Motor peak performance test method and device

Abstract

The application provides a motor peak performance testing method and device, which comprises: a setting step for setting the maximum allowable power supply current of the motor and testing the peak performance of the motor by using the set maximum allowable power supply current; an adjusting step for adjusting the set maximum allowable power supply current to decrease with the increase of the rotation speed of the motor when the rotation speed of the motor reaches a predetermined rotation speed during the testing of the performance of the motor according to the set maximum allowable power supply current; and a continuous testing step for continuously testing the peak performance of the motor by using the adjusted maximum allowable power supply current. Thus, the highest copper loss density can be kept basically constant with the increase of the rotation speed of the motor.

Description

Technical Field

[0001] This invention relates to the field of motor technology, and in particular to a method and apparatus for testing the peak performance of motors. Background Technology

[0002] In certain scenarios, such as when users need to understand the performance of a motor in order to select a suitable motor that meets their needs, it is necessary to test the performance of the motor before it leaves the factory.

[0003] Existing motor performance testing methods may only consider voltage and current limitations. However, the peak performance requirements of new energy electric vehicles typically include sufficient duration (10–30 seconds) at each speed within the allowable temperature rise range (depending on the winding insulation level). Currently, most such motors use rectangular flat wires due to high slot fill ratios and good quality control. However, because rectangular flat wires have a strong skin effect at high speeds, the current density of the conductors in the stator slots is severely uneven, leading to a higher temperature rise at high speeds. Traditional peak performance estimation methods may not be able to account for this higher temperature rise at high speeds. Summary of the Invention

[0004] In view of this, the present invention provides a method and apparatus for testing the peak performance of a motor.

[0005] To address the aforementioned technical problems, according to an embodiment of the present invention, a method for testing the peak performance of a motor is provided, applicable to a flat-wire motor in a new energy vehicle. The method includes: a setting test step, used to set a maximum allowable supply current for the motor and test the peak performance of the motor using the set maximum allowable supply current; an adjustment step, used to adjust the set maximum allowable supply current so that it decreases as the motor speed increases when the motor speed reaches a predetermined speed during the performance test according to the set maximum allowable supply current; and a continuing test step, used to continue testing the peak performance of the motor using the adjusted maximum allowable supply current.

[0006] To address the aforementioned technical problems, according to another embodiment of the present invention, a motor peak performance testing device is provided, applied to a flat-wire motor for new energy vehicles, comprising: a setting test module for setting the maximum allowable supply current of the motor and testing the peak performance of the motor using the set maximum allowable supply current; an adjustment module connected to the setting test module for adjusting the set maximum allowable supply current to decrease as the motor speed increases when the motor speed reaches a predetermined speed during the performance test according to the set maximum allowable supply current; and a continuing test module connected to the adjustment module for continuing to test the peak performance of the motor using the adjusted maximum allowable supply current.

[0007] According to the method and apparatus for testing the peak performance of a motor of the present invention, the peak performance of the motor is tested using a set maximum allowable supply current. During this period, if the speed of the motor reaches a predetermined speed, the set maximum allowable supply current is reduced as the speed of the motor increases, and the peak performance of the motor is tested again using the adjusted maximum allowable supply current.

[0008] Therefore, compared with existing technologies that only consider current and / or voltage limits without considering the skin effect when testing the peak performance of motors, the present invention considers both current limits and the skin effect when testing the peak performance of motors. Thus, by reducing the maximum allowable supply current applied to the motor when the motor speed reaches a predetermined speed, the maximum copper loss density can be kept essentially constant as the motor speed increases.

[0009] Other features and aspects of the invention will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0010] The accompanying drawings, which are included in and form part of this specification, illustrate exemplary embodiments, features, and aspects of the invention together with the specification and serve to explain the principles of the invention.

[0011] Figure 1 This is a flowchart of a method for testing the peak performance of motors in related technologies.

[0012] Figure 2 This is a flowchart illustrating a method for testing the peak performance of a motor according to an exemplary embodiment.

[0013] Figure 3 This is a flowchart illustrating an example of a method for testing the peak performance of a motor according to an exemplary embodiment.

[0014] Figure 4This is a schematic diagram comparing the peak performance of a motor after applying the peak performance testing method of this embodiment and related technologies.

[0015] Figure 5 This is a schematic diagram comparing the copper loss density in the last conductor of the stator slot after applying the motor peak performance testing method of this embodiment and related technologies.

[0016] Figure 6 This is a block diagram illustrating an engine start control device for a hybrid electric vehicle according to an exemplary embodiment. Detailed Implementation

[0017] Various exemplary embodiments, features, and aspects of the present invention will now be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings denote elements that have the same or similar functions. Although various aspects of the embodiments are shown in the drawings, they are not necessarily drawn to scale unless specifically indicated otherwise.

[0018] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments.

[0019] Furthermore, to better illustrate the present invention, numerous specific details are provided in the following detailed embodiments. Those skilled in the art should understand that the present invention can be practiced without certain specific details. In other instances, methods, means, elements, and circuits well known to those skilled in the art have not been described in detail in order to highlight the spirit of the invention.

[0020] It should be understood that conductors are affected by the skin effect. When a conductor carries alternating current or an alternating electromagnetic field, the current distribution inside the conductor is uneven; the current concentrates in the conductor's "skin," meaning it's concentrated in a thin outer layer. The closer to the surface, the greater the current density, while the actual current inside the conductor is relatively small. This results in increased resistance and power loss, a phenomenon known as the skin effect. Clearly, the skin effect causes significant waste of current and energy, hindering efficient energy utilization.

[0021] Figure 1 This is a flowchart of a method for testing the peak performance of a motor in related technologies. In related technologies, the following methods can be used... Figure 1 The peak performance test method shown is used to test the peak performance of the motor. This peak performance test method includes:

[0022] In step S110, the maximum allowable supply voltage (U) applied to the motor is defined based on the battery capacity and the power electronic unit (PEU) capacity.m ) and maximum allowable supply current (I m ).

[0023] In step S120, the lead angle and current interval are set, that is, the lead angle θ and the current step size are set, where tan(θ) = i d / i q I s ≤I m , i d i represents the D-axis output current (i.e., the D-axis component of the stator current). q This is the output current on the Q-axis (that is, the Q-axis component of the stator current).

[0024] In step S130, the electromagnetic torque (T) of the motor is calculated using the lead angle and current interval set in step S120. e ), motor D-axis voltage (U d ), Q-axis voltage of the motor (U) q ) and the terminal voltage of the motor (U) s That is, the D-axis component U of the stator voltage corresponding to each current is calculated according to the set step size. d Q-axis component U of stator voltage q U s And T e In one possible implementation, U can be calculated using the following formulas 1, 2, 3, and 4. d U q U s And T e :

[0025]

[0026] U d =-w e L q i q Formula 2

[0027]

[0028]

[0029] Among them, P n L represents the number of pole pairs of the motor. d L is the motor inductance for the D-axis. q The motor inductance for the Q-axis. For the permanent magnet flux linkage of the motor, w e The electrical angle is the first intersection point B of the maximum torque-voltage ratio control curve of the motor and the current limit circle.

[0030] In step S140, all rotational speed points are scanned to filter out voltages exceeding the maximum allowable supply voltage U. m The point that satisfies U. That is, delete the point that satisfies U. s >U m All rotational speeds.

[0031] In step S150, the maximum torque value and maximum power value corresponding to each motor speed are found.

[0032] In step S160, the peak torque curve and the peak power curve are output. The peak torque curve can be obtained by connecting the maximum torque values ​​at all speed points, and the peak power curve can be obtained by connecting the maximum power values ​​at all speed points.

[0033] However, the above-mentioned motor performance testing methods may only consider voltage and current limitations, such as only considering the maximum permissible supply voltage U applied to the motor. m and maximum allowable supply current I m However, the skin effect was not considered, which may lead to uneven current density in the conductors of the stator slots.

[0034] Specifically, the peak performance requirements for new energy electric vehicles typically also include sufficient duration at various motor speeds within the allowable temperature rise range (depending on the insulation level of the windings). (seconds). Currently, due to high slot fill ratios and good quality control, most such motors use rectangular flat wires. However, because rectangular flat wires have a strong skin effect at high speeds, the current density of the conductors in the stator slots is severely uneven. This leads to a higher temperature rise in the motor at high speeds, which in turn causes the maximum copper loss density to become inconsistent as the motor speed increases.

[0035] Therefore, the present invention realizes that during the testing of motor performance, when the motor speed reaches a certain value, the maximum allowable supply current used during the testing of motor performance can be reduced, so that the maximum copper loss density remains basically constant as the motor speed increases.

[0036] Specifically, the present invention proposes a method and apparatus for testing motor performance. The method uses a set maximum allowable supply current to test the peak performance (e.g., peak torque and peak power) of the motor. During this process, if the motor speed reaches a predetermined speed, the set maximum allowable supply current is adjusted so that the maximum allowable supply current decreases as the motor speed increases. Then, the adjusted maximum allowable supply current is used to continue testing the peak performance of the motor.

[0037] Therefore, when testing the peak performance of the motor, not only current limitation but also skin effect are taken into account. By reducing the maximum allowable supply current applied to the motor as the motor speed increases, the highest copper loss density can be kept basically constant as the motor speed increases.

[0038] To better understand this invention, the following is combined with Figure 2 The flowchart shown illustrates the motor performance testing method of the present invention in detail.

[0039] Figure 2 This is a flowchart illustrating a motor performance testing method according to an exemplary embodiment. This method can be applied to flat-wire motors in new energy vehicles, where a flat-wire motor refers to a motor using flat wires, such as rectangular flat wires. In one implementation, the new energy vehicle may include a motor and its controller (i.e., a motor controller), which can employ the motor performance testing method of this invention to perform performance testing on the flat-wire motor of the new energy vehicle. Figure 2 As shown, the motor performance testing method may include the following steps.

[0040] In step S220, the maximum allowable power supply current I of the motor is set. m and use the set maximum allowable supply current I m The peak performance of the motor is tested. Step S220 corresponds to setting the test steps.

[0041] In this embodiment, the maximum allowable power supply current I of the motor m This refers to the maximum permissible supply current that the motor controller can apply to the motor. It should be understood that the larger the current applied by the motor controller, the shorter the duration it can be maintained. Therefore, it is necessary to set the maximum permissible supply current I within a specified time. m This limits the current output by the motor controller, thereby preventing the duration of operation from being too short due to excessive current.

[0042] In one possible implementation, the motor controller can set the maximum allowable supply current of the motor based on parameters related to the motor's current limit.

[0043] In this embodiment, parameters related to the motor's current limit may include, but are not limited to, parameters affecting the current that the motor controller can output, such as battery capacity and power electronics unit capacity. In one possible implementation, the motor controller may set the maximum permissible supply current I applied to the motor based on the battery capacity and power electronics unit capacity, which are parameters related to the motor's current limit. m .

[0044] The maximum allowable supply current I is set. mThen, the motor controller can use the set maximum allowable supply current I. m This is used to test the peak performance of the motor. The peak performance of the motor includes, but is not limited to, peak torque and peak power. Testing the peak performance of the motor may include, but is not limited to, outputting curves or distribution histograms corresponding to the peak performance of the motor, so that users can more easily view the peak performance of the motor.

[0045] For example, the peak torque curve can be formed by connecting multiple points where the horizontal axis represents the motor speed and the vertical axis represents the maximum torque value of the motor, or it can be a peak torque distribution histogram drawn based on the speed and its corresponding maximum torque value; correspondingly, the peak power curve can be formed by connecting multiple points where the horizontal axis represents the motor speed and the vertical axis represents the maximum power value of the motor, or it can be a peak power distribution histogram drawn based on the speed and its corresponding maximum power value.

[0046] In step S240, the maximum allowable supply current I is set. m During the performance testing of the motor, the motor reaches a predetermined speed n. b At that time, adjust the set maximum allowable power supply current I. m This is to reduce the speed as the motor speed increases. Step S240 corresponds to the adjustment step.

[0047] In this embodiment, the maximum allowable supply current I set according to step S220 above is... m During peak performance testing of the motor, the motor controller can acquire the motor's rotational speed n. In one possible implementation, the motor controller can acquire the motor's rotational speed via, for example, a speed sensor mounted on the motor.

[0048] The motor controller can determine whether the acquired rotational speed n has reached the predetermined rotational speed n. b In one possible implementation, the motor controller can compare the acquired rotational speed n with a predetermined rotational speed n0. b Compare; if the obtained rotational speed n is greater than or equal to the predetermined rotational speed n b Then the motor controller determines that the obtained speed n has reached the predetermined speed n. b .

[0049] Predetermined rotational speed n b The setting methods include, but are not limited to, setting based on actual test results or based on the engineer's experience. In one possible implementation, the motor speed when the actually measured copper loss density reaches its maximum allowable value can be set to a predetermined speed n. bSpecifically, if actual testing reveals that the short-term temperature rise reaches the maximum allowable value at a certain rotational speed, then the copper loss density at this point also reaches the maximum allowable value. The rotational speed at this point can then be set as a predetermined speed n. b In another possible implementation, a predetermined rotational speed set by the engineer based on experience can be obtained and used as the predetermined rotational speed n. b .

[0050] It is determined that the obtained rotational speed n has reached the predetermined rotational speed n. b In this case, it indicates that the copper loss density has reached the maximum allowable value. In this situation, the motor controller needs to reduce the set maximum allowable supply current I. m This ensures that the copper loss density remains essentially constant. In other words, under the aforementioned conditions, the motor controller can operate according to the maximum allowable supply current I set in step S220 above. m The adjustment method, which decreases as the motor speed n increases, is used to adjust the maximum allowable supply current I set in step S220 above. m Adjustments are made, and the maximum allowable supply current after adjustment is I'. m .

[0051] It should be understandable that when it is determined that the obtained rotational speed n has reached the predetermined rotational speed n... b In this case, the motor controller can reduce the maximum allowable supply current according to the motor speed n. As for how to reduce the maximum allowable supply current and / or to what value, the present invention does not impose specific restrictions. As long as the maximum allowable supply current can be reduced in a way that keeps the copper loss density basically constant, and the reduced value, it can be applied to the present invention.

[0052] In one possible implementation, the maximum permissible supply current can be reduced by: calculating the ratio of the height of the conductor in the stator slot of the motor to the skin depth; calculating a target maximum permissible supply current based on the ratio, the identifier of the conductor, and the set maximum permissible supply current; and adjusting the set maximum permissible supply current to the calculated target maximum permissible supply current, wherein the target maximum permissible supply current is less than the set maximum permissible supply current.

[0053] In this embodiment, as mentioned above, when the motor speed reaches the predetermined speed, the skin effect causes the maximum copper loss density to become inconsistent as the motor speed increases. Therefore, in order to keep the maximum copper loss density essentially constant, the skin effect needs to be considered when the motor speed reaches the predetermined speed. To this end, the motor controller can obtain the height of the conductor in the stator slot and its corresponding skin depth and calculate the ratio between the two.

[0054] Corresponding conductors are installed at corresponding positions in the stator slots. Conductors at different positions have different markings, thus the markings of the conductors also indicate their positions in the stator slots. It should be understood that the skin depth can represent the depth at which the current density in the conductor decreases to 1 / e (e is the natural base e = 2.71828183) of the current density at the surface of the conductor cross-section. This invention does not limit this, but depends on the specific circumstances.

[0055] The motor controller can calculate the reduction magnitude (also known as the reduction coefficient) based on the calculated ratio of conductor height to skin depth and conductor markings, and can apply the reduction magnitude to the maximum allowable supply current set in step S220 to reduce the maximum allowable supply current.

[0056] In one implementation, the maximum allowable supply current can be reduced by multiplying the reduction magnitude with the maximum allowable supply current set in step S220. In this case, the reduction magnitude should be less than 1. Alternatively, the maximum allowable supply current can be reduced by subtracting the reduction magnitude from the maximum allowable supply current set in step S220. Or, the maximum allowable supply current can be reduced by dividing the reduction magnitude from the maximum allowable supply current set in step S220. In this case, the reduction magnitude should be greater than 1.

[0057] Of course, it should be understood that any other suitable algorithm can be used to apply the reduction to the maximum allowable supply current set in step S220, as long as the algorithm can reduce the maximum allowable supply current.

[0058] In one possible implementation, the target maximum allowable supply current can be calculated using the following formula, based on the ratio of the conductor height to the skin depth in the stator slot of the motor, the identifier of the conductor, and the set maximum allowable supply current: Among them, I m I represents the maximum allowable supply current of the target. b The maximum allowable supply current is set, ξ represents the ratio of the conductor height to the skin depth, and N represents the conductor's identifier.

[0059] In step S260, the peak performance of the motor is tested again using the adjusted maximum permissible supply current. Step S260 corresponds to the continued testing step.

[0060] In this embodiment, before the motor speed reaches the predetermined speed, the motor controller can use the maximum allowable supply current set in step S220 to test the peak performance of the motor. When the motor speed reaches the predetermined speed, the motor controller adjusts the maximum allowable supply current set in step S220 to reduce it. Then, the motor controller can use the adjusted maximum allowable supply current to continue testing the peak performance of the motor.

[0061] The motor performance testing method of this embodiment uses a set maximum allowable supply current to test the peak performance of the motor. During this process, if the motor speed reaches a predetermined speed, the set maximum allowable supply current is reduced as the motor speed increases, and the peak performance of the motor is continued to be tested using the adjusted maximum allowable supply current. Therefore, compared with the prior art, which only considers current and / or voltage limits without considering the skin effect when testing the peak performance of the motor, this embodiment considers both current limits and the skin effect when testing the peak performance of the motor. Thus, by reducing the maximum allowable supply current applied to the motor when the motor speed reaches the predetermined speed, the maximum copper loss density can be kept essentially constant as the motor speed increases.

[0062] Figure 4 This is a schematic diagram comparing the peak performance of a motor after applying the peak performance testing method of this embodiment and related technologies. Figure 4 In this diagram, the symbols “T”, “P”, and “n” represent peak torque, peak power, and speed, respectively. The solid line represents the curve obtained by testing the peak performance of the motor using the peak performance testing method of this embodiment, and the dashed line represents the curve obtained by testing the peak performance of the motor using the existing peak performance testing method.

[0063] like Figure 4 As shown, before the motor speed reaches 5000 rpm, the peak torque obtained by the motor peak performance test method of this embodiment is basically the same as the peak torque obtained by the existing motor peak performance test method, and the peak power obtained by the motor peak performance test method of this embodiment is also basically the same as the peak power obtained by the existing motor peak performance test method. However, when the motor speed reaches 5000 rpm, at the same speed point, the peak torque obtained by the motor peak performance test method of this embodiment is less than the peak torque obtained by the existing motor peak performance test method, and the peak power obtained by the motor peak performance test method of this embodiment is also less than the peak power obtained by the existing motor peak performance test method.

[0064] Figure 5This is a schematic diagram comparing the copper loss density in the last conductor of the stator slot after applying the motor peak performance testing method of this embodiment and related technologies. Figure 5 The symbol "n" in the figure represents the rotational speed. The solid line represents the curve obtained by testing the peak performance of the motor using the peak performance test method of this embodiment, and the dashed line represents the curve obtained by testing the peak performance of the motor using the existing peak performance test method.

[0065] like Figure 5 As shown, before the motor speed reaches 5000 rpm, the copper loss density in the last conductor of the stator slot using the motor peak performance test method of this embodiment and the prior art is basically constant. However, when the motor speed reaches 5000 rpm, compared with the copper loss density in the last conductor of the stator slot using the motor peak performance test method of the prior art, which increases with the increase of speed, the copper loss density in the last conductor of the stator slot using the motor peak performance test method of this embodiment remains basically constant with the increase of speed.

[0066] In one possible implementation, the above-mentioned test setting steps may include: setting the maximum allowable supply current and the maximum allowable supply voltage of the motor; calculating the electromagnetic torque and phase voltage of the motor corresponding to each speed according to the set lead angle and current test step size; and filtering out the electromagnetic torque and phase voltage corresponding to speeds where the phase voltage exceeds the maximum allowable supply voltage.

[0067] In this embodiment, the motor controller can be adopted. Figure 1 The method shown tests the peak performance of the motor using the set maximum allowable supply current. For example, in addition to setting the maximum allowable supply current, the maximum allowable supply voltage of the motor can also be set; the lead angle and current test step size can be set; the electromagnetic torque and phase voltage of the motor corresponding to each speed can be calculated according to the set lead angle and current test step size; and speed points where the voltage exceeds the maximum allowable supply voltage can be filtered out by scanning all speed points. For a detailed description, please refer to the previous explanation of steps S110-S140, which will not be repeated here due to space limitations.

[0068] In one possible implementation, the adjustment step may include: after filtering out the electromagnetic torque and phase voltage corresponding to the rotational speed at which the phase voltage exceeds the maximum allowable supply voltage, reducing the set maximum allowable supply current as the rotational speed of the motor increases when the motor speed reaches a predetermined speed.

[0069] In this embodiment, the motor controller can, for example, filter out phase voltages exceeding the maximum allowable supply voltage U by scanning all speed points. mThe electromagnetic torque and phase voltage corresponding to the speed point are used. For the remaining speed points after filtering, the maximum allowable power supply current set in step S220 is adjusted in the manner described in step S240 above.

[0070] In one possible implementation, the continued testing step may include: generating a peak torque curve of the motor representing the peak torque performance of the motor based on the maximum electromagnetic torque (i.e., peak torque) corresponding to each remaining speed; and generating a peak power curve of the motor representing the peak power performance of the motor based on the maximum power (i.e., peak power) corresponding to each remaining speed.

[0071] In this embodiment, multiple points of peak torque corresponding to each remaining speed can be connected to form a peak torque curve; correspondingly, multiple points of peak power corresponding to each remaining speed can be connected to form a peak power curve. Users can know the peak performance of the motor based on the peak torque curve and the peak power curve.

[0072] In one possible implementation, the setting test step may include: setting the maximum allowable supply voltage and maximum allowable supply current of the motor based on the current and voltage capacity of the battery and power control unit (PEU) of the new energy vehicle. For details, please refer to the preceding description of step S110; due to space limitations, it will not be repeated here.

[0073] In one possible implementation, calculating the phase voltage corresponding to each speed of the motor includes: obtaining the D-axis output voltage and Q-axis output voltage in the rotating coordinate system corresponding to each speed of the motor; and calculating the phase voltage corresponding to that speed based on the obtained D-axis output voltage and Q-axis output voltage corresponding to each speed.

[0074] For example, the motor controller can use formulas 2 and 3 above to obtain the D-axis output voltage and Q-axis output voltage respectively, and then use formula 4 above to calculate the corresponding phase voltage.

[0075] The following description serves as a specific example of the motor peak performance testing method in this embodiment. Figure 3 This is a flowchart illustrating an example of a method for testing the peak performance of a motor according to an exemplary embodiment. Figure 3 As shown, the peak performance test method for this motor may include:

[0076] In step S310, the maximum allowable supply voltage and the maximum allowable supply current applied to the motor are defined. For details regarding this step, please refer to the preceding descriptions of steps S110 and S220; due to space limitations, they will not be repeated here.

[0077] In step S320, the lead angle and current interval are set. For details on this step, please refer to the descriptions of steps S120 and S220 above; due to space limitations, they will not be repeated here.

[0078] In step S330, the electromagnetic torque of the motor, the D-axis voltage of the motor, the Q-axis voltage of the motor, and the terminal voltage of the motor are calculated. For details on this step, please refer to the descriptions of steps S130 and S220 above, which will not be repeated here due to space limitations.

[0079] In step S340, points exceeding the maximum permissible supply voltage are filtered out. For details regarding this step, please refer to the preceding descriptions of steps S140 and S220; due to space limitations, they will not be repeated here.

[0080] In step S350, during the performance test of the motor according to the set maximum allowable supply current, when the motor speed reaches a predetermined speed, the set maximum allowable supply current is adjusted so that it decreases as the motor speed increases. For details regarding this step, please refer to the description of step S240 above; due to space limitations, it will not be repeated here.

[0081] In step S360, the maximum torque and maximum power values ​​corresponding to each motor speed are found. For details regarding this step, please refer to the previous descriptions of steps S150 and S220; due to space limitations, they will not be repeated here.

[0082] In step S370, the peak torque curve and peak power curve are output. For details regarding this step, please refer to the previous descriptions of steps S160 and S220; due to space limitations, they will not be repeated here.

[0083] By comparison Figure 1 and Figure 3 As can be seen, compared with the prior art, the motor performance testing method of this embodiment adds a step S350 in which the maximum allowable supply current is reduced as the motor speed increases when the motor speed reaches a predetermined speed. This ensures that the maximum copper loss density can remain basically constant as the motor speed increases when the motor is running at high speed, thereby avoiding the influence of the skin effect.

[0084] Figure 6 This is a block diagram illustrating a peak performance testing device for a motor according to an exemplary embodiment. This device can be applied to flat-wire motors in new energy vehicles. Figure 6 As shown, the motor peak performance testing device 600 may include a test setting module 610, an adjustment module 620, and a test continuation module 630.

[0085] The setting test module 610 is used to set the maximum allowable supply current of the motor and to test the peak performance of the motor using the set maximum allowable supply current. The adjustment module 620, connected to the setting test module 610, is used to adjust the set maximum allowable supply current so that it decreases as the motor speed increases when the motor speed reaches a predetermined speed during the performance test according to the set maximum allowable supply current. The continuation test module 630, connected to the adjustment module 620, is used to continue testing the peak performance of the motor using the adjusted maximum allowable supply current.

[0086] In one possible implementation, the adjustment module 620 is configured to: calculate the ratio of the height of the conductor in the stator slot of the motor to the skin depth; calculate a target maximum allowable power supply current based on the ratio, the identifier of the conductor, and the set maximum allowable power supply current; and adjust the set maximum allowable power supply current to the calculated target maximum allowable power supply current, wherein the target maximum allowable power supply current is less than the set maximum allowable power supply current.

[0087] In one possible implementation, the adjustment module 620 is configured to calculate the target maximum allowable supply current using the following formula, based on the ratio, the identifier of the conductor, and the set maximum allowable supply current: Among them, I m I represents the maximum allowable supply current of the target. b The maximum allowable supply current is set, ξ represents the ratio of the conductor height to the skin depth, and N represents the conductor's identifier.

[0088] In one possible implementation, the setting test module 610 is configured to: set the maximum allowable supply current and the maximum allowable supply voltage of the motor; calculate the electromagnetic torque and phase voltage of the motor corresponding to each speed according to the set lead angle and current test step size; and filter out the electromagnetic torque and phase voltage corresponding to speeds where the phase voltage exceeds the maximum allowable supply voltage.

[0089] In one possible implementation, the adjustment module 620 is configured to: after filtering out the electromagnetic torque and phase voltage corresponding to the rotational speed where the phase voltage exceeds the maximum allowable supply voltage, reduce the set maximum allowable supply current as the rotational speed of the motor increases when the motor speed reaches a predetermined speed.

[0090] In one possible implementation, the continued testing module 630 is configured to: generate a peak torque curve of the motor representing the peak torque performance of the motor based on the maximum electromagnetic torque corresponding to each remaining speed; and generate a peak power curve of the motor representing the peak power performance of the motor based on the maximum power corresponding to each remaining speed.

[0091] In one possible implementation, the setting test module 610 is configured to set the maximum allowable supply voltage and maximum allowable supply current of the motor based on the current and voltage capacity of the battery and power control unit (PEU) of the new energy vehicle.

[0092] In one possible implementation, the setting test module 610 is configured to: acquire the D-axis output voltage and Q-axis output voltage in the rotating coordinate system corresponding to each speed of the motor; and calculate the phase voltage corresponding to each speed based on the acquired D-axis output voltage and Q-axis output voltage.

[0093] Regarding the apparatus in the above embodiments, the specific manner in which each module performs its operation has been described in detail in the embodiments related to the method, and will not be elaborated upon here.

[0094] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for testing the peak performance of an electric motor, applied to flat wire motors in new energy vehicles, characterized in that, include: The test procedure is set to set the maximum allowable supply current of the motor and use the set maximum allowable supply current to test the peak performance of the motor. An adjustment step is used to adjust the set maximum allowable supply current to decrease as the motor speed increases when the motor speed reaches a predetermined speed during the performance test of the motor according to the set maximum allowable supply current. as well as The testing process continues, using the adjusted maximum permissible supply current to further test the peak performance of the motor.

2. The method for testing the peak performance of a motor according to claim 1, characterized in that, In the adjustment step, Calculate the ratio of the height of the conductor in the stator slot of the motor to the skin depth; The target maximum allowable supply current is calculated based on the ratio, the conductor identification, and the set maximum allowable supply current. The set maximum allowable power supply current is adjusted to the calculated target maximum allowable power supply current, wherein the target maximum allowable power supply current is less than the set maximum allowable power supply current.

3. The method for testing the peak performance of a motor according to claim 2, characterized in that, In the adjustment step, the target maximum allowable supply current is calculated using the following formula, based on the ratio, the conductor identification, and the set maximum allowable supply current: Among them, I m I represents the maximum allowable supply current of the target. b The maximum allowable supply current is set, ξ represents the ratio of the conductor height to the skin depth, and N represents the conductor's identifier.

4. The method for testing the peak performance of a motor according to any one of claims 1 to 3, characterized in that, The setup test steps include: Set the maximum allowable power supply current and the maximum allowable power supply voltage of the motor; Calculate the electromagnetic torque and phase voltage of the motor corresponding to each speed, based on the set lead angle and current test step size; The electromagnetic torque and phase voltage corresponding to the rotational speed at which the phase voltage exceeds the maximum allowable supply voltage are filtered out.

5. The method for testing the peak performance of a motor according to claim 4, characterized in that, The adjustment steps include: After filtering out the electromagnetic torque and phase voltage corresponding to the rotational speed where the phase voltage exceeds the maximum allowable supply voltage, the maximum allowable supply current is reduced as the rotational speed of the motor increases when the motor speed reaches the predetermined speed.

6. The method for testing the peak performance of a motor according to claim 5, characterized in that, The continued testing steps include: The peak torque curve of the motor is generated based on the maximum electromagnetic torque corresponding to each remaining rotational speed, representing the peak torque performance of the motor. The peak power curve of the motor is generated based on the maximum power corresponding to each remaining speed, representing the peak power performance of the motor.

7. The method for testing the peak performance of a motor according to claim 4, characterized in that, The setup test steps include: Based on the current and voltage capacity of the battery and power control unit (PEU) of the new energy vehicle, the maximum allowable supply voltage and maximum allowable supply current of the motor are set.

8. The method for testing the peak performance of a motor according to claim 4, characterized in that, Calculating the phase voltage corresponding to each speed of the motor includes: Obtain the D-axis output voltage and Q-axis output voltage in the rotating coordinate system corresponding to each speed of the motor; The phase voltage corresponding to each rotational speed is calculated based on the D-axis output voltage and Q-axis output voltage obtained for each rotational speed.

9. A peak performance testing device for electric motors, applied to flat wire motors in new energy vehicles, characterized in that, include: The test module is set to set the maximum allowable supply current of the motor and use the set maximum allowable supply current to test the peak performance of the motor. An adjustment module, connected to the setting test module, is used to adjust the set maximum allowable supply current so that it decreases as the motor speed increases when the motor speed reaches a predetermined speed during the performance test of the motor according to the set maximum allowable supply current. as well as The continuing test module, connected to the adjustment module, is used to continue testing the peak performance of the motor using the adjusted maximum allowable supply current.

10. The motor peak performance testing device according to claim 9, characterized in that, The adjustment module is configured as follows: Calculate the ratio of the height of the conductor in the stator slot of the motor to the skin depth; The target maximum allowable supply current is calculated based on the ratio, the conductor identification, and the set maximum allowable supply current. The set maximum allowable power supply current is adjusted to the calculated target maximum allowable power supply current, wherein the target maximum allowable power supply current is less than the set maximum allowable power supply current.

11. The motor peak performance testing device according to claim 10, characterized in that, The adjustment module is configured to calculate the target maximum allowable supply current using the following formula, based on the ratio, the conductor's identifier, and the set maximum allowable supply current: Among them, I m I represents the maximum allowable supply current of the target. b The maximum allowable supply current is set, ξ represents the ratio of the conductor height to the skin depth, and N represents the conductor's identifier.

12. The motor peak performance testing device according to any one of claims 9 to 11, characterized in that, The test module is configured as follows: Set the maximum allowable power supply current and the maximum allowable power supply voltage of the motor; Calculate the electromagnetic torque and phase voltage of the motor corresponding to each speed, based on the set lead angle and current test step size; The electromagnetic torque and phase voltage corresponding to the rotational speed at which the phase voltage exceeds the maximum allowable supply voltage are filtered out.

13. The motor peak performance testing device according to claim 12, characterized in that, The adjustment module is configured as follows: After filtering out the electromagnetic torque and phase voltage corresponding to the rotational speed where the phase voltage exceeds the maximum allowable supply voltage, the maximum allowable supply current is reduced as the rotational speed of the motor increases when the motor speed reaches the predetermined speed.

14. The motor peak performance testing device according to claim 13, characterized in that, The continued testing module is configured as follows: The peak torque curve of the motor is generated based on the maximum electromagnetic torque corresponding to each remaining rotational speed, representing the peak torque performance of the motor. The peak power curve of the motor is generated based on the maximum power corresponding to each remaining speed, representing the peak power performance of the motor.

15. The motor peak performance testing device according to claim 12, characterized in that, The test module is configured as follows: Based on the current and voltage capacity of the battery and power control unit (PEU) of the new energy vehicle, the maximum allowable supply voltage and maximum allowable supply current of the motor are set.

16. The motor peak performance testing device according to claim 12, characterized in that, The test module is configured as follows: Obtain the D-axis output voltage and Q-axis output voltage in the rotating coordinate system corresponding to each speed of the motor; The phase voltage corresponding to each rotational speed is calculated based on the D-axis output voltage and Q-axis output voltage obtained for each rotational speed.

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