Cooling control system of hybrid power system and control method thereof

Abstract

The invention discloses a cooling control system of a hybrid power system and a control method of the cooling control system. The cooling control system is located at the front end of a vehicle and divides the front end of the vehicle into an upper-layer area, a middle-layer area and a bottom-layer area in the direction from a front machine cover of the vehicle to a chassis. The heat dissipation module comprises a first radiator, a plate heat exchanger, a battery liquid cooling flow path and a second radiator which are communicated through a circulating flow path; the first radiator, the battery liquid cooling flow path and the second radiator are sequentially arranged in the upper-layer area, the middle-layer area and the bottom-layer area from top to bottom, so that a vehicle can be respectively led into radiating elements in the three areas in a windward manner according to the angle of the liftable guide plate; the liftable guide plate is provided with positions which are inclined downwards and form angles of 0 degree, 20-30 degrees, 45 degrees and 90 degrees with the front bumper, and the control module is used for controlling the execution module according to parameters monitored by the sensing module, so that the upper layer area, the middle layer area and the bottom layer area are subjected to heat dissipation and cooling.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of hybrid vehicle thermal management, in particular to a cooling control system of a hybrid power system and a control method thereof. BACKGROUND

[0002] As an intermediate product of the transition from traditional power to new energy power, the hybrid power system gradually becomes a popular trend in current automobile development due to its advantages of various configurations, outstanding energy-saving effect and excellent power performance. Compared with conventional vehicles, hybrid vehicles increase components such as power batteries and power motors, and the temperature management performance of the power battery as one of the key components of the hybrid vehicle is directly related to the charging and discharging performance and even the safety of the power battery, thereby directly related to the fuel economy, power performance and safety of the whole vehicle.

[0003] In the traditional hybrid thermal management system, the cooling scheme generally adopts a "double-loop independent cooling" mode, that is, the engine high-temperature loop and the electric drive low-temperature loop are completely independently arranged, which results in many technical defects. For example, in the traditional hybrid system, the engine coolant is directly cooled by the main radiator, and the battery needs to be additionally heated when starting at low temperature, which causes the engine waste heat to be unable to be utilized by the battery or the motor, and there are problems of thermal management fragmentation and waste of waste heat; the heat generation of the electric drive system increases dramatically under high load conditions (such as the motor temperature can reach 150℃ when continuously climbing), but the heat dissipation power of the independent low-temperature radiator is limited, and the traditional mechanical water pump cannot adjust the flow according to the real-time heat dissipation demand, which easily causes insufficient cooling or excessive cooling, resulting in performance degradation, and there is a high-load heat dissipation bottleneck; in addition, the traditional hybrid system independently requires multiple radiators, water pumps and expansion tanks, which increases the number of components, occupies a large space, and has problems of system complexity and high cost.

[0004] In addition, in the existing hybrid vehicle thermal management system, each thermal management system is independent of each other, not only resulting in large air inlet resistance and insufficient heat dissipation capacity, but also in a low-temperature environment, since the charging and discharging power of the power battery is greatly affected by temperature, especially the charging and discharging power of the power battery at low temperature is often greatly reduced, which seriously affects the power performance and fuel-saving ability of the vehicle. Therefore, there is an urgent need for a hybrid power system cooling scheme that can solve the above problems. SUMMARY

[0005] In view of the problems existing in the prior art, the present application provides a cooling control system of a hybrid power system and a control method thereof. The cooling control system adopts a three-layer heat dissipation structure arranged in a vertical direction from top to bottom, and effectively utilizes the air flow resources in the vehicle driving process through the reasonable layout of the first radiator, the battery liquid cooling flow path and the second radiator.

[0006] The first aspect of the present application is to provide a cooling control system of a hybrid power system, which is located at the front end of a vehicle and divides the front end of the vehicle into an upper region, a middle region and a bottom region from the front hood to the chassis; the cooling control system comprises a heat dissipation module, a sensing module, a control module and an execution module;

[0007] The heat dissipation module comprises a first radiator, a plate heat exchanger, a battery liquid cooling circuit and a second radiator which are connected by a circulating flow path; the first radiator, the battery liquid cooling circuit and the second radiator are arranged in the upper region, the middle region and the bottom region from top to bottom in the vertical direction from the front hood to the chassis, so that the heat dissipation elements in the three regions can be respectively passed into by the vehicle according to the angle of the liftable deflector plate;

[0008] The sensing module comprises a vehicle speed sensor, an engine coolant temperature sensor and a power battery temperature sensor; the vehicle speed sensor is arranged at the front of the windward surface of the first radiator, the engine coolant temperature sensor is arranged at the outlet of the coolant circulation loop inside the engine, and the power battery temperature sensor is arranged inside the power battery pack;

[0009] The execution module comprises a liftable deflector plate, a high-temperature temperature control valve, a low-temperature temperature control valve, a first three-way valve, a second three-way valve, a third three-way valve, a fourth three-way valve and a fifth three-way valve;

[0010] The liftable deflector plate has a first angle position, a second angle position, a third angle position and a fourth angle position, wherein the first angle position is the vertical position of the liftable deflector plate relative to the ground, the second angle position is 20°-30° between the liftable deflector plate and the front bumper, the third angle position is 45° between the liftable deflector plate and the front bumper, and the fourth angle position is 90° between the liftable deflector plate and the front bumper;

[0011] The high-temperature temperature control valve is used to heat the cooling liquid flowing therethrough to 80℃, and the low-temperature temperature control valve is used to cool the cooling liquid flowing therethrough to 35-40℃;

[0012] The control module is used to control the execution module according to the parameters monitored by the sensing module, so as to perform heat dissipation and cooling on the upper region, the middle region and the bottom region.

[0013] Further, when the liftable deflector plate is located at the second angle position, 80% of the oncoming airflow is guided towards the upper region, and the middle region retains 20% of the remaining flow;

[0014] When the liftable deflector plate is located at the third angle position, 60% of the oncoming airflow is guided towards the middle region;

[0015] When the liftable deflector is in the fourth angle position, the middle layer and the bottom layer are ventilated, and the middle layer and the bottom layer form a series airflow channel.

[0016] Further, the first radiator is located at the side of the engine facing the front end of the vehicle, and the cooling liquid circulation loop inside the engine is cooled by the airflow at the top of the windward surface; the battery liquid cooling flow path is located at the bottom of the power battery pack, and is used to provide temperature management for the power battery pack, and the battery liquid cooling flow path can reduce cooling energy consumption by using the airflow preliminarily cooled by the first radiator; the second radiator is located near the drive motor, and is used to cool the drive motor, the inverter and the electronic control unit.

[0017] Further, the first radiator is a finned radiator, including oppositely arranged windward surfaces and leeward surfaces, the windward surfaces face the front end of the vehicle, and the fin spacing at the windward surfaces is 1.5-2mm, and the fin spacing at the leeward surfaces is 3-3.5mm.

[0018] Further, the working process of the liftable deflector includes:

[0019] When the vehicle speed is ≤40km / h, the liftable deflector maintains the first angle position;

[0020] When the vehicle speed is 40km / h the current vehicle speed 60km / h, and the driving mode is the pure electric driving mode, and the power battery temperature sensor detects that the temperature inside the power battery pack is greater than 35℃, the liftable deflector is adjusted to the third angle position;

[0021] When the vehicle speed is 60km / h the current vehicle speed 90km / h, and the cooling liquid temperature at the outlet of the cooling liquid circulation loop inside the engine is greater than 105℃, the liftable deflector is adjusted to the second angle position;

[0022] If the battery management system (BMS) detects that the discharge current >100A or the charging power >50kW, the liftable deflector is controlled to be completely lowered to the fourth angle (angle 90°) to ventilate the middle layer and the bottom layer.

[0023] Further, the cooling control system further includes a cooling fan, the cooling fan is located at the leeward surface of the first radiator, when the liftable deflector maintains the first angle, the cooling fan is not started; when the liftable deflector is in the second angle position, the cooling fan rotates at 3000rpm; when the liftable deflector is in the third angle position, the cooling fan rotates at 2400rpm; when the liftable deflector is in the fourth angle position, the cooling fan rotates at 1500rpm or below.

[0024] The second aspect of the present application provides a control method of the cooling control system of the hybrid system, comprising:

[0025] After the vehicle starts, the sensing module monitors in real time and uploads data to the control module, and the liftable deflector plate maintains the first angle position;

[0026] Under the conditions of cold start and low load of the vehicle, the vehicle is in pure electric mode, the liftable deflector plate maintains the first angle position, the first three-way valve, the second three-way valve, the fourth three-way valve, the fifth three-way valve, the low-temperature temperature control valve, and the plate heat exchanger are opened, and the circulation of the small circulation flow path is performed.

[0027] Under the conditions of medium load of the vehicle, the vehicle is in hybrid mode, the engine coolant temperature sensor monitors that the engine coolant temperature is less than 70°C, and the battery temperature is greater than 35°C, the liftable deflector plate is in the third angle position, the first three-way valve, the second three-way valve, the third three-way valve, the fourth three-way valve, the fifth three-way valve, the high-temperature temperature control valve, the second radiator, the low-temperature temperature control valve, and the plate heat exchanger are opened, and the circulation of the medium and high load circulation flow path is performed; at this time, the plate heat exchanger does not work, and the coolant only flows through the plate heat exchanger;

[0028] Under the conditions of medium load of the vehicle, the vehicle is in hybrid mode, and the engine coolant temperature sensor monitors that the engine coolant temperature is greater than or equal to 80°C and the power battery temperature sensor monitors that the temperature in the power battery pack is less than 25°C, the liftable deflector plate 1 is in the second angle, and the medium and high load circulation flow path is circulated; at this time, the plate heat exchanger is opened for heat exchange;

[0029] Under the conditions of high load of the vehicle in hybrid mode, the liftable deflector plate is in the first angle or the second angle, and further, the small circulation flow path is: the coolant from the first radiator passes through the first radiator coolant outlet, enters the second three-way valve through the first three-way valve, is divided into two branches at the second three-way valve, one branch passes through the second radiator coolant inlet, the second radiator, the second radiator coolant outlet, the fourth three-way valve, and the plate heat exchanger, enters the fifth three-way valve, and the other branch passes through the low-temperature temperature control valve, the plate heat exchanger, the battery coolant inlet, the battery liquid cooling flow path, and the battery coolant outlet, and enters the fifth three-way valve; the two branches are combined at the fifth three-way valve and enter the first radiator through the first radiator coolant inlet, thereby completing a small circulation.

[0030] Further, the medium and high load circulation flow path is: the cooling liquid from the first radiator is divided into two paths through the first radiator cooling liquid outlet and the first three-way valve, one branch passes through the high-temperature temperature control valve, the engine cooling liquid inlet, enters the engine internal cooling flow path, circulates and cools in the engine, and then flows out from the engine cooling liquid outlet at the other end of the engine; then passes through the third three-way valve and the fourth three-way valve to enter the plate heat exchanger, then enters the battery liquid cooling flow path through the battery cooling liquid inlet, circulates and cools, and flows out from the battery cooling liquid outlet to enter the fifth three-way valve; the other branch passes through the second three-way valve and is divided into two paths again, one branch passes through the second radiator cooling liquid inlet, the second radiator, the second radiator cooling liquid outlet, the fourth three-way valve, the plate heat exchanger, enters the fifth three-way valve, and the other branch passes through the low-temperature temperature control valve, the plate heat exchanger, the battery cooling liquid inlet, the battery liquid cooling flow path, the battery cooling liquid outlet, and enters the fifth three-way valve; the three branches are combined in the fifth three-way valve and then enter the first radiator through the first radiator cooling liquid inlet, thereby completing one cycle.

[0031] The beneficial effects of the present application are:

[0032] 1. The present application adopts a three-layer heat dissipation structure arranged in a vertical direction from top to bottom, and through the reasonable layout of the first radiator, the battery liquid cooling flow path and the second radiator, the airflow resources during vehicle driving are effectively utilized, and the heat dissipation efficiency is significantly improved.

[0033] 2. The plate heat exchanger is arranged between the first radiator and the battery liquid cooling flow path to realize cross-system heat management.

[0034] 3. The present application realizes real-time monitoring of vehicle speed and cooling liquid temperature through the sensing module, can dynamically adjust the guide vane angle and cooling strategy according to different working conditions, and improves the controllability and adaptability of the heat dissipation system. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 is a cooling control system structure diagram of the hybrid power system;

[0036] Figure 2 is a local schematic view of the first radiator in the cooling control system of the hybrid power system;

[0037] Figure 3 is a cross-sectional view of the power battery pack involved in the cooling control system of the hybrid power system;

[0038] Figure 4 is a control method flow chart of the ventilation control sub-module of the cooling control system of the hybrid power system;

[0039] Figure 5is a side view of a vehicle equipped with a cooling control system of the hybrid power system, wherein the position of the heat dissipation module located at the front of the vehicle is shown.

[0040] wherein,

[0041] 1: Lifting deflector; 2: Vehicle speed sensor; 3: First radiator; 4: First radiator coolant outlet; 5: High temperature temperature control valve; 6: Second radiator; 7: Second radiator coolant inlet; 8: Motor; 9: Engine coolant inlet; 10: Engine coolant temperature sensor; 11: Engine coolant outlet; 12: Plate heat exchanger; 13: Battery coolant inlet; 14: Water pump; 15: Second radiator coolant outlet; 16: Power battery pack; 17: Battery coolant outlet; 18: Low temperature temperature control valve; 19: Cooling fan; 20: First radiator coolant inlet; 21: Windward surface; 22: Leeward surface; 23: Intumescent fire retardant; 24: Battery cell; 26: Smoke sensor; 30: First three-way valve; 31: Second three-way valve; 32: Third three-way valve; 33: Fourth three-way valve; 34: Fifth three-way valve. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solutions, beneficial effects and significant progress of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings provided in the examples of the present application. Obviously, all the described embodiments are only part of the embodiments of the present application, not all the embodiments; based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor belong to the scope of protection of the present application.

[0043] In the description of the present application, unless otherwise explicitly specified and limited, the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance; the term "multiple" means two or more than two; unless otherwise specified or explained, the terms "connection", "fixation" and the like should be understood broadly, for example, "connection" can be fixed connection, or detachable connection, or integrally connected, or electrically connected; "connection" can be directly connected, or indirectly connected through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0044] As Figure 1 shown, a cooling control system of a vehicle hybrid power system includes a lifting deflector 1, a heat dissipation module, a sensing module, a control module, an execution module and a circulating flow path.

[0045] The heat dissipation module is located at the front end of the vehicle and comprises a first radiator 3, a plate heat exchanger 12, a battery liquid cooling circuit and a second radiator 6 which are connected by a circulating flow path; the front end of the vehicle is vertically divided into an upper layer region, a middle layer region and a bottom layer region from the top to the bottom of the vehicle front hood; wherein the main part of the first radiator 3 and the cooling fan 19 are located in the upper layer region, the battery liquid cooling circuit is mainly located in the middle layer region, and the main part of the second radiator 6 is located in the bottom layer region. Here, "located" does not mean that the first radiator 3, the battery liquid cooling circuit and the second radiator 6 are completely unobstructed and located only in the three regions respectively, but only that their main parts are located in the three regions respectively, having a spatial up-down positional relationship, so that the wind of the liftable guide plate 1 can be respectively introduced into the heat dissipation devices in the three regions according to the angle when the wind is in the vertical or inclined state.

[0046] As shown in Figure 5 , the first radiator 3, the battery liquid cooling circuit and the second radiator 6 are arranged in three layers of heat dissipation matrix from the top to the bottom of the vehicle front hood vertically to the chassis, and each layer region corresponds to a different cooling object to form a modular heat management network.

[0047] The first radiator 3 is located at the front end of the engine facing the vehicle, and the high-speed airflow at the top of the windward surface is used to dissipate heat of the internal cooling liquid circulation loop of the engine; the battery liquid cooling circuit is located at the bottom of the power battery pack 16 and is used to provide temperature management for the power battery pack 16 to ensure that it works in the best interval of 25-40℃ and avoids high-temperature attenuation or low-temperature performance decline; moreover, the battery liquid cooling circuit can reduce cooling energy consumption by using the airflow after preliminary cooling of the first radiator 3; the second radiator located in the bottom layer region is located near the drive motor and is used to cool the drive motor, the inverter and the electronic control unit.

[0048] As shown in Figure 2 , the first radiator 3 is a finned radiator comprising a base pipe and fins arranged on the outer wall of the base pipe. The first radiator 3 comprises an air-facing surface 21 and a leeward surface 22 arranged oppositely, the air-facing surface faces the front end of the vehicle, and the fin spacing at the air-facing surface 21 is 1.8mm, and the fin spacing at the leeward surface 22 is 3.2mm. The dense fins arranged on the air-facing surface can increase the heat exchange area and strengthen the heat transfer efficiency of the airflow and the cooling liquid, while the sparse fins arranged on the leeward surface 22 can reduce the air flow resistance, improve the heat dissipation performance and reduce the wind resistance loss, realizing the synergistic optimization of high-efficiency heat exchange and low-resistance operation.

[0049] The first radiator 3 undertakes the heat dissipation of the engine internal coolant circulation loop. Of course in other embodiments, the engine internals including cylinder liners, cylinder heads, cylinder blocks, turbochargers, etc. can also be cooled. Moreover, a cooling fan 19 is provided 30 mm away from the leeward side of the first radiator 3 for assisting heat dissipation at low speed or quickly taking away heat when the engine coolant temperature > 95℃.

[0050] As shown in Figure 3 The power battery pack 16 includes a plurality of battery monomers 24 arranged in an array, and a battery liquid cooling flow path (not shown in the figure) is laid flat on the bottom of the battery monomers 24. The battery liquid cooling flow path is an S-shaped liquid cooling pipe and is laid flat against the bottom of the battery monomers 24. Moreover, a smoke sensor 26 is provided on the side wall of the power battery pack 16, and an intumescent flame retardant 23 is provided on the inner wall of the power battery pack 16.

[0051] The second radiator 6 is a conventional finned radiator for cooling the drive motor, inverter and electronic control unit of the vehicle to avoid overheating during high-power operation.

[0052] The sensing module includes a vehicle speed sensor, an engine coolant temperature sensor and a power battery temperature sensor. The vehicle speed sensor is provided at the front of the windward side of the first radiator 3 at the front end of the vehicle for detecting the vehicle speed, the engine coolant temperature sensor 10 is provided at the engine coolant outlet 11 for detecting the engine coolant temperature, and the power battery temperature sensor is provided in the power battery pack for detecting the power battery temperature.

[0053] The execution module includes a liftable deflector 1, a high-temperature temperature control valve 5, a low-temperature temperature control valve 18, a first three-way valve 30, a second three-way valve 31, a third three-way valve 32, a fourth three-way valve 33 and a fifth three-way valve 34. The liftable deflector 1 is inclined downward and has a first angle position, a second angle position, a third angle position and a fourth angle position. The angle referred to here is the angle between the front bumper / front license plate at the frontmost end of the vehicle and the deflector. The first angle position corresponds to the vertical position relative to the ground (angle 0°), the second angle position corresponds to the near-vertical position (angle 20°-30°), the third angle position corresponds to the 45° position, and the fourth angle position corresponds to the 90° position (i.e. parallel to the ground). The liftable deflector 1 is provided at the front of the windward side of the first radiator 3 at the front end of the vehicle for changing the angle of the liftable deflector to the first angle position, the second angle position, the third angle position or the fourth angle position according to the instructions of the control module.

[0054] The first three-way valve 30 is connected with the first radiator cooling liquid outlet 4, the high-temperature temperature control valve 5 and the second three-way valve 31 respectively; the second three-way valve 31 is connected with the first three-way valve 30, the low-temperature temperature control valve 18 and the second radiator cooling liquid inlet 7 respectively; the third three-way valve 32 is connected with the engine cooling liquid inlet 9, the engine cooling liquid outlet 11 and the fourth three-way valve 33 respectively. The fourth three-way valve 33 is connected with the second radiator cooling liquid outlet 15, the plate heat exchanger 12 and the third three-way valve 32 respectively. The fifth three-way valve 34 is connected with the battery cooling liquid outlet 17, the first radiator cooling liquid inlet 20 and the plate heat exchanger 12 respectively.

[0055] The high-temperature temperature control valve and the low-temperature temperature control valve are opened or closed according to the instruction of the control module to control the distribution of the cooling liquid, wherein the high-temperature temperature control valve 5 can make the cooling liquid flowing therethrough to be heated to 80℃, and the low-temperature temperature control valve 18 can make the cooling liquid flowing therethrough to be cooled to 35-40℃.

[0056] The control module comprises an electronic control unit ECU, and the ECU controls the execution module according to the parameters monitored by the sensing module, so as to realize intelligent management of the cooling system. The control module further comprises a ventilation control sub-module and a flow path control sub-module.

[0057] The flow path control sub-module comprises a small cycle flow path and a medium / high load cycle flow path.

[0058] The small cycle flow path is adopted in the low load working condition in the pure electric mode, wherein the small cycle flow path is as follows: the cooling liquid from the first radiator 3 passes through the first radiator cooling liquid outlet 4, then passes through the first three-way valve 30 to enter the second three-way valve 31, and is divided into two branches in the second three-way valve 31, one branch passes through the second radiator cooling liquid inlet 7, the second radiator 6, the second radiator cooling liquid outlet 15, the fourth three-way valve 33, the plate heat exchanger 12, enters the fifth three-way valve 34, and the other branch passes through the low-temperature temperature control valve 18, the plate heat exchanger 12 (the plate heat exchanger 12 comprises two inlets located below and on the left side as shown in the figure and two outlets located on the right side and above as shown in the figure), the battery cooling liquid inlet 13, the battery liquid cooling flow path, the battery cooling liquid outlet 17, and enters the fifth three-way valve 34; the two branches are combined in the fifth three-way valve 34 and then enter the first radiator 3 through the first radiator cooling liquid inlet 20, so as to complete a small cycle.

[0059] The circulating flow path of the medium and high load circulating flow path in the hybrid mode comprises: the cooling liquid from the first radiator 3 is divided into two paths after the first radiator cooling liquid outlet 4 and the first three-way valve 30, one branch passes through the high-temperature temperature control valve 5, the engine cooling liquid inlet 9, and then enters the internal cooling flow path of the engine to circulate and cool in the engine, and then flows out from the engine cooling liquid outlet 11 at the other end of the engine; then enters the plate heat exchanger 12 through the third three-way valve 32 and the fourth three-way valve 33, then enters the battery liquid cooling flow path through the battery cooling liquid inlet 13, and flows out from the battery cooling liquid outlet 17 to enter the fifth three-way valve 34; the other branch passes through the second three-way valve 31 and is divided into two paths, one branch passes through the second radiator cooling liquid inlet 7, the second radiator 6, the second radiator cooling liquid outlet 15, the fourth three-way valve 33, the plate heat exchanger 12, and enters the fifth three-way valve 34, and the other branch passes through the low-temperature temperature control valve 18, the plate heat exchanger 12, the battery cooling liquid inlet 13, the battery liquid cooling flow path, the battery cooling liquid outlet 17, and enters the fifth three-way valve 34; the three branches are combined in the fifth three-way valve 34 and then enter the first radiator 3 through the first radiator cooling liquid inlet 20, thereby completing one cycle.

[0060] The medium and high load circulating flow path refers to that in the hybrid mode, the medium load circulating flow path is the same as the high load circulating flow path, except that the plate heat exchanger 12 plays different roles in the two circulating flow paths. The plate heat exchanger 12 between the first radiator 3 and the battery liquid cooling flow path is a core component for realizing cross-system heat management. In the medium and high load circulating flow paths under the medium load working condition, the plate heat exchanger 12 is used to warm up the battery cooling liquid with the engine waste heat to reduce the temperature difference; in the medium and high load circulating flow paths under the high load working condition, the plate heat exchanger 12 is used to reduce the temperature difference by absorbing the heat of the high-temperature cooling liquid of the engine, thereby realizing rapid heat dissipation.

[0061] As shown in Figure 4 The working process of the ventilation control sub-module includes:

[0062] After the vehicle starts, the sensing module monitors and uploads data to the control module in real time; the liftable guide vane 1 defaults to maintain the first angle when the vehicle starts, that is, the vertical position relative to the ground, and the cooling fan is not turned on;

[0063] The vehicle speed sensor monitors the vehicle speed, and if the vehicle speed is less than or equal to 40 km / h (in a low load working condition), the liftable guide vane 1 remains closed and maintains the first angle position of the liftable guide vane 1; otherwise, the next step is continued;

[0064] If the vehicle speed is greater than 40 km / h The current vehicle speed 60km / h, and the driving mode is the pure electric driving mode, and the power battery temperature sensor monitors that the temperature in the power battery pack is greater than 35℃, the middle layer area ventilation is performed, that is, the liftable deflector 1 is controlled to the third angle position (that is, the angle 45° position), and about 60% of the high-speed oncoming airflow is guided to the battery liquid cooling flow path. At this time, the cooling fan rotates at 2400 rpm; otherwise, the judgment is continued;

[0065] If the vehicle speed sensor monitors that the vehicle speed is 60km / h the current vehicle speed 90km / h, and the power battery temperature sensor monitors that the temperature in the power battery pack is greater than 55℃ or the engine coolant temperature sensor 10 monitors that the coolant temperature at the outlet of the cooling liquid circulation loop in the engine is greater than 105℃, the upper layer area ventilation is performed, the liftable deflector 1 is controlled to the second angle position (the angle 20°-30° position), more than 80% of the high-speed oncoming airflow is guided to the first radiator 3, the cooling fan 19 is opened and set to the maximum speed, that is, 3000 rpm; otherwise, the judgment is continued;

[0066] If the battery management system (BMS) detects that the discharge current is >100A or the charging power is >50kW, the liftable deflector 1 is controlled to completely drop to the fourth angle (the angle 90°), the bottom layer area ventilation is performed, the battery liquid cooling flow path in the middle layer and the second radiator 6 in the lower layer area form a series airflow channel, the total air volume is improved, and the vehicle interior bottom airflow is utilized to avoid ground dust blockage;

[0067] If the above conditions are not met, the liftable deflector 1 maintains the first angle.

[0068] The control method of the cooling control system of the hybrid power system comprises:

[0069] After the vehicle is started, the sensing module monitors in real time and uploads data to the control module;

[0070] Under the condition of vehicle cold start and low load (vehicle speed ≤ 40km / h), the vehicle hybrid power system is mainly in pure electric mode, the adjustable guide vane 1 maintains the first angle position, the ECU controls the low-speed operation of the cooling circuit water pump 14 inside the engine, and the speed is 500-800rpm; At the same time, the control module controls the first three-way valve 30, the second three-way valve 31, the fourth three-way valve 33, the fifth three-way valve 34, the low-temperature temperature control valve 18 and the plate heat exchanger 12 to open, and the small circulation flow path is carried out. The cooling liquid from the first radiator 3 passes through the first radiator cooling liquid outlet 4, then enters the second three-way valve 31 through the first three-way valve 30, and is divided into two paths at the second three-way valve 31. One branch passes through the second radiator cooling liquid inlet 7, the second radiator 6, the second radiator cooling liquid outlet 15, the fourth three-way valve 33, the plate heat exchanger 12, and enters the fifth three-way valve 34. The other branch passes through the low-temperature temperature control valve 18, and then passes through the plate heat exchanger 12, the battery cooling liquid inlet 13, the battery liquid cooling flow path, and the battery cooling liquid outlet 17 in turn after the cooling liquid is cooled to 35-40℃. The two branches are combined at the fifth three-way valve 34 and then enter the first radiator 3 through the first radiator cooling liquid inlet 20, thereby completing a small circulation.

[0071] Under the condition of medium load of the vehicle (40km / h Current vehicle speed 60km / h), the vehicle is in hybrid mode, and the engine cooling liquid temperature sensor 10 monitors that the engine cooling liquid temperature <70℃ and the battery temperature >35℃, the adjustable guide vane 1 is in the third angle position (45° position), the first three-way valve 30, the second three-way valve 31, the third three-way valve 32, the fourth three-way valve 33, the fifth three-way valve 34, the high-temperature temperature control valve 5, the second radiator 6, the low-temperature temperature control valve 18 and the plate heat exchanger 12 are opened, and the circulation of the medium and high load circulation flow path is carried out, including:

[0072] The cooling liquid from the first radiator 3 is divided into two paths after the first radiator cooling liquid outlet 4, one branch passes through the high-temperature temperature control valve 5 to increase the temperature of the cooling water to 80℃, and then the cooling water with increased temperature enters the engine cooling liquid inlet 9 to circulate in the cooling flow path inside the engine, and then flows out from the engine cooling liquid outlet 11 at the other end of the engine; then enters the plate heat exchanger 12 through the third three-way valve 32 and the fourth three-way valve 33, and then enters the battery cooling liquid inlet 13 to circulate and cool in the battery cooling flow path, and flows out from the battery cooling liquid outlet 17 into the fifth three-way valve 34; the other branch is divided into two paths through the second three-way valve 31, one branch passes through the second radiator cooling liquid inlet 7, the second radiator 6, the second radiator cooling liquid outlet 15, the fourth three-way valve 33, the plate heat exchanger 12, and enters the fifth three-way valve 34, and the other branch passes through the low-temperature temperature control valve 18, the plate heat exchanger 12, the battery cooling liquid inlet 13, the battery cooling flow path, the battery cooling liquid outlet 17, and enters the fifth three-way valve 34; the three branches are combined in the fifth three-way valve 34 and then enter the first radiator 3 through the first radiator cooling liquid inlet 20, thereby completing a cycle. At this time, the plate heat exchanger 12 does not work, the cooling liquid only flows through the plate heat exchanger 12, and the battery cooling is independently operated to avoid the low-temperature engine absorbing the heat of the battery.

[0073] When the vehicle is in hybrid mode, the engine cooling liquid temperature sensor 10 monitors that the engine cooling liquid temperature is ≥80℃ and the power battery temperature sensor monitors that the temperature in the power battery pack is <25℃, the adjustable guide plate 1 is at the second angle, guiding more than 80% of the high-speed oncoming airflow directly to the first radiator in the upper layer area, and only 20% of the flow is reserved in the middle layer area to maintain the circulation of the medium and high load circulation flow path; at this time, the plate heat exchanger 12 is opened for heat exchange, the engine waste heat is used for preheating the battery to improve the low-temperature charging and discharging efficiency.

[0074] When the vehicle is in hybrid mode and the vehicle is in high load working condition (vehicle speed ≥90km / h or in the scene of climbing, high-speed overtaking, mountain road, trailer driving), the ECU controls the cooling circuit water pump 14 inside the engine to run at full speed, with a speed of 3000-3500rpm; the cooling fan 19 rotates at a speed of 3000rpm, the adjustable guide plate 1 is at the second angle position (20° position), guiding more than 80% of the high-speed oncoming airflow directly to the first radiator in the upper layer engine, and only 20% of the flow is reserved in the middle layer area to quickly reduce the engine cooling liquid temperature by using the strong heat dissipation capacity of the high-speed airflow, avoiding the airflow turbulence caused by high-speed driving to reduce the battery cooling efficiency; at the same time, the medium and high load circulation flow paths are circulated;

[0075] So when the head-on airflow static pressure is high, the liftable guide vane 1 can also be adjusted to the fourth angle position, fully utilize the natural wind cooling, and reduce the cooling fan 19 speed to below 1500 rpm.

[0076] In addition, it should be understood that, although the present specification is described in terms of embodiments, not every embodiment contains only one independent technical solution, the specification is described in this way only for the sake of clarity, the skilled in the art should be the specification as a whole, the technical solutions in the examples can also be properly combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A cooling control system for a hybrid power system, characterized in that, The cooling control system is located at the front of the vehicle and divides the front of the vehicle into an upper region, a middle region, and a bottom region from the hood towards the chassis; the cooling control system includes a heat dissipation module, a sensing module, a control module, and an execution module; The heat dissipation module includes a first radiator (3), a plate heat exchanger (12), a battery liquid cooling flow path, and a second radiator (6) connected by a circulation flow path. The first radiator (3), the battery liquid cooling flow path, and the second radiator (6) are arranged from top to bottom in the upper, middle, and lower layers of the vehicle from the front hood vertically toward the chassis, so that the heat dissipation elements of the vehicle can be directed into the three layers of the vehicle according to the angle of the liftable guide plate (1). The sensing module includes a vehicle speed sensor, an engine coolant temperature sensor, and a power battery temperature sensor; the vehicle speed sensor is located at the front of the first radiator (3), the engine coolant temperature sensor (10) is located at the outlet of the coolant circulation loop inside the engine, and the power battery temperature sensor is located inside the power battery pack. The execution module includes a liftable guide plate (1), a high temperature control valve (5), a low temperature control valve (18), a first three-way valve (30), a second three-way valve (31), a third three-way valve (32), a fourth three-way valve (33), and a fifth three-way valve (34). The liftable guide plate (1) has a first angle position, a second angle position, a third angle position and a fourth angle position, wherein the first angle position is the vertical position of the liftable guide plate (1) relative to the ground, the second angle position is the angle between the liftable guide plate (1) and the front bumper at 20°-30°, the third angle position is the angle between the liftable guide plate (1) and the front bumper at 45°, and the fourth angle position is the angle between the liftable guide plate (1) and the front bumper at 90°. The high-temperature temperature control valve (5) is used to raise the temperature of the flowing coolant to 80°C, and the low-temperature temperature control valve (18) is used to lower the temperature of the flowing coolant to 35-40°C. The control module controls the execution module based on the parameters monitored by the sensing module, thereby dissipating heat and cooling the upper, middle and lower layers.

2. The cooling control system for the hybrid power system according to claim 1, characterized in that, When the liftable deflector (1) is in the second angle position, it guides 80% of the oncoming airflow toward the upper area, while the middle area retains 20% of the residual flow. When the liftable deflector (1) is in the third angle position, it guides 60% of the oncoming airflow toward the middle layer region; When the liftable guide plate (1) is in the fourth angle position, ventilation is carried out in the middle and bottom areas, and the middle and bottom areas form a series airflow channel.

3. The cooling control system for the hybrid power system according to claim 1, characterized in that, The first radiator (3) is located on the side of the engine facing the front of the vehicle, and uses the airflow at the top of the windward side to cool the coolant circulation loop inside the engine; the battery liquid cooling flow path is located at the bottom of the power battery pack (16) and is used to provide temperature management for the power battery pack (16), and the battery liquid cooling flow path can reduce cooling energy consumption by using the airflow after the initial cooling by the first radiator (3); the second radiator (6) is located near the drive motor and is used to cool the drive motor, inverter and electronic control unit.

4. The cooling control system for the hybrid power system according to claim 1, characterized in that, The first radiator (3) is a finned radiator, including a windward side (21) and a leeward side (22) arranged opposite to each other. The windward side (21) faces the front of the vehicle, and the fin spacing at the windward side (21) is 1.5-2mm, while the fin spacing at the leeward side (22) is 3-3.5mm.

5. The cooling control system for the hybrid power system according to claim 1, characterized in that, The working process of the liftable guide plate (1) includes: When the vehicle speed is ≤40km / h, the liftable deflector (1) maintains the first angle position; When the vehicle speed is 40km / h Current speed 60km / h, and the driving mode is pure electric drive mode. When the power battery temperature sensor detects that the temperature inside the power battery pack is greater than 35℃, the lift guide plate (1) can be adjusted to the third angle position. When the vehicle speed is 60km / h Current speed 90km / h, and the coolant temperature at the outlet of the coolant circulation loop inside the engine is greater than 105℃, so the liftable guide plate (1) can be adjusted to the second angle position. If the battery management system detects a discharge current > 100A or a charging power > 50kW, it controls the liftable guide plate (1) to descend to the fourth angle (angle 90°) to ventilate the middle and bottom areas.

6. The cooling control system for the hybrid power system according to claim 1, characterized in that, The cooling control system also includes a cooling fan (19), which is located on the leeward side of the first radiator (3). When the liftable guide plate (1) is maintained at the first angle, the cooling fan (21) does not start; when the liftable guide plate (1) is in the second angle position, the speed of the cooling fan 19 is 3000 rpm; when the liftable guide plate is in the third angle position, the speed of the cooling fan is 2400 rpm; when the liftable guide plate (1) is in the fourth angle position, the speed of the cooling fan (21) is below 1500 rpm.

7. The control method for the cooling control system of the hybrid power system according to claim 1, comprising: After the vehicle starts, the sensor module monitors in real time and uploads the data to the control module, and the liftable guide vane (1) maintains the first angle position; When the vehicle is in a cold start and low load condition, the vehicle is in pure electric mode. The liftable guide plate (1) maintains the first angle position and controls the opening of the first three-way valve (30), the second three-way valve (31), the fourth three-way valve (33), the fifth three-way valve (34), the low temperature temperature control valve (18), and the plate heat exchanger (12) to circulate the small circulation path. When the vehicle is under medium load and in hybrid mode, the engine coolant temperature sensor (10) detects that the engine coolant temperature is <70℃ and the battery temperature is >35℃. The liftable guide plate (1) is in the third angle position, controlling the opening of the first three-way valve (30), the second three-way valve (31), the third three-way valve (32), the fourth three-way valve (33), the fifth three-way valve (34), the high temperature control valve (5), the second radiator (6), the low temperature control valve (18), and the plate heat exchanger (12) to circulate the medium and high load circulation paths. At this time, the plate heat exchanger (12) does not work, and the coolant only flows through the plate heat exchanger (12). When the vehicle is under medium load conditions, the vehicle is in hybrid mode, and the engine coolant temperature sensor (10) detects that the engine coolant temperature is ≥80℃ and the power battery temperature sensor detects that the power battery pack temperature is <25℃, the liftable guide plate (1) is in the second angle to circulate the medium and high load circulation path; at this time, the plate heat exchanger (12) starts heat exchange. When the vehicle is in hybrid mode and under high load conditions, the liftable guide vane (1) is at the first or second angle to circulate the medium and high load circulation path; at this time, the plate heat exchanger (12) starts heat exchange.

8. The control method according to claim 7, characterized in that, The small circulation path is as follows: the coolant from the first radiator (3) enters the second three-way valve (31) through the first radiator coolant outlet (4) and the first three-way valve (30). The second three-way valve (31) splits into two paths. One path passes through the second radiator coolant inlet (7), the second radiator (6), the second radiator coolant outlet (15), the fourth three-way valve (33), the plate heat exchanger (12), and enters the fifth three-way valve (34). The other path passes through the low temperature control valve (18), the plate heat exchanger (12), the battery coolant inlet (13), the battery liquid cooling path, the battery coolant outlet (17), and enters the fifth three-way valve (34). The two paths merge at the fifth three-way valve (34) and enter the first radiator (3) through the first radiator coolant inlet (20), thus completing one small circulation. The medium and high load circulation path is as follows: the coolant from the first radiator (3) is divided into two paths through the first three-way valve (30) after passing through the first radiator coolant outlet (4). One branch passes through the high temperature control valve (5) and the engine coolant inlet (9) to enter the engine internal cooling path for circulation and cooling. Then it flows out from the engine coolant outlet (11) at the other end of the engine. After passing through the third three-way valve (32) and the fourth three-way valve (33), it enters the plate heat exchanger (12). Then it enters the battery liquid cooling path for circulation and cooling through the battery coolant inlet (13) and flows out from the battery coolant outlet (17) to the fifth three-way valve (34). Another branch is divided into two paths via the second three-way valve (31). One branch passes through the second radiator coolant inlet (7), the second radiator (6), the second radiator coolant outlet (15), the fourth three-way valve (33), the plate heat exchanger (12), and enters the fifth three-way valve (34). The other branch passes through the low-temperature temperature control valve (18), the plate heat exchanger (12), the battery coolant inlet (13), the battery liquid cooling flow path, the battery coolant outlet (17), and enters the fifth three-way valve (34). The three branches converge at the fifth three-way valve (34) and enter the first radiator (3) via the first radiator coolant inlet (20), thus completing one cycle.

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