A calibration test method for oil-cooled motor

Abstract

The present invention relates to the technical field of powertrain and motor calibration testing of new energy vehicles, and particularly to a calibration testing method for an oil-cooled motor. The method comprises the following steps: a first temperature sensor group for feeding back first temperature information is arranged at least one of a stator winding of the oil-cooled motor, an iron core of the stator of the oil-cooled motor, and a connecting copper bar of the stator winding; the stator, a rotor, and a rotating shaft are enclosed in a sealed space surrounded by a shell and an end cover, an oil circuit channel is arranged in the sealed space, and the oil circuit channel is externally connected to an oil pump unit; a prototype of the oil-cooled motor is manufactured, and set motor operation information controls the stator, rotor, and rotating shaft to simulate the motor operation of the oil-cooled motor; the set oil circuit operation information causes cooling oil to operate in the oil circuit channel to simulate the actual operation of the cooling oil in the cooling system of the oil-cooled motor; temperature distribution information is obtained according to the first temperature information, and it is judged according to the temperature distribution information whether the setting of the oil circuit operation information meets the design requirements.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy vehicle powertrain and motor calibration testing, and in particular to a calibration testing method for an oil-cooled motor. Background Art

[0002] Currently, the motors used in electric vehicles are primarily permanent magnet synchronous motors, and their cooling methods primarily include water cooling and oil cooling, with water cooling being the mainstream. However, with the increasing integration, high speed, high efficiency, and high power density of electric drive systems, the lower heat dissipation efficiency of water cooling can no longer meet the temperature control requirements of motors. Consequently, oil-cooled motors are gaining popularity. Unlike water-cooled motors, which only exchange heat indirectly between the stator and housing, and between the housing and cooling water, oil-cooled motors use cooling oil to directly exchange heat with the main internal heat sources of the motor (such as the stator core, stator windings, rotor core, and bearings), resulting in more effective heat dissipation.

[0003] The calibration test of the oil-cooled motor cannot be equipped with a reduction gearbox, but at the same time the circulation and closure of the oil circuit must be ensured. The existing calibration test method of the oil-cooled motor is mainly through simulation analysis and motor temperature rise test on the prototype of the oil-cooled motor. The overall cooling effect of the oil-cooled motor is evaluated according to the results of the motor temperature rise test to verify whether the design scheme of the oil-cooled motor meets the design requirements. However, the existing calibration test method of the oil-cooled motor can usually only perform an overall evaluation on whether the relevant design parameters of the cooling system of the oil-cooled motor meet the design requirements. It is difficult to separately evaluate and verify the rationality of each design parameter (such as: the total amount of cooling oil circulating in the cooling system, the flow rate of cooling oil delivered by the oil pump, the flow distribution of cooling oil delivered to the main heat source inside the motor by the cooling system, etc.). As a result, it is difficult to provide targeted guidance, verification and optimization of the relevant design parameters of the cooling system in the design scheme of the oil-cooled motor through the existing calibration test method of the oil-cooled motor. Summary of the Invention

[0004] The present invention solves the technical problem that the existing calibration and testing method of oil-cooled motors is difficult to provide targeted guidance, verification and optimization of various relevant design parameters of the cooling system in the design scheme of the oil-cooled motor by providing a calibration and testing method of the oil-cooled motor.

[0005] The technical solution adopted by the present invention is: a calibration test method for an oil-cooled motor, comprising the following steps:

[0006] Step 1: disposing a plurality of first temperature sensor groups for feeding back first temperature information at at least one of a stator winding of an oil-cooled motor, an iron core of a stator of the oil-cooled motor, and a connecting copper bar of the stator winding;

[0007] Step 2: Install the stator, rotor and rotating shaft of the oil-cooled motor in a housing used to simulate the housing of the oil-cooled motor;

[0008] Step 3: Install an end cover at one end of the housing to enclose the stator, the rotor, and the rotating shaft in a sealed space defined by the housing and the end cover. An oil passage is provided in the sealed space, and the oil passage is externally connected to an oil pump unit.

[0009] Step 4: Set the motor operation information and oil circuit operation information for calibration test;

[0010] Step 5: Based on the set motor operation information, the stator, the rotor, and the rotating shaft are controlled to simulate the motor operation of the oil-cooled motor; based on the set oil circuit operation information, the cooling oil is caused to flow in the oil circuit channel to simulate the actual operation of the cooling oil in the cooling system of the oil-cooled motor; and temperature distribution information is obtained based on the first temperature information fed back by each of the first temperature sensor groups;

[0011] Step 6: Determine whether the setting of the oil circuit operation information meets the design requirements based on the temperature distribution information; if so, return to step 4, adjust the set value of the motor operation information, and perform the next round of simulation and judgment; if not, return to step 4, adjust the set value of the oil circuit operation information, and perform the next round of simulation and judgment.

[0012] Using the calibration test method, an end cover is installed at one end of the housing, and the stator, rotor, and rotating shaft are enclosed in a sealed space defined by the housing and the end cover to produce a prototype of an oil-cooled motor. An oil channel provided in the sealed space and an oil pump unit connected to the oil channel are used to simulate the cooling system of the oil-cooled motor.

[0013] The operation of the oil-cooled motor under specific operating conditions (such as, but not limited to, rated torque, rated speed, peak speed, and peak power) is simulated by controlling the stator, the rotor, and the rotating shaft based on the set motor operation information; and the operation of the stator, the rotor, and the rotating shaft is simulated by adjusting the set values ​​of the motor operation information.

[0014] The cooling oil is caused to circulate in the oil passage by the set oil circuit operation information to simulate the actual operation of the cooling oil in the cooling system of the oil-cooled motor; thereby, the actual operation of the cooling system of the oil-cooled motor under various working conditions is simulated by the operation of the prototype of the oil-cooled motor;

[0015] In the above simulation process, the oil circuit operation information includes one or more of the various design parameters of the cooling system of the above-mentioned oil-cooled motor (such as: the total amount of cooling oil circulating in the cooling system, the output flow rate of the cooling oil delivered by the oil pump, the aperture of the oil inlet of the motor housing, the aperture of the oil outlet of the motor housing, the aperture of the oil injection hole on the oil injection ring, the number of oil injection holes on the oil injection ring, the flow distribution of the cooling oil delivered to the main heat source inside the motor by the cooling system, etc.); and in the step 1, according to the needs of analysis and verification, a plurality of the first temperature sensor groups are set at at least one of the stator winding of the oil-cooled motor, the iron core of the stator of the oil-cooled motor and the connecting copper bar of the stator winding to obtain temperature distribution information, and the actual cooling effect of the cooling oil in the simulation process is analyzed and verified; the calibration test method of the oil-cooled motor can be used to achieve targeted guidance, verification and optimization of the various relevant design parameters of the cooling system in the design scheme of the oil-cooled motor.

[0016] Furthermore, the oil circuit operation information includes the total amount of the cooling oil circulating in the oil circuit channel and the output flow rate of the oil pump unit.

[0017] Among them, the corresponding setting of the motor operation information satisfies the ability to control the stator, the rotor and the rotating shaft to simulate the operation of the oil-cooled motor under specific working conditions (for example, but not limited to: rated torque, rated speed, peak speed, peak power, etc.); and can adjust the set value of the motor operation information to make the stator, the rotor and the rotating shaft simulate the operation of the oil-cooled motor under different working conditions (for example, but not limited to: the motor operation information includes the speed and torque of the rotating shaft, or the motor operation information includes the input voltage and input current of the stator winding).

[0018] Furthermore, the motor operation information includes the rotation speed and torque of the shaft.

[0019] Furthermore, step 5 includes the following sub-steps:

[0020] S1: controlling the oil pump unit based on the set oil circuit operation information to pump the cooling oil into the oil circuit channel and circulate the cooling oil in the oil circuit channel;

[0021] S2: controlling the stator, the rotor, and the rotating shaft to operate based on the set motor operation information, so as to increase the temperature of the stator winding, the stator core, and the connecting copper bar;

[0022] S3: After the fluctuation values ​​of the first temperature information fed back by each first temperature sensor group within a specified time are all smaller than a set value, the first temperature information obtained at this time is matched with the arrangement positions of each first temperature sensor group to obtain the temperature distribution information.

[0023] When the fluctuation values ​​of the first temperature information fed back by the first temperature sensor group within a specified time are all smaller than the set value, that is, when the location where the first temperature sensor group is provided reaches thermal equilibrium.

[0024] Furthermore, the oil pump unit includes an oil pipe, an oil cooler mounted on the oil pipe, and an oil pump. The oil pump is integrated with an oil collecting box, the oil collecting box is used to store the cooling oil, and the oil pump is used to transport the cooling oil in the oil collecting box to the oil cooler for cooling, and then pump it into the oil channel, and then extract the cooling oil in the oil channel into the oil collecting box;

[0025] The oil pipe is provided with a flow meter, which is used to obtain flow information of the cooling oil delivered by the oil pump. The oil cooler is provided with a second temperature sensor, which is used to obtain second temperature information of the cooling oil after being cooled by the oil cooler. The oil collecting box and the oil cooler are both provided with visual windows.

[0026] Furthermore, in the step S1, after the cooling oil circulates in the oil channel, it is determined whether the cooling oil circulates stably in the oil channel. If so, the process proceeds to S2, otherwise, S1 is repeated.

[0027] The method for determining whether the cooling oil circulates stably in the oil passage comprises the following sub-steps:

[0028] S101: adding a corresponding amount of cooling oil into the oil collecting box according to the total oil amount in the oil circuit operation information;

[0029] S102: starting the oil pump and the oil cooler, and controlling the speed of the oil pump so that the flow rate information fed back by the flow meter is consistent with the flow rate in the oil circuit operation information;

[0030] S103: Detecting the second temperature information to determine whether the temperature of the cooling oil after cooling by the oil cooler is within a first range; if so, proceeding to S104; if not, returning to S103;

[0031] S104: Determine through the visual window whether the cooling oil circulation is interrupted and whether the oil has air entrainment; if the cooling oil circulation is not interrupted and the oil has no air entrainment, determine that the cooling oil is circulating stably in the oil channel; otherwise, determine that the cooling oil is not circulating stably in the oil channel.

[0032] Furthermore, in step 6, the method for judging whether the setting of the oil circuit operation information meets the design requirements based on the temperature distribution information includes: judging whether the temperatures fed back by each of the first temperature sensor groups are lower than the preset temperatures corresponding to the positions where each of the first temperature sensor groups is set based on the temperature distribution information; if they are all lower than the preset temperatures, it is judged that the setting of the oil circuit operation information meets the design requirements; otherwise, it is judged that the setting of the oil circuit operation information does not meet the design requirements.

[0033] Furthermore, the oil circuit operation information includes the number of the oil injection holes of the oil injection ring and the aperture of each of the oil injection holes.

[0034] Correspondingly, the setting of the motor operation information satisfies the requirement to control the stator, the rotor and the rotating shaft to simulate the operation of the oil-cooled motor under specific working conditions (for example, but not limited to: rated torque, rated speed, peak speed, peak power, etc.); and the stator, the rotor and the rotating shaft can simulate the operation of the oil-cooled motor under different working conditions by adjusting the set value of the motor operation information (for example, but not limited to: the motor operation information includes the speed and torque of the rotating shaft, or the motor operation information includes the input voltage and input current of the stator winding).

[0035] Furthermore, in step 1, the plurality of first temperature sensor groups provided on the stator winding of the oil-cooled motor include: a plurality of temperature sensors provided on the plug-in ends of the stator winding, a plurality of temperature sensors provided on the welding ends of the stator winding, and a plurality of temperature sensors provided on the connecting copper bars of the welding ends of the stator winding;

[0036] In step 2, the housing is sleeved outside the iron core of the stator and has an interference fit with the iron core;

[0037] In step 3, the oil injection ring is further installed between the end cover and the iron core.

[0038] Furthermore, the oil passage comprises a plurality of annular oil grooves opened in the circumferential direction and a plurality of axial oil grooves opened in the axial direction on the inner circumferential surface of the housing, the annular oil grooves and the axial oil grooves being in communication, an oil inlet and an oil outlet of the oil passage being provided on the housing or the end cover, the oil pump unit delivering the cooling oil to the annular oil grooves and the axial oil grooves through the oil inlet, and the oil pump unit withdrawing the cooling oil in the oil passage through the oil outlet;

[0039] The axial oil groove and the annular oil groove are used to cooperate with the outer circumferential surface of the iron core. The axial ends of the axial oil groove respectively extend beyond the axial ends of the iron core. The end of the axial oil groove away from the end cover is used to transport the cooling oil to the end of the stator winding away from the end cover; the end of the axial oil groove close to the end cover forms an oil cavity with the housing, the oil spray ring, and the iron core. The oil spray ring is provided with a plurality of oil spray holes distributed along the circumferential direction. One end of the oil spray hole is connected to the oil cavity, and the other end of the oil spray hole faces the end of the stator winding close to the end cover.

[0040] By making the axial ends of the axial oil groove extend beyond the axial ends of the iron core, the end of the axial oil groove away from the end cover is used to transport the cooling oil to the end of the stator winding away from the end cover; the end of the axial oil groove close to the end cover forms an oil cavity with the housing, the oil spray ring, and the iron core, so that the cooling oil can be transported to the end of the stator winding close to the end cover through the oil spray holes on the oil spray ring;

[0041] At the same time, the axial thickness of the oil injection ring can be adjusted so that the housing can be installed and matched with various stators with different axial lengths at the same radius.

[0042] Furthermore, in step 6, the method for judging whether the setting of the oil circuit operation information meets the design requirements based on the temperature distribution information includes: judging whether the temperature difference between the average temperature of the plug end and the average temperature of the welding end is greater than the preset temperature difference based on the temperature distribution information; if it is greater than the preset temperature difference, judging that the setting of the oil circuit operation information does not meet the design requirements; otherwise, judging that the setting of the oil circuit operation information meets the design requirements.

[0043] The temperature distribution information determines that if the temperature difference between the average temperature of the plug-in end and the average temperature of the welding end is greater than the preset temperature difference, it means that the distribution ratio of the cooling oil flow to the plug-in end and the welding end in the oil circuit channel cannot meet the design requirements. The above-mentioned distribution ratio of the cooling oil flow can be adjusted by adjusting the number of the oil injection holes of the oil injection ring and the aperture of each of the oil injection holes. Therefore, it can be determined that the setting of the number of the oil injection holes and the aperture of each of the oil injection holes (that is, the oil circuit operation information) does not meet the design requirements.

[0044] Furthermore, after determining that the setting of the oil circuit operation information does not meet the design requirements, return to step 4, replace the oil injection ring, adjust the set value of the number of the oil injection holes and the aperture of each oil injection hole in the oil circuit operation information, and perform the next round of simulation and judgment.

[0045] By replacing the oil injection ring, the number of the oil injection holes and the set value of the aperture of each oil injection hole in the oil circuit operation information are adjusted, and then the distribution ratio of the cooling oil flow of the oil circuit channel to the plug-in end and the welding end is adjusted. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 This is a structural diagram of the assembly of the stator, rotor, shaft, housing and end cover in the present invention;

[0047] Figure 2 Schematic diagram of the assembly of the housing, end cover and oil pump unit in the present invention;

[0048] Figure 3 Schematic diagram of the structure of the end cover in the present invention;

[0049] Figure 4 for Figure 3 AA cross-section of

[0050] Figure 5 This is a diagram showing the arrangement of temperature sensors at the wire ends of the stator windings in Example 2;

[0051] Figure 6 This is a diagram showing the arrangement of temperature sensors at the welding ends of the stator windings in Example 2;

[0052] Figure 7 It is a structural schematic diagram of the oil pump in the present invention;

[0053] Figure 8 Schematic diagram of the structure of the oil injection ring in Example 2;

[0054] Among them, 1 is the stator, 2 is the rotor, 3 is the shaft, 4 is the housing, 5 is the end cover, 6 is the oil pump unit, 7 is the oil injection ring, and 8 is the first temperature sensor group;

[0055] 11—stator winding, 12—iron core;

[0056] 111—Connecting copper busbar;

[0057] 41—axial oil groove, 42—oil inlet, 43—annular oil groove;

[0058] 51—oil outlet, 52—wire outlet hole, 53—bearing chamber oil channel;

[0059] 61—Oil pipe, 62—Oil cooler, 63—Oil pump;

[0060] 611—Flow meter;

[0061] 621—second temperature sensor, 622—oil circuit base;

[0062] 631—Oil collecting box, 632—Visual window, 633—Oil filter;

[0063] 71—Fuel injection hole. DETAILED DESCRIPTION

[0064] The following is a clear and complete description of the technical solutions in the embodiments of the present invention with reference to the accompanying drawings:

[0065] Example 1

[0066] This embodiment 1 provides a calibration test method for an oil-cooled motor, comprising the following steps:

[0067] Step 1: a plurality of first temperature sensor groups 8 for feeding back first temperature information are provided at at least one of the stator winding 11 of the oil-cooled motor, the iron core 12 of the stator 1 of the oil-cooled motor, and the connecting copper bar 111 of the stator winding 11;

[0068] Step 2: If Figure 1 As shown, the stator 1, rotor 2 and shaft 3 of the oil-cooled motor are installed in a housing 4 for simulating the housing of the oil-cooled motor;

[0069] Step 3: If Figure 1 and Figure 2 As shown, an end cover 5 is installed at one end of the housing 4, enclosing the stator 1, rotor 2 and rotating shaft 3 in a sealed space surrounded by the housing 4 and the end cover 5. An oil passage is provided in the sealed space, and the oil passage is externally connected to an oil pump unit 6;

[0070] Step 4: Set the motor operation information and oil circuit operation information for calibration test;

[0071] Step 5: Based on the set motor operation information, the stator 1, rotor 2, and shaft 3 are controlled to simulate the operation of the oil-cooled motor. Simultaneously, based on the set oil circuit operation information, the cooling oil is caused to flow in the oil circuit to simulate the actual operation of the cooling oil in the cooling system of the oil-cooled motor. Temperature distribution information is obtained through the first temperature information fed back by each first temperature sensor group 8.

[0072] Step 6: Determine whether the setting of the oil circuit operation information meets the design requirements based on the temperature distribution information; if so, return to step 4, adjust the set value of the motor operation information, and perform the next round of simulation and judgment; if not, return to step 4, adjust the set value of the oil circuit operation information, and perform the next round of simulation and judgment.

[0073] Using the calibration test method described above, an end cover 5 is installed at one end of a housing 4, enclosing the stator 1, rotor 2, and rotating shaft 3 within a sealed space formed by the housing 4 and the end cover 5 to create a prototype of an oil-cooled motor. An oil channel provided within the sealed space and an oil pump unit 6 connected externally to the channel are used to simulate the cooling system of an oil-cooled motor.

[0074] By controlling the stator 1, rotor 2, and shaft 3 based on the set motor operation information to simulate the operation of the oil-cooled motor under specific working conditions (such as but not limited to: rated torque, rated speed, peak speed, peak power, etc.); by adjusting the set values ​​of the motor operation information, the stator 1, rotor 2, and shaft 3 simulate the operation of the oil-cooled motor under different working conditions;

[0075] The cooling oil is made to run in the oil channel by the set oil circuit operation information to simulate the actual operation of the cooling oil in the cooling system of the oil-cooled motor; and the actual operation of the cooling system of the oil-cooled motor under various working conditions is simulated by the operation of the oil-cooled motor prototype.

[0076] In the above simulation process, the oil circuit operation information includes one or more of the various design parameters of the cooling system of the above-mentioned oil-cooled motor (such as: the total amount of cooling oil circulating in the cooling system, the output flow rate of the cooling oil delivered by the oil pump, the aperture of the oil inlet of the motor housing, the aperture of the oil outlet of the motor housing, the aperture of the oil injection hole on the oil injection ring, the number of oil injection holes on the oil injection ring, the flow distribution of the cooling oil delivered to the main heat source inside the motor by the cooling system, etc.); and in step 1, according to the needs of analysis and verification, a plurality of first temperature sensor groups 8 are set at at least one of the stator winding 11 of the oil-cooled motor, the iron core 12 of the stator 1 of the oil-cooled motor, and the connecting copper bar 111 of the stator winding 11 to obtain temperature distribution information, and analyze and verify the actual cooling effect of the cooling oil in the simulation process; then, through the calibration test method of the oil-cooled motor, targeted guidance, verification and optimization of the various relevant design parameters of the cooling system in the design scheme of the oil-cooled motor can be achieved.

[0077] The oil circuit operation information includes the total amount of cooling oil circulating in the oil circuit channel and the output flow rate of the oil pump unit 6 .

[0078] Correspondingly, the setting of the motor operation information satisfies the ability to control the stator 1, rotor 2 and shaft 3 to simulate the operation of the oil-cooled motor under specific working conditions (for example, but not limited to: rated torque, rated speed, peak speed, peak power, etc.); and can adjust the set values ​​of the motor operation information to make the stator 1, rotor 2 and shaft 3 simulate the operation of the oil-cooled motor under different working conditions (for example, but not limited to: the motor operation information includes the speed and torque of the shaft 3, or the motor operation information includes the input voltage and input current of the stator winding 11).

[0079] In the first embodiment, the motor operation information includes the rotation speed and torque of the rotating shaft 3 .

[0080] Wherein, step 5 includes the following sub-steps:

[0081] S1: Based on the set oil circuit operation information (the total amount of cooling oil circulating in the oil circuit and the output flow rate of the oil pump unit 6), the oil pump unit 6 is controlled to pump the cooling oil into the oil circuit and ensure that the cooling oil circulates stably in the oil circuit;

[0082] S2: Based on the set motor operation information, the stator 1, the rotor 2 and the rotating shaft 3 are controlled to operate so as to heat the connecting copper bar 111, the stator winding 11 and the iron core 12;

[0083] S3: After the fluctuation values ​​of the first temperature information fed back by each first temperature sensor group within a specified time are all smaller than the set value, the first temperature information obtained at this time is matched with the arrangement positions of each first temperature sensor group to obtain temperature distribution information.

[0084] When the fluctuation values ​​of the first temperature information fed back by the first temperature sensor group within the prescribed time are all smaller than the set value, that is, when the portion where the first temperature sensor group 8 is provided reaches thermal equilibrium.

[0085] Among them, such as Figure 2 and Figure 7 As shown, the oil pump unit 6 includes an oil pipe 61, an oil cooler 62 mounted on the oil pipe 61, and an oil pump 63. The oil pump 63 is integrated with an oil collecting box 631, which is used to store cooling oil. The oil pump 63 is used to transport the cooling oil in the oil collecting box 631 to the oil cooler 62 for cooling, and then pump it into the oil channel, and then extract the cooling oil in the oil channel into the oil collecting box 631.

[0086] Preferably, in this embodiment 1, the oil pump 63 is further provided with an oil filter 633. The oil pump 63 delivers the cooling oil in the oil collecting box 631 to the oil filter 633 for filtration, and then delivers it to the oil cooler 62 for cooling. The cooling oil is then pumped into the oil passage, and the cooling oil in the oil passage is extracted into the oil collecting box 631, so that the cooling oil circulates in the oil passage.

[0087] like Figure 2 As shown, the oil pipe 61 is provided with a flow meter 611 for obtaining flow information of the cooling oil delivered by the oil pump 63. The oil cooler 62 is provided with a second temperature sensor 621 for obtaining second temperature information of the cooling oil after being cooled by the oil cooler 62. The oil collecting box 631 and the oil cooler 62 are both provided with a visual window, which is sealed by a transparent acrylic plate.

[0088] In this embodiment 1, a visual window 632 is provided on the oil collecting box 631, and the visual window 632 is sealed by a transparent acrylic plate; an oil circuit base 622 is provided on the oil cooler 62, and the oil circuit base 622 is made of a transparent acrylic plate and serves as a visual window of the oil cooler 62;

[0089] The above step S1 includes the following sub-steps:

[0090] S101: Add a corresponding amount of cooling oil into the oil collecting box 631 based on the total oil amount in the oil circuit operation information (the total amount of cooling oil circulating in the oil circuit channel and the output flow rate of the oil pump unit 6);

[0091] S102: Turn on the oil pump 63 and the oil cooler 62, and control the speed of the oil pump 63 so that the flow rate information fed back by the flow meter 611 is consistent with the flow rate in the oil circuit operation information (the total amount of cooling oil circulating in the oil circuit channel and the output flow rate of the oil pump unit 6);

[0092] S103: Detect the second temperature information to determine whether the temperature of the cooling oil after cooling by the oil cooler 62 is within the first range; if so, proceed to S104; if not, return to S103;

[0093] S104: Through the visual windows (i.e., the visual window 632 and the oil circuit base 622), determine whether the cooling oil circulation is interrupted and whether there is air entrainment in the oil; if the cooling oil circulation is not interrupted and there is no air entrainment in the oil, it is determined that the cooling oil is circulating stably in the oil circuit channel.

[0094] Among them, in step 6, the method for judging whether the setting of the oil circuit operation information (the total amount of cooling oil circulating in the oil circuit channel and the output flow rate of the oil pump unit 6) meets the design requirements based on the temperature distribution information includes: judging whether the temperatures fed back by each first temperature sensor group 8 are all lower than the preset temperature corresponding to the position where each first temperature sensor group 8 is set based on the temperature distribution information; if they are all lower than the preset temperature, it is judged that the setting of the oil circuit operation information (the total amount of cooling oil circulating in the oil circuit channel and the output flow rate of the oil pump unit 6) meets the design requirements; otherwise, it is judged that the setting of the oil circuit operation information (the total amount of cooling oil circulating in the oil circuit channel and the output flow rate of the oil pump unit 6) does not meet the design requirements.

[0095] Example 2:

[0096] This embodiment 2 is implemented based on the calibration test method for the oil-cooled motor provided in embodiment 1.

[0097] The difference from the first embodiment is that in the second embodiment, the oil circuit operation information includes the number of the oil injection holes 71 of the oil injection ring 7 and the hole diameter of each oil injection hole 71 .

[0098] Correspondingly, the setting of the motor operation information satisfies the ability to control the stator 1, rotor 2 and shaft 3 to simulate the operation of the oil-cooled motor under specific working conditions (for example, but not limited to: rated torque, rated speed, peak speed, peak power, etc.); and can adjust the set values ​​of the motor operation information to make the stator 1, rotor 2 and shaft 3 simulate the operation of the oil-cooled motor under different working conditions (for example, but not limited to: the motor operation information includes the speed and torque of the shaft 3, or the motor operation information includes the input voltage and input current of the stator winding 11).

[0099] In this second embodiment, the motor operation information includes the rotation speed and torque of the rotating shaft 3 .

[0100] like Figure 5 and Figure 6 As shown, in this embodiment 2, in step 1, the plurality of first temperature sensor groups 8 provided on the stator winding of the oil-cooled motor include: a plurality of temperature sensors provided on the plug-in ends of the stator winding 11, a plurality of temperature sensors provided on the welding ends of the stator winding 11, and a plurality of temperature sensors provided on the connecting copper bars 111 of the welding ends of the stator winding 11;

[0101] in, Figure 5 and Figure 6 The above description only provides a setting scheme for the setting position of the first temperature sensor group 8, and does not constitute a limitation on the protection scope of the present invention.

[0102] like Figure 1 As shown, in step 2, the housing 4 is sleeved outside the iron core 12 of the stator 1 and is interference fit with the iron core 12;

[0103] like Figure 1 As shown, in step 3, an oil injection ring 7 is also installed between the end cover 5 and the iron core 12;

[0104] like Figure 1 、 Figure 2 and Figure 3 As shown, the oil passage comprises a plurality of annular oil grooves 43 opened along the circumferential direction on the inner circumferential surface of the housing 4 and a plurality of axial oil grooves 41 opened along the axial direction. The annular oil grooves 43 are connected to the axial oil grooves 41. The oil inlet 42 and the oil outlet 51 of the oil passage are provided on the housing 4 or the end cover 5 (in this embodiment 2, as shown in FIG. Figure 1 、 Figure 2 and Figure 3 As shown, the oil inlet 42 is provided on the housing 4, and the oil outlet 51 is provided on the end cover 5. The oil pump unit 6 delivers the cooling oil to the annular oil groove 43 and the axial oil groove 41 through the oil inlet 42, and the oil pump unit 6 withdraws the cooling oil in the oil passage through the oil outlet 51.

[0105] like Figure 1As shown, the axial oil groove 41 and the annular oil groove 43 are used to cooperate with the outer circumferential surface of the iron core 12. The axial ends of the axial oil groove 41 extend beyond the axial ends of the iron core 12. The end of the axial oil groove 41 away from the end cover 5 is used to transport cooling oil to the end of the stator winding 11 away from the end cover 5 (in this embodiment 2, that is, the welded end of the stator winding 11). The end of the axial oil groove 41 close to the end cover 5, the housing 4, the oil injection ring 7, and the iron core 12 form an oil chamber.

[0106] like Figure 8 As shown, a plurality of oil injection holes 71 are distributed circumferentially on the oil injection ring 7. One end of the oil injection hole 71 is connected to the oil chamber, and the other end of the oil injection hole 71 faces one end of the stator winding 11 close to the end cover 5 (in this embodiment 2, that is, the wire insertion end of the stator winding 11).

[0107] By ensuring that both axial ends of the axial oil groove 41 extend beyond both axial ends of the iron core 12, the end of the axial oil groove 41 away from the end cover is used to deliver cooling oil to the end of the stator winding 11 away from the end cover 5 (in this embodiment 2, that is, the welded end of the stator winding 11). The end of the axial oil groove 41 near the end cover 5, together with the housing 4, the oil injection ring 7, and the iron core 12, forms an oil chamber, which allows cooling oil to be delivered to the end of the stator winding 11 near the end cover 5 (in this embodiment 2, that is, the wire insertion end of the stator winding 11) through the oil injection holes 71 on the oil injection ring 7.

[0108] At the same time, the axial thickness of the oil injection ring 7 can be adjusted so that the housing 4 can be installed and matched with various stators 1 with different axial lengths at the same radius.

[0109] Among them, in step 6, the method for judging whether the setting of the oil circuit operation information (the number of the oil injection holes 71 of the oil injection ring 7 and the aperture of each oil injection hole 71) meets the design requirements according to the temperature distribution information includes: judging whether the temperature difference between the average temperature of the plug-in end of the stator winding 11 and the average temperature of the welding end of the stator winding 11 is greater than the first preset temperature difference according to the temperature distribution information; if it is greater than the first preset temperature difference, judging that the setting of the oil circuit operation information (the number of the oil injection holes 71 of the oil injection ring 7 and the aperture of each oil injection hole 71) does not meet the design requirements; otherwise, judging that the setting of the oil circuit operation information (the number of the oil injection holes 71 of the oil injection ring 7 and the aperture of each oil injection hole 71) meets the design requirements.

[0110] According to the above method, when it is determined through the temperature distribution information that the temperature difference between the average temperature of the plug-in end and the average temperature of the welding end is greater than the first preset temperature difference, it means that the distribution ratio of the cooling oil flow to the plug-in end and the welding end in the oil channel cannot meet the design requirements, and the above-mentioned distribution ratio of the cooling oil flow can be adjusted by adjusting the number of the oil injection holes 71 of the oil injection ring 7 and the aperture of each oil injection hole 71, so it can be determined that the setting of the number of the oil injection holes 71 and the aperture of each oil injection hole 71 (that is, the oil circuit operation information) does not meet the design requirements.

[0111] Among them, in step 6, the method of judging whether the setting of the oil circuit operation information (the number of the oil injection holes 71 of the oil injection ring 7 and the aperture of each oil injection hole 71) meets the design requirements based on the temperature distribution information also includes: judging whether the temperature difference between the maximum temperature of the plug-in end of the stator winding 11 and the maximum temperature of the welding end of the stator winding 11 is greater than the second preset temperature difference based on the temperature distribution information; if it is greater than the second preset temperature difference, judging that the setting of the oil circuit operation information (the number of the oil injection holes 71 of the oil injection ring 7 and the aperture of each oil injection hole 71) does not meet the design requirements; otherwise, judging that the setting of the oil circuit operation information (the number of the oil injection holes 71 of the oil injection ring 7 and the aperture of each oil injection hole 71) meets the design requirements.

[0112] According to the above method, when it is determined through the temperature distribution information that the temperature difference between the maximum temperature of the plug-in end and the maximum temperature of the welding end is greater than the second preset temperature difference, it means that the distribution ratio of the cooling oil flow to the plug-in end and the welding end in the oil circuit channel cannot meet the design requirements, and the above-mentioned distribution ratio of the cooling oil flow can be adjusted by adjusting the number of the oil injection holes 71 of the oil injection ring 7 and the aperture of each oil injection hole 71, so it can be determined that the setting of the number of the oil injection holes 71 and the aperture of each oil injection hole 71 (that is, the oil circuit operation information) does not meet the design requirements.

[0113] Among them, after determining that the setting of the oil circuit operation information does not meet the design requirements, return to step 4, replace the injection ring 7, and adjust the set values ​​of the number of injection holes 71 and the aperture of each injection hole 71 in the oil circuit operation information to perform the next round of simulation and judgment.

[0114] By replacing the oil injection ring 7, the number of oil injection holes 71 in the oil circuit operation information and the set value of the aperture of each oil injection hole 71 are adjusted, thereby adjusting the distribution ratio of the oil circuit channel to the wiring end and the welding end of the cooling oil flow.

[0115] Preferably, in this embodiment 2, Figure 3 As shown, a wire outlet hole 52 is provided on the upper portion of the end cover 5 for the outlet of the first temperature sensor group 8 which is arranged at one end of the stator winding 11 close to the end cover 5 (in this embodiment 2, that is, the plug-in end of the stator winding 11). Since the wire outlet hole 52 is provided on the upper portion of the end cover 5, it will not cause the cooling oil to flow out.

[0116] Preferably, in this embodiment 2, Figure 1 、 Figure 3 and Figure 4 As shown, a bearing chamber 53 for installing the rotating shaft 3 and the bearing is opened on the end cover 5, and a bearing chamber oil channel 54 is opened in the end cover 5. One end of the bearing chamber oil channel 54 is connected to the oil inlet 42, and the other end of the bearing chamber oil channel 54 is connected to the bearing chamber 53. By providing the bearing chamber oil channel 54, part of the cooling oil can be transported to the bearing chamber 53 to cool the bearing in the bearing chamber 53 for connecting the rotating shaft 3 and the end cover 5.

[0117] The oil-cooled motor calibration test method provided by the present invention has at least the following technical effects or advantages:

[0118] 1. By making the oil circuit operation information include one or more of the design parameters of the cooling system of the above-mentioned oil-cooled motor (such as: the total amount of cooling oil circulating in the cooling system, the output flow rate of the cooling oil delivered by the oil pump, the aperture of the oil inlet of the motor housing, the aperture of the oil outlet of the motor housing, the aperture of the oil injection hole on the oil injection ring, the number of oil injection holes on the oil injection ring, the flow distribution of the cooling oil delivered to the main heat source inside the motor by the cooling system, etc.); and in step 1, according to the needs of analysis and verification, a plurality of first temperature sensor groups 8 are set at at least one of the stator winding 11 of the oil-cooled motor, the iron core 12 of the stator 1 of the oil-cooled motor, and the connecting copper bar 111 of the stator winding 11 to obtain temperature distribution information, and analyze and verify the actual cooling effect of the cooling oil in the simulation process; then, through the calibration test method of the oil-cooled motor, targeted guidance, verification and optimization of the relevant design parameters of the cooling system in the design scheme of the oil-cooled motor can be achieved.

[0119] 2. By setting up visual windows (i.e., visual window 632 and oil circuit base 622), it is possible to determine whether the cooling oil circulation is interrupted and whether the oil contains air; thereby determining whether the cooling oil circulates stably in the oil circuit.

[0120] 3. After the oil circuit operation information is set, according to the needs of analysis and verification, multiple first temperature sensor groups 8 are correspondingly set at at least one of the stator winding 11 of the oil-cooled motor, the iron core 12 of the stator 1 of the oil-cooled motor, and the connecting copper bar 111 of the stator winding 11, so that the obtained temperature distribution information is more targeted for analyzing and verifying the set oil circuit operation information.

[0121] 4. By providing a bearing chamber oil passage 54 , part of the cooling oil can be delivered to the bearing chamber 53 to cool the bearing in the bearing chamber 53 that is used to connect the rotating shaft 3 and the end cover 5 .

[0122] 5. By making the axial ends of the axial oil groove 41 extend beyond the axial ends of the iron core 12, the end of the axial oil groove 41 away from the end cover is used to transport cooling oil to the end of the stator winding 11 away from the end cover 5; the end of the axial oil groove 41 close to the end cover 5 forms an oil chamber with the housing 4, the oil injection ring 7, and the iron core 12, so as to transport the cooling oil to the end of the stator winding 11 close to the end cover 5 through the oil injection holes 71 on the oil injection ring 7; at the same time, by adjusting the axial thickness of the oil injection ring 7, the housing 4 can be installed and matched with various stators 1 with different axial lengths at the same radius, thereby improving the applicability of the housing 4 and the end cover 5, reducing development costs, and shortening the development cycle.

[0123] The above are only specific application examples of the present invention and do not constitute any limitation to the protection scope of the present invention. Any technical solutions formed by equivalent transformation or equivalent replacement shall fall within the protection scope of the present invention.

Claims

1. A calibration test method for an oil-cooled motor, characterized in that: The following steps are involved: Step 1: disposing a plurality of first temperature sensor groups for feeding back first temperature information at at least one of a stator winding of an oil-cooled motor, an iron core of a stator of the oil-cooled motor, and a connecting copper bar of the stator winding; Step 2: Install the stator, rotor and rotating shaft of the oil-cooled motor in a housing used to simulate the housing of the oil-cooled motor; Step 3: Install an end cover at one end of the housing to enclose the stator, the rotor, and the rotating shaft in a sealed space defined by the housing and the end cover. An oil passage is provided in the sealed space, and the oil passage is externally connected to an oil pump unit. Step 4: Set the motor operation information and oil circuit operation information for calibration test; Step 5: Based on the set motor operation information, the stator, the rotor, and the rotating shaft are controlled to simulate the motor operation of the oil-cooled motor; Based on the set oil circuit operation information, the cooling oil is caused to circulate in the oil circuit channel to simulate the actual operation of the cooling oil in the cooling system of the oil-cooled motor; and the temperature distribution information is obtained through the first temperature information fed back by each of the first temperature sensor groups; Step 6: Determine whether the setting of the oil circuit operation information meets the design requirements based on the temperature distribution information; if so, return to step 4, adjust the setting value of the motor operation information, and perform the next round of simulation and judgment; if not, return to step 4, adjust the setting value of the oil circuit operation information, and perform the next round of simulation and judgment; The oil circuit operation information includes the total amount of the cooling oil circulating in the oil circuit channel and the output flow rate of the oil pump unit; The step 5 includes the following sub-steps: S1: controlling the oil pump unit based on the set oil circuit operation information to pump the cooling oil into the oil circuit channel and circulate the cooling oil in the oil circuit channel; S2: controlling the stator, the rotor, and the rotating shaft to operate based on the set motor operation information, so as to increase the temperature of the stator winding, the stator core, and the connecting copper bar; S3: After the fluctuation values ​​of the first temperature information fed back by each first temperature sensor group within a specified time are all smaller than a set value, the first temperature information obtained at this time is matched with the arrangement positions of each first temperature sensor group to obtain the temperature distribution information.

2. The calibration test method for an oil-cooled motor according to claim 1, characterized in that: The oil pump unit includes an oil pipe, an oil cooler mounted on the oil pipe, and an oil pump. The oil pump is integrated with an oil collecting box, the oil collecting box is used to store the cooling oil, and the oil pump is used to transport the cooling oil in the oil collecting box to the oil cooler for cooling, and then pump it into the oil channel, and then extract the cooling oil in the oil channel into the oil collecting box. The oil pipe is provided with a flow meter, which is used to obtain flow information of the cooling oil delivered by the oil pump. The oil cooler is provided with a second temperature sensor, which is used to obtain second temperature information of the cooling oil after being cooled by the oil cooler. The oil collecting box and the oil cooler are both provided with visual windows.

3. The calibration test method for an oil-cooled motor according to claim 2, characterized in that: In the step S1, after the cooling oil circulates in the oil channel, it is determined whether the cooling oil circulates stably in the oil channel. If so, the process proceeds to S2, otherwise, S1 is repeated. The method for determining whether the cooling oil circulates stably in the oil passage comprises the following sub-steps: S101: adding a corresponding amount of cooling oil into the oil collecting box according to the total oil amount in the oil circuit operation information; S102: starting the oil pump and the oil cooler, and controlling the speed of the oil pump so that the flow rate information fed back by the flow meter is consistent with the output flow rate in the oil circuit operation information; S103: Detecting the second temperature information to determine whether the temperature of the cooling oil after cooling by the oil cooler is within a first range; if so, proceeding to S104; if not, returning to S103; S104: Determine through the visual window whether the cooling oil circulation is interrupted and whether the oil has air entrainment; if the cooling oil circulation is not interrupted and the oil has no air entrainment, determine that the cooling oil is circulating stably in the oil channel; otherwise, determine that the cooling oil is not circulating stably in the oil channel.

4. The calibration test method for an oil-cooled motor according to claim 1, characterized in that: The oil circuit operation information includes the number of the oil injection holes of the oil injection ring and the aperture of each of the oil injection holes.

5. The calibration test method for an oil-cooled motor according to claim 4, characterized in that: In step 1, a plurality of first temperature sensor groups are provided on the stator winding of the oil-cooled motor, including: a plurality of temperature sensors provided on the plug-in ends of the stator winding, a plurality of temperature sensors provided on the welding ends of the stator winding, and a plurality of temperature sensors provided on the connecting copper bars of the welding ends of the stator winding; In step 2, the housing is sleeved outside the iron core of the stator and has an interference fit with the iron core; In step 3, the oil injection ring is further installed between the end cover and the iron core.

6. The calibration test method for an oil-cooled motor according to claim 5, characterized in that: The oil passage comprises a plurality of annular oil grooves circumferentially formed on the inner circumferential surface of the housing and a plurality of axial oil grooves axially formed, the annular oil grooves and the axial oil grooves being in communication, an oil inlet and an oil outlet of the oil passage being provided on the housing or the end cover, the oil pump unit delivering the cooling oil to the annular oil grooves and the axial oil grooves through the oil inlet, and the oil pump unit withdrawing the cooling oil from the oil passage through the oil outlet; The axial oil groove and the annular oil groove are used to cooperate with the outer circumferential surface of the iron core. The axial ends of the axial oil groove respectively extend beyond the axial ends of the iron core. The end of the axial oil groove away from the end cover is used to transport the cooling oil to the end of the stator winding away from the end cover; the end of the axial oil groove close to the end cover forms an oil cavity with the housing, the oil spray ring, and the iron core. The oil spray ring is provided with a plurality of oil spray holes distributed along the circumferential direction. One end of the oil spray hole is connected to the oil cavity, and the other end of the oil spray hole faces the end of the stator winding close to the end cover.

7. The calibration test method for an oil-cooled motor according to claim 5, characterized in that: In step 6, the method for judging whether the setting of the oil circuit operation information meets the design requirements based on the temperature distribution information includes: judging whether the temperature difference between the average temperature of the plug end and the average temperature of the welding end is greater than the preset temperature difference based on the temperature distribution information; if it is greater than the preset temperature difference, judging that the setting of the oil circuit operation information does not meet the design requirements; otherwise, judging that the setting of the oil circuit operation information meets the design requirements.

8. The calibration test method for an oil-cooled motor according to claim 5, characterized in that: After determining that the setting of the oil circuit operation information does not meet the design requirements, return to step 4, replace the oil injection ring, adjust the set values ​​of the number of the oil injection holes and the aperture of each oil injection hole in the oil circuit operation information, and perform the next round of simulation and judgment.

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