81results about How to "Improve NVH performance" patented technology

The invention relates to the technical field of vehicle range extending control, and discloses a control method and device for a vehicle range extender, electronic equipment and a storage medium, and the method comprises the steps: obtaining power generation working points corresponding to the range extender in different preset environment temperature ranges when a vehicle meets different preset NVH standards, and building a corresponding relation; when it is detected that the vehicle needs to work to generate power through a range extender in the remaining mileage and the remaining electric quantity of a battery pack of the vehicle is smaller than the preset starting electric quantity, the current preset NVH standard and the current environment temperature of the vehicle are determined; and determining a corresponding target power generation working point according to the current preset NVH standard, the current environment temperature and the corresponding relation, and controlling the range extender to work for power generation based on the power generation power corresponding to the target power generation working point and the rotating speed. Therefore, when the electric quantity of the vehicle is lower than a higher preset starting electric quantity, the range extender works at the target power generation point corresponding to the current NVH standard, so that the NVH performance of the vehicle is better, and the power generation amount required by the vehicle in the remaining mileage can be basically met.

The invention discloses a machining method for an input shaft of an electric drive assembly generator. The machining method comprises the following steps of first finish turning, second finish turning, gear hobbing, spline broaching, heat treatment, spline hard broaching, outer circle and end face grinding and gear grinding. In the step of hard pulling of the spline, the internal spline is subjected to hard pulling after being heated, the large diameter, the small diameter and the tooth side of the internal spline are subjected to hard pulling, and the precision of the internal spline subjected to heat treatment is corrected. In the step of grinding the outer circle and the end face, an internal spline of the input shaft of the generator is expanded, the end face and a center hole are positioned, and the outer circle and the end face of the input shaft of the generator are ground. In the gear grinding step, the internal spline of the input shaft of the generator is expanded, the end face is positioned, and gear grinding is conducted on the gear. Thermal deformation of the internal spline is corrected after heat treatment, then the internal spline is adopted as a standard for machining of subsequent procedures, the standard is unified, and it is guaranteed that the internal spline of the generator input shaft and the external spline of the generator rotor are well matched, torque is transmitted, a bearing operates stably, and operation stability of an electric drive assembly is guaranteed.

The application provides an automobile engine compartment drainage air intake system and a vehicle, and belongs to the technical field of automobile parts, wherein the automobile engine compartment drainage air intake system comprises a ventilation cover plate, an air chamber, a left drainage groove structure and a right drainage groove structure; the middle part of the top plate of the air chamber is concave downward, and an accommodation space extending along the length direction of the air chamber is formed between the top plate and the ventilation cover plate; the left drainage groove structure is arranged below the ventilation cover plate; the right drainage groove structure comprises a drainage groove body, the drainage groove body is arranged in the accommodation space, and the opening of the drainage groove body is communicated with the water inlet. The automobile engine compartment drainage air intake system provided by the application correspondingly sets the drainage groove structure as the left drainage groove structure and the right drainage groove structure; two drainage groove structures are used for drainage respectively, so that the drainage groove structure does not span the width direction of the vehicle body, the space occupation area of the drainage groove is smaller, the size of the engine compartment is reduced, the layout in the engine compartment is optimized, and the engine compartment maintenance is facilitated.

The radial flexible mechanism of the scroll compressor comprises a main shaft, a crankshaft seat is arranged at the output end of the main shaft, an eccentric hole is axially formed in the end portion of the end, away from the main shaft, of the crankshaft seat, and a crank pin is fixedly connected into the eccentric hole. The outer side of the end, away from the crankshaft seat, of the crank pin is fixedly sleeved with an eccentric shaft sleeve, one side of the eccentric shaft sleeve is fixedly connected with an eccentric block, a limiting groove is formed in the outer side of the end, close to the eccentric block, of the crankshaft seat, and an elastic washer is arranged on the inner side of the limiting groove. The groove is formed in the outer side of the crankshaft seat on the main shaft, and the rubber ring is fixed on the crankshaft, so that the collision between the eccentric block and the crankshaft is avoided, and the NVH (Noise Vibration and Harshness) performance is favorably improved; due to the fact that the rubber ring is additionally arranged, the self-aligning function has a buffering function, too intense self-aligning and rollback are avoided, and the movable disc of the compressor is more stable in operation, low in noise and good in NVH expression homogeneity.

According to the A-column structure and the vehicle, the A-column structure comprises an A-column framework and a peripheral plate, the A-column framework comprises an A-column inner plate and an A-column outer plate, the peripheral plate comprises a connecting rib plate and an outer decorative plate, and the portion, close to a front windshield, of the outer decorative plate is arranged to be a straight portion parallel to front windshield glass; the outer decoration plate is connected to the A-column outer plate through the connecting rib plate so as to cover the middle of the A-column outer plate and the portion, close to the front baffle, of the A-column outer plate, the side, away from the straight portion, of the outer decoration plate extends to the side window glass, and the side window glass covers the portion, close to the side window, of the A-column outer plate. The arrangement of the straight part of the outer decorative plate can shield the mounting parts of the front windshield glass and the A-column framework, and has the same decoration effect as the black area of the original front windshield glass, so that the arrangement of the black area of the front windshield glass can be cancelled, and the A-column barrier angle is reduced; the straight part is directly overlapped with the front windshield while reducing wind resistance, the size chain is short, matching is easy, and the NVH performance of the passenger car cannot be affected.

The invention belongs to the technical field of automobile active suspension damping systems, and particularly relates to a mute stiffness valve and a control method thereof. The stiffness valve is switched from an open state to a closed state, and the plunger at least comprises a first stroke section, a second stroke section and a third stroke section; in the first stroke section, first direction current is input into the voice coil motor structure, so that the plunger is in an acceleration state; in the second stroke section, current input to the voice coil motor structure is stopped and / or second-direction current opposite to the first-direction current is input, so that the plunger is in a deceleration state; and in the third stroke section, the current in the first direction is input into the voice coil motor, so that the sealing element between the plunger and the air vent is compressed and seals the air vent. By controlling the current input into the voice coil motor structure, control over the moving direction and speed of the plunger is achieved, on the premise of quick response, the impact force generated when the plunger makes contact with the sealing support is remarkably reduced, and noise generated by impact is restrained.

An automobile wire harness installation structure comprises a main body, the main body is installed on an automobile body metal plate, a via hole used for installing the main body is formed in the automobile body metal plate, the main body comprises a wire harness hole, a wire harness penetrates through the wire harness hole, a sealing part and a guiding part are arranged on the main body, the sealing part is used for being connected with the via hole in a sealed mode, and the guiding part is used for being connected with the guiding part. The guide part is located on at least one of the first side and the second side of the main body, and the guide part is configured to enable the guide part to be in contact with the wire harness when the wire harness is arranged in the wire harness hole in a penetrating mode, so that the stability and the sealing performance of wire harness installation can be improved, good dustproof and waterproof effects are achieved, and the NVH performance of a vehicle is improved.

The utility model relates to a split type motor stator. The split type motor stator has a coil assembly including a plurality of coil strands disposed in the split type motor stator, the split type motor stator including: a first core located on a first side of the coil assembly in a direction of a rotation axis of the coil assembly, and including a receiving groove in which the coil strands are received; the coil stranded wire is inserted into the accommodating groove; and a second core portion located on a second side of the coil assembly and coupled to the first core portion to fix a position of the coil assembly.

This invention provides a method, apparatus, device, and storage medium for optimizing gear parameters in a speed reducer. The method includes: acquiring a sample set of gear pairs in the speed reducer, as well as the gear parameters and modification ranges of the gear parameters; inputting a portion of the sample set as training samples into a preset speed reducer simulation model to obtain first simulation values ​​for each training sample under various operating conditions, the first simulation values ​​including transmission error and peak-to-peak value of transmission error; calculating the mean and variance of the transmission error and peak-to-peak value of the training sample under different operating conditions based on the first simulation values ​​of the same training sample, and determining them as second simulation values; performing fitting calculations based on the training samples and the second simulation values ​​to determine a surrogate model; and constructing a gear parameter optimization model based on the surrogate model and the modification range, so that the gear parameter optimization model outputs optimized values ​​for each gear parameter based on the second simulation values. This invention not only improves the NVH performance of the speed reducer but also enhances the versatility of gear parameters.

The utility model discloses a door slot sealing strip and a vehicle, the door slot sealing strip comprises a support main body, one end of the support main body is installed in a first gap between front windshield glass and a vehicle body A column, the other end of the support main body is provided with a first support part and a second support part which are forked, the first support part is connected with the front windshield glass, and the second support part is connected with the vehicle body A column; the sealing body comprises a first sealing section and a second sealing section, one end of the first sealing section is connected with the first supporting part, the other end of the first sealing section is connected with the automobile door to seal a second gap between the automobile door and the front windshield, one end of the second sealing section is connected with the second supporting part, and the other end of the second sealing section is connected with the automobile door. And a third gap between the vehicle door and the vehicle body A column is sealed. The three sealing structures are arranged to seal the front windshield and the vehicle body A column, seal the vehicle door and the front windshield and seal the vehicle door and the vehicle body A column respectively, so that the vehicle sealing waterproof performance and the vehicle NVH performance are improved.

This invention belongs to the field of vibration and noise reduction technology for new energy vehicles, specifically involving a low-noise design and evaluation method for electric drive systems based on acoustic metamaterials. The method involves determining the peak intensity and frequency of the vibration and noise response of the electric drive system, identifying the significant area of ​​working deformation of thin-walled components in the electric drive system, and determining the installation position of the acoustic metamaterial based on this area. It also involves determining the design boundary parameters of the acoustic metamaterial, designing a local resonant element, artificially constructing the local resonant element, prototyping the acoustic metamaterial based on the artificial construction scheme of the local resonant element in step five, installing the acoustic metamaterial in the determined installation area, and verifying its noise reduction performance. Finally, it determines whether the artificial construction scheme parameters are optimal; if optimal, the acoustic metamaterial scheme is determined. This invention systematically proposes a method for using acoustic metamaterials to mitigate single-frequency noise radiated by the thin-walled structure of the electric drive system, and clarifies the precise selection method for the installation position of the acoustic metamaterial on the thin-walled structure of the electric drive system.

The application relates to a double-motor automatic variable-speed electric driving system and a variable-speed transmission, belonging to the technical field of electric driving systems, which comprises a first motor, a second motor and a system output shaft for driving connection with a downstream system, the two rotor shafts of the first motor and the second motor are coaxially arranged, the rotor shaft of the first motor is arranged through the rotor of the second motor and the rotor shaft of the second motor in a relatively freely rotatable mode, and the two rotor shafts and the system output shaft are arranged in parallel; the two rotor shafts are connected with the system output shaft through a two-gear variable-speed structure. The coaxial arrangement of the rotor shafts of the two motors and the parallel arrangement of the two rotor shafts and the system output shaft reduce the volume, so that the electric driving system is compact in structure; the two-gear variable-speed structure is used for realizing two-gear variable-speed control of the downstream system, so that the transmission structure of the electric driving system is simplified.

The utility model provides a transmission system and a vehicle. The transmission system comprises an engine which comprises an oil pan, and an oil storage cavity is formed in the oil pan; the speed reducer comprises a speed reducer shell and a first half shaft, the speed reducer shell is arranged on one side, in the first direction, of the oil pan and connected with the oil pan, the first half shaft extends in the first direction, one end of the first half shaft is located in the speed reducer shell, and the other end of the first half shaft is located in the oil pan. The first half shaft is arranged on the two opposite side walls of the oil pan in the first direction in a penetrating mode. The support assembly is arranged on the side, away from the speed reducer shell in the first direction, of the oil pan and connected with the oil pan, the support assembly is provided with a supporting hole, and the first half shaft further penetrates through the supporting hole. The integrated design of the speed reducer and the engine can be achieved, so that the installation convenience of the speed reducer is improved, and then the arrangement convenience of the transmission system on the vehicle is improved.

This invention discloses a frame-based screw-connected powertrain suspension bracket structure, including a frame crossbeam. A left end plate, a right end plate, and a lower end plate are connected to the frame crossbeam. Both the left and right end plates have mounting bolt connection holes. The left and right end plates each have connecting flanges on their sides. The lower end plate has a connecting portion. One end of the connecting flange and one end of the connecting portion are respectively connected to the top and bottom of the frame, and the other end of the connecting flange is connected to the other end of the connecting portion. Using this frame-based screw-connected powertrain suspension bracket structure improves layout flexibility, optimizes the dynamic stiffness and vibration isolation performance of the mounting point, and enhances connection reliability.

This disclosure relates to a motor controller and its housing, and a vehicle. The housing of the motor controller has an opening (10) for mounting a connector (2), wherein a retaining wall (11) for protecting the connector (2) is provided on the outer periphery of the opening (10) on the housing (1). In the housing of the motor controller provided in this disclosure, a retaining wall is added to the outer periphery of the connector, and the connector is located in the internal space enclosed by the retaining wall, which can seal and protect the connector, thereby improving its salt spray resistance. Furthermore, the retaining wall and the housing can be an integral structure, which can improve the overall rigidity of the motor controller housing, thereby improving NVH performance.

The exhaust sound insulation cover comprises a cover body used for covering an exhaust hole, the cover body is provided with a first opening, the first opening is opened towards the bottom of a vehicle, and a sound absorption layer is arranged on the inner wall of the cover body. The invention further discloses a vehicle body and a vehicle. The exhaust function can be achieved, noise transmitted into a vehicle from the outside of the vehicle can be reduced, and the NVH performance of the vehicle is improved.

This utility model proposes a battery pack cover and a battery pack. The battery pack cover includes a cover body, which comprises an upper plate profile and a lower plate profile. The upper and lower plate profiles are arranged parallel to each other and are fixedly connected by multiple connecting structures. This utility model adopts a double-layer plate profile and multi-point connection structure design, which significantly improves the overall rigidity and impact resistance of the battery pack cover. The upper and lower plate profiles form a stable grid-like support frame through horizontally, vertically, and obliquely arranged reinforcing ribs, and can be optionally equipped with intermediate support structures such as honeycomb core material or foam filling, which effectively improves bending and torsional resistance, suppresses large-span deformation, and enhances top protection through structural energy absorption mechanism, solving the technical problems of insufficient rigidity, easy deformation, and poor impact resistance of traditional single-layer plate structures.

The lower vehicle body floor structure comprises a front wall plate, a front floor, a middle floor, a rear floor and a rear wall plate which are integrally formed, a front wall cross beam is integrally formed on the front side of the front wall plate, a seat cross beam is integrally formed above the front floor, and a rear floor cross beam is integrally formed below the rear floor. The front wall cross beam, the seat cross beam and the rear floor cross beam extend in the left-right direction of the vehicle body and are each provided with a left-right through cavity. According to the lower vehicle body floor structure, the dash panel, the front floor, the middle floor, the rear floor and the rear panel are integrally formed, the integration degree is high, the manufacturing precision of products can be guaranteed conveniently, the manufacturing efficiency of the products is improved, the structural strength of corresponding parts is enhanced through the arrangement of the front wall cross beam, the seat cross beam and the rear floor cross beam, and the service life of the lower vehicle body floor structure is prolonged. According to the structure, the overall strength, rigidity and durability of the floor structure are guaranteed, and the overall NVH performance of a vehicle is improved.

The application discloses a hinge assembly and a vehicle, and belongs to the technical field of vehicle accessories. The hinge assembly is applied to a vehicle, and comprises a hinge and a first connecting piece. The hinge is provided with a first connecting part used for being connected with a vehicle body of the vehicle. The first connecting piece is used for connecting the first connecting part and the vehicle body. The first connecting part is used for being sealingly matched with an outer surface of the vehicle body, and the first connecting part is sealingly matched with the first connecting piece. The hinge assembly can solve the problem of poor sealing performance of the hinge in the prior art.

The embodiment of the present application provides an engine multi-connecting rod mechanism, an engine and a vehicle, relates to the technical field of engines, and aims at improving the technical problem that the piston impacts the cylinder wall under the action of the connecting rod in the prior art, thereby causing poor NVH performance.The engine multi-connecting rod mechanism comprises a crankshaft, a piston and an intermediate connecting rod; the intermediate connecting rod comprises a first arm rod and a second arm rod; one end of the first connecting rod, which is away from the crankshaft, is movably connected with the first arm rod; one end of the second connecting rod, which is away from the piston, is movably connected with the connecting part; and one end of the second arm rod, which is away from the first arm rod, is movably connected with the cylinder wall.The intermediate connecting rod is arranged, and the first arm rod and the second arm rod are arranged at an included angle, so that the swing range of the second connecting rod is reduced, the piston is prevented from impacting the cylinder wall during movement in the cylinder wall, vibration and noise caused by the piston impacting the cylinder wall are weakened, and the NVH performance of the engine is improved.

The invention relates to the technical field of electric driving systems, and discloses an electric driving system with a hydraulic torque converter and a forklift. The system comprises a driving motor, a hydraulic torque converter, a speed reducer and a vehicle control unit, wherein a lock-up clutch is integrated in the hydraulic torque converter; an output shaft of the driving motor is connected with a pump wheel input side of the hydraulic torque converter; a turbine output side of the hydraulic torque converter is connected with an input shaft of the speed reducer; the output end of the reducer is connected with a vehicle drive axle; when the vehicle is in the low-speed large-torque demand working condition, the lock-up clutch is controlled to be separated, so that the hydraulic torque converter works in the torque conversion working condition, and when the vehicle is in the low-speed large-torque demand working condition, the lock-up clutch is controlled to be separated; and when the vehicle is in a high-speed small-torque demand working condition, the lock-up clutch is controlled to be engaged, so that the pump wheel of the hydraulic torque converter is mechanically locked with the turbine, and the vehicle is in a coupler working condition. The power performance and the energy efficiency of the vehicle are improved, the cost of the electric drive system is reduced, and the economical efficiency and the NVH performance are improved.

This invention provides a window sealing structure assembly and a vehicle, belonging to the technical field of vehicle components. It includes a window frame, and sequentially integrated components forming a ring: a welt groove, a rear lower joint, a water-cutter, and a front lower joint. The water-cutter is located below the welt groove. A mounting groove is formed on the window frame at the open edge of the window frame, corresponding to and engaging with the welt groove. The opening of the mounting groove faces the open window frame and is located inside the outer panel of the window frame. The welt groove fits tightly against the outer surface of the window frame. The water-cutter connects to the lower edge of the open window frame. This invention reduces the channels for internal and external airflow at the sealing structure around the open area of ​​the window frame, which is beneficial for improving the vehicle's NVH performance; it reduces the number of parts during assembly, effectively reducing assembly steps and lowering assembly difficulty; and it ensures a smooth and aesthetically pleasing appearance.

This invention provides a method, system, and device for optimizing gear profile modification parameters in a transmission, relating to the field of transmission gear profile modification technology. The method includes: constructing a simulation model of the transmission assembly structure; calculating the median point of the modification amount; randomly adding modification amount samples and conducting on-machine NVH tests to obtain measured NVH data; using a modification-vibration generalized extension approximation model, calculating the generalized extension approximation function curves between the tooth profile modification amount and the tooth direction modification amount and the vibration noise value, respectively, to determine the modification amount distribution range; splitting the median point of the modification amount and the modification amount distribution range; reselecting the median point of the modification amount; randomly selecting a preset number of modification amount samples, calculating the set of tooth profile modification amounts, the set of tooth direction modification amounts, and the corresponding transmission error set that satisfy a normal distribution; and statistically analyzing the transmission error set to obtain an NVH distribution pattern diagram. This scheme can effectively design and simulate optimal modification parameters, eliminating subjective factors in the design process.

This invention discloses a cover plate for a drive assembly housing, a drive assembly having the same, and a vehicle. The drive assembly housing includes a lower housing and a cover plate. The lower housing has a mounting opening, and the cover plate closes onto the mounting opening. The cover plate includes a central arched area and a mounting area. The mounting area is an annular structure surrounding the central arched area and is used to contact and connect with the lower housing. The central arched area includes multiple curved panel areas that arch from the periphery towards the center in a direction away from the mounting opening. The electronic control cover plate of this application, by setting the central arched area and the mounting area, can increase the modulus of the electronic control cover plate and increase its natural frequency to a certain extent. This makes the natural frequency of the electronic control cover plate far away from the external excitation vibration frequency caused by the vibration of the drive motor, thereby reducing the resonance between the electronic control cover plate and the drive motor, reducing vibration and noise during drive assembly operation, and reducing resonance fatigue of the drive assembly structure.

The invention relates to a stator winding preparation method, a stator winding, a stator assembly and a permanent magnet motor. The stator winding preparation method comprises the steps that 18 conductors used for winding 9 winding branches of three phases are sequentially laid and wound in a wave winding mode; during tiled winding, the two effective parts of the wave winding pattern of the same-layer overline formed by wave winding of any conductor are arranged on the same layer, and the two effective parts of the wave winding pattern of the two adjacent groove layers are arranged in an up-and-down staggered layer manner; the 18 conductors which are laid and wound are coiled from one ends of the conductors to the other ends of the conductors; during coiling, the coiling direction of the 18 conductors is the direction in which the serial number of the conductor grooves is reduced, and the radial outer sides of the 18 conductors are the sides where the groove layers with the serial number of 1 of the conductor grooves are located. Through the specified coiling process, the problem that the NVH performance of the odd-number-layer stator winding of the continuous wave winding of the permanent magnet motor is poor due to the improper preparation method can be solved.

The invention relates to the field of automatic transmission vehicle control, in particular to a shifting fork gear engaging gear calculation method for a double-clutch automatic gearbox, which comprises the following steps of: according to various preset conditions with different priorities, calculating a shifting fork gear engaging gear position of a TCU (Transmission Control Unit) according to various parameters such as a driving state, a vehicle speed, an accelerator opening degree and an engine rotating speed of a current vehicle; according to the method, the expected gear and the pre-selected gear are obtained according to the factors such as the gear shifting condition, the road condition and the like, re-judgment and calculation are carried out to determine the final shifting fork action target gear most conforming to the current actual condition, and the shifting fork of the double-clutch automatic gearbox is controlled to engage the gear (including the neutral gear) according to the obtained shifting fork gear engaging gear calculation result. The dynamic property and the economical efficiency of the automatic transmission vehicle are guaranteed, the NVH performance of the vehicle is improved, and the comfort and the satisfaction degree of a driver and passengers are improved.

The application discloses a control method and device of a thermal management system, the control method obtains at least operating parameters including cooling liquid inlet stack temperature and cooling liquid outlet stack temperature, obtains fan target rotating speed according to cooling liquid temperature difference and preset temperature difference target value, obtains initial water pump rotating speed according to cooling liquid outlet stack temperature and temperature target value of the cooling liquid outlet stack temperature, and obtains water pump target rotating speed according to the initial water pump rotating speed and preset rotating speed compensation relation. Since the rotating speed compensation relation is a positive proportional change relation between water pump compensation rotating speed and the fan target rotating speed, the rotating speed of the fan and the water pump can be interlocked controlled when the fan of the radiator is controlled to operate at the fan target rotating speed and the water pump is controlled to operate at the water pump target rotating speed, temperature control is guaranteed, the rotating speed of the fan and the water pump can be inhibited mutually, both components are prevented from being at high rotating speed to cause large noise, and the NVH performance of the vehicle-mounted fuel cell stack thermal management system is improved.

The utility model discloses a rear suspension upper swing arm, rear suspension upper swing arm assembly and vehicle, include: swing arm body, by first end to second end along the length direction, swing arm body includes first steel sheet and second steel sheet, first steel sheet and second steel sheet along the length direction of swing arm body extends, and the edge of at least one of first steel sheet and second steel sheet is equipped with the flanging, and the flanging extends along the length direction of swing arm body, and first steel sheet and second steel sheet are welded to form the hollow box -like structure through the flanging, sleeve pipe, including first sleeve pipe and second sleeve pipe, first sleeve pipe is connected in the first end of swing arm body, and forms first mounting point through first sleeve pipe, and second sleeve pipe is connected in the second end of swing arm body, and forms second mounting point through second sleeve pipe. Compared with casting or straight steel pole, the strength is better, the performance is better, the maximum promotion strength, rigidity and buckling performance, effectively promote the whole car handling stability performance, NVH performance and endurance performance, and reach the cost optimum simultaneously.

This utility model discloses a coolant reservoir assembly, a cooling system thereon, and a vehicle, belonging to the field of vehicle cooling systems. The coolant reservoir assembly includes a coolant reservoir, a vibration isolator, and a limiting bracket. The coolant reservoir is mounted on the vehicle's base component and includes a vibration isolator mounting portion. The vibration isolator is fitted onto the mounting portion and is used to reduce and suppress vibration loads transmitted from the vehicle body to the coolant reservoir. The limiting bracket is mounted on the base component and is positioned circumferentially with the base component, preventing the vibration isolator from shifting and thus limiting the vibration amplitude of the coolant reservoir. This not only solves the problem of coolant reservoir shaking during vehicle operation but also improves the vehicle's NVH performance and the passenger's riding experience.

The stator assembly comprises a stator core and an M-phase stator winding, the stator core is provided with N slots, the stator winding is formed by winding a plurality of hairpin coils into L layers in the slots, each phase of stator winding comprises two sub-windings, each sub-winding is provided with a plurality of hairpin coils, the plurality of hairpin coils are distributed in L different layers of the N slots, the plurality of hairpin coils of each sub-winding comprise a first hairpin coil positioned on the first layer, a second hairpin coil positioned on the Lth layer and a middle hairpin coil positioned between the first layer and the Lth layer; the first hairpin coils of the two sub-windings are short-distance hairpin coils, and the second hairpin coils of the two sub-windings are long-distance hairpin coils; the total number of the middle hairpin coils of the two sub-windings is the same, the pitch types of the middle hairpin coils are the same, and the distribution of the pitch types is the same. The counter electromotive force, the resistance and the inductance of each sub-winding are the same, and the assembly efficiency of the winding is improved.