b) of FIG. 2 is a view schematically showing assembly. A longitudinal cross-sectional view of the rear electric drive system.
  • the structural features of the electric drive system of the present embodiment will be specifically described below based on Fig. 2 .
  • the motor unit 300, the transmission unit 200, and the inverter unit 100 each have their own independent package housings, which respectively constitute relatively independent units.
  • the motor unit 300, the transmission unit 200, and the inverter unit 100 are laterally arranged in a line along the direction of the input shaft 202 of the transmission unit 200 (and also the direction of the output shaft 303 of the motor unit 300, hereinafter referred to simply as the axial direction). on.
  • the flange connection surface 309 on the output shaft side of the motor unit 300 and the flange connection surface of the motor side housing 210 of the transmission unit 200 are detachably connected by bolts, and the inverter side housing 211 of the transmission unit 200 Flange connection surface and flange connection surface 106 of the inverter unit 100 Removably connected by bolts.
  • the motor unit 300, the transmission unit 200, and the inverter unit 100 are connected by bolts to achieve a detachable mechanical connection, but a snap connection or a hinge may also be used. Other removable mechanical or non-mechanical connections, such as connections, may not be flanged as needed. Thereby, the motor unit 300, the transmission unit 200, and the inverter unit 100 can be easily attached and detached as a whole, which facilitates testing, maintenance, and maintenance of each unit.
  • each of the motor unit 300, the transmission unit 200, and the inverter unit 100 is schematically shown in (b) of FIG. 2 .
  • the illustration of the cooling system of each unit and the specific electronic circuit is omitted in FIG.
  • the motor unit 300 includes a stator 301 that is fixed to the casing, a rotor 302 that rotates based on a magnetic field generated when the stator 301 is energized, and an output shaft 303 that is fixed to the rotor 301 and integrally rotates.
  • Two sets of bearings 304 and 305 rotatably supporting the output shaft 303 and a bus bar 307 electrically connected to the stator 301 for supplying power to the motor unit 300 are respectively provided on both end sides of the output shaft 303.
  • the output shaft 303 has a hollow shaft structure, and an inner spline 306 for engaging an external spline of the input shaft of the transmission unit 200 is provided inside the hollow shaft.
  • the cavity surrounded by the motor side housing 210 and the inverter side housing 211 of the transmission unit 200 is divided by the internal partition 212 into the upper dry chamber 201 in the figure and The closed gear transmission chamber 213 in the lower part of the figure.
  • the dry chamber 201 is not filled with lubricating oil, and a busbar perforation for inserting the busbar 307 of the motor unit 300 is formed on the end surface of the dry chamber 201 on the side of the motor unit 300.
  • a groove structure opening upward in the drawing is formed, and the mating region 214 of the bus bar 307 of the motor unit 300 and the bus bar 105 of the inverter unit 100 is formed.
  • a busbar 105 for inserting the inverter unit 100 is formed in a region corresponding to the docking region 214 on a flange connection surface of the inverter-side housing 211 of the transmission unit 200 that is connected to the inverter unit 100.
  • the busbar is perforated.
  • an insulating block 209 is fixed in the docking region 214, and the bus bar 307 and the bus bar 105 inserted into the mating region 214 through the busbar perforations are vertically overlapped on the insulating block 209, and are passed through the bus bar 307 by bolts.
  • the bolt holes for the butting at the overlap of the bus bars 105 are screwed and fixed, so that the bus bar 307 of the motor unit 300 is electrically connected to the bus bar 105 of the inverter unit 100 and relatively fixed to the gearbox unit 200.
  • Inverter side housing 211 The specific configuration of the insulating block 209 will be described in detail later.
  • the gear transmission chamber 213 of the transmission unit 200 is provided with an input from the motor-side housing 210 of the transmission unit 200 to the outside, with an external spline input that cooperates with an internal spline of the output shaft of the motor unit 300.
  • Bearings 207a and 207b In the gear transmission chamber 213, lubricating oil is filled for lubricating the rotation of each gear set, and the input shaft 202 is removed from the lubricating oil to prevent leakage.
  • An oil seal member 216 is provided at a portion where the motor side housing 210 of the transmission unit 200 protrudes.
  • the gear transmission chamber of the transmission unit 200 is filled with lubricating oil, so that the function of the oil seal member 216 for preventing leakage of the lubricating oil is important.
  • the hollow shaft of the transmission unit 200 whose input shaft is an internal spline is used, the output shaft of the motor is inserted into the transmission unit 200 and spline-coupled, the oil seal member 216 may be subjected to a motor during a later test or repair process.
  • the spline output shaft is damaged or shortened by multiple insertions, extractions, and the like.
  • the motor unit 300 is not filled with lubricating oil or the like, and the oil seal member is not required.
  • the output shaft is a hollow spline hollow shaft structure, which can reduce the damage or shorten the life of the oil seal member of the transmission unit 200 during the later test or maintenance, and maintain the production of the oil seal member 216 and the input shaft 202. The level when going offline.
  • the transmission unit 200 has been described by taking a single-speed fixed-tooth ratio transmission as an example, but of course, a multi-speed transmission or the like may be employed.
  • FIG. 3 is a view schematically showing the configuration of the insulating block 209 and its mounting position. (a) and (b) of FIG. 3 are respectively for explaining the inverter-side housing 211 of the transmission unit 200 shown in (a) of FIG. 2 and the left side of the insulating block 209 fitted in the abutting region 214 thereof. View and top view.
  • a busbar 307 for the motor unit 300 and a busbar 105 of the inverter unit 100 are formed above the partition plate 212 of the inverter side casing 211 of the transmission unit 200.
  • the opening window 217 That is, the opening window 217 penetrates the inverter-side housing 211 of the transmission unit 200 in the axial direction.
  • the recessed space defined by the fenestration 217 and the partition 212 constitutes the mating area 214 of the busbar 307 of the motor unit 300 and the busbar 105 of the inverter unit 100.
  • An insulating block 209 is provided in the mating region 214, and the insulating block 209 is fixed to the inverter side casing 211 by bolting.
  • the insulating block 209 can be made of various inorganic, organic or hybrid insulating materials as long as it has the insulating properties required for the design.
  • the insulating block 209 is provided with an insulating grille 218 that extends upward in the direction in which the busbars are routed.
  • the motor unit 300 and the inverter unit 100 are respectively provided with three bus bars made of copper or other conductive materials, so that the insulating blocks 209 are provided with four insulating gratings 218, adjacent to each other. Between the insulating grids 218, a docking space is formed for the busbars 307 and the busbars 105 to overlap each other.
  • bolt holes 219 for screwing the bus bar 307 and the bus bar 105 are provided at each docking space.
  • the corresponding busbars 307 and the busbars 105 are overlapped in the corresponding docking space of the insulating block, and the bolt holes of the busbars are coaxial with the bolt holes of the docking space in the up and down direction. Align the ground, bolt through the aligned busbar 307, the busbar 105 and screw the bolt holes in the docking space so that the three are relatively fixed.
  • the bolt hole of the insulating block 209 may be a through hole, and a bolt blind hole is provided at a corresponding position of the inverter side housing 211 to pass the bolt through the aligned bus bar 307, the bus bar 105, and the docking space. After the bolt holes are screwed into the corresponding bolt blind holes of the inverter side housing 211, the bus bar 307, the bus bar 105, the insulating block 209, and the inverter side housing 211 are relatively fixed.
  • a busbar is also used between the inverter and the motor for electrical connection.
  • Each busbar is made of a conductive material of the order of 12 cm long, 2 cm wide and 0.5 cm thick to ensure its rigidity.
  • the insulating block 209 is further provided in the abutting region of the bus bar 307 of the motor unit 300 and the bus bar 105 of the inverter unit 100, the insulating grill 218 of the insulating block 209 can be used as The insulating members of each of the three sets of parallel-extending busbars function, and the docking space formed between the insulating grids 218 also functions as a supporting member for carrying the busbars.
  • the present invention can reduce the rigidity requirement of the busbar, save material cost, and at the same time effectively prevent the bolt for the butt busbar from being bumped due to long-term use. A short circuit occurs between the busbars when loosening, causing a major failure of the electric drive system.
  • connection method is not limited to the bolt connection, but may be a snap connection or a hinge.
  • Mechanical or non-mechanical connections such as connections and other removable means.
  • the inverter is a direct current/alternating current (DC/AC) power converter for converting the direct current power supplied from the energy storage system 30 into an alternating current power source required to drive the motor unit 300 (alternating current motor).
  • inverter unit 300 can be an active inverter, a passive inverter, and a plurality of different combinations of high performance DC/AC power converters.
  • FIG. 4 corresponds to Fig. 8 of Patent Document 1, showing the mounting manner of the internal circuit PCB of the inverter.
  • a broken line frame 400 schematically shows the outer casing of the inverter
  • reference numeral 401 denotes a mounting base of the inverter circuit PCB board
  • reference numeral 402 denotes an installation interface of the inverter circuit PCB board
  • reference numeral 403 denotes an inverse. Transformer circuit PCB board.
  • the inverter circuit has three PCB boards, and only one of the PCB boards 403 is shown in FIG.
  • the three PCB boards 403 are respectively inserted into the mounting interface 402 provided on the mounting base integrated with the gearbox, and the three PCB boards are arranged in a triangle shape.
  • the inverter circuit PCB board 403 in the inverter of Patent Document 1 is assembled in a direction parallel to the input shaft of the transmission (hereinafter referred to as an axial direction), after the inverter housing is externally mounted.
  • the axial length of the inverter must be greater than the axial length of the PCB board 403, causing the axial length of the inverter to be too long, thereby causing the overall axial length of the electric drive system to be too long.
  • the three PCB boards 403 are arranged in a triangle shape, and the inverter housing 400 has a cylindrical shape, and the useless space between the PCB board 403 and the outer casing 400 is too large, which causes waste of space and is not conducive to the PCB board. Construction of protective measures such as shock absorption.
  • the inverter unit of the embodiment of the present invention mainly includes two layers of inverter circuit PCB boards 101 and 102, and various electronic boards for implementing inverter functions are respectively mounted thereon. Components. Since the circuit configuration of the inverter and the DC/AC conversion principle and the like are not the invention of the present invention, various conventional inverter circuit principles and configurations can be employed, and thus detailed description thereof will be omitted.
  • the axial direction (hereinafter referred to as the axial direction) is arranged substantially perpendicularly, between the PCB board 101 of the flange connection face 106 of the inverter unit 100 and the housing of the inverter unit 100, and between the PCB boards.
  • the plurality of axially extending fixing posts 103 are fixed to each other, whereby the respective PCB boards are fixed in a laminated manner within the outer casing of the inverter unit 100.
  • the PCB boards may not be connected to each other, but may be respectively fixed to the housing of the inverter unit 100.
  • the housing of the inverter unit 100 is a box shape whose bottom surface shape matches the projected shape of the outer contour of each PCB board inside.
  • the shapes of the respective PCB boards 101 and 102 are quadrangular, the inverse
  • the outer casing of the transformer unit 100 is a casing having a rectangular parallelepiped shape.
  • the axial thickness of the inverter circuit PCB boards 101 and 102 assembled in a stacked manner is smaller than the length and width of the PCB board itself, so that the PCB boards and related components in the inverter unit 100 are arranged in this way.
  • the axial length of the inverter unit 100 can be shortened, thereby shortening the axial length of the entire electric drive system.
  • the outer casing of the inverter unit 100 has a box shape in which the shape of the bottom surface matches the projected shape of the outer contour of each PCB board inside, the internal space utilization of each PCB board and the outer casing is high, and is convenient. Build effective board protection measures.
  • FIG. 5 is an exploded view schematically showing an assembly relationship of the motor unit 300, the transmission unit 200, and the inverter unit 100 of the present embodiment.
  • the motor unit 300, the transmission unit 200, and the inverter unit 100 are arranged along the axial direction of the input shaft 202 of the transmission unit 200 (indicated by a one-dot chain line in the drawing), and the transmission unit 200
  • the input shaft 202 extends from the input shaft through hole of the motor side housing 210 and extends into the output shaft 303 of the motor unit 300 as a hollow shaft, the external spline of which cooperates with the internal spline in the output shaft 303 of the motor unit 300.
  • the coupling can be integrally rotated with the output shaft 303.
  • the busbar 307 of the motor unit 300 projects into the dry cavity of the transmission unit 200, and is insulated from the insulating window 209 after extending from the opening window above the partition of the inverter side housing 211 of the transmission unit 200.
  • the guide of the grid enters the busbar docking area 214.
  • a flange connection surface of the inverter unit 100 substantially parallel to a plane in which the internal inverter circuit PCB board is located is screwed to the inverter side of the transmission unit 200 in the axial direction of the input shaft 202 of the transmission unit 200.
  • the busbar 105 of the inverter unit 100 extends from the fenestration of the inverter-side housing 211 of the transmission unit 200 into the docking region 214, and is stacked up and down with the busbar 307 of the motor unit 300.
  • the motor unit 300, the transmission unit 200, and the inverter unit 100 are relatively fixed by a detachable mechanical or non-mechanical connection such as a bolt connection, respectively, to constitute an electric drive system.
  • the axial length of the compact electric drive system of the present invention is further compressed, so that it can be disposed not only on the front axle of the vehicle but also on the vehicle.
  • the rear axle acts as the drive system.
  • the actual axial length of the actual product of the compact electric drive system based on Patent Document 1 is about 880 cm or more, which cannot meet the installation space requirement of the rear axle of the vehicle whose installation space is greatly limited, and the compact electric drive of the present invention.
  • the system can at least further compress the axial length of the inverter unit, so that the entire electric drive system can be
  • the axial length is controlled at about 700 cm, so that the same design of the electric drive system can be installed both at the front axle of the vehicle and at the rear axle of the vehicle, and the four-wheel drive demand of the vehicle can be realized with a simple design and structure.
  • the gearbox unit of the present invention is provided with a dry cavity for interposing the electrical connection lines of the motor unit and the inverter unit, the connection line of the electric drive system can be buried in the casing, thereby preventing the electrical connection line from being received.
  • the influence of external muddy water or internal lubricating oil can make the electric drive system as simple as possible, reduce the interference of external wiring, and ensure insulation.
  • the present invention is further provided with an insulating block having an insulating grating in the abutting region of the electrical connection line between the motor unit and the inverter unit, the insulation between the electrical connecting lines can be increased.
  • the electrical connection line does not need to use a thicker busbar for ensuring rigidity as in the technique of Patent Document 1, and a thinner, less rigid busbar or a conductivity can be selected.
  • Better, but less rigid, conductive materials increase the freedom of design and material selection.
  • a conventional flexible wiring harness may be used as the electrical connection line, but the arrangement of the electric drive system of the present invention enables the connection harness to be more conventional than the conventional drive system using a wire harness to connect the inverter and the motor. Short, which significantly simplifies system design, significantly reduces weight, and reduces current losses between the inverter and the motor. Further, in the present embodiment, the inverter provides three-phase alternating current for the motor through the three busbars, but the number of the busbars is not limited thereto, and two or more busbars may be provided depending on the type of the motor or the like.

Abstract

一种汽车电驱动系统及使用该电驱动系统的汽车。汽车电驱动系统包括:逆变器单元(100),用于将外部供给来的直流电能转换成交流电;电动机单元(300),用于将来自逆变器单元(100)的电能转变成机械转动从输出轴(303)输出;变速箱单元(200),使从输入轴(202)传递来的转动减速后输出。电动机单元(300)、变速箱单元(200)和逆变器单元(100)分别具有相对独立的封装壳体,并以电动机单元(300)和逆变器单元(100)沿变速箱单元(200)的输入轴(202)的轴向将变速箱单元(200)夹在中间的方式,可拆卸地相互固定连接在一起。逆变器单元(100)的封装壳体在所述轴向上的厚度最小。

Description

一种汽车用的电驱动系统及使用了该电驱动系统的汽车 技术领域
本发明涉及汽车用的电驱动系统,尤其涉及以电动机为动力输出源的电动汽车或混合动力汽车用的紧凑型电驱动系统。
背景技术
电动汽车或混合动力汽车由于利用了电能作为动力源,相比传统的单纯以汽油或柴油等为动力源的汽车,在减低排放量、节约能源等方面具有显著优势,故在当今推动绿色环保的时代,正逐渐成为汽车产业发展的趁势所向。
在上述以电能为动力源的驱动系统中,基于成本、结构复杂度、维修便利性、以及工作效率等观点,通常采用交流电动机(以下简称作电动机)作为动力输出源。然而,作为电动汽车或混合动力汽车中的储能系统(电池组等),其输出的是直流电,故为驱动交流电动机,需要在储能系统和交流电动机之间配置逆变器,以将直流电转换成交流电供给电动机。电动机以从逆变器供给来的交流电为电源进行工作,其输出轴连接至变速箱,被变速箱减速后提供给车轮,使之转动。
为保证逆变器和电动机的输出功率,不得不加大其外形尺寸,这将导致驱动系统整体占用空间的增大,与尽可能确保汽车的乘用空间形成矛盾。尤其是汽车的后轮位置,由于没有车头发动机舱那样的可供配置尺寸较大的电驱动系统的空间,故无法针对后轮的驱动配置这样的电驱动系统,不得不另行设计驱动系统的原理及布置,导致成本的增加。
在专利文献1中,公开了一种横置式排布的紧凑型电驱动系统,其将逆变器、变速箱、电动机沿变速箱的输入轴方向并排地直线排布,从而减小了电驱动系统的纵向高度,能够节省电驱动系统的纵向占用空间。
[专利文献1]US9030063(B2)
发明内容
然而,在该专利文献1记载的发明中,将逆变器、变速箱、电动机横向排布后,电驱动系统的横向尺寸变得过大,在空间布置上仍然无法满足车轴安装空间的要求,尤其是在安装空间更加受限的后轮车轴,无法采用该电驱动系统进行后轮驱动,故需要另行开发设计一套后轮驱动用的驱动或动力传递系统,导致设计、生产、维护等成本的增加。
另外,在专利文献1记载的发明中,该电驱动系统是被集成为一体,被封装在一个壳体中的,这将导致电驱动系统在生产下线测试或后期维修时,无法针对逆变器、变速箱、电动机按单元分别进行测试或维修、更换,导致测试和维修成本的加大。
本发明是鉴于上述现有技术存在的问题而研发的,其目的之一在于提供一种进一步缩短了横向尺寸的汽车用的电驱动系统。此外,本发明的另一目的在于提供一种既结构紧凑,又便于测试和维修的汽车用的电驱动系统。另外,本发明的再一个目的在于提供一种提高了逆变器单元与电动机单元的电连接的绝缘保护的汽车用的电驱动系统。在此需要说明的是,上述各目的仅为本发明的技术效果的例示,并非要求本发明必须同时实现上述全部目的。
本发明一个方案的汽车用的电驱动系统包括:逆变器单元,用于将外部供给来的直流电能转换成交流电;电动机单元,用于将来自所述逆变器单元的交流电能转变成机械转动,从输出轴输出;变速箱单元,使从输入轴传递来的转动减速后输出。所述电动机单元、所述变速箱单元、所述逆变器单元分别具有相对独立的封装壳体,并以所述电动机单元和所述逆变器单元沿所述变速箱单元的所述输入轴的轴向将所述变速箱单元夹在中间的方式,可拆卸地相互固定连接在一起。所述逆变器单元的所述封装壳体的所述轴向上的厚度最小。
所述逆变器单元内可以包含一块或多块逆变器电路板,所述逆变器电路板被以其电路板面大致垂直于所述轴向的方式配置。
所述逆变器单元的所述封装壳体可以是底面形状与其内部的各电路板的外轮廓的投影形状相匹配的箱体形状。
所述变速箱单元内可以设有隔板,将变速箱单元内划分成齿轮传动腔和用于插通所述电动机单元与所述逆变器单元的电连接线路的干腔,所述干腔可以包括使所述电动机单元与所述逆变器单元的电连接线路相对接的对接区域。
所述电连接线路可以有多组连接线。可以在所述对接区域内设有绝缘块,所述绝缘块可以带有使所述电连接线路的各组连接线间绝缘隔离的绝缘格栅。
所述电连接线路可以是母排。所述电动机单元的母排与所述逆变器单元的母排可以在所述对接区域上下层叠,并以可拆卸的连接方式相互连接。
可以是所述电动机单元的所述输出轴为具有内花键的空心轴,所述变速箱单元的所述输入轴为从所述变速箱单元的封装壳体伸出的、前端具有外花键的轴。所述变速箱单元的所述输入轴插入所述电动机单元的所述输出轴内,其所述外花键与所述电动机单元的所述输出轴的所述内花键配合联接,使得所述变速箱单元的所述输入轴随所述电动机单元的所述输出轴的旋转而旋转。
本发明的另一方案是一种汽车,其采用如上所述的汽车用的电驱动系统作为前轮驱动系统。
所述汽车可以还采用同样的另一套上述汽车用的电驱动系统作为后轮驱动系统。
附图说明
图1是示意性地表示被配置于电动汽车的本发明实施方式的电驱动系统及其相关系统 的图。
图2是表示本发明实施方式的电驱动系统的图,其中图2的(a)是示意性地表示电驱动系统组装后的外观的主视图;图2的(b)是示意性地表示组装后的电驱动系统的纵向剖视图。
图3是示意性地表示本发明实施方式中的绝缘块的构造及其安装位置的图,图3的(a)和(b)分别是用于说明图2的(a)中所示的变速箱单元的逆变器侧壳体及装配在其对接区域的绝缘块的左视图和俯视图。
图4是用于说明作为对比例的专利文献1所公开的逆变器内部电路PCB板的安装方式的图。
图5是示意性地表示本发明实施方式的电动机单元、变速箱单元、逆变器单元的装配关系的爆炸图。
具体实施方式
下面将基于附图具体说明本发明的实施方式,在各附图中,对相同或等同的构成要素标注了相同的标号,并适当省略其说明。
图1是示意性地表示被配置于电动汽车的本发明的电驱动系统及其相关系统的图。在本图1中,以电动汽车为例,表示出本发明的电驱动系统及其相关系统的配置,省略了电动汽车所需的其它系统的表示。如图1所示,本发明实施方式的电动汽车包括电驱动系统10、动力控制系统20、能量储存系统30、前轮半轴40、后轮半轴50。其中,电驱动系统10包括逆变器单元100、变速箱单元200、以及作为交流电动机的电动机单元300,逆变器单元100接受来自能量储存系统30(可以是车载储能式电源或燃料电池电源等电池组)的直流电能,在动力控制系统20的功率控制下将直流电转换成交流电提供给电动机单元300,电动机单元300内的转子在交流电所产生的磁场的作用下旋转,从而将电能转变成机械转动力,通过输出轴将该转动力输出至变速箱单元200,变速箱单元200通过其内部的各齿轮机构的配合使该转动减速,并经过差速齿轮的调整后,输出至车轮的半轴(前轮半轴40、后轮半轴50),驱动车轮转动。
图2是表示本发明实施方式的电驱动系统的图,其中图2的(a)是示意性地表示电驱动系统组装后的外观的主视图;图2的(b)是示意性地表示组装后的电驱动系统的纵向剖视图。下面基于图2具体说明本实施方式的电驱动系统的结构特征。
如图2的(a)和(b)所示,电动机单元300、变速箱单元200、逆变器单元100拥有各自独立的封装壳体,分别构成相对独立的单元。电动机单元300、变速箱单元200、逆变器单元100沿变速箱单元200的输入轴202的方向(同时也是电动机单元300的输出轴303的方向,以下简称作轴向)横向排布在一条直线上。电动机单元300的输出轴侧的法兰连接面309与变速箱单元200的电动机侧壳体210的法兰连接面通过螺栓可拆装地连接,变速箱单元200的逆变器侧壳体211的法兰连接面与逆变器单元100的法兰连接面106 通过螺栓可拆装地连接。
需要说明的是,在本实施方式中,电动机单元300、变速箱单元200、逆变器单元100三者间是通过螺栓连接实现可拆装的机械连接的,但也可以采用卡扣连接、铰链连接等其它可拆装的机械或非机械连接方式,根据需要,连接面也可以不是法兰面。由此,能将电动机单元300、变速箱单元200、逆变器单元100分别作为一个整体地方便拆装,故便于各单元的测试及维护、维修。
图2的(b)中示意性地表示了电动机单元300、变速箱单元200、逆变器单元100各自的主要内部构造。另外,在图2中省略了各单元的冷却系统及具体电子电路的图示。
(电动机单元)
如图2的(b)所示,电动机单元300包括与壳体相对固定的定子301、基于定子301通电后产生的磁场而旋转的转子302、与转子301相对固定并一体地旋转的输出轴303、在输出轴303的两端侧分别可旋转地支承输出轴303的两组轴承304及305、以及与定子301电连接的用于给电动机单元300供电的母排307。其中,输出轴303为空心轴构造,在空心轴的内侧设有用于与变速箱单元200的输入轴的外花键相配合的内花键306。
(变速箱单元)
如图2的(b)所示,变速箱单元200的电动机侧壳体210与逆变器侧壳体211所围成的腔体被内部的隔板212划分成图中上方的干腔201和图中下方的密闭的齿轮传动腔213。干腔201内不充填润滑油,在干腔201的靠电动机单元300侧的端面形成有用于插通电动机单元300的母排307的母排穿孔。另外,在逆变器侧壳体211的隔板212上方,形成为向图中上方开口的凹槽构造,成为电动机单元300的母排307与逆变器单元100的母排105的对接区域214。在变速箱单元200的逆变器侧壳体211的与逆变器单元100连接的法兰连接面上、在与对接区域214对应的区域形成有用于插通逆变器单元100的母排105的母排穿孔。另外,在对接区域214内固定有绝缘块209,介由各母排穿孔插入到对接区域214的母排307和母排105上下交叠在绝缘块209上,通过用螺栓穿过母排307和母排105各自的交叠处所设的用于对接的螺栓孔并进行螺固,使得电动机单元300的母排307与逆变器单元100的母排105电连接,并相对固定于变速箱单元200的逆变器侧壳体211。关于绝缘块209的具体构造,将在后面详细说明。
在变速箱单元200的齿轮传动腔213设有从变速箱单元200的电动机侧壳体210向外部伸出的前端带有与电动机单元300的输出轴的内花键相配合的外花键的输入轴202、可旋转地支承输入轴202的两组轴承215和216、与输入轴202相啮合并随着输入轴202的旋转而旋转的小齿轮203、与小齿轮203相啮合并随着小齿轮203旋转而旋转的大齿轮204、与大齿轮204相配合的差速齿轮组205、作为差速齿轮组205的输出的输出半轴215a和215b、以及分别可旋转地支承输出半轴215a和215b的轴承207a和207b。在齿轮传动腔213内,为润滑各齿轮组的旋转而填充有润滑油,为防止润滑油泄漏而在输入轴202从 变速箱单元200的电动机侧壳体210伸出的部位设有油封构件216。
如上所述变速箱单元200的齿轮传动腔内要填充润滑油,故用于防止润滑油泄漏的油封构件216的作用就较为重要。若采用变速箱单元200的输入轴为内花键的空心轴、使电动机的输出轴插入变速箱单元200并花键联接的构造,则油封构件216可能会在后期的测试或维修过程中因电动机的花键输出轴的多次插入、拔出等而受到损害或缩短寿命。而电动机单元300内并不填充润滑油等,无需油封构件,故通过如本实施方式那样采用使变速箱单元200的输入轴202为伸出变速箱的带外花键的轴、使电动机单元300的输出轴为内花键空心轴的构造,能减少在后期的测试或维修过程中使变速箱单元200的油封构件受到损害或缩短寿命的情况,使油封构件216与输入轴202的配合保持生产下线时的水准。
此外,在本实施方式中,为便于说明,以单速的固定齿比变速箱为例说明了变速箱单元200,但当然也可以采用多速变速箱等。
(绝缘块)
图3是示意性地表示绝缘块209的构造及其安装位置的图。图3的(a)和(b)分别是用于说明图2的(a)中所示的变速箱单元200的逆变器侧壳体211及装配在其对接区域214的绝缘块209的左视图和俯视图。
如图3的(a)所示,在变速箱单元200的逆变器侧壳体211的隔板212上方,形成有供电动机单元300的母排307和逆变器单元100的母排105穿过的开窗217。即,该开窗217沿轴向贯穿变速箱单元200的逆变器侧壳体211。由该开窗217和隔板212围成的凹槽空间构成电动机单元300的母排307与逆变器单元100的母排105的对接区域214。在该对接区域214内设有绝缘块209,绝缘块209通过螺栓连接固定于逆变器侧壳体211。绝缘块209可采用各种无机、有机或混合绝缘材料,只要具有设计所需的绝缘性能即可。
如图3的(a)所示,绝缘块209上设有沿母排走线方向延伸的、向上方突起的绝缘格栅218。在本实施方式中,电动机单元300和逆变器单元100分别设有三条由铜或其它导电材料制成的母排相对接,故绝缘块209共设有四个绝缘格栅218,相邻的绝缘格栅218间形成供母排307和母排105交叠对接的对接空间。
如图3的(b)所示,在每个对接空间处设有用于螺固母排307和母排105的螺栓孔219。在实际进行装配时,使对应的母排307和母排105在绝缘块的对应的对接空间内上下交叠,并使各母排的螺栓孔与该对接空间的螺栓孔在上下方向上同轴地对准,用螺栓穿过已对准的母排307、母排105后螺固于对接空间的螺栓孔,使三者相对固定。或者也可以使绝缘块209的螺栓孔为穿透孔,并在逆变器侧壳体211的相应位置设置螺栓盲孔,使螺栓穿过已对准的母排307、母排105及对接空间的螺栓孔后,螺固于逆变器侧壳体211的相应的螺栓盲孔中,使得母排307、母排105、绝缘块209、逆变器侧壳体211四者相对固定。
在专利文献1所公开的技术中,其逆变器和电动机之间也采用了母排来进行电连接, 每个母排采用12厘米长、2厘米宽、0.5厘米厚量级的导电材料制成,以保证其刚性。与此不同,在本实施方式中,由于在电动机单元300的母排307与逆变器单元100的母排105的对接区域还设置有绝缘块209,绝缘块209的绝缘格栅218能够作为使各三组平行延伸的母排的绝缘构件发挥作用,同时各绝缘格栅218之间所形成的对接空间还作为承载母排的支承构件发挥作用。因此,与专利文献1所公开的技术相比,本发明能够降低母排的刚性要求,节省材料成本,同时还能有效地防止用于对接母排的螺栓在长期使用过程中因颠簸等而造成松动时母排间发生短路、造成电驱动系统重大故障的情况。
另外,在以上的说明中,对于各母排与绝缘块和/或变速箱壳体的固定,以螺栓连接为例进行了说明,该连接方式不限于螺栓连接,还可以是卡扣连接、铰链连接等其它可拆装方式的机械或非机械连接方式。由此,能方便地将各部件拆装,便于各部件的测试、维护、维修。
(逆变器单元)
下面说明本实施方式的逆变器单元及其内部电路板的排布方式。在本发明中,逆变器为直流/交流(DC/AC)电能变换器,用于将能量储存系统30供给的直流电源变换为驱动电动机单元300(交流电动机)所需的交流电源。在本发明中,逆变器单元300可以是有源逆变器、无源逆变器、以及多种不同组合的高性能DC/AC电能变换器。
在说明本实施方式的逆变器单元100的壳体内的逆变器电路PCB板及其相关元器件的排布方式前,先利用图4简要说明作为对比例的专利文献1中的逆变器内部电路PCB板及其相关元器件的排布方式。图4对应于专利文献1的附图8,展示了逆变器内部电路PCB板的安装方式。在图4中,虚线框400示意性地表示其逆变器的外壳,标号401表示逆变器电路PCB板的安装基座,标号402表示逆变器电路PCB板的安装接口,标号403表示逆变器电路PCB板。需要说明的是,在专利文献1所公开的技术中,逆变器电路共有三块PCB板,图4中仅示出其中一块PCB板403。三块PCB板403分别插装在与变速箱集成为一体的安装基座上所设的安装接口402中,三块PCB板呈三角状排布。如图4所示,专利文献1的逆变器中的逆变器电路PCB板403是沿与变速箱输入轴平行的方向(以下称作轴向)装配的,在外部套装逆变器外壳后,逆变器的轴向长度必然要大于PCB板403的轴向长度,造成逆变器的轴向长度过长,进而导致电驱动系统整体的轴向长度过长。此外,其三块PCB板403呈三角状排布,而逆变器外壳400为圆筒形状,PCB板403与外壳400间的无用空间过大,既造成空间的浪费,又不利于PCB板的减震等保护措施的构建。
如图2的(b)所示,本发明实施方式的逆变器单元中主要包含两层逆变器电路PCB板101、102,其上分别安装有各种用于实现逆变器功能的电子元器件。由于逆变器的电路构成及DC/AC变换原理等并非本发明的发明点所在,可采用各种现有的逆变器电路原理及构成,故在此省略其详细的说明。两层PCB板101、102沿与变速箱单元200的输入 轴方向(以下称作轴向)大致垂直的方向排布,靠近逆变器单元100的法兰连接面106的PCB板101与逆变器单元100的壳体之间、以及各PCB板之间通过多根沿轴向延伸的固定柱103相互固定,由此,各PCB板被以层叠的方式固定在逆变器单元100的外壳之内。当然,各PCB板之间也可以不彼此连接固定,而是分别固定于逆变器单元100的壳体。
逆变器单元100的壳体是底面形状与其内部的各PCB板的外轮廓的投影形状相匹配的箱体形状,在本实施方式中,由于各PCB板101、102的形状为四边形,故逆变器单元100的外壳为具有长方体形状的箱体。
以层叠方式装配在一起后的逆变器电路PCB板101、102的轴向厚度小于PCB板本身的长度和宽度,故通过这样排布逆变器单元100内的各PCB板及其相关元器件,能缩短逆变器单元100的轴向长度,进而缩短电驱动系统整体的轴向长度。此外,由于逆变器单元100的外壳是底面形状与其内部的各PCB板的外轮廓的投影形状相匹配的箱体形状,故各PCB板与外壳组装后的内部空间利用率较高,且便于构建有效的电路板保护措施。
另外,在以上的本实施方式的说明中说明了逆变器单元100内装有两块逆变器电路PCB板的例子,但该PCB板的数量显然不限于此,也可以只有一层PCB板,或者是有更多层PCB板的层叠,只要保证逆变器单元100的封装壳体的各方向的厚度中、所述轴向上的厚度最小即可。
图5是示意性地表示本实施方式的电动机单元300、变速箱单元200、逆变器单元100的装配关系的爆炸图。如图5所示,电动机单元300、变速箱单元200、逆变器单元100沿变速箱单元200的输入轴202的轴向(图中单点划线所示)排布,变速箱单元200的输入轴202从电动机侧壳体210的输入轴通孔伸出后伸入电动机单元300的作为空心轴的输出轴303中,其外花键与电动机单元300的输出轴303内的内花键配合联接而能够随输出轴303一体地旋转。同时,电动机单元300的母排307伸入变速箱单元200的干腔中,从变速箱单元200的逆变器侧壳体211的隔板上方的开窗伸出后,在绝缘块209的绝缘格栅的导向作用下进入母排对接区域214。此外,逆变器单元100的与其内部逆变器电路PCB板所在的平面大致平行的法兰连接面沿变速箱单元200的输入轴202的轴向螺固于变速箱单元200的逆变器侧壳体211,同时逆变器单元100的母排105从变速箱单元200的逆变器侧壳体211的开窗伸入到对接区域214,与电动机单元300的母排307上下层叠。最后,电动机单元300、变速箱单元200、逆变器单元100间分别以例如螺栓连接等可拆卸的机械或非机械连接方式相对固定,构成电驱动系统。
与专利文献1等现有技术的横置式紧凑型电驱动系统相比,本发明的紧凑型电驱动系统的轴向长度被进一步压缩,从而不仅能配置于车辆的前轴,还能配置于车辆的后轴作为驱动系统。作为一例,基于专利文献1的紧凑型电驱动系统实际产品的轴向总长度约在880cm以上,无法满足装配空间受到极大限制的车辆后轴的安装空间要求,而本发明的紧凑型电驱动系统由于至少进一步压缩了逆变器单元的轴向长度,故能将电驱动系统整体的 轴向长度控制在700cm左右,从而能将同样设计的电驱动系统既安装在车辆前轴处,又安装在车辆后轴处,以简单的设计和结构实现车辆的四轮驱动需求。
此外,由于本发明的变速箱单元设有用于穿插电动机单元与逆变器单元的电连接线路的干腔,能将电驱动系统的连接线埋入壳体之内,从而能够避免电连接线路受到外部的泥水或内部的润滑油等的影响,同时能使电驱动系统整体更加简洁,减少了外部走线的干扰、确保了绝缘性。
另外,由于本发明在电动机单元与逆变器单元的电连接线路的对接区域还设有带绝缘格栅的绝缘块,故能增加各电连接线路间的绝缘性。同时,由于绝缘格栅的隔离作用,电连接线路无需如专利文献1的技术那样为确保刚性而采用厚度较厚的母排,可以选用厚度较薄、刚性较低的母排,或者选用导电性更好但自身刚性较低的导电材料,增加了设计和材料选用的自由度。或者,也可以采用传统的具有柔性的线束来作为电连接线路,但相比于传统的采用线束连接逆变器和电动机的驱动系统,本发明的电驱动系统的排布方式能使连接线束更短,从而显著简化系统设计、大幅减轻重量、降低逆变器与电动机之间的电流损耗。另外,本实施方式中例示了逆变器通过三条母排为电机提供三相交流电的方式,但母排数量不限于此,也可以根据电机的类型等设置两条或多于三条的母排。
另外,本发明并非限定于上述实施方式和变形例,可在不脱离技术思想的范围内使构成要素变形并具体化。可以通过将上述实施方式和变形例所公开的多个构成要素适当组合而形成各种各样的发明。此外,也可以从上述实施方式和变形例所示的所有构成要素中删除几个构成要素。

Claims (9)

  1. 一种汽车用的电驱动系统,其特征在于,包括:
    逆变器单元,用于将外部供给来的直流电能转换成交流电,
    电动机单元,用于将来自所述逆变器单元的交流电能转变成机械转动,从输出轴输出,以及
    变速箱单元,使从输入轴传递来的转动减速后输出;
    其中,所述电动机单元、所述变速箱单元、所述逆变器单元分别具有相对独立的封装壳体,并以所述电动机单元和所述逆变器单元沿所述变速箱单元的所述输入轴的轴向将所述变速箱单元夹在中间的方式,可拆卸地相互固定连接在一起;
    所述逆变器单元的所述封装壳体的所述轴向上的厚度最小。
  2. 如权利要求1所述的汽车用的电驱动系统,其特征在于,
    所述逆变器单元内包含一层或多层逆变器电路板,所述逆变器电路板被以其电路板面大致垂直于所述轴向的方式配置。
  3. 如权利要求2所述的汽车用的电驱动系统,其特征在于,
    所述逆变器单元的所述封装壳体是外形与其内部的各电路板的外轮廓的投影形状相匹配的箱体形状。
  4. 如权利要求1至3的任一项所述的汽车用的电驱动系统,其特征在于,
    所述变速箱单元内设有隔板,将变速箱单元内划分成齿轮传动腔和用于插通所述电动机单元与所述逆变器单元的电连接线路的干腔;
    所述干腔包括使所述电动机单元与所述逆变器单元的电连接线路相对接的对接区域。
  5. 如权利要求4所述的汽车用的电驱动系统,其特征在于,
    所述电连接线路有多组连接线;
    在所述对接区域内设有绝缘块,所述绝缘块带有使所述电连接线路的各组连接线间绝缘隔离的绝缘格栅。
  6. 如权利要求5所述的汽车用的电驱动系统,其特征在于,
    所述电连接线路是母排;
    所述电动机单元的母排与所述逆变器单元的母排在所述对接区域上下层叠,并以可拆卸的连接方式相互连接。
  7. 如权利要求1所述的汽车用的电驱动系统,其特征在于,
    所述电动机单元的所述输出轴为具有内花键的空心轴;
    所述变速箱单元的所述输入轴为从所述变速箱单元的封装壳体伸出的、前端具有外花键的轴;
    所述变速箱单元的所述输入轴插入所述电动机单元的所述输出轴内,其所述外花键与所述电动机单元的所述输出轴的所述内花键配合联接,使得所述变速箱单元的所述输入轴随所述电动机单元的所述输出轴的旋转而旋转。
  8. 一种汽车,采用如权利要求1至7的任一项所述的汽车用的电驱动系统作为前轮驱动系统。
  9. 如权利要求8所述的汽车,其特征在于,
    还采用如权利要求1至7的任一项所述的汽车用的电驱动系统作为后轮驱动系统。
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US20180290530A1 (en) 2018-10-11
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