Partitioned control analysis method for flow velocity of cooling liquid of water-cooled motor

Abstract

The invention discloses a water-cooled motor cooling liquid flow velocity partition control analysis method, which relates to the technical field of cooling, and comprises the following steps: in a motor design stage, verifying whether a whole vehicle driving condition is met or not according to performance, temperature rise and flow resistance simulation; in the test bottoming stage, partitioning is carried out according to the loss map under the motor pole electric control full working condition, the CLTC working condition points of the whole vehicle are fitted with the loss map, the loss values of two sub-components in the overlapping area are checked, areas capable of surrounding the CLTC working condition operation points are selected respectively, and the flow speed of cooling liquid is set to be aL / min in the areas; in the on-board verification stage, a VCU, a cooling system and an MCU are needed to carry out software calibration and joint debugging, whether an electric-driven derating / shutdown over-temperature fault can be triggered or not is verified during on-board driving, and if not, it is indicated that a cooling liquid flow distribution area is reasonable; the flow of the cooling liquid in different areas is adjusted by adjusting the flow of the cooling liquid in different areas, the heat dissipation power of the cooling water pump is reduced under the condition that the heat dissipation requirement of the whole vehicle driving working condition is met, and the whole vehicle endurance mileage is increased.

Description

Technical Field

[0001] The invention relates to the field of cooling technology, and in particular to a method for analyzing flow rate zoning control of coolant in a water-cooled motor. Background Art

[0002] In recent years, new energy vehicles have developed rapidly, and the sales of electric-drive vehicles in the market have continued to increase. Most domestic OEMs have carried out the research and development of three-in-one electric drive assemblies. During the working process, high-power motors will generate a lot of heat, causing the temperature inside the motor to rise sharply, thereby causing the demagnetization of the magnetic steel, the decline in efficiency, and the failure of the winding insulation layer and the bearing. Risks such as failure, so the heat dissipation design of high-power motors is a very important link. At present, the cooling form of motors on the market mostly adopts water cooling, and oil cooling has not been fully applied due to cost, technology and other factors. Therefore, the cooling capacity design of a water-cooled motor will directly affect the output of performance. Especially in the early design process, although it can be verified by simulation whether the motor performance indicators can be achieved, it lacks the correlation with the vehicle's operating conditions. Moreover, according to industry experience, the coolant flow rate requirement of a general water-cooled motor is 8-12L / min. If different coolant flow rate controls can be adopted for different motor operating areas, the driving economy of the vehicle can be effectively improved and the endurance performance can be further improved. Therefore, water-cooled motor coolant flow rate zoning control technology is urgently needed. Summary of the invention

[0003] In view of the problems existing in the prior art, the present invention conceives a water-cooled motor coolant flow rate zoning control analysis method, which adjusts the coolant flow rate in different areas according to the loss distribution of the motor and electronic control under the full speed range, thereby reducing the heat dissipation power of the cooling water pump and improving the vehicle's cruising range while meeting the heat dissipation requirements of the vehicle's driving conditions.

[0004] The technical solution adopted to realize the present invention is: a water-cooled motor coolant flow rate zoning control analysis method, based on the loss MAP distribution of the motor and the electric control under all working conditions to control the coolant flow rate, characterized in that it includes the following steps:

[0005] 1) During the electric drive design phase, the performance of the vehicle and the electric drive should correspond to:

[0006] The corresponding relationship between the vehicle speed and the motor speed is established through the speed ratio of the reducer and the rolling radius of the tire, as shown in formula (1):

[0007]

[0008] Using the transmission efficiency of the reducer, the corresponding relationship between the wheel end torque and the motor torque is established, as shown in formula (2):

[0009]

[0010] The relationship between vehicle traction and required power is used to calculate the power requirement of the vehicle under uniform speed driving conditions, as shown in formula (3):

[0011]

[0012] Calculate the continuous power target required by the motor at the highest vehicle speed, as shown in formula (4):

[0013] ∑F=F r +F w +F g +F j (4)

[0014] The rolling resistance of the vehicle is calculated based on the rolling friction coefficient and the vehicle curb weight, as shown in formula (5):

[0015] F r =M·g·f r ·cosα (5)

[0016] The air resistance of the vehicle is calculated based on the vehicle speed, air density, and windward area, as shown in formula (6):

[0017]

[0018] The climbing resistance is calculated according to the vehicle curb weight and climbing angle, as shown in formula (7):

[0019] F g =M·g·sinα (7)

[0020] The acceleration resistance of the whole vehicle is calculated according to the rotation mass conversion coefficient and acceleration, as shown in formula (8). The relationship between the motor external characteristics and the vehicle 100 km / h acceleration time is established, and the motor external characteristics inflection point speed is preliminarily calculated according to the vehicle 100 km / h acceleration time requirement. Based on this, the motor peak torque continuous interval is required, as shown in formulas (9), (10), and (11).

[0021]

[0022] T=T1+T2 (9)

[0023]

[0024] Where: v is the vehicle speed, N is the motor speed, r is the tire rolling radius, i g is the transmission ratio of the transmission, i0 is the main reduction ratio; F t is the vehicle traction, T t is the wheel end output torque, η t is the transmission efficiency of the electric drive reducer, Ttq is the output torque of the motor end, ∑F is the sliding resistance of the vehicle, P f is the vehicle driving power, F r is the rolling resistance, F w is the air resistance, F g is the climbing resistance, F j is the acceleration resistance, M is the vehicle equipment mass, g is the gravity acceleration, f r is the rolling friction coefficient, α is the vehicle climbing angle, ρ is the air density, A f is the frontal windward area of ​​the vehicle, C D is the air resistance coefficient, δ is the vehicle rotation mass conversion coefficient, T is the acceleration time of the vehicle per 100 kilometers, T1 is the acceleration time of the motor constant torque interval, T2 is the acceleration time of the motor constant power interval, N1 is the turning point speed, and N2 is the speed corresponding to a vehicle speed of 100 km / h;

[0025] 2) Build electromagnetic, thermal, and flow resistance simulation models of the motor design. In the early design stage, simulate the performance and temperature rise of the motor to ensure that the temperature rise of the motor can meet the parameter target in step 1) and meet the driving condition requirements of the vehicle;

[0026] 3) In the test verification stage, firstly, according to the efficiency test of the electric drive, the loss values ​​of the motor and the electronic control under all working conditions are calculated respectively, and the loss MAP diagram is drawn. Under the electric drive state, the flow path of the electric energy outputting the mechanical energy through the electric drive is analyzed, and the relationship between the loss power and efficiency of the motor and the electronic control is established respectively, as shown in equations (12), (13), (14), (15), and (16);

[0027] P 机损 =P ac -P ad (12)

[0028] P 控损 =P dc -P ac (13)

[0029] η 机 =P ad / P ac (14)

[0030] η 控 =P ac / P dc (15)

[0031] η 总 =η 机 ×η 控 (16)

[0032] When the electric drive is in driving state, where: P机损 , P 控损 are the loss values ​​generated by a single motor and a single electronic control respectively; P dc , P ac , P ad are the DC power, AC power and mechanical power on the electric drive transmission path respectively; η 机 , η 控 , η 总 They are the efficiency of the motor and electronic control, that is, the assembly;

[0033] In the electric drive feeding state, the flow path of mechanical energy outputting electric energy through the electric drive is analyzed, and the relationship between the power loss and efficiency of the motor and the electronic control is established respectively, as shown in equations (17), (18), (19), (20), and (21);

[0034] P 机损' =P ad' -P ac' (17)

[0035] P 控损' =P ac' -P dc' (18)

[0036] η 机' =P ac' / P ad' (19)

[0037] η 控' =P dc' / P ac' (20)

[0038] η 总' =η 机' ×η 控' (twenty one)

[0039] When the electric drive is in the feeding state, the formula is: P 机损' , P 控损' are the loss values ​​generated by a single motor and a single electronic control respectively; P dc' , P ac' , P ad' are the DC power, AC power and mechanical power on the electric drive transmission path respectively; η 机' , η 控' , η 总' They are the efficiency of the motor and electronic control, that is, the assembly;

[0040] Fit the vehicle's CLTC operating points with the loss MAP, and analyze the loss values ​​of the single motor and point electronic control in the overlapping area;

[0041] 4) During the actual vehicle verification stage, the cooling flow partition control logic proposed in step 3) is used for on-vehicle verification, and the test is performed according to the vehicle driving conditions. If the motor does not experience shutdown or derating failure throughout the entire process, the partition flow designed in steps 2), 3), and 4) can meet the heat dissipation requirements of the electric drive; if a shutdown or derating failure occurs, return to step 3) to increase the coolant flow in the selected area appropriately, and calibrate the thermal simulation model in step 2), and perform simulation verification with the newly set flow. If the simulation verifies that the stator winding temperature will not overheat, modify the software logic on the vehicle, adjust the coolant flow requirement, and re-verify the vehicle.

[0042] Further, in step 2), when the motor winding temperature is less than 150° C., the coolant flow rate in the thermal simulation model needs to be ≤8 L / min, and the minimum coolant flow requirement is tested under different operating output conditions.

[0043] Further, in step 3), combined with the simulation in step 2), the full-operating-condition MAP is preliminarily divided into two regions. In the first region, the speed range is: 0 to 12000 rpm, and the torque range is: -100 Nm to 100 Nm. The second region is the remaining part.

[0044] Furthermore, the torque in the selected first area must satisfy ≤ continuous power, and the operating conditions in the selected area must also satisfy output ≥ 30min during actual vehicle driving.

[0045] Further, according to the simulation results in step 2), the cooling liquid flow rate of the motor and the electronic control in the selected first area is set to aL / min, and the flow rate is set to 8L / min under the working condition of the second area.

[0046] The beneficial technical effects of the water-cooled motor coolant flow rate zoning control analysis method of the present invention are embodied in:

[0047] A method for zoning control and analysis of coolant flow rate of water-cooled motors. In the motor design stage, the performance, temperature rise and flow resistance simulation are used to verify whether the driving conditions of the whole vehicle are met. In the test investigation stage, the loss map of the motor pole electronic control under all working conditions is used to partition the motor pole electronic control, and the CLTC working point of the whole vehicle is fitted with it to check the loss values ​​of the two sub-components in the overlapping area, and the areas that can surround the CLTC working point are selected respectively, and the coolant flow rate is set to aL / min in this area. In the vehicle verification stage, the VCU, cooling system and MCU are required to perform software calibration and joint debugging, and the on-vehicle driving verification will trigger the derating / shutdown overtemperature fault of the electric drive. If it is not triggered, it means that the coolant flow distribution area is reasonable. This ensures that lower cooling power is consumed under operating conditions with low motor electronic control losses, thereby improving the vehicle's cruising range performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 This is the motor thermal simulation model diagram;

[0049] Figure 2 It is the model diagram of the motor and electronic control cooling system;

[0050] Figure 3 This is a schematic diagram of the single motor full-operating condition loss MAP;

[0051] Figure 4 This is the MAP diagram of the full-operating loss of the motor + electronic control;

[0052] Figure 5 This is a schematic diagram of the single electronic control full-operating condition loss MAP;

[0053] Figure 6 It is a schematic diagram of motor cooling interaction;

[0054] Figure 7 It is a schematic diagram of the overall efficiency MAP. DETAILED DESCRIPTION

[0055] The following is combined with Figures 1 to 7 The specific implementation manner will further describe the present invention in detail. To make the purpose, technical scheme and advantages of the implementation manner clearer, the technical scheme in the implementation manner will be clearly and completely described in combination with the embodiments of the present invention. The specific implementation manner described here is only used to explain the present invention and is not used to limit the scope of the present invention.

[0056] A method for analyzing the zoning control of the coolant flow rate of a water-cooled motor is provided. The method controls the coolant flow rate of the motor and the electric control in different zones based on the loss MAP distribution under all working conditions of the motor and the electric control. The method comprises the following steps:

[0057] 1) During the electric drive design phase, the performance of the vehicle and the electric drive should correspond to:

[0058] The corresponding relationship between the vehicle speed and the motor speed is established through the speed ratio of the reducer and the rolling radius of the tire, as shown in formula (1):

[0059]

[0060] Using the transmission efficiency of the reducer, the corresponding relationship between the wheel end torque and the motor torque is established, as shown in formula (2):

[0061]

[0062] The relationship between vehicle traction and required power is used to calculate the power requirement of the vehicle under uniform speed driving conditions, as shown in formula (3):

[0063]

[0064] Calculate the continuous power target required by the motor at the highest vehicle speed, as shown in formula (4):

[0065] ∑F=F r +F w +F g +F j (4)

[0066] The rolling resistance of the vehicle is calculated based on the rolling friction coefficient and the vehicle curb weight, as shown in formula (5):

[0067] F r =M·g·f r ·cosα (5)

[0068] The air resistance of the vehicle is calculated based on the vehicle speed, air density, and windward area, as shown in formula (6):

[0069]

[0070] The climbing resistance is calculated according to the vehicle curb weight and climbing angle, as shown in formula (7):

[0071] F g =M·g·sinα (7)

[0072] The acceleration resistance of the whole vehicle is calculated according to the rotation mass conversion coefficient and acceleration, as shown in formula (8). The relationship between the motor external characteristics and the vehicle 100 km / h acceleration time is established, and the motor external characteristics inflection point speed is preliminarily calculated according to the vehicle 100 km / h acceleration time requirement. Based on this, the motor peak torque continuous interval is required, as shown in formulas (9), (10), and (11).

[0073]

[0074] T=T1+T2 (9)

[0075]

[0076] Where: v is the vehicle speed, N is the motor speed, r is the tire rolling radius, i g is the transmission ratio of the transmission, i0 is the main reduction ratio; F t is the vehicle traction, T t is the wheel end output torque, η t is the transmission efficiency of the electric drive reducer, T tq is the output torque of the motor end, ∑F is the sliding resistance of the vehicle, P f is the vehicle driving power, F r is the rolling resistance, F w is the air resistance, F g is the climbing resistance, F jis the acceleration resistance, M is the vehicle equipment mass, g is the gravity acceleration, f r is the rolling friction coefficient, α is the vehicle climbing angle, ρ is the air density, A f is the frontal windward area of ​​the vehicle, C D is the air resistance coefficient, δ is the vehicle rotation mass conversion coefficient, T is the acceleration time of the vehicle per 100 kilometers, T1 is the acceleration time of the motor constant torque interval, T2 is the acceleration time of the motor constant power interval, N1 is the turning point speed, and N2 is the speed corresponding to a vehicle speed of 100 km / h;

[0077] 2) As attached Figure 1 , 2 As shown in the figure, the electromagnetic, thermal and flow resistance simulation models of the motor design are built. In the early design stage, the performance and temperature rise of the motor are simulated to ensure that the temperature rise of the motor can meet the parameter target in step 1) and the driving condition requirements of the whole vehicle. When the motor winding temperature is less than 150°C, the coolant flow rate in the thermal simulation model needs to be ≤8L / min. The minimum requirements for the coolant flow rate are tested under different operating output conditions, which provides a simulation basis for the partitioning of the subsequent electric drive loss MAP measured data, as shown in Table 1.

[0078] Table 1

[0079]

[0080] 3) In the test verification stage, firstly, according to the efficiency test of the electric drive, the loss values ​​of the motor and the electronic control under all working conditions are calculated, and the loss MAP diagram is drawn, as shown in the attached figure. Figure 3 , 4 , 5 and 7, under the electric drive state, the flow path of the electric energy outputting the mechanical energy through the electric drive is analyzed, and the relationship between the power loss and efficiency of the motor and the electronic control is established, as shown in equations (12), (13), (14), (15), and (16);

[0081] P 机损 =P ac -P ad (12)

[0082] P 控损 =P dc -P ac (13)

[0083] η 机 =P ad / P ac (14)

[0084] η 控 =P ac / P dc (15)

[0085] η 总 =η 机 ×η 控 (16)

[0086] When the electric drive is in driving state, where: P 机损 , P 控损 are the loss values ​​generated by a single motor and a single electronic control respectively; P dc , P ac , P ad are the DC power, AC power and mechanical power on the electric drive transmission path respectively; η 机 , η 控 , η 总 They are the efficiency of the motor and electronic control, that is, the assembly;

[0087] In the electric drive feeding state, the flow path of mechanical energy outputting electric energy through the electric drive is analyzed, and the relationship between the power loss and efficiency of the motor and the electronic control is established respectively, as shown in equations (17), (18), (19), (20), and (21);

[0088] P 机损' =P ad' -P ac' (17)

[0089] P 控损' =P ac' -P dc' (18)

[0090] η 机' =P ac' / P ad' (19)

[0091] η 控' =P dc' / P ac' (20)

[0092] η 总' =η 机' ×η 控' (twenty one)

[0093] When the electric drive is in the feeding state, the formula is: P 机损' , P 控损' are the loss values ​​generated by a single motor and a single electronic control respectively; P dc' , P ac' , P ad' are the DC power, AC power and mechanical power on the electric drive transmission path respectively; η 机' , η 控' , η 总' They are the efficiency of the motor and electronic control, that is, the assembly;

[0094] Fit the CLTC operating condition driving points of the whole vehicle with the loss MAP, and analyze the loss values ​​of the single motor and point electronic control in the overlapping area; combine the simulation in step 2) to preliminarily divide the full operating condition MAP into two areas. In the first area, the speed range is: 0~12000rpm, the torque range is: -100Nm~100Nm, and the second area is the remaining part. The torque selected in the first area must meet ≤ continuous power. The operating conditions in the selected area also need to meet the output ≥30min during actual vehicle driving. According to the simulation results in step 2), the coolant flow rate of the motor and electronic control in the selected first area is set to aL / min, and the flow rate is set to 8L / min under the operating conditions of the second area. 4) In the actual vehicle verification stage, the cooling flow partition control logic proposed in step 3) is used for on-board verification, as shown in the attached figure. Figure 6 As shown, the test is carried out according to the driving condition of the whole vehicle. If the motor does not shut down or derate during the whole process, the partition flow designed in steps 2), 3), and 4) can meet the heat dissipation requirements of the electric drive; if a shutdown or derate failure occurs, return to step 3) to increase the coolant flow in the selected area appropriately, and check the thermal simulation model in step 2), and use the newly set flow to perform simulation verification. If the simulation verifies that the stator winding temperature will not overheat, modify the software logic on the vehicle, adjust the coolant flow requirement, and re-enter the vehicle for verification.

[0095] The above is only a preferred embodiment of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for analyzing the flow rate of coolant in a water-cooled motor by zone control, which controls the flow rate of coolant by zones based on the loss MAP distribution of the motor and electronic control under all working conditions, and is characterized by: It includes the following steps: 1) During the electric drive design phase, the performance of the vehicle and the electric drive should correspond to: The corresponding relationship between the vehicle speed and the motor speed is established through the speed ratio of the reducer and the rolling radius of the tire, as shown in formula (1): Using the transmission efficiency of the reducer, the corresponding relationship between the wheel end torque and the motor torque is established, as shown in formula (2): The relationship between vehicle traction and required power is used to calculate the power requirement of the vehicle under uniform speed driving conditions, as shown in formula (3): Calculate the continuous power target required by the motor at the highest vehicle speed, as shown in formula (4): ∑F=F r +F w +F g +F j (4) The rolling resistance of the vehicle is calculated based on the rolling friction coefficient and the vehicle curb weight, as shown in formula (5): F r =M·g·f r ·cosα (5) The air resistance of the vehicle is calculated based on the vehicle speed, air density, and windward area, as shown in formula (6): The climbing resistance is calculated according to the vehicle curb weight and climbing angle, as shown in formula (7): F g =M·g·sinα (7) The acceleration resistance of the whole vehicle is calculated according to the rotation mass conversion coefficient and acceleration, as shown in formula (8). The relationship between the motor external characteristics and the vehicle 100 km / h acceleration time is established, and the motor external characteristics inflection point speed is preliminarily calculated according to the vehicle 100 km / h acceleration time requirement. Based on this, the motor peak torque continuous interval is required, as shown in formulas (9), (10), and (11). T=T1+T2 (9) Where: v is the vehicle speed, N is the motor speed, r is the tire rolling radius, i g is the transmission ratio of the transmission, i0 is the main reduction ratio; F t is the vehicle traction, T t is the wheel end output torque, η t is the transmission efficiency of the electric drive reducer, T tq is the output torque of the motor end, ∑F is the sliding resistance of the vehicle, P f is the vehicle driving power, F r is the rolling resistance, F w is the air resistance, F g is the climbing resistance, F j is the acceleration resistance, M is the vehicle equipment mass, g is the gravity acceleration, f r is the rolling friction coefficient, α is the vehicle climbing angle, ρ is the air density, A f is the frontal windward area of ​​the vehicle, C D is the air resistance coefficient, δ is the vehicle rotation mass conversion coefficient, T is the acceleration time of the vehicle per 100 kilometers, T1 is the acceleration time of the motor constant torque interval, T2 is the acceleration time of the motor constant power interval, N1 is the turning point speed, and N2 is the speed corresponding to a vehicle speed of 100 km / h; 2) Build electromagnetic, thermal, and flow resistance simulation models of the motor design. In the early design stage, simulate the performance and temperature rise of the motor to ensure that the temperature rise of the motor can meet the parameter target in step 1) and meet the driving condition requirements of the vehicle; 3) In the test verification stage, firstly, according to the efficiency test of the electric drive, the loss values ​​of the motor and the electronic control under all working conditions are calculated respectively, and the loss MAP diagram is drawn. Under the electric drive state, the flow path of the electric energy outputting the mechanical energy through the electric drive is analyzed, and the relationship between the loss power and efficiency of the motor and the electronic control is established respectively, as shown in equations (12), (13), (14), (15), and (16); P 机损 =P ac -P ad (12) P 控损 =P dc -P ac (13) η 机 JP ad / P ac (14) η 控 JP ac / P dc (15) or 总 =the 机 ×h 控 (16) When the electric drive is in driving state, where: P 机损 , P 控损 are the loss values ​​generated by a single motor and a single electronic control respectively; P dc , P ac , P ad are the DC power, AC power and mechanical power on the electric drive transmission path respectively; η 机 , η 控 , η 总 They are the efficiency of the motor and electronic control, that is, the assembly; In the electric drive feeding state, the flow path of mechanical energy outputting electric energy through the electric drive is analyzed, and the relationship between the power loss and efficiency of the motor and the electronic control is established respectively, as shown in equations (17), (18), (19), (20), and (21); P 机损' =P ad' -P ac' (17) P 控损' =P ac' -P dc' (18) η 机' JP ac' / P ad' (19) η 控' JP dc' / P ac' (20) or 总' =the 机' ×h 控' (21) When the electric drive is in the feeding state, the formula is: P 机损' , P 控损' are the loss values ​​generated by a single motor and a single electronic control respectively; P dc' , P ac' , P ad' are the DC power, AC power and mechanical power on the electric drive transmission path respectively; η 机' , η 控' , η 总' They are the efficiency of the motor and electronic control, that is, the assembly; Fit the vehicle's CLTC operating points with the loss MAP, and analyze the loss values ​​of the single motor and point electronic control in the overlapping area; 4) During the actual vehicle verification stage, the cooling flow partition control logic proposed in step 3) is used for on-vehicle verification, and the test is performed according to the vehicle driving conditions. If the motor does not experience shutdown or derating failure throughout the entire process, the partition flow designed in steps 2), 3), and 4) can meet the heat dissipation requirements of the electric drive; if a shutdown or derating failure occurs, return to step 3) to increase the coolant flow in the selected area appropriately, and calibrate the thermal simulation model in step 2), and perform simulation verification with the newly set flow. If the simulation verifies that the stator winding temperature will not overheat, modify the software logic on the vehicle, adjust the coolant flow requirement, and re-verify the vehicle.

2. The method for analyzing the flow rate of coolant of a water-cooled motor according to claim 1 is characterized in that: In step 2), when the motor winding temperature is less than 150°C, the coolant flow rate in the thermal simulation model needs to be ≤8L / min, and the minimum coolant flow requirement is tested under different operating output conditions.

3. The method for analyzing the flow rate of coolant of a water-cooled motor according to claim 1 is characterized in that: In step 3), combined with the simulation in step 2), the full-operating-condition MAP is preliminarily divided into two regions. In the first region, the speed range is: 0 to 12000 rpm, the torque range is: -100 Nm to 100 Nm, and the second region is the remaining part.

4. The method for analyzing the flow rate of coolant of a water-cooled motor according to claim 3 is characterized in that: The torque in the selected first area must meet the requirement of ≤ continuous power, and the operating conditions in the selected area must also meet the requirement of output ≥ 30min during actual vehicle driving.

5. The method for analyzing the flow rate of coolant of a water-cooled motor according to claim 3 is characterized in that: According to the simulation results in step 2), the cooling liquid flow rate of the motor and the electronic control in the selected first area is set to aL / min, and the flow rate is set to 8L / min under the working conditions of the second area.

Images