Secondary circuit thermal management system and electric vehicle

Abstract

The present invention relates to the technical field of electric vehicle thermal management, and particularly relates to a secondary loop thermal management system and an electric vehicle, which include a refrigerant loop, a passenger compartment water loop, a battery water loop, and a motor water loop. The refrigerant loop includes a water-cooled evaporator and a water-cooled condenser; the passenger compartment water loop includes a first four-way valve and a second four-way valve. The first interface of the first four-way valve is connected to the first end of the water-cooled evaporator, and its second interface is connected to the third end of the water-cooled condenser. The first interface of the second four-way valve is connected to the fourth end of the water-cooled condenser, and its second interface is connected to the second end of the water-cooled evaporator; the battery water loop is respectively connected to the fourth interface of the first four-way valve and the third interface of the second four-way valve; the motor water loop is respectively connected to the third interface of the first four-way valve and the fourth interface of the second four-way valve; the structure of the present invention is simply designed, with low cost, diverse thermal management modes, and the heat exchange efficiency is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of electric vehicle thermal management, and particularly relates to a secondary loop thermal management system and an electric vehicle. Background Art

[0002] In the field of electric vehicle thermal management technology, the primary loop system is widely used. The primary loop system generally uses a refrigerant (such as R134a) to directly exchange heat with a heat source or a cold source. With the increasingly strict environmental protection regulations, the environmental safety requirements for refrigerants are continuously increasing, and R290, as an environmentally friendly refrigerant, has gradually attracted attention. Due to the flammability of the refrigerant R290, in order to meet the requirements of safety regulations, the secondary loop system has become an option.

[0003] Currently, the existing secondary loop systems have the following defects: (1) The architecture design is usually relatively complex, and more components are required to achieve heat exchange between the refrigerant and the coolant, and between the coolant and the heat source and cold source, increasing the complexity, cost, volume and weight of the system. (2) The thermal management modes are limited, and the combination of heating and cooling modes and dehumidification modes cannot be achieved. (3) Since a coolant is introduced as an intermediate medium, the number of heat exchange links is increased, resulting in a relatively lower heat exchange efficiency compared to the primary loop system, and increasing the energy consumption. (4) In extremely low temperature environments, the relatively low heat exchange efficiency affects the system performance. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: to overcome the deficiencies in the prior art and provide a secondary loop thermal management system and an electric vehicle with a simple structure design, low cost, diverse thermal management modes, and guaranteed heat exchange efficiency.

[0005] The technical solution adopted by the present invention to solve its technical problem is: a secondary loop thermal management system, including a refrigerant loop, the refrigerant loop includes a water-cooled evaporator and a water-cooled condenser, and further includes:

[0006] A passenger compartment water loop for heat exchange in the passenger compartment;

[0007] The passenger compartment water loop includes a first four-way valve and a second four-way valve. The first interface of the first four-way valve is connected to the first end of the water-cooled evaporator, and its second interface is connected to the third end of the water-cooled condenser; the first interface of the second four-way valve is connected to the fourth end of the water-cooled condenser, and its second interface is connected to the second end of the water-cooled evaporator;

[0008] A battery water loop, which is respectively connected to the fourth interface of the first four-way valve and the third interface of the second four-way valve, for heat exchange of the battery;

[0009] and a motor water circuit, which are respectively connected to the third interface of the first four-way valve and the fourth interface of the second four-way valve for heat exchange of the motor;

[0010] The passenger compartment water circuit further includes a low-pressure side water pump, a PTC heater, a first three-way proportional valve, a second three-way proportional valve, a first three-way valve, a heater core, a second three-way valve, a first waterway three-way, a second waterway three-way, a third waterway three-way, a cold air core, a third three-way valve, a fourth waterway three-way, a fifth waterway three-way, and a high-pressure side water pump. The first interface of the first three-way proportional valve is connected to the first end of the water-cooled evaporator through the PTC heater, and its second interface is connected to the first interface of the first four-way valve; the first interface of the second three-way proportional valve is connected to the third end of the water-cooled condenser, and its second interface is connected to the second interface of the first four-way valve; the first interface of the fifth waterway three-way is connected to the second end of the water-cooled evaporator through the low-pressure side water pump, and its second interface is connected to the second interface of the second four-way valve; the first interface of the first waterway three-way is connected to the fourth end of the water-cooled condenser through the high-pressure side water pump, and its second interface is connected to the first interface of the second four-way valve; the first interface of the first three-way valve is connected to the third interface of the second three-way proportional valve, and its second interface is connected to the first interface of the second waterway three-way; the third interface of the first three-way valve is connected to the third interface of the third waterway three-way; one end of the heater core is connected to the second interface of the second waterway three-way, and the other end is connected to the first interface of the second three-way valve; the second interface of the second three-way valve is connected to the third interface of the first waterway three-way, and its third interface is connected to the third interface of the fourth waterway three-way; the first interface of the third waterway three-way is connected to the third interface of the first three-way proportional valve, and its second interface is connected to one end of the cold air core; the first interface of the third three-way valve is connected to the other end of the cold air core, and its second interface is connected to the first interface of the fourth waterway three-way; the second interface of the fourth waterway three-way is connected to the third interface of the fifth waterway three-way.

[0011] Further, the refrigerant circuit further includes a gas-liquid separator, a compressor, and a main electronic expansion valve. The third end of the water-cooled evaporator is sequentially connected to the first end of the water-cooled condenser through the gas-liquid separator and the compressor, and its fourth end is connected to the second end of the water-cooled condenser through the main electronic expansion valve.

[0012] Further, the refrigerant circuit further includes a bypass electronic expansion valve. The third end of the water-cooled evaporator is connected to the first end of the water-cooled condenser through the bypass electronic expansion valve.

[0013] Further, the passenger compartment water circuit further includes a stop valve. The first interface of the stop valve is connected to the third interface of the second waterway three-way, and its second interface is connected to the third interface of the third three-way valve.

[0014] Further, the battery water circuit includes a battery water pump, a battery cold liquid plate, a third proportional valve, and a sixth waterway three-way joint. The first interface of the third proportional valve is connected to the second interface of the sixth waterway three-way joint, and its second interface is connected to the third interface of the second four-way valve; the first interface of the sixth waterway three-way joint is connected to the fourth interface of the first four-way valve, and its third interface is sequentially connected to the third interface of the third proportional valve through the battery water pump and the battery cold liquid plate.

[0015] Further, the motor water circuit includes a water tank, a motor, an on-vehicle charger, a fourth three-way valve, a low-pressure radiator, a low-pressure fan, and a seventh waterway three-way joint. The first interface of the fourth three-way valve is connected to the first interface of the seventh waterway three-way joint, and its second interface is sequentially connected to the third interface of the first four-way valve through the on-vehicle charger and the motor; the third interface of the fourth three-way valve is connected to one end of the low-pressure radiator; the second interface of the seventh waterway three-way joint is connected to the fourth interface of the second four-way valve, and its third interface is connected to the other end of the low-pressure radiator; the water tank is connected to the pipeline between the motor and the first four-way valve, and the low-pressure fan is arranged on the low-pressure radiator.

[0016] Further, R290 is used as the refrigerant in the refrigerant circuit.

[0017] An electric vehicle includes the above-mentioned secondary loop thermal management system.

[0018] The beneficial effects of the present invention are as follows:

[0019] (1) By setting up the refrigerant circuit, the passenger compartment water circuit, the battery water circuit, and the motor water circuit, the present invention forms a secondary loop. Compared with the existing secondary loop system, unnecessary components are reduced, the complexity and cost of the system are lowered, the heat management mode is enriched, and the heat exchange efficiency and system performance are improved.

[0020] (2) By setting up the bypass electronic expansion valve, the present invention uses it together with the main electronic expansion valve in an extremely low temperature (below -30°C) environment to further improve the heat exchange efficiency.

[0021] (3) By placing the PTC heater on the passenger compartment water circuit where the low-pressure water-cooled evaporator is located as the driving heat source, the present invention can not only effectively utilize the low-temperature environment to improve the heating efficiency, but also simplify the system structure, reduce the cost, and avoid the influence of the traditional heating method on the system performance.

[0022] (4) By using the stop valve to achieve the series connection of the warm air core body and the cold air core body, the present invention optimizes the heat exchange process, increases the heat exchange area, improves the heat exchange efficiency, reduces the energy loss, and at the same time ensures the comfort of the vehicle interior temperature and the response speed of the system.

[0023] (5) The present invention realizes the self-circulation of battery mixed water through the battery water circuit, enabling the battery to always maintain the operating temperature and quickly increasing the battery temperature in extremely low temperature environments, thereby improving the battery discharge efficiency and extending the service life of the battery.

[0024] (6) Through the setting of the motor water circuit, the present invention recovers the waste heat of the motor, realizes multiple waste heat recovery modes, and at the same time improves the heat exchange efficiency of the system in extremely low temperature environments, reduces the demand for external heat sources, and further reduces energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be further described below in conjunction with the drawings and embodiments.

[0026] Figure 1 It is a schematic structural diagram of the secondary circuit thermal management system in the present invention;

[0027] Figure 2 It is a flow path diagram of the refrigerant and coolant in the present invention in the passenger compartment refrigeration mode;

[0028] Figure 3 It is a flow path diagram of the refrigerant and coolant in the present invention in the passenger compartment + battery refrigeration mode;

[0029] Figure 4 It is a flow path diagram of the refrigerant and coolant in the present invention in the battery refrigeration mode;

[0030] Figure 5 It is a flow path diagram of the refrigerant and coolant in the present invention in the passenger compartment heating mode;

[0031] Figure 6 It is a flow path diagram of the refrigerant and coolant in the present invention in the passenger compartment + battery heating mode;

[0032] Figure 7 It is a flow path diagram of the refrigerant and coolant in the present invention in the battery heating mode;

[0033] Figure 8 It is a flow path diagram of the refrigerant and coolant in the present invention in the heating and dehumidifying mode 1;

[0034] Figure 9 It is a flow path diagram of the refrigerant and coolant in the present invention in the waste heat defrosting mode;

[0035] Figure 10 It is a flow path diagram of the refrigerant and coolant in the present invention in the waste heat recovery mode 1;

[0036] Figure 11 It is a flow path diagram of the refrigerant and coolant in the present invention in the double heating triangular cycle mode (extremely low temperature).

[0037] In the figure: 101, water-cooled evaporator; 102, gas-liquid separator; 103, compressor; 104, water-cooled condenser; 105, main electronic expansion valve; 106, auxiliary electronic expansion valve; 201, low-pressure side water pump; 202, PTC heater; 203, first three-way proportional valve; 204, second three-way proportional valve; 205, first three-way valve; 206, heater core; 207, second three-way valve; 208, first waterway three-way; 209, second waterway three-way; 210, stop valve; 211, third waterway three-way; 212, cold air core; 213, third three-way valve; 214, fourth waterway three-way; 215, fifth waterway three-way; 216, first four-way valve; 217, second four-way valve; 218, high-pressure side water pump; 301, battery water pump; 302, battery cold liquid plate; 303, third proportional valve; 304, sixth waterway three-way; 401, water tank; 402, motor; 403, on-board charger; 404, fourth three-way valve; 405, low-pressure radiator; 406, low-pressure fan; 407, seventh waterway three-way. Detailed implementation manners

[0038] Now, the present invention will be further described in conjunction with the accompanying drawings and preferred embodiments. These drawings are all simplified schematic diagrams, only illustrating the basic structure of the present invention in a schematic manner, so they only show the components related to the present invention.

[0039] Embodiment 1:

[0040] As Figure 1 shown, a secondary loop thermal management system includes a refrigerant loop, a passenger compartment water loop, a battery water loop, and a motor water loop. The refrigerant loop includes a water-cooled evaporator 101 and a water-cooled condenser 104; the passenger compartment water loop includes a first four-way valve 216 and a second four-way valve 217. The first interface of the first four-way valve 216 is connected to the first end of the water-cooled evaporator 101, and its second interface is connected to the third end of the water-cooled condenser 104; the first interface of the second four-way valve 217 is connected to the fourth end of the water-cooled condenser 104, and its second interface is connected to the second end of the water-cooled evaporator 101 for heat exchange in the passenger compartment; the battery water loop is respectively connected to the fourth interface of the first four-way valve 216 and the third interface of the second four-way valve 217 for heat exchange with the battery; the motor water loop is respectively connected to the third interface of the first four-way valve 216 and the fourth interface of the second four-way valve 217 for heat exchange with the motor. Specifically, the refrigerant in the refrigerant loop is R290.

[0041] Through the settings of the refrigerant loop, the passenger compartment water loop, the battery water loop, and the motor water loop, a secondary loop is formed. Compared with the existing secondary loop system, unnecessary components are reduced, the complexity and cost of the system are reduced, the heat management mode is enriched, and the heat exchange efficiency and system performance are improved.

[0042] As Figure 1 shown, the refrigerant circuit further includes a gas-liquid separator 102, a compressor 103, and a main electronic expansion valve 105. The third end of the water-cooled evaporator 101 is sequentially connected to the first end of the water-cooled condenser 104 through the gas-liquid separator 102 and the compressor 103, and its fourth end is connected to the second end of the water-cooled condenser 104 through the main electronic expansion valve 105.

[0043] As Figure 1 shown, the refrigerant circuit further includes a bypass electronic expansion valve 106. The third end of the water-cooled evaporator 101 is connected to the first end of the water-cooled condenser 104 through the bypass electronic expansion valve 106. Through the setting of the bypass electronic expansion valve 106, it is used simultaneously with the main electronic expansion valve 105 in an extremely low temperature (lower than -30 °C) environment, further improving the heat exchange efficiency.

[0044] In the refrigerant circuit, the low-temperature and low-pressure R290 working medium gas is compressed into a high-temperature and high-pressure gas by the compressor 103 and is divided into two paths. One path leads to the water-cooled condenser 104 for heating supply, and the other path directly connects the exhaust pipe and the suction pipe of the compressor 103 through the bypass circuit where the bypass electronic expansion valve 106 is located to realize the electric heating of the compressor 103.

[0045] As Figure 1As shown in the figure, the passenger compartment water circuit further includes a low-pressure side water pump 201, a PTC heater 202, a first three-way proportional valve 203, a second three-way proportional valve 204, a first three-way valve 205, a heater core 206, a second three-way valve 207, a first waterway three-way 208, a second waterway three-way 209, a third waterway three-way 211, a cold air core 212, a third three-way valve 213, a fourth waterway three-way 214, a fifth waterway three-way 215, and a high-pressure side water pump 218. The first interface of the first three-way proportional valve 203 is connected to the first end of the water-cooled evaporator 101 through the PTC heater 202, and its second interface is connected to the first interface of the first four-way valve 216. The first interface of the second three-way proportional valve 204 is connected to the third end of the water-cooled condenser 104, and its second interface is connected to the second interface of the first four-way valve 216. The first interface of the fifth waterway three-way 215 is connected to the second end of the water-cooled evaporator 101 through the low-pressure side water pump 201, and its second interface is connected to the second interface of the second four-way valve 217. The first interface of the first waterway three-way 208 is connected to the fourth end of the water-cooled condenser 104 through the high-pressure side water pump 218, and its second interface is connected to the first interface of the second four-way valve 217. The first interface of the first three-way valve 205 is connected to the third interface of the second three-way proportional valve 204, and its second interface is connected to the first interface of the second waterway three-way 209. The third interface of the first three-way valve 205 is connected to the third interface of the third waterway three-way 211. One end of the heater core 206 is connected to the second interface of the second waterway three-way 209, and the other end is connected to the first interface of the second three-way valve 207. The second interface of the second three-way valve 207 is connected to the third interface of the first waterway three-way 208, and its third interface is connected to the third interface of the fourth waterway three-way 214. The first interface of the third waterway three-way 211 is connected to the third interface of the first three-way proportional valve 203, and its second interface is connected to one end of the cold air core 212. The first interface of the third three-way valve 213 is connected to the other end of the cold air core 212, and its second interface is connected to the first interface of the fourth waterway three-way 214. The second interface of the fourth waterway three-way 214 is connected to the third interface of the fifth waterway three-way 215. Placing the PTC heater 202 on the passenger compartment water circuit where the low-pressure water-cooled evaporator 101 is located as a driving heat source to indirectly provide heat can not only effectively utilize the low-temperature environment to improve the heating efficiency, but also simplify the system structure, reduce costs, and avoid the impact of traditional heating methods on the system performance.

[0046] As Figure 1As shown, the passenger compartment water circuit further includes a stop valve 210. The first interface of the stop valve 210 is connected to the third interface of the second waterway tee 209, and its second interface is connected to the third interface of the third three-way valve 213. The series connection of the warm air core 206 and the cold air core 212 is achieved through the stop valve 210, optimizing the heat exchange process, increasing the heat exchange area, improving the heat exchange efficiency, reducing energy loss, and at the same time ensuring the comfort of the vehicle interior temperature and the response speed of the system.

[0047] As Figure 1 shown, the battery water circuit includes a battery water pump 301, a battery cold liquid plate 302, a third proportional valve 303, and a sixth waterway tee 304. The first interface of the third proportional valve 303 is connected to the second interface of the sixth waterway tee 304, and its second interface is connected to the third interface of the second four-way valve 217; the first interface of the sixth waterway tee 304 is connected to the fourth interface of the first four-way valve 216, and its third interface is sequentially connected to the third interface of the third proportional valve 303 through the battery water pump 301 and the battery cold liquid plate 302. The battery water circuit realizes the self-circulation of battery mixed water, enabling the battery to always maintain its operating temperature and quickly increasing the battery temperature in extremely low temperature environments, thereby improving the battery's discharge efficiency and extending the battery's service life. During operation, cold water flows out from the fourth interface of the first four-way valve 216, and hot water flows out from the third interface of the third proportional valve 303. The cold water and hot water are mixed at the sixth waterway tee 304 and then flow out from the third interface of the sixth waterway tee 304 for heat exchange with the battery.

[0048] As Figure 1 shown, the motor water circuit includes a water tank 401, a motor 402, an on-vehicle charger 403, a fourth three-way valve 404, a low-pressure radiator 405, a low-pressure fan 406, and a seventh waterway tee 407. The first interface of the fourth three-way valve 404 is connected to the first interface of the seventh waterway tee 407, and its second interface is sequentially connected to the third interface of the first four-way valve 216 through the on-vehicle charger 403 and the motor 402; the third interface of the fourth three-way valve 404 is connected to one end of the low-pressure radiator 405; the second interface of the seventh waterway tee 407 is connected to the fourth interface of the second four-way valve 217, and its third interface is connected to the other end of the low-pressure radiator 405; the water tank 401 is connected to the pipeline between the motor 402 and the first four-way valve 216, and the low-pressure fan 406 is arranged on the low-pressure radiator 405. The setting of the motor water circuit recovers the waste heat of the motor, realizes multiple waste heat recovery modes, and at the same time improves the heat exchange efficiency of the system in extremely low temperature environments, reduces the demand for external heat sources, and further reduces energy consumption.

[0049] Specifically, the waste heat of the motor is transferred to the battery through the motor water circuit and the battery water circuit, thereby heating the battery or maintaining its operating temperature; the waste heat of the motor is transferred to the coolant in the water circuit where the low-temperature water-cooled evaporator 101 is located through a heat exchanger. After the coolant is heated, the low-pressure side pressure of the water circuit where the low-temperature water-cooled evaporator 101 is located can be increased, and the higher low-pressure can improve the heat exchange efficiency of the entire system, thereby helping to improve the circulation efficiency of the R290 refrigerant in the water circuit where the low-temperature water-cooled evaporator 101 is located.

[0050] The basic heat management modes in the secondary circuit heat management system include passenger compartment refrigeration mode, battery refrigeration mode, passenger compartment + battery refrigeration mode, passenger compartment heating mode, passenger compartment heating mode (extremely low temperature), battery heating mode, passenger compartment + battery heating mode, heating (cooling) dehumidification mode 1, heating (cooling) dehumidification mode 2, heating / waste heat defrosting mode (preheating / idle), heating / waste heat defrosting mode (driving), ventilation defrosting mode, waste heat recovery mode 1, waste heat recovery mode 2, and dual heating triangular cycle mode (extremely low temperature).

[0051] As Figure 2 shown, the circulation paths of the refrigerant and the coolant in the passenger compartment refrigeration mode are as follows:

[0052] Refrigerant circuit: water-cooled evaporator 101 → gas-liquid separator 102 → compressor 103 → water-cooled condenser 104 → main electronic expansion valve 105 → water-cooled evaporator 101.

[0053] Water circuit: water-cooled evaporator 101 → PTC heater 202 → first three-way proportional valve 203 → third waterway three-way 211 → cold air core 212 → third three-way valve 213 → stop valve 210 → second waterway three-way 209 → warm air core 206 → second three-way valve 207 → fourth waterway three-way 214 → fifth waterway three-way 215 → low-pressure side water pump 201 → water-cooled evaporator 101; water-cooled condenser 104 → second three-way proportional valve 204 → first four-way valve 216 → motor 402 → on-vehicle charger 403 → fourth three-way valve 404 → low-pressure radiator 405 → seventh waterway three-way 407 → second four-way valve 217 → first waterway three-way 208 → high-pressure side water pump 218 → water-cooled condenser 104.

[0054] As Figure 3 shown, the circulation paths of the refrigerant and the coolant in the passenger compartment + battery refrigeration mode are as follows:

[0055] The refrigerant circuit is the same as the refrigerant circuit in the passenger compartment refrigeration mode.

[0056] Water circuit: Water-cooled evaporator 101 → PTC heater 202 → First three-way proportional valve 203 → Branch ① and Branch ② → Fifth water-way three-way 215 → Low-pressure side water pump 201 → Water-cooled evaporator 101; among them, Branch ① is: Third water-way three-way 211 → Cold air core 212 → Third three-way valve 213 → Stop valve 210 → Second water-way three-way 209 → Warm air core 206 → Second three-way valve 207 → Fourth water-way three-way 214, and Branch ② is: First four-way valve 216 → Sixth water-way three-way 304 → Battery water pump 301 → Battery cold liquid plate 302 → Third proportional valve 303 → Second four-way valve 217, where part of the coolant passing through the third proportional valve 303 enters the sixth water-way three-way 304 for mixing; Water-cooled condenser 104 → Second three-way proportional valve 204 → First four-way valve 216 → Motor 402 → On-board charger 403 → Fourth three-way valve 404 → Low-pressure radiator 405 → Seventh water-way three-way 407 → Second four-way valve 217 → First water-way three-way 208 → High-pressure side water pump 218 → Water-cooled condenser 104.

[0057] As Figure 4 shown, the circulation paths of the refrigerant and the coolant in the battery cooling mode are as follows:

[0058] The refrigerant circuit is the same as the refrigerant circuit in the passenger compartment cooling mode.

[0059] Water circuit: Water-cooled evaporator 101 → PTC heater 202 → First three-way proportional valve 203 → First four-way valve 216 → Sixth water-way three-way 304 → Battery water pump 301 → Battery cold liquid plate 302 → Third proportional valve 303 → Second four-way valve 217 → Fifth water-way three-way 215 → Low-pressure side water pump 201 → Water-cooled evaporator 101, where part of the coolant passing through the third proportional valve 303 enters the sixth water-way three-way 304 for mixing; Water-cooled condenser 104 → Second three-way proportional valve 204 → First four-way valve 216 → Motor 402 → On-board charger 403 → Fourth three-way valve 404 → Low-pressure radiator 405 → Seventh water-way three-way 407 → Second four-way valve 217 → First water-way three-way 208 → High-pressure side water pump 218 → Water-cooled condenser 104.

[0060] As Figure 5 shown, the circulation paths of the refrigerant and the coolant in the passenger compartment heating mode are as follows:

[0061] The refrigerant circuit is the same as the refrigerant circuit in the passenger compartment cooling mode.

[0062] Water circuit: Water-cooled evaporator 101 → PTC heater 202 → First three-way proportional valve 203 → First four-way valve 216 → Motor 402 → On-board charger 403 → Fourth three-way valve 404 → Low-pressure radiator 405 → Seventh water-way three-way 407 → Second four-way valve 217 → Fifth water-way three-way 215 → Low-pressure side water pump 201 → Water-cooled evaporator 101; Water-cooled condenser 104 → Second three-way proportional valve 204 → First three-way valve 205 → Third water-way three-way 211 → Cold air core 212 → Third three-way valve 213 → Cut-off valve 210 → Second water-way three-way 209 → Warm air core 206 → Second three-way valve 207 → First water-way three-way 208 → High-pressure side water pump 218 → Water-cooled condenser 104.

[0063] As Figure 6 shown, the circulation paths of the refrigerant and the coolant in the passenger compartment + battery heating mode are as follows:

[0064] The refrigerant circuit is the same as the refrigerant circuit in the passenger compartment cooling mode.

[0065] Water circuit: Water-cooled evaporator 101 → PTC heater 202 → First three-way proportional valve 203 → First four-way valve 216 → Motor 402 → On-board charger 403 → Fourth three-way valve 404 → Low-pressure radiator 405 → Seventh water-way three-way 407 → Second four-way valve 217 → Fifth water-way three-way 215 → Low-pressure side water pump 201 → Water-cooled evaporator 101; Water-cooled condenser 104 → Second three-way proportional valve 204 → Branch ① and Branch ② → First water-way three-way 208 → High-pressure side water pump 218 → Water-cooled condenser 104; where Branch ① is: First three-way valve 205 → Third water-way three-way 211 → Cold air core 212 → Third three-way valve 213 → Cut-off valve 210 → Second water-way three-way 209 → Warm air core 206 → Second three-way valve 207, and Branch ② is: First four-way valve 216 → Sixth water-way three-way 304 → Battery water pump 301 → Battery cold liquid plate 302 → Third proportional valve 303 → Second four-way valve 217, and part of the coolant passing through the third proportional valve 303 enters the sixth water-way three-way 304 for mixing.

[0066] As Figure 7 shown, the circulation paths of the refrigerant and the coolant in the battery heating mode are as follows:

[0067] The refrigerant circuit is the same as the refrigerant circuit in the passenger compartment cooling mode.

[0068] Water circuit: Water-cooled evaporator 101 → PTC heater 202 → First three-way proportional valve 203 → First four-way valve 216 → Motor 402 → On-board charger 403 → Fourth three-way valve 404 → Low-pressure radiator 405 → Seventh water-way three-way 407 → Second four-way valve 217 → Fifth water-way three-way 215 → Low-pressure side water pump 201 → Water-cooled evaporator 101; Water-cooled condenser 104 → Second three-way proportional valve 204 → First four-way valve 216 → Sixth water-way three-way 304 → Battery water pump 301 → Battery cold liquid plate 302 → Third proportional valve 303 → Second four-way valve 217 → First water-way three-way 208 → High-pressure side water pump 218 → Water-cooled condenser 104, where part of the coolant passing through the third proportional valve 303 enters the sixth water-way three-way 304 for mixing.

[0069] As Figure 8 shown, the flow paths of the refrigerant and the coolant in heating and dehumidifying mode 1 are as follows:

[0070] The refrigerant circuit is the same as the refrigerant circuit in the passenger compartment cooling mode.

[0071] Water circuit: Water-cooled evaporator 101 → PTC heater 202 → First three-way proportional valve 203 → Third water-way three-way 211 → Cold air core 212 → Third three-way valve 213 → Fourth water-way three-way 214 → Fifth water-way three-way 215 → Low-pressure side water pump 201 → Water-cooled evaporator 101; Water-cooled condenser 104 → Second three-way proportional valve 204 → First three-way valve 205 → Second water-way three-way 209 → Warm air core 206 → Second three-way valve 207 → First water-way three-way 208 → High-pressure side water pump 218 → Water-cooled condenser 104.

[0072] As Figure 9 shown, the flow paths of the refrigerant and the coolant in the waste heat defrosting mode are as follows:

[0073] Water circuit: Water-cooled condenser 104 → Second three-way proportional valve 204 → First four-way valve 216 → Motor 402 → On-board charger 403 → Fourth three-way valve 404 → Low-pressure radiator 405 → Seventh water-way three-way 407 → Second four-way valve 217 → First water-way three-way 208 → High-pressure side water pump 218 → Water-cooled condenser 104.

[0074] As Figure 10 shown, the flow paths of the refrigerant and the coolant in waste heat recovery mode 1 are as follows:

[0075] Water circuit: Water-cooled evaporator 101 → PTC heater 202 → First three-way proportional valve 203 → First four-way valve 216 → Motor 402 → On-board charger 403 → Fourth three-way valve 404 → Seventh water-way three-way 407 → Second four-way valve 217 → Fifth water-way three-way 215 → Low-pressure side water pump 201 → Water-cooled evaporator 101; Water-cooled condenser 104 → Second three-way proportional valve 204 → First three-way valve 205 → Third water-way three-way 211 → Cold air core 212 → Third three-way valve 213 → Stop valve 210 → Second water-way three-way 209 → Warm air core 206 → Second three-way valve 207 → First water-way three-way 208 → High-pressure side water pump 218 → Water-cooled condenser 104.

[0076] As Figure 11 shown, the flow paths of the refrigerant and the coolant in the dual-heating triangular circulation mode (extremely low temperature) are as follows:

[0077] Refrigerant circuit: Water-cooled evaporator 101 → Gas-liquid separator 102 → Compressor 103 → Branch ① and Branch ②; among them, Branch ① is: Water-cooled condenser 104 → Main electronic expansion valve 105 → Water-cooled evaporator 101, and Branch ② is: Auxiliary electronic expansion valve 106 → Gas-liquid separator 102 → Compressor 103.

[0078] Water circuit: Water-cooled evaporator 101 → PTC heater 202 → First three-way proportional valve 203 → First four-way valve 216 → Motor 402 → On-board charger 403 → Fourth three-way valve 404 → Low-pressure radiator 405 → Seventh water-way three-way 407 → Second four-way valve 217 → Fifth water-way three-way 215 → Low-pressure side water pump 201 → Water-cooled evaporator 101; Water-cooled condenser 104 → Second three-way proportional valve 204 → Branch ① and Branch ② → First water-way three-way 208 → High-pressure side water pump 218 → Water-cooled condenser 104; among them, Branch ① is: First three-way valve 205 → Third water-way three-way 211 → Cold air core 212 → Third three-way valve 213 → Stop valve 210 → Second water-way three-way 209 → Warm air core 206 → Second three-way valve 207, and Branch ② is: First four-way valve 216 → Sixth water-way three-way 304 → Battery water pump 301 → Battery cold liquid plate 302 → Third proportional valve 303 → Second four-way valve 217, and part of the coolant passing through the third proportional valve 303 enters the sixth water-way three-way 304 for mixing.

[0079] Embodiment 2:

[0080] An electric vehicle includes the secondary circuit thermal management system described in Embodiment 1.

[0081] The above embodiments are only used to illustrate the technical concept and features of the present invention. The purpose is to enable those skilled in the art to understand the content of the present invention and implement it, and it cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A secondary circuit thermal management system, comprising a refrigerant circuit, the refrigerant circuit comprising a water-cooled evaporator (101) and a water-cooled condenser (104), characterized in that: Also includes A passenger compartment water circuit, used for heat exchange in the passenger compartment; The passenger compartment water circuit comprises a first four-way valve (216) and a second four-way valve (217); a first interface of the first four-way valve (216) is connected to a first end of a water-cooled evaporator (101), and a second interface thereof is connected to a third end of a water-cooled condenser (104); a first interface of the second four-way valve (217) is connected to a fourth end of the water-cooled condenser (104), and a second interface thereof is connected to a second end of the water-cooled evaporator (101); A battery water circuit, connected to the fourth interface of the first four-way valve (216) and the third interface of the second four-way valve (217), respectively, for heat exchange of the battery; and a motor water circuit, respectively connected to the third interface of the first four-way valve (216) and the fourth interface of the second four-way valve (217), for heat exchange of the motor; The passenger compartment water circuit further comprises a low-pressure side water pump (201), a PTC heater (202), a first three-way proportional valve (203), a second three-way proportional valve (204), a first three-way valve (205), a warm air core (206), a second three-way valve (207), a first water channel three-way (208), a second water channel three-way (209), a third water channel three-way (211), a cold air core (212), a third three-way valve (213), a fourth water channel three-way (214), a fifth water channel three-way (215) and a high-pressure side water pump (218). The first interface of the first three-way proportional valve (203) is connected to the PTC heater ( The first interface of the water-cooled evaporator (101) is connected to the first end of the water-cooled evaporator (101), and its second interface is connected to the first interface of the first four-way valve (216); the first interface of the second three-way proportional valve (204) is connected to the third end of the water-cooled condenser (104), and its second interface is connected to the second interface of the first four-way valve (216); the first interface of the fifth water channel three-way (215) is connected to the second end of the water-cooled evaporator (101) through the low-pressure side water pump (201), and its second interface is connected to the second interface of the second four-way valve (217); the first interface of the first water channel three-way (208) is connected to the high-pressure side water pump (218) through the high-pressure side water pump (218) The fourth end of the water-cooled condenser (104) is connected, and its second interface is connected to the first interface of the second four-way valve (217); the first interface of the first three-way valve (205) is connected to the third interface of the second three-way proportional valve (204), and its second interface is connected to the first interface of the second water circuit three-way (209); the third interface of the first three-way valve (205) is connected to the third interface of the third water circuit three-way (211); one end of the warm air core (206) is connected to the second interface of the second water circuit three-way (209), and the other end of the warm air core (206) is connected to the first interface of the second three-way valve (207); the second three-way valve (20 The second interface of the water circuit tee (207) is connected to the third interface of the first water circuit tee (208), and the third interface thereof is connected to the third interface of the fourth water circuit tee (214); the first interface of the third water circuit tee (211) is connected to the third interface of the first three-way proportional valve (203), and the second interface thereof is connected to one end of the cold air core (212); the first interface of the third three-way valve (213) is connected to the other end of the cold air core (212), and the second interface thereof is connected to the first interface of the fourth water circuit tee (214); the second interface of the fourth water circuit tee (214) is connected to the third interface of the fifth water circuit tee (215); The passenger compartment water circuit also includes a stop valve (210), a first interface of the stop valve (210) being connected to a third interface of the second water circuit tee (209), and a second interface of the stop valve (210) being connected to a third interface of a third three-way valve (213).

2. The secondary circuit thermal management system according to claim 1, characterized in that: The refrigerant circuit further comprises a gas-liquid separator (102), a compressor (103) and a main electronic expansion valve (105); the third end of the water-cooled evaporator (101) is connected to the first end of the water-cooled condenser (104) via the gas-liquid separator (102) and the compressor (103) in sequence, and the fourth end of the water-cooled evaporator is connected to the second end of the water-cooled condenser (104) via the main electronic expansion valve (105).

3. The secondary circuit thermal management system according to claim 2, characterized in that: The refrigerant circuit further comprises a bypass electronic expansion valve (106), and the third end of the water-cooled evaporator (101) is connected to the first end of the water-cooled condenser (104) via the bypass electronic expansion valve (106).

4. The secondary circuit thermal management system according to claim 1, characterized in that: The battery water circuit comprises a battery water pump (301), a battery cold liquid plate (302), a third proportional valve (303) and a sixth water channel tee (304); a first interface of the third proportional valve (303) is connected to a second interface of the sixth water channel tee (304), and a second interface thereof is connected to a third interface of the second four-way valve (217); a first interface of the sixth water channel tee (304) is connected to a fourth interface of the first four-way valve (216), and a third interface thereof is connected to a third interface of the third proportional valve (303) via the battery water pump (301) and the battery cold liquid plate (302) in sequence.

5. The secondary circuit thermal management system according to claim 1, characterized in that: The motor water circuit comprises a water tank (401), a motor (402), an on-board charger (403), a fourth three-way valve (404), a low-pressure radiator (405), a low-pressure fan (406) and a seventh water three-way valve (407); a first interface of the fourth three-way valve (404) is connected to a first interface of the seventh water three-way valve (407), and a second interface thereof is connected to a first interface of the first four-way valve (216) via the on-board charger (403) and the motor (402) in sequence. The invention relates to a water tank (401) and a water circuit comprising: a first water circuit (402) and a second water circuit (403) connected to the first water circuit (404); a third water circuit (404) connected to one end of a low-pressure radiator (405); a second water circuit (407) connected to the fourth water circuit (404) of the second four-way valve (217); and a third water circuit (407) connected to the other end of the low-pressure radiator (405); the water tank (401) is connected to the pipeline between the motor (402) and the first four-way valve (216); and the low-pressure fan (406) is arranged on the low-pressure radiator (405).

6. The secondary circuit thermal management system according to claim 1, characterized in that: The refrigerant in the refrigerant circuit is R290.

7. An electric vehicle, characterized in that: It includes the secondary circuit thermal management system described in any one of claims 1-6.

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