Control method and system for electrically-driven active heating and vehicle

Abstract

The invention discloses an electric drive active heating control method and system and a vehicle, an active heating power threshold value is determined according to a motor stator accumulated damage coefficient and a motor controller accumulated damage coefficient, actual heating power is determined based on the active heating power threshold value and heating request power, the fatigue life of electric drive parts is considered, and the service life of the electric drive parts is prolonged. While active heating is realized, reduction of reliability of electric drive can be avoided, and safety and reliability of operation of the whole vehicle are guaranteed; meanwhile, after the motor stator temperature impact and the motor controller temperature impact reach corresponding threshold values respectively, the motor stator damage coefficient and the motor controller damage coefficient are calculated, and the motor stator accumulated damage coefficient and the motor controller accumulated damage coefficient are updated and stored, so that the calculation accuracy is ensured; under the condition that the electric driving reliability is not influenced, active heating can be more effectively carried out, and the heating requirement of a battery or a passenger compartment is met.

Description

Technical Field

[0001] The present invention belongs to the field of electric drive systems for electric vehicles, and in particular relates to a control method, system and vehicle for active heating of electric drives. Background Art

[0002] Electric vehicles are mainly powered by electric drive systems ("electric drive" for short), which are mainly composed of motor controllers, motors and reducers. The thermal management system of electric vehicles exchanges heat with the electric drive through coolant, thereby removing the heat during the operation of the electric drive to prevent overheating risks.

[0003] In low temperature environments, the temperature of the electric drive is relatively low, and the electric drive can be used to actively generate heat to provide a heat source for the entire vehicle system. Currently, there are two main methods for active heating of electric drives: pulse heating and stalled rotor heating. Among them, pulse heating is to control the electric drive to generate high-frequency pulse current, which stimulates the internal resistance of the battery to generate heat inside the battery, thereby achieving low-temperature self-heating of the battery; stalled rotor heating is to control the motor to reduce the output efficiency under specific conditions, so that the heat generated by the motor is used to provide auxiliary heating for specific areas of the vehicle (such as the battery and the passenger compartment).

[0004] However, active heating of electric drive will increase the thermal stress of electric drive components, which will increase the reliability risk of electric drive components (such as motor stators and motor controllers). If it is not properly controlled, it will reduce the reliability of electric drive components, cause damage to components, generate power interruptions, and even cause thermal runaway, endangering the life and property of vehicle users. Therefore, it is necessary to control active heating of electric drive based on the fatigue life of electric drive components (reflected in the cumulative damage coefficient) to avoid reducing the reliability of electric drive. Summary of the invention

[0005] The object of the present invention is to provide a control method, system and vehicle for active heating of electric drive, so as to avoid reducing the reliability of the electric drive while achieving active heating, thereby ensuring the reliability of the operation of the entire vehicle.

[0006] When the electric drive is used to drive the entire vehicle, the motor stator and motor controller are subject to temperature shocks. In order to ensure the reliability of the driving conditions throughout the entire life cycle of the electric drive, active heating functions such as stall heating and pulse heating can be performed based on the surplus capacity evaluated based on the entire life cycle of the vehicle. Active heating will cause temperature shocks to the motor stator and motor controller, affecting the service life of the electric drive; therefore, active heating control can be performed based on the cumulative damage coefficient of the motor stator and the cumulative damage coefficient of the motor controller (reflecting the fatigue life of the electric drive).

[0007] In a first aspect, the present invention provides a control method for active heating of an electric drive, comprising:

[0008] In response to the active heating function being turned on (i.e., the active heating starts), the stored motor stator cumulative damage coefficient ε d_all and motor controller cumulative damage factor ε k_all , determine the active heating power threshold P z .

[0009] min(P r ,P z ) as the actual heating power P for active heating (i.e., the actual heating power P = min (P r ,P z ), active heating is performed according to the actual heating power P), and the starting temperature T of the motor stator at this time (i.e. when the active heating function is turned on) is recorded ds , Motor controller starting temperature T ks ; Among them, P r represents the heating request power, and min() represents the minimum value function (min(P r ,P z ) means taking P r With P z The minimum value in .

[0010] In response to the active heating function being turned off (i.e., the active heating is ended), the active heating is stopped, and the motor stator termination temperature T at this time (i.e., when the active heating function is turned off) is recorded. de and the motor controller termination temperature T ke .

[0011] Using the formula: ΔT d =T de -T ds , ΔT k =T ke -T ks , calculate the motor stator temperature shock ΔT during the active heating process d and motor controller temperature shock ΔT k .

[0012] If ΔT d ≥T1, first use the formula: Calculate the stator damage coefficient ε of the motor during the active heating process d , and then let the motor stator cumulative damage coefficient ε d_all Increase ε d , and store (even if ε d_all =ε d_all +ε d , store the updated motor stator cumulative damage coefficient ε d_all), wherein T1 represents the preset temperature change threshold of the motor stator, C1 represents the material constant of the motor stator, a1 represents the plasticity index of the motor stator, C1 and a1 are known quantities, and the initial value of the motor stator cumulative damage coefficient is 0.

[0013] If ΔT k ≥T2, first use the formula: Calculate the motor controller damage coefficient ε during the active heating process k , and then let the motor controller accumulate damage coefficient ε k_all Increase ε k , and store (even if ε k_all =ε k_all +ε k , store the updated motor controller cumulative damage coefficient ε k_all ), wherein T2 represents the preset temperature change threshold of the motor controller, C2 represents the material constant of the motor controller, a2 represents the plasticity index of the motor controller, C2 and a2 are known quantities, and the initial value of the cumulative damage coefficient of the motor controller is 0.

[0014] Preferably, the active heating function includes a pulse heating function and a stalled-rotor heating function.

[0015] When the pulse heating function is turned on, the stored motor stator cumulative damage coefficient ε d_all and motor controller cumulative damage factor ε k_all , determine the active heating power threshold P z The method is:

[0016] According to the motor stator cumulative damage coefficient ε d_all Query the preset correspondence table between the motor stator cumulative damage coefficient and the first pulse heating power to obtain the motor stator cumulative damage coefficient ε d_all The corresponding first pulse heating power P 11 .

[0017] According to the motor controller cumulative damage coefficient ε k_all Query the preset correspondence table between the motor controller cumulative damage coefficient and the second pulse heating power to obtain the motor controller cumulative damage coefficient ε k_all The corresponding second pulse heating power P 12 .

[0018] Using the formula: P z =min(P 11 ,P 12 ), calculate the active heating power threshold P z , that is, the first pulse heating power P 11 With the second pulse heating power P12 The minimum value among them is taken as the active heating power threshold P z .

[0019] Preferably, when the stall heating function is turned on, the motor stator cumulative damage coefficient ε is stored. d_all and motor controller cumulative damage factor ε k_all , determine the active heating power threshold P z The method is:

[0020] According to the motor stator cumulative damage coefficient ε d_all Query the preset correspondence table between the motor stator cumulative damage coefficient and the first stall heating power to obtain the motor stator cumulative damage coefficient ε d_all The corresponding first stall heating power P 21 .

[0021] According to the motor controller cumulative damage coefficient ε k_all Query the preset correspondence table between the motor controller cumulative damage coefficient and the second stall heating power to obtain the motor controller cumulative damage coefficient ε k_all The corresponding second stall heating power P 22 .

[0022] Using the formula: P z =min(P 21 ,P 22 ), calculate the active heating power threshold P z , that is, the first stall heating power P 21 With the second stall heating power P 22 The minimum value among them is taken as the active heating power threshold P z .

[0023] Preferably, in the correspondence table between the cumulative damage coefficient of the motor stator and the first pulse heating power, the larger the cumulative damage coefficient of the motor stator, the smaller the first pulse heating power. Preferably, in the correspondence table between the cumulative damage coefficient of the motor controller and the second pulse heating power, the larger the cumulative damage coefficient of the motor controller, the smaller the second pulse heating power. Preferably, in the correspondence table between the cumulative damage coefficient of the motor stator and the first blocked rotor heating power, the larger the cumulative damage coefficient of the motor stator, the smaller the first blocked rotor heating power. Preferably, in the correspondence table between the cumulative damage coefficient of the motor controller and the second blocked rotor heating power, the larger the cumulative damage coefficient of the motor controller, the smaller the second blocked rotor heating power.

[0024] Preferably, in the correspondence table between the motor stator cumulative damage coefficient and the first pulse heating power, when the motor stator cumulative damage coefficient is greater than or equal to y d*d1, the first pulse heating power is equal to 0. When the motor stator cumulative damage coefficient reaches y d *d1, the pulse heating function is turned off to ensure the reliability of the vehicle operation. In the correspondence table between the motor controller cumulative damage coefficient and the second pulse heating power, when the motor controller cumulative damage coefficient is greater than or equal to y k *k1, the second pulse heating power is equal to 0. When the motor controller cumulative damage coefficient reaches y k *k1, the pulse heating function is turned off to ensure the reliability of the vehicle operation. In the correspondence table between the motor stator cumulative damage coefficient and the first stall heating power, when the motor stator cumulative damage coefficient is greater than or equal to y d *d2, the first stall heating power is equal to 0. When the motor stator cumulative damage coefficient reaches y d *d2, the stall heating function is turned off to ensure the reliability of the vehicle operation. In the correspondence table between the motor controller cumulative damage coefficient and the second stall heating power, when the motor controller cumulative damage coefficient is greater than or equal to y k *k2, the second stall heating power is equal to 0. When the motor controller cumulative damage coefficient reaches y k *k2, the stall heating function is turned off to ensure the reliability of the vehicle operation. d Represents the preset motor stator cumulative damage coefficient threshold, y k represents the preset motor controller cumulative damage coefficient threshold, d1 and d2 represent the cumulative damage coefficient threshold allocation weights of the motor stator during pulse heating and locked-rotor heating, k1 and k2 represent the cumulative damage coefficient threshold allocation weights of the motor controller during pulse heating and locked-rotor heating, d1+d2=1, k1+k2=1. d1, d2, k1, k2 are known quantities.

[0025] Preferably, when the pulse heating function is turned on, if condition 1a or condition 1b is met, the vehicle computer is requested to display the motor stator cumulative damage coefficient ε d_all 、Motor controller cumulative damage coefficient ε k_all and "Limit Pulse Heating" prompt (at this time, the active heating power threshold P z = 0, no pulse heating will be performed), and the motor stator cumulative damage coefficient ε d_all 、Motor controller cumulative damage coefficient ε k_all The "Limit Pulse Heating" prompt is sent to the cloud for background monitoring, and can also be viewed by users through the mobile phone APP. Among them, condition 1a is: the motor stator cumulative damage coefficient ε d_all Greater than or equal to y d *d1; Condition 1b: Motor controller cumulative damage coefficient ε k_all Greater than or equal to y k*k1.

[0026] Preferably, when the stall heating function is turned on, if condition 2a or condition 2b is met, the vehicle computer is requested to display the motor stator cumulative damage coefficient ε d_all 、Motor controller cumulative damage coefficient ε k_all and "Limit stall heating" prompt (at this time, the active heating power threshold P z = 0, no stall heating will be performed), and the motor stator cumulative damage coefficient ε d_all 、Motor controller cumulative damage coefficient ε k_all The "limit stall heating" prompt is sent to the cloud for background monitoring, and can also be viewed by users through the mobile phone APP. Among them, condition 2a is: the motor stator cumulative damage coefficient ε d_all Greater than or equal to y d *d2; Condition 2b: Motor controller cumulative damage coefficient ε k_all Greater than or equal to y k *k2.

[0027] In a second aspect, the present invention provides a control system for active heating of an electric drive, comprising a monitoring controller and a memory, wherein the monitoring controller is programmed to execute the above-mentioned control method for active heating of an electric drive.

[0028] Preferably, the monitoring controller is a vehicle controller or a powertrain controller.

[0029] Preferably, the monitoring controller is a motor controller or a thermal management controller.

[0030] In a third aspect, the present invention provides a vehicle comprising the above-mentioned electric drive active heating control system.

[0031] The present invention has the following effects:

[0032] (1) The active heating power threshold is determined based on the cumulative damage coefficient of the motor stator and the cumulative damage coefficient of the motor controller, and the actual heating power is determined based on the active heating power threshold and the heating request power. The fatigue life of the electric drive components (such as the motor stator and the motor controller) is taken into account, and the reliability of the electric drive is avoided while achieving active heating, thereby ensuring the safety and reliability of the vehicle operation.

[0033] (2) Based on the starting temperature of the motor stator and the ending temperature of the motor stator for active heating, the temperature shock of the motor stator is calculated; based on the starting temperature of the motor controller and the ending temperature of the motor controller for active heating, the temperature shock of the motor controller is calculated; after the temperature shock of the motor stator reaches the preset temperature change threshold of the motor stator, the motor stator damage coefficient is calculated, and the motor stator cumulative damage coefficient is updated and stored; after the temperature shock of the motor controller reaches the preset temperature change threshold of the motor controller, the motor controller damage coefficient is calculated, and the motor controller cumulative damage coefficient is updated and stored; it ensures the accuracy of the calculation of the motor stator cumulative damage coefficient and the motor controller cumulative damage coefficient, and can more effectively perform active heating without affecting the reliability of the electric drive to meet the heating requirements of the battery or the passenger compartment. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 Flow chart of the control method of active heating of electric drive in an embodiment of the present invention.

[0035] Figure 2 Schematic diagram of the relationship between the electric drive active heating temperature difference (i.e., temperature shock) and fatigue life in an embodiment of the present invention.

[0036] Figure 3 The active heating power threshold P is determined when the pulse heating function is turned on in the embodiment of the present invention. z Flow chart of the method.

[0037] Figure 4 The active heating power threshold P is determined when the stall heating function is turned on in the embodiment of the present invention. z Flow chart of the method. DETAILED DESCRIPTION

[0038] In order to enable a more detailed understanding of the features and technical contents of the embodiments of the present invention, the implementation of the embodiments of the present invention is described in detail below in conjunction with the accompanying drawings. The attached drawings are for reference only and are not intended to limit the embodiments of the present invention.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used herein are only for the purpose of describing the embodiments of the present invention and are not intended to limit the present invention.

[0040] In the following description, reference is made to “some embodiments”, which describe a subset of all possible embodiments, but it will be understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0041] Active heating will cause temperature shock to the motor stator and motor controller, affecting the service life of the electric drive (see Figure 2 ). Therefore, active heating control can be performed based on the motor stator cumulative damage coefficient and the motor controller cumulative damage coefficient (reflecting the fatigue life of the electric drive).

[0042] like Figures 1 to 4 As shown, the control method for active heating of the electric drive in the embodiment of the present invention is executed by the monitoring controller and specifically includes:

[0043] Step 1: Determine whether the pulse heating function is turned on. If yes, proceed to step 2; otherwise, proceed to step 6.

[0044] In some embodiments, if the pulse heating function on flag is 1, it means that the pulse heating function is on.

[0045] Step 2: According to the stored motor stator cumulative damage coefficient ε d_all and motor controller cumulative damage factor ε k_all , determine the active heating power threshold P z , and then execute step 3. Among them, the initial value of the motor stator cumulative damage coefficient is 0, and the initial value of the motor controller cumulative damage coefficient is 0.

[0046] like Figure 3 As shown, in some embodiments, determining the active heating power threshold P z The method is:

[0047] First, according to the motor stator cumulative damage coefficient ε d_all Query the preset motor stator cumulative damage coefficient (0, n d1 , n d2 , ..., y d *d1) and the first pulse heating power (P d0 , P d1 , P d2 , ..., 0) (i.e., Table 1), the first pulse heating power P is obtained 11 .

[0048] Table 1

[0049] Motor stator cumulative damage coefficient 0 <![CDATA[n d1 ]]> <![CDATA[n d2 ]]> ... <![CDATA[y d *d1]]> First pulse heating power <![CDATA[P d0 ]]> <![CDATA[P d1 ]]> <![CDATA[P d2 ]]> ... 0

[0050] Then, according to the motor controller cumulative damage coefficient ε k_all Query the preset motor controller cumulative damage coefficient (0, n k1 , n k2 , ..., y k *k1) and the second pulse heating power (P k0 , P k1 , P k2 , ..., 0) (i.e., Table 2), the second pulse heating power P is obtained12 .

[0051] Table 2

[0052] Motor controller cumulative damage coefficient 0 <![CDATA[n k1 ]]> <![CDATA[n k2 ]]> ... <![CDATA[y k *k1]]> Second pulse heating power <![CDATA[P k0 ]]> <![CDATA[P k1 ]]> <![CDATA[P k2 ]]> ... 0

[0053] Finally, using the formula: P z =min(P 11 ,P 12 ), calculate the active heating power threshold P z , that is, the first pulse heating power P 11 The second pulse heating power P 12 The minimum value of the active heating power threshold P z .

[0054] In some embodiments, in the correspondence table between the motor stator cumulative damage coefficient and the first pulse heating power, the larger the motor stator cumulative damage coefficient, the smaller the first pulse heating power. In the correspondence table between the motor controller cumulative damage coefficient and the second pulse heating power, the larger the motor controller cumulative damage coefficient, the smaller the second pulse heating power.

[0055] In some embodiments, in the correspondence table between the motor stator cumulative damage coefficient and the first pulse heating power, when the motor stator cumulative damage coefficient is greater than or equal to y d *d1, the first pulse heating power is equal to 0 (see Table 1); in the corresponding relationship table between the motor controller cumulative damage coefficient and the second pulse heating power, when the motor controller cumulative damage coefficient is greater than or equal to y k *k1, the second pulse heating power is equal to 0 (see Table 2). d Represents the preset motor stator cumulative damage coefficient threshold, y k represents the preset motor controller cumulative damage coefficient threshold, d1 represents the cumulative damage coefficient threshold allocation weight of the motor stator during pulse heating, and k1 represents the cumulative damage coefficient threshold allocation weight of the motor controller during pulse heating. The preset motor stator cumulative damage coefficient threshold y in the present invention d Based on the hardware reliability and safety, the motor stator can withstand the damage coefficient under the maximum temperature shock; the preset motor controller cumulative damage coefficient threshold y k Based on the hardware reliability and safety, the motor controller can withstand the damage coefficient under the maximum temperature shock. The motor stator cumulative damage coefficient exceeds y d , the motor controller cumulative damage coefficient exceeds y k , the reliability of the electric drive cannot be guaranteed and unexpected failures may occur.

[0056] In some embodiments, if ε d_all ≥yd *d1, or ε k_all ≥y k *k1, active heating power threshold P at this time z = 0, pulse heating will not be performed, and the monitoring controller will request the vehicle computer to display ε d_all , ε k_all and "Limit Pulse Heating" prompt, and set ε d_all , ε k_all The “limit pulse heating” prompt is sent to the cloud to ensure the safety of the electric drive and the vehicle throughout its life cycle.

[0057] Step 3: min(P r ,P z ) as the actual heating power P for pulse heating, and record the motor stator starting temperature T at this time ds , Motor controller starting temperature T ks , and then proceed to step 4. Among them, P r represents the heating request power (sent by the vehicle thermal management), and min() represents the minimum value function, i.e. min(P r ,P z ) means taking P r With P z The minimum value in .

[0058] Step 4: Determine whether the pulse heating function is turned off. If so, proceed to step 5, otherwise continue to step 4.

[0059] Step 5: Stop pulse heating and record the motor stator end temperature T at this time. de and the motor controller termination temperature T ke , and then proceed to step eleven.

[0060] Step 6: Determine whether the stall heating function is turned on. If so, proceed to step 7, otherwise end.

[0061] In some embodiments, if the stall heating function on flag is 1, it indicates that the stall heating function is on.

[0062] Step 7: According to the stored motor stator cumulative damage coefficient ε d_all and motor controller cumulative damage factor ε k_all , determine the active heating power threshold P z , and then execute step 8. Among them, the initial value of the motor stator cumulative damage coefficient is 0, and the initial value of the motor controller cumulative damage coefficient is 0.

[0063] like Figure 4 As shown, in some embodiments, determining the active heating power threshold P z The method is:

[0064] First, according to the motor stator cumulative damage coefficient ε d_all Query the preset motor stator cumulative damage coefficient (0, n d1 , n d2 , ..., y d *d2) and the first stall heating power (P 0d , P 1d , P 2d , ..., 0) (i.e., Table 3), the first stall heating power P is obtained 21 .

[0065] Table 3

[0066] Motor stator cumulative damage coefficient 0 <![CDATA[n d1 ]]> <![CDATA[n d2 ]]> ... <h2 style=";text-align:left;direction:ltr"><![CDATA[y <h2 style=";text-align:left;direction:ltr"> d <h2 style=";text-align:left;direction:ltr"> *d2]]><h2 style=";text-align:left;direction:ltr"> First stall heating power <![CDATA[P 0d ]]> <![CDATA[P 1d ]]> <![CDATA[P 2d ]]> ... 0

[0067] Then, according to the motor controller cumulative damage coefficient ε k_all Query the preset motor controller cumulative damage coefficient (0, n k1 , n k2 , ..., y k *k2) and the second stall heating power (P 0k , P 1k , P 2k , ..., 0) (i.e., Table 4), the second stall heating power P is obtained 22 .

[0068] Table 4

[0069] Motor controller cumulative damage coefficient 0 <![CDATA[n k1 ]]> <![CDATA[n k2 ]]> ... <![CDATA[y k *k2]]> Second stall heating power <![CDATA[P 0k ]]> <![CDATA[P 1k ]]> <![CDATA[P 2k ]]> ... 0

[0070] Finally, using the formula: P z =min(P 21 ,P 22 ), calculate the active heating power threshold P z , that is, the first stall heating power P 21 The second stall heating power P 22 The minimum value of the active heating power threshold P z .

[0071] In some embodiments, in the correspondence table between the cumulative damage coefficient of the motor stator and the first stalled rotor heating power, the larger the cumulative damage coefficient of the motor stator, the smaller the first stalled rotor heating power; in the correspondence table between the cumulative damage coefficient of the motor controller and the second stalled rotor heating power, the larger the cumulative damage coefficient of the motor controller, the smaller the second stalled rotor heating power.

[0072] In some embodiments, in the correspondence table between the motor stator cumulative damage coefficient and the first stall heating power, when the motor stator cumulative damage coefficient is greater than or equal to y d*d2, the first stall heating power is equal to 0 (see Table 3); in the corresponding relationship table between the motor controller cumulative damage coefficient and the second stall heating power, when the motor controller cumulative damage coefficient is greater than or equal to y k *k2, the second stall heating power is equal to 0 (see Table 4). Among them, d2 represents the cumulative damage coefficient threshold allocation weight of the motor stator during stall heating, k2 represents the cumulative damage coefficient threshold allocation weight of the motor controller during stall heating, d1+d2=1, k1+k2=1, d1, d2, k1, k2 are all known quantities, which are allocated based on the strategy of the whole vehicle.

[0073] In some embodiments, if ε d_all ≥y d *d2, or ε k_all ≥y k *k2, active heating power threshold P at this time z = 0, no stall heating will be performed, and the monitoring controller will request the vehicle computer to display ε d_all , ε k_all and "Limit stall heating" prompt, and set ε d_all , ε k_all The “limit stall heating” prompt is sent to the cloud to ensure the safety of the electric drive and the vehicle throughout its life cycle.

[0074] Step 8: min(P r ,P z ) as the actual heating power P for stall heating, and record the starting temperature T of the motor stator at this time ds , Motor controller starting temperature T ks , and then proceed to step nine.

[0075] Step nine, determine whether the stall heating function is turned off, if so, proceed to step ten, otherwise continue to step nine.

[0076] Step 10: Stop the stall heating and record the motor stator end temperature T at this time. de and the motor controller termination temperature T ke , and then proceed to step eleven.

[0077] Step 11: Use the formula: ΔT d =T de -T ds , ΔT k =T ke -T ks , calculate the motor stator temperature shock ΔT during the active heating (i.e. pulse heating or stall heating) d and motor controller temperature shock ΔT k , and then proceed to step 12.

[0078] Step 12: Determine whether ΔT d ≥T1, if yes, execute step 13, otherwise execute step 15. Wherein, T1 represents the preset motor stator temperature change threshold.

[0079] Step 13: Use the formula: Calculate the motor stator damage coefficient ε during the active heating process (i.e. pulse heating or stall heating) d , and then execute step 14. Wherein, C1 represents the material constant of the motor stator, a1 represents the plasticity index of the motor stator, and both C1 and a1 are known quantities.

[0080] Step 14: Make the motor stator cumulative damage coefficient ε d_all Increase ε d , and store (even if ε d_all =ε d_all +ε d , store the updated motor stator cumulative damage coefficient ε d_all ), and then proceed to step 15.

[0081] Step 15: Determine whether ΔT k ≥T2, if yes, execute step 16, otherwise end. Wherein, T2 represents the preset motor controller temperature change threshold.

[0082] Step 16: Use the formula: The motor controller damage coefficient ε during the active heating process (i.e. pulse heating or stall heating) is calculated k , and then execute step 17. Wherein, C2 represents the material constant of the motor controller, a2 represents the plasticity index of the motor controller, and both C2 and a2 are known quantities.

[0083] Step 17: Make the motor controller cumulative damage coefficient ε k_all Increase ε k , and store (even if ε k_all =ε k_all +ε k , store the updated motor stator cumulative damage coefficient ε k_all ) and then end.

[0084] An embodiment of the present invention further provides a control system for active heating of an electric drive, which includes a monitoring controller and a memory, wherein the monitoring controller is programmed to execute the control method for active heating of an electric drive.

[0085] In some embodiments, the monitoring controller is a vehicle controller, a powertrain controller, a motor controller, or a thermal management controller.

[0086] An embodiment of the present invention further provides a vehicle, which includes the above-mentioned electric drive active heating control system.

[0087] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A control method for active heating of electric drive, characterized in that: include: In response to the active heating function being turned on, according to the stored motor stator cumulative damage coefficient ε d_all and motor controller cumulative damage factor ε k_all , determine the active heating power threshold P z ; min(P r ,P z ) as the actual heating power P for active heating, and record the starting temperature T of the motor stator at this time ds , Motor controller starting temperature T ks ; Among them, P r Indicates the heating request power, min() indicates the minimum value function; In response to the active heating function being turned off, active heating is stopped, and the motor stator termination temperature T at this time is recorded. de and the motor controller termination temperature T ke ; Using the formula: ΔT d =T de -T ds , ΔT k =T ke -T ks , calculate the motor stator temperature shock ΔT during the active heating process d and motor controller temperature shock ΔT k ; If ΔT d ≥T1, first use the formula: Calculate the motor stator damage coefficient ε during the active heating process d , and then let the motor stator cumulative damage coefficient ε d_all Increase ε d , and store; wherein T1 represents a preset motor stator temperature change threshold, C1 represents a material constant of the motor stator, a1 represents a plasticity index of the motor stator, and the initial value of the motor stator cumulative damage coefficient is 0; If ΔT k ≥T2, first use the formula: Calculate the motor controller damage coefficient ε during the active heating process k , and then let the motor controller accumulate damage coefficient ε k_all Increase ε k , and store; wherein T2 represents the preset temperature change threshold of the motor controller, C2 represents the material constant of the motor controller, a2 represents the plasticity index of the motor controller, and the initial value of the cumulative damage coefficient of the motor controller is 0.

2. The control method for active heating of electric drive according to claim 1, characterized in that: The active heating function includes a pulse heating function and a stalled-rotor heating function; When the pulse heating function is turned on, the stored motor stator cumulative damage coefficient ε d_all and motor controller cumulative damage factor ε k_all , determine the active heating power threshold P z The method is: According to the motor stator cumulative damage coefficient ε d_all Query the preset correspondence table between the motor stator cumulative damage coefficient and the first pulse heating power to obtain the first pulse heating power P 11 ; According to the motor controller cumulative damage coefficient ε k_all Query the preset correspondence table between the motor controller cumulative damage coefficient and the second pulse heating power to obtain the second pulse heating power P 12 ; Using the formula: P z =min(P 11 ,P 12 ), calculate the active heating power threshold P z .

3. The control method for active heating of electric drive according to claim 2, characterized in that: When the stall heating function is turned on, the stored motor stator cumulative damage coefficient ε d_all and motor controller cumulative damage factor ε k_all , determine the active heating power threshold P z The method is: According to the motor stator cumulative damage coefficient ε d_all Query the preset correspondence table between the motor stator cumulative damage coefficient and the first stall heating power to obtain the first stall heating power P 21 ; According to the motor controller cumulative damage coefficient ε k_all Query the preset correspondence table between the motor controller cumulative damage coefficient and the second stall heating power to obtain the second stall heating power P 22 ; Using the formula: P z =min(P 21 ,P 22 ), calculate the active heating power threshold P z .

4. The control method for active heating of electric drive according to claim 3, characterized in that: In the correspondence table between the motor stator cumulative damage coefficient and the first pulse heating power, the greater the motor stator cumulative damage coefficient, the smaller the first pulse heating power; In the correspondence table between the motor controller cumulative damage coefficient and the second pulse heating power, the greater the motor controller cumulative damage coefficient, the smaller the second pulse heating power; In the correspondence table between the motor stator cumulative damage coefficient and the first locked-rotor heating power, the greater the motor stator cumulative damage coefficient, the smaller the first locked-rotor heating power; In the correspondence table between the motor controller cumulative damage coefficient and the second locked-rotor heating power, the greater the motor controller cumulative damage coefficient is, the smaller the second locked-rotor heating power is.

5. The control method for active heating of electric drive according to claim 3, characterized in that: In the correspondence table between the motor stator cumulative damage coefficient and the first pulse heating power, when the motor stator cumulative damage coefficient is greater than or equal to y d *At d1, the first pulse heating power is equal to 0; In the correspondence table between the motor controller cumulative damage coefficient and the second pulse heating power, when the motor controller cumulative damage coefficient is greater than or equal to y k *When k1, the second pulse heating power is equal to 0; In the correspondence table between the motor stator cumulative damage coefficient and the first stall heating power, when the motor stator cumulative damage coefficient is greater than or equal to y d *At d2, the first locked-rotor heating power is equal to 0; In the correspondence table between the motor controller cumulative damage coefficient and the second stall heating power, when the motor controller cumulative damage coefficient is greater than or equal to y k *k2, the second locked-rotor heating power is equal to 0; Among them, y d Represents the preset motor stator cumulative damage coefficient threshold, y k It represents the preset cumulative damage coefficient threshold of the motor controller, d1 and d2 represent the cumulative damage coefficient threshold allocation weights of the motor stator during pulse heating and locked-rotor heating respectively, k1 and k2 represent the cumulative damage coefficient threshold allocation weights of the motor controller during pulse heating and locked-rotor heating respectively, d1+d2=1, k1+k2=1.

6. The control method for active heating of electric drive according to claim 5, characterized in that: When the pulse heating function is turned on, if condition 1a or condition 1b is met, the vehicle computer is requested to display the motor stator cumulative damage coefficient ε d_all 、Motor controller cumulative damage coefficient ε k_all and "Limit Pulse Heating" prompt, and the motor stator cumulative damage coefficient ε d_all 、Motor controller cumulative damage coefficient ε k_all and "Limit Pulse Heating" prompts are sent to the cloud; among them, condition 1a is: the motor stator cumulative damage coefficient ε d_all Greater than or equal to y d *d1; Condition 1b: Motor controller cumulative damage coefficient ε k_all Greater than or equal to y k *k1; When the stall heating function is turned on, if condition 2a or condition 2b is met, the vehicle computer is requested to display the motor stator cumulative damage coefficient ε d_all 、Motor controller cumulative damage coefficient ε k_all and "Limit stall heating" prompt, and the motor stator cumulative damage coefficient ε d_all 、Motor controller cumulative damage coefficient ε k_all and "limit stall heating" prompts are sent to the cloud; among which, condition 2a is: the motor stator cumulative damage coefficient ε d_all Greater than or equal to y d *d2; Condition 2b: Motor controller cumulative damage coefficient ε k_all Greater than or equal to y k *k2.

7. A control system for active heating of an electric drive, comprising a monitoring controller and a memory, characterized in that: The monitoring controller is programmed to execute the control method for active heating of electric drive according to any one of claims 1 to 6.

8. The control system for active heating of electric drive according to claim 7, characterized in that: The monitoring controller is a vehicle controller or a powertrain controller.

9. The control system for active heating of electric drive according to claim 7, characterized in that: The monitoring controller is a motor controller or a thermal management controller.

10. A vehicle, characterized in that: A control system for active heating of electric drive comprising the control system as claimed in any one of claims 7 to 9.

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