Integrated thermal management system refrigerant flow distribution control method and system

Abstract

The present application relates to the technical field of heat management, and more particularly to a kind of integrated heat management system refrigerant flow distribution control method and system, if receiving cab side refrigeration demand signal, according to cab side target suction gas superheat adjustment cab side first electronic expansion valve step response cab side refrigeration demand;If receiving battery side refrigeration demand signal, first determine whether response battery side refrigeration demand;If response battery side refrigeration demand, according to battery side target suction gas superheat adjustment battery side second electronic expansion valve step response battery side refrigeration demand.The present application can effectively adjust the step of cab side first electronic expansion valve and the step of battery side second electronic expansion valve by setting cab side target suction gas superheat and battery side target suction gas superheat, reasonably distribute refrigerant flow of cab cooling circuit and battery cooling circuit, both can make battery maintain in suitable temperature range, and reach the purpose of priority guaranteeing cab comfort.

Description

Technical Field

[0001] This invention relates to the technical field of thermal management, and more specifically, to an integrated thermal management system and a method and system for controlling refrigerant flow distribution. Background Technology

[0002] With the continuous rise in oil prices, the development of new energy vehicles is accelerating. In the integrated thermal management architecture of new energy vehicles, the cab cooling circuit mostly uses thermostatic expansion valves and shut-off valves, while the battery cooling circuit uses electronic expansion valves. Since thermostatic expansion valves control the valve needle opening by sensing changes in the refrigerant temperature at the evaporator outlet through a temperature sensor to regulate refrigerant flow, manual adjustment of the refrigerant flow in the cab cooling circuit is impossible. In the integrated thermal management system, the cab cooling circuit piping is much longer than the battery cooling circuit, and the refrigerant flow allocated to the battery cooling circuit is always greater than that to the cab cooling circuit, resulting in insufficient refrigerant in the cab cooling circuit and affecting cab comfort. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide an integrated thermal management system refrigerant flow distribution control method and system that can prioritize the comfort of the cab while also ensuring that the battery is within a suitable temperature range.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0005] A method for refrigerant flow distribution control in an integrated thermal management system is provided, comprising the following steps:

[0006] Collect data on the cab interior temperature, average battery temperature, battery coolant inlet temperature, driver-side cooling circuit refrigerant low-pressure side pressure and temperature, and battery-side cooling circuit refrigerant low-pressure side pressure and temperature.

[0007] Set and maintain the target intake superheat T on the cab side. dri_T T1 is the actual intake superheat T on the cab side, calculated based on the low-pressure side pressure and temperature values ​​of the refrigerant in the driver's side cooling circuit. dri ;

[0008] Adjust the target intake superheat T on the battery side according to vehicle operating conditions, average battery temperature, and battery coolant inlet temperature. Batt_T The actual intake superheat T on the battery side is calculated based on the pressure and temperature values ​​of the refrigerant on the low-pressure side of the battery-side cooling circuit. Batt ;

[0009] If a cooling demand signal is received from the cab side, the following steps are taken to respond to the cab side cooling demand: When the actual intake superheat T on the cab side... dri Less than the target intake superheat T on the cab sidedri_T , then reducing the step length of the first electronic expansion valve on the driver's cabin side; when the actual suction superheat value T on the driver's cabin side dri is greater than the target suction superheat T on the driver's cabin side dri_T , then increasing the step length of the first electronic expansion valve on the driver's cabin side;

[0010] if a battery-side cooling demand signal is received, determining whether to respond to the battery-side cooling demand according to the average battery temperature and the indoor temperature of the driver's cabin; if responding to the battery-side cooling demand, responding according to the following steps: when the actual suction superheat T on the battery side Batt is less than the target suction superheat T on the battery side Batt_T , then reducing the step length of the second electronic expansion valve on the battery side; when the actual suction superheat T on the battery side Batt is greater than the target suction superheat T on the battery side Batt_T , then increasing the step length of the second electronic expansion valve on the battery side.

[0011] In the refrigerant flow distribution control method for the integrated thermal management system of the present invention, the refrigerant flow of a driver's cabin cooling circuit and a battery cooling circuit is distributed by setting the target suction superheat on the driver's cabin side and the target suction superheat on the battery side, the target suction superheat on the driver's cabin side is set as a fixed value, and the target suction superheat on the battery side is adjusted according to vehicle working conditions, the average battery temperature and the inlet water temperature of battery coolant, so that the step length of the first electronic expansion valve on the driver's cabin side and the step length of the second electronic expansion valve on the battery side can be effectively adjusted, which not only enables the battery to be maintained within a proper temperature range, but also achieves the purpose of preferentially ensuring the comfort of the driver's cabin.

[0012] Preferably, when the vehicle working condition is a charging working condition, the target suction superheat T on the battery side is set Batt_T as T5, wherein T1<T5. During charging, the temperature of the battery rises rapidly, and it is necessary to increase the refrigerant flow of the battery-side cooling circuit. The target suction superheat on the battery side is greater than the target suction superheat on the driver's cabin side, so that the battery-side cooling circuit can be allocated with refrigerant flow to cool down the battery.

[0013] Preferably, when the vehicle working condition is a driving working condition, both the driver's cabin side and the battery side have cooling demands, and the target suction superheat T on the battery side is determined according to the average battery temperature and the inlet water temperature of battery coolant Batt_T :

[0014] If the average battery temperature T avg is greater than a first set average temperature T a1 , and the inlet water temperature T of battery coolant cool is greater than a first set water temperature T c1 , at this time, the heat dissipation of the battery is too slow and the average temperature of the battery is too high, so it is necessary to increase the refrigerant flow of the battery-side cooling circuit, lower the target suction superheat value on the battery side, and set the target suction superheat T on the battery sideBatt_T Designated as T2;

[0015] If the average battery temperature T avg Greater than the second set average temperature T a2 And the battery coolant inlet water temperature T cool Greater than the second set water temperature T c2 At this point, the battery dissipates heat slowly, and the average battery temperature is high. It is necessary to increase the refrigerant flow rate in the battery-side cooling circuit and lower the target intake superheat value on the battery side. Batt_T Designated as T3;

[0016] If the average battery temperature T avg Less than the third set average temperature T a3 Or the battery coolant inlet water temperature T cool Less than the third set water temperature T c3 At this point, the battery heat dissipation rate is normal, the battery coolant inlet temperature has basically reached the target temperature, and the target intake superheat T on the battery side is within acceptable limits. Batt_T Designated as T4;

[0017] The relationship between the target intake superheat value, the average battery temperature, and the battery coolant inlet temperature is as follows: T1 <T5<T2<T3<T4;T a1 >T a2 >T a3 ;T c1 =T c2 >T c3 .

[0018] By adjusting the target intake superheat on the cab side and the target intake superheat on the battery side, the opening of the first electronic expansion valve on the cab side and the second electronic expansion valve on the battery side can be adjusted, thereby achieving the purpose of distributing the refrigerant flow.

[0019] Preferably, when both battery-side cooling demand and cab-side cooling demand exist simultaneously, the decision to respond to the battery-side cooling demand is based on the cab interior temperature and the average battery temperature:

[0020] If the average battery temperature is less than T a4 The temperature inside the driver's cab is greater than T. c4 The battery-side cooling demand will not be responded to temporarily until the cab interior temperature drops to T. c5 Then, respond to the cooling needs on the battery side;

[0021] If the average battery temperature rises to T a5 Then it will immediately respond to the cooling demand on the battery side;

[0022] Wherein: T a4 <T a5 T c4>T c5 .

[0023] According to the refrigeration demand of the cab side and the refrigeration demand of the battery side, the refrigerant flow is distributed in staggered peaks, which can not only keep the battery within a suitable temperature range, but also achieve the purpose of preferentially ensuring the comfort of the cab.

[0024] Preferably, when it is necessary to respond to the suddenly intervened refrigeration demand on the battery side at a certain moment during the process of responding to the refrigeration demand on the cab side, the refrigeration demand on the battery side is responded step by step, so as to avoid the sudden reduction of the refrigerant flow in the cooling circuit of the cab that affects the comfort of the cab.

[0025] Preferably, responding to the refrigeration demand on the battery side comprises a rotation speed response of a compressor on the battery side, and the specific steps are as follows:

[0026] First, the compressor operates at a rotation speed N1 for t1 seconds;

[0027] then operates at a rotation speed N2 for t2 seconds;

[0028] then operates at a rotation speed N3 for t3 seconds;

[0029] finally, the rotation speed is increased to N4 and keeps operating;

[0030] wherein, N1<N2<N3<N4, and N4 is the required rotation speed of the compressor.

[0031] Preferably, responding to the refrigeration demand on the battery side comprises a step response of a second electronic expansion valve on the battery side, and the specific steps are as follows:

[0032] the initial step of the second electronic expansion valve on the battery side is S1;

[0033] the step is increased by S2 every t4 seconds, and the duration is t5 seconds;

[0034] when the rotation speed of the compressor on the battery side reaches the required rotation speed of the compressor, or when t5>t1+t2+t3, the step of the second electronic expansion valve on the battery side is increased to S3;

[0035] wherein, S1<S2<S3, and S3 is the required step of the second electronic expansion valve on the battery side.

[0036] Preferably, the required rotation speed of the compressor is obtained by querying a Map table according to the difference between the water temperature at a battery coolant inlet and a target water temperature, and the required step of the second electronic expansion valve on the battery side is based on the actual suction superheat T on the battery side Batt and the difference between the target suction superheat T on the battery side Batt_T is calculated.

[0037] Preferably, when the speed of the battery-side compressor reaches the set speed value Nt, the step size of the battery-side second electronic expansion valve is increased; when the step size of the battery-side second electronic expansion valve reaches the set step size St, the speed of the battery-side compressor is increased, so as to avoid the step size of the second electronic expansion valve from increasing to the upper limit and to avoid the compressor from overloading, thus ensuring the safety and continuity of operation.

[0038] The present invention also provides an integrated thermal management system refrigerant flow distribution control system, comprising:

[0039] The data acquisition module is used to collect data on the cab interior temperature, average battery temperature, battery coolant inlet water temperature, driver-side cooling circuit low-pressure side pressure and temperature, and battery-side cooling circuit low-pressure side pressure and temperature.

[0040] Setting module: Used to set and maintain the target intake superheat T on the cab side. dri_T And for adjusting the target intake superheat T on the battery side according to vehicle operating conditions, average battery temperature, and battery coolant inlet temperature. Batt_T ;

[0041] Calculation module: Used to calculate the actual intake superheat T on the cab side based on the low-pressure side pressure and temperature values ​​of the refrigerant in the driver's side cooling circuit. dri And used to calculate the actual intake superheat T on the battery side based on the low-pressure side pressure and temperature values ​​of the refrigerant in the battery-side cooling circuit. Batt ;

[0042] Comparison and Judgment Module: Used to compare the actual intake superheat T on the cab side. dri The target intake superheat T on the cab side dri_T Relative size, used to compare the actual intake superheat T on the battery side. Batt With battery-side target intake superheat T Batt_T The relative size, and whether to respond to the cooling demand on the battery side based on the average battery temperature and the cab interior temperature;

[0043] Control module: Used to receive and respond to the cooling demand signal from the cab side. When the actual intake superheat T on the cab side... dri Less than the target intake superheat T on the cab side dri_T Then reduce the step size of the first electronic expansion valve on the cab side; when the actual intake superheat value T on the cab side... dri Greater than the target intake superheat T on the cab side dri_T Then, the step size of the first electronic expansion valve on the cab side is increased; and it is used to receive and respond to the battery-side cooling demand signal, when the actual intake superheat T on the battery side... Batt Less than the target intake superheat T on the battery side Batt_TThen reduce the step size of the second electronic expansion valve on the battery side; when the actual intake superheat T on the battery side... dri Greater than the target intake superheat T on the battery side Batt_T This increases the step size of the second electronic expansion valve on the battery side.

[0044] The integrated thermal management system refrigerant flow distribution control system of the present invention distributes the refrigerant flow of the cab cooling circuit and the battery cooling circuit by setting the target intake superheat on the cab side and the target intake superheat on the battery side. The target intake superheat on the cab side is set to a certain value, while the target intake superheat on the battery side is adjusted according to the vehicle operating conditions, the average battery temperature, and the battery coolant inlet water temperature. This can effectively adjust the step size of the first electronic expansion valve on the cab side and the step size of the second electronic expansion valve on the battery side, so as to maintain the battery within a suitable temperature range and achieve the goal of prioritizing the comfort of the cab.

[0045] Compared with the prior art, the beneficial effects of the present invention are:

[0046] The integrated thermal management system refrigerant flow distribution control method and system of the present invention sets the target intake superheat on the cab side to a certain value, while the target intake superheat on the battery side is adjusted according to the vehicle operating conditions, the average battery temperature and the battery coolant inlet water temperature, so as to prioritize the cooling demand on the cab side, which can keep the battery within a suitable temperature range and achieve the goal of prioritizing the comfort of the cab.

[0047] The integrated thermal management system refrigerant flow distribution control method and system of the present invention, when there are simultaneous cooling needs on the battery side and cooling needs on the cab side, allocates refrigerant flow in a staggered manner according to the cooling needs on the cab side and the cooling needs on the battery side, so as to maintain the battery within a suitable temperature range and achieve the goal of prioritizing the comfort of the cab.

[0048] The integrated thermal management system refrigerant flow distribution control method and system of the present invention, when responding to the cooling demand of the cab side at a certain moment and needing to respond to the cooling demand of the battery side that suddenly intervenes, responds to the cooling demand of the battery side in a step-by-step manner, so as to avoid the sudden reduction of refrigerant flow in the cab cooling circuit and affect the comfort of the cab. This allows the battery to be maintained within a suitable temperature range, while also prioritizing the comfort of the cab. Attached Figure Description

[0049] Figure 1 The flowchart shows the adjustment process of the first electronic expansion valve on the cab side.

[0050] Figure 2 The flowchart shows the adjustment process of the first electronic expansion valve on the battery side.

[0051] Figure 3A schematic diagram of the process for setting the target intake superheat on the battery side based on the average battery temperature and the battery coolant inlet water temperature;

[0052] Figure 4 A schematic diagram illustrating the execution flow of the compressor speed on the battery side and the opening degree of the second electronic expansion valve on the battery side when battery cooling is suddenly intervened. Detailed Implementation

[0053] The present invention will be further described below with reference to specific embodiments.

[0054] Example 1

[0055] like Figure 1 The first embodiment of the refrigerant flow distribution control method for the integrated thermal management system of the present invention is shown, which includes the following steps:

[0056] Collect data on the cab interior temperature, average battery temperature, battery coolant inlet temperature, driver-side cooling circuit refrigerant low-pressure side pressure and temperature, and battery-side cooling circuit refrigerant low-pressure side pressure and temperature.

[0057] Set and maintain the target intake superheat T on the cab side. dri_T T1 is the actual intake superheat T on the cab side, calculated based on the low-pressure side pressure and temperature values ​​of the refrigerant in the driver's side cooling circuit. dri ; can be achieved by adjusting the actual intake superheat T on the cab side dri The input is fed into the PID control algorithm to obtain the required step size of the first electronic expansion valve on the cab side;

[0058] Adjust the target intake superheat T on the battery side according to vehicle operating conditions, average battery temperature, and battery coolant inlet temperature. Batt_T The actual intake superheat T on the battery side is calculated based on the pressure and temperature values ​​of the refrigerant on the low-pressure side of the battery-side cooling circuit. Batt Among them, the target intake superheat on the battery side specifically refers to the target intake superheat on the chiller side of the battery cooling circuit, which can be determined by adjusting the actual intake superheat T on the battery side. Batt The input is fed into the PID control algorithm to obtain the required step size of the second electronic expansion valve on the battery side.

[0059] If a cooling demand signal is received from the cab side, the following steps are taken to respond to the cab side cooling demand: When the actual intake superheat T on the cab side... dri Less than the target intake superheat T on the cab side dri_T Then reduce the step size of the first electronic expansion valve on the cab side; when the actual intake superheat value T on the cab side... dri Greater than the target intake superheat T on the cab side dri_T Then increase the step size of the first electronic expansion valve on the cab side, such as Figure 1 As shown;

[0060] If a battery-side cooling demand signal is received, determine whether to respond to the battery-side cooling demand based on the average battery temperature and the cab interior temperature; if responding to the battery-side cooling demand, proceed as follows: when the actual intake superheat T on the battery side... Batt Less than the target intake superheat T on the battery side Batt_T Then reduce the step size of the second electronic expansion valve on the battery side; when the actual intake superheat T on the battery side... Batt Greater than the target intake superheat T on the battery side Batt_T Then increase the step size of the second electronic expansion valve on the battery side, such as Figure 2 As shown.

[0061] From the above, for the cab side: the target intake superheat T on the cab side dri_T The smaller the set value, the larger the step size of the first electronic expansion valve in the cab-side cooling circuit, and the more refrigerant flow can be allocated to the cab-side cooling circuit; for the battery side: the target intake superheat T on the battery side Batt_T The smaller the set value, the larger the step size of the second electronic expansion valve in the battery-side cooling circuit, and the more refrigerant flow can be allocated to the battery-side cooling circuit. Therefore, depending on the set target intake superheat T on the cab side... dri_T and battery-side target intake superheat T Batt_T It can allocate the refrigerant flow between the cab-side cooling circuit and the battery-side cooling circuit.

[0062] In this embodiment, the target intake superheat T on the cab side is set. dri_T and battery-side target intake superheat T Batt_T To allocate refrigerant flow. Cab-side target intake superheat T dri_T and battery-side target intake superheat T Batt_T The superheat of the compressor intake needs to be maintained within an appropriate range; excessively high or low temperatures can damage the compressor. The compressor intake superheat can be maintained within a suitable range by adjusting the step size of the first electronic expansion valve on the cab side and the second electronic expansion valve on the battery side. To maintain cab comfort, the target intake superheat on the cab side is set to a fixed value, while the target intake superheat on the battery side is determined based on the average battery temperature and the battery coolant inlet temperature. Therefore, by adjusting the step size of the first electronic expansion valve on the cab side and the second electronic expansion valve on the battery side according to the target intake superheat, the compressor intake superheat can be kept within a suitable range, thereby achieving the purpose of distributing the refrigerant flow in each cooling circuit.

[0063] To prioritize cab comfort, the target intake superheat on the cab side is maintained at T1, and the target intake superheat on the battery side is T... Batt_TThe changes are based on the average battery temperature and the battery coolant inlet temperature, and are implemented as follows:

[0064] When the vehicle is in charging mode, set the target intake superheat T on the battery side. Batt_T For T5, T1 <T5。

[0065] When the vehicle is in driving condition, there is a cooling demand on both the cab side and the battery side. The target intake superheat T on the battery side is determined based on the average battery temperature and the battery coolant inlet temperature. Batt_T :

[0066] (1) If the average battery temperature T avg Greater than the first set average temperature T a1 And the battery coolant inlet water temperature T cool Greater than the first set water temperature T c1 At this point, the battery is dissipating heat too slowly, and the average battery temperature is too high. It is necessary to increase the refrigerant flow rate in the battery-side cooling circuit and lower the target intake superheat value on the battery side. Batt_T Designated as T2;

[0067] (2) If the average battery temperature T avg Greater than the second set average temperature T a2 And the battery coolant inlet water temperature T cool Greater than the second set water temperature T c2 At this point, the battery dissipates heat slowly, and the average battery temperature is high. It is necessary to increase the refrigerant flow rate in the battery-side cooling circuit and lower the target intake superheat value on the battery side. Batt_T Designated as T3;

[0068] (3) If the average battery temperature T avg Less than the third set average temperature T a3 Or the battery coolant inlet water temperature T cool Less than the third set water temperature T c3 At this point, the battery heat dissipation rate is normal, the battery coolant inlet temperature has basically reached the target temperature, and the target intake superheat T on the battery side is within acceptable limits. Batt_T Designated as T4;

[0069] The relationship between the target intake superheat value, the average battery temperature, and the battery coolant inlet temperature is as follows: T1 <T5<T2<T3<T4;T a1 >T a2 >T a3 ;T c1 =T c2 >T c3 .

[0070] The target intake superheat T on the battery side is determined using the steps (1) to (3) above. Batt_T In this case, steps (1), (2), and (3) can be executed in any order, or they can be executed sequentially. For example... Figure 3 As shown, specifically, (1) first determine whether the following condition is met: T avg >T a1 And T cool >T c1 If yes, output the target intake superheat T2 on the battery side; if no, proceed to step (2); (2) First determine whether the following condition is met: T avg >T a2 And T cool >T c2 If yes, output the target intake superheat T3 on the battery side; if no, proceed to step (3); (3) First determine whether the following condition is met: T avg <T a3 And T cool <T c3 If so, then output the target intake superheat T4 on the battery side.

[0071] In summary, this embodiment provides a refrigerant distribution control method for both charging and driving conditions. By adjusting the target intake superheat on the cab side and the target intake superheat on the battery side, the opening of the first electronic expansion valve on the cab side and the second electronic expansion valve on the battery side is adjusted to distribute the refrigerant flow, thereby achieving the goal of maintaining the battery within a suitable temperature range while prioritizing cab comfort.

[0072] Example 2

[0073] This embodiment is the second embodiment of the refrigerant flow distribution control method for the integrated thermal management system of the present invention. This embodiment is similar to the first embodiment, except that there are simultaneous cooling demands on both the battery side and the cab side. If both cooling demands are responded to simultaneously, the cab cooling circuit is longer, and the allocated refrigerant flow is less than that of the battery circuit, requiring a longer time to cool the cab temperature to a comfortable level. To ensure cab comfort, the cab interior temperature needs to be reduced quickly. Therefore, before allocating the refrigerant flow, this embodiment first determines whether to respond to the battery-side cooling demand based on the cab interior temperature and the average battery temperature. The specific determination is as follows:

[0074] If the average battery temperature is less than T a4 The temperature inside the driver's cab is greater than T. c4 The battery-side cooling demand will not be responded to temporarily until the cab interior temperature drops to T. c5 Then, respond to the cooling needs on the battery side;

[0075] If, during this process, the average battery temperature rises to T... a5 Then it will immediately respond to the cooling demand on the battery side;

[0076] Wherein: T a4 <T a5 T c4 >T c5 .

[0077] Based on the cooling needs of the cab and the battery, the refrigerant flow is allocated in a staggered manner, which can keep the battery within a suitable temperature range and also prioritize the comfort of the cab.

[0078] This embodiment is applicable to usage scenarios where both battery-side and cab-side cooling needs exist simultaneously, such as when a car has been exposed to the sun for half a day, resulting in high cab interior temperatures, high average battery temperatures, and high battery coolant inlet temperatures, requiring significant cooling capacity from both the cab cooling circuit and the cab cooling circuit. Of course, the refrigerant distribution and control method of this invention is not limited to this scenario.

[0079] Example 3

[0080] This embodiment is the third embodiment of the refrigerant flow distribution control method for the integrated thermal management system of the present invention. This embodiment is similar to Embodiment 1 or Embodiment 2, except that this embodiment is suitable for refrigerant distribution control in a scenario where, during the response to the cooling demand on the cab side, a sudden intervention in the cooling demand on the battery side is required. At this time, due to the large temperature difference between the battery coolant inlet water temperature and the target water temperature, the required battery-side compressor speed is high. If the cooling demand on the battery is directly responded to, the refrigerant flow rate distributed will be less than that on the battery cooling circuit due to the longer cab cooling circuit piping. Directly responding to the battery cooling demand will reduce the refrigerant flow rate on the cab cooling circuit, thus reducing the comfort of the cab.

[0081] This embodiment employs a stepped, gradual response to the battery-side cooling demand, avoiding a sudden decrease in refrigerant flow in the cab cooling circuit that could negatively impact cab comfort. The response to the battery-side cooling demand includes the battery-side compressor speed response and the battery-side second electronic expansion valve step size response, such as... Figure 4 As shown.

[0082] The response to battery-side cooling demand includes the battery-side compressor speed response, and the specific steps are as follows:

[0083] First, the compressor runs at speed N1 for t1 seconds;

[0084] Then, the rotation speed is N2 and the running time is t2 seconds;

[0085] Then run at speed N3 for t3 seconds;

[0086] Finally, the rotation speed is increased to N4 and kept operating;

[0087] wherein, N1<N2<N3<N4, N4 is the demanded rotation speed of the compressor, and the demanded rotation speed of the compressor is obtained by querying a Map table according to the difference between the water temperature at the battery coolant inlet and the target water temperature.

[0088] The response to the battery-side cooling demand includes a step response of the second electronic expansion valve, and the specific steps are as follows:

[0089] an initial step S1 of the second electronic expansion valve on the battery side;

[0090] increase the step by S2 every t4 seconds, and the duration is t5 seconds;

[0091] when the rotation speed of the battery-side compressor reaches the demanded rotation speed of the compressor, or when t5 > t1 + t2 + t3, the step of the second electronic expansion valve on the battery side is increased to S3;

[0092] wherein, S1<S2<S3, and S3 is the demanded step of the second electronic expansion valve on the battery side. The demanded step of the second electronic expansion valve on the battery side is based on the actual suction superheat T on the battery side Batt and the target suction superheat T on the battery side Batt_T the difference is calculated, specifically by inputting the actual suction superheat T on the battery side Batt into a PID control algorithm to obtain the result.

[0093] In order to ensure the safety and sustainability of refrigerant distribution, when the rotation speed of the battery-side compressor reaches the set rotation speed value Nt, the step of the second electronic expansion valve on the battery side is increased; when the step of the second electronic expansion valve on the battery side reaches the set step St, the rotation speed of the battery-side compressor is increased, so as to prevent the step of the second electronic expansion valve on the battery side from increasing to the upper limit and avoid overloaded operation of the compressor.

[0094] In this embodiment, when a sudden battery-side cooling demand needs to be responded to at a certain moment during the process of responding to the cab-side cooling demand, the battery-side cooling demand is responded step by step in a stepped manner, which avoids the sudden reduction of the refrigerant flow in the cab cooling circuit that affects the comfort of the cab, can maintain the battery within a suitable temperature range, and achieves the purpose of prioritizing the comfort of the cab.

[0095] Embodiment 4

[0096] This embodiment is an embodiment of a refrigerant flow distribution control system for an integrated thermal management system, which is used to implement the refrigerant flow distribution control method for an integrated thermal management system according to any one of Embodiments 1 to 3, comprising:

[0097] The data acquisition module is used to collect data on the cab interior temperature, average battery temperature, battery coolant inlet water temperature, driver-side cooling circuit low-pressure side pressure and temperature, and battery-side cooling circuit low-pressure side pressure and temperature.

[0098] Setting module: Used to set and maintain the target intake superheat T on the cab side. dri_T And for adjusting the target intake superheat T on the battery side according to vehicle operating conditions, average battery temperature, and battery coolant inlet temperature. Batt_T ;

[0099] Calculation module: Used to calculate the actual intake superheat T on the cab side based on the low-pressure side pressure and temperature values ​​of the refrigerant in the driver's side cooling circuit. dri And used to calculate the actual intake superheat T on the battery side based on the low-pressure side pressure and temperature values ​​of the refrigerant in the battery-side cooling circuit. Batt ;

[0100] Comparison and Judgment Module: Used to compare the actual intake superheat T on the cab side. dri The target intake superheat T on the cab side dri_T Relative size, used to compare the actual intake superheat T on the battery side. Batt With battery-side target intake superheat T Batt_T The relative size, and whether to respond to the cooling demand on the battery side based on the average battery temperature and the cab interior temperature;

[0101] Control module: Used to receive and respond to the cooling demand signal from the cab side. When the actual intake superheat T on the cab side... dri Less than the target intake superheat T on the cab side dri_T Then reduce the step size of the first electronic expansion valve on the cab side; when the actual intake superheat value T on the cab side... dri Greater than the target intake superheat T on the cab side dri_T Then, the step size of the first electronic expansion valve on the cab side is increased; and it is used to receive and respond to the battery-side cooling demand signal, when the actual intake superheat T on the battery side... Batt Less than the target intake superheat T on the battery side Batt_T Then reduce the step size of the second electronic expansion valve on the battery side; when the actual intake superheat T on the battery side... Batt Greater than the target intake superheat T on the battery side Batt_T This increases the step size of the second electronic expansion valve on the battery side.

[0102] In this embodiment, the refrigerant flow rates of the cab cooling circuit and the battery cooling circuit are allocated by setting the target intake superheat on the cab side and the target intake superheat on the battery side. The target intake superheat on the cab side is set to a certain value, while the target intake superheat on the battery side is adjusted according to the vehicle operating conditions, the average battery temperature, and the battery coolant inlet water temperature. This can effectively adjust the step size of the first electronic expansion valve on the cab side and the step size of the second electronic expansion valve on the battery side, so that the battery can be maintained within a suitable temperature range while prioritizing the comfort of the cab.

[0103] In the specific implementation of the above embodiments, the technical features can be combined in any non-contradictory way. For the sake of brevity, not all possible combinations of the above technical features are described. However, as long as the combination of these technical features is not contradictory, it should be considered to be within the scope of this specification.

[0104] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A refrigerant flow distribution and control method for an integrated thermal management system, characterized in that, comprising the following steps: collecting a cab indoor temperature, a battery average temperature, a battery coolant inlet water temperature, a refrigerant low-pressure side pressure value and temperature value of a driver-side cooling circuit, and a refrigerant low-pressure side pressure value and temperature value of a battery-side cooling circuit; Set and maintain the target intake superheat T on the cab side. dri_T T1 is the actual intake superheat T on the cab side, calculated based on the low-pressure side pressure and temperature values ​​of the refrigerant in the driver's side cooling circuit. dri ; Adjust the target intake superheat T on the battery side according to vehicle operating conditions, average battery temperature, and battery coolant inlet temperature. Batt_T The actual intake superheat T on the battery side is calculated based on the pressure and temperature values ​​of the refrigerant on the low-pressure side of the battery-side cooling circuit. Batt ; If a cooling demand signal is received from the cab side, the following steps are taken to respond to the cab side cooling demand: When the actual intake superheat T on the cab side... dri Less than the target intake superheat T on the cab side dri_T Then reduce the step size of the first electronic expansion valve on the cab side; when the actual intake superheat value T on the cab side... dri Greater than the target intake superheat T on the cab side dri_T Then increase the step size of the first electronic expansion valve on the cab side; If a battery-side cooling demand signal is received, determine whether to respond to the battery-side cooling demand based on the average battery temperature and the cab interior temperature; if responding to the battery-side cooling demand, proceed as follows: when the actual intake superheat T on the battery side... Batt Less than the target intake superheat T on the battery side Batt_T Then reduce the step size of the second electronic expansion valve on the battery side; when the actual superheat T of the battery side is... Batt Greater than the target intake superheat T on the battery side Batt_T Then increase the step size of the second electronic expansion valve on the battery side; When the vehicle is in charging mode, set the target intake superheat T on the battery side. Batt_T For T5, T1 <T5; When the vehicle is in driving condition, the target intake superheat T on the battery side is determined based on the average battery temperature and the battery coolant inlet temperature. Batt_T : If the average battery temperature T avg Greater than the first set average temperature T a1 And the battery coolant inlet water temperature T cool Greater than the first set water temperature T c1 Battery-side target intake superheat T Batt_T Designated as T2; If the average battery temperature T avg Greater than the second set average temperature T a2 And the battery coolant inlet water temperature T cool Greater than the second set water temperature T c2 Battery-side target intake superheat T Batt_T Designated as T3; If the average battery temperature T avg Less than the third set average temperature T a3 Or the battery coolant inlet water temperature T cool Less than the third set water temperature T c3 Battery-side target intake superheat T Batt_T Designated as T4; The relationship between the target intake superheat value, the average battery temperature, and the battery coolant inlet temperature is as follows: T1 <T5<T2<T3<T4;T a1 >T a2 >T a3 ;T c1 =T c2 >T c3 .

2. The refrigerant flow distribution control method for the integrated thermal management system according to claim 1, characterized in that, when there are both a battery-side cooling requirement and a cab-side cooling requirement, determining whether to respond to the battery-side cooling requirement according to the cab indoor temperature and the battery average temperature: If the average battery temperature is less than T a4 The temperature inside the driver's cab is greater than T. c4 The battery-side cooling demand will not be responded to temporarily until the cab interior temperature drops to T. c5 Then, respond to the cooling needs on the battery side; If the average battery temperature rises to T a5 Then it will immediately respond to the cooling demand on the battery side; Wherein: T a4 <T a5 T c4 >T c5 .

3. The refrigerant flow distribution control method for the integrated thermal management system according to claim 1, characterized in that, when a battery-side cooling requirement that suddenly intervenes needs to be responded to at a certain moment during the process of responding to the cab-side cooling requirement, the battery-side cooling requirement is responded step by step in a stepped manner.

4. The refrigerant flow distribution control method for the integrated thermal management system according to claim 3, characterized in that, the response to the battery-side cooling requirement comprises a battery-side compressor rotation speed response, and the specific steps are as follows: first, the compressor operates at a rotation speed N1 for a time period of t1 seconds; then it operates at a rotation speed N2 for a time period of t2 seconds; then it operates at a rotation speed N3 for a time period of t3 seconds; finally, the rotation speed is increased to N4 and continues to operate; wherein N1<N2<N3<N4, and N4 is a required rotation speed of the compressor.

5. The refrigerant flow distribution and control method for the integrated thermal management system according to claim 4, characterized in that, the response to the battery-side cooling requirement comprises a step response of a second electronic expansion valve, and the specific steps are as follows: an initial step of the battery-side second electronic expansion valve is S1; the step is increased by S2 every t4 seconds, and the duration is t5 seconds; when the rotation speed of the battery-side compressor reaches the required rotation speed of the compressor, or when t5>t1+t2+t3, the step of the battery-side second electronic expansion valve is increased to S3; wherein S1<S2<S3, and S3 is a required step of the battery-side second electronic expansion valve.

6. The refrigerant flow distribution control method for the integrated thermal management system according to claim 5, characterized in that, The required compressor speed is obtained by querying a Map table based on the difference between the battery coolant inlet temperature and the target temperature. The required step size of the second electronic expansion valve on the battery side is based on the actual suction superheat T on the battery side. Batt With battery-side target intake superheat T Batt_T The difference was calculated.

7. The refrigerant flow distribution control method for the integrated thermal management system according to any one of claims 3 to 6, characterized in that, when the rotation speed of the battery-side compressor reaches a set rotation speed value Nt, the step of the battery-side second electronic expansion valve is increased; when the step of the battery-side second electronic expansion valve reaches a set step St, the rotation speed of the battery-side compressor is increased.

8. A system for implementing the refrigerant flow distribution control method of the integrated thermal management system according to any one of claims 1 to 7, characterized in that, comprising: an acquisition module, configured to acquire a cab indoor temperature, a battery average temperature, a battery coolant inlet water temperature, a refrigerant low-pressure side pressure value and temperature value of a driver-side cooling circuit, and a refrigerant low-pressure side pressure value and temperature value of a battery-side cooling circuit; Setting module: Used to set and maintain the target intake superheat T on the cab side. dri_T And for adjusting the target intake superheat T on the battery side according to vehicle operating conditions, average battery temperature, and battery coolant inlet temperature. Batt_T ; Calculation module: Used to calculate the actual intake superheat T on the cab side based on the low-pressure side pressure and temperature values ​​of the refrigerant in the driver's side cooling circuit. dri And used to calculate the actual intake superheat T on the battery side based on the low-pressure side pressure and temperature values ​​of the refrigerant in the battery-side cooling circuit. Batt ; Comparison and Judgment Module: Used to compare the actual intake superheat T on the cab side. dri The target intake superheat T on the cab side dri_T Relative size, used to compare the actual intake superheat T on the battery side. Batt With battery-side target intake superheat T Batt_T The relative size, and whether to respond to the cooling demand on the battery side based on the average battery temperature and the cab interior temperature; Control module: Used to receive and respond to the cooling demand signal from the cab side. When the actual intake superheat T on the cab side... dri Less than the target intake superheat T on the cab side dri_T Then reduce the step size of the first electronic expansion valve on the cab side; when the actual intake superheat value T on the cab side... dri Greater than the target intake superheat T on the cab side dri_T Then, the step size of the first electronic expansion valve on the cab side is increased; and it is used to receive and respond to the battery-side cooling demand signal, when the actual intake superheat T on the battery side... Batt Less than the target intake superheat T on the battery side Batt_T Then reduce the step size of the second electronic expansion valve on the battery side; when the actual superheat T of the battery side is... dri Greater than the target intake superheat T on the battery side Batt_T This increases the step size of the second electronic expansion valve on the battery side.

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