Waste heat recovery system of pure electric loader

Abstract

The invention discloses a waste heat recovery system of a pure electric loader, and belongs to the technical field of electric loaders. A pure electric loader waste heat recovery system comprises a motor cooling module and a first heat exchanger. The motor cooling module is connected with the first heat exchanger; the battery cooling module is connected with the first heat exchanger; the hydraulic oil cooling module is connected with the first heat exchanger; the waste heat recovery module is connected with the first heat exchanger and used for converting heat into electric energy and storing the electric energy as a standby power supply; the phase change heat storage module is connected with the battery cooling module; through the multi-loop integrated design of the first heat exchanger, the waste heat utilization rate of hydraulic oil is obviously increased, and the endurance mileage is effectively prolonged; meanwhile, latent heat of vaporization of the phase change heat storage medium is utilized for refrigeration in summer, and energy consumption is obviously reduced; in winter, heating of the cab is achieved through waste heat of the radiator, electric heating is completely replaced, and the endurance mileage is further prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of electric loaders, and in particular to a waste heat recovery system for a pure electric loader. Background Art

[0002] With the continuous advancement of new energy, the main trend of loaders in the Chinese market is to gradually achieve electrification.

[0003] Currently, most loaders release a large amount of heat when charging. Although electric loaders are equipped with heat dissipation devices, this energy is not recycled during actual use. In addition, the loader needs to consume a large amount of energy to maintain the discharge efficiency of the battery in cold working conditions, which limits the cruising range of the electric loader. Summary of the Invention

[0004] The purpose of the present invention is to solve the problems raised in the above background technology and to propose a pure electric loader waste heat recovery system.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: A waste heat recovery system for a pure electric loader, comprising: A motor cooling module and a first heat exchanger; the motor cooling module is connected to the first heat exchanger; the motor cooling module is used to cool the motor and start waste heat recovery when the temperature reaches a critical value; A battery cooling module, connected to the first heat exchanger, is used to cool and heat the battery, maintain the battery's operating temperature, and simultaneously perform waste heat recovery and secondary heat recovery; a hydraulic oil cooling module connected to the first heat exchanger, the hydraulic oil cooling module being used to control the circulation of the hydraulic oil and to perform heat exchange through the first heat exchanger, thereby cooling the hydraulic oil and recovering waste heat; a waste heat recovery module, connected to the first heat exchanger, for converting heat into electrical energy and storing it as a backup power source; The phase change heat storage module is connected to the battery cooling module and is used for secondary heat recovery of the coolant after waste heat recovery.

[0006] Preferably, the motor cooling module includes a motor, a first controller, a flow pump, a first temperature sensor and a first solenoid valve; the motor is electrically connected to the first controller, and the flow pump is connected to the first controller for controlling the coolant flow; the first temperature sensor is used to monitor the coolant temperature, and the first solenoid valve is connected to the first heat exchanger. When the first temperature sensor detects that the temperature reaches a critical value, the first solenoid valve is connected to the first heat exchanger to start waste heat recovery.

[0007] Preferably, the battery cooling module includes a heater, a battery pack, a second temperature sensor, a second solenoid valve, an expansion water tank and a second flow pump; the heater is used to heat the battery pack, and the expansion water tank forms a coolant circulation loop with the battery pack through the second flow pump; the second temperature sensor is used to monitor the battery pack temperature, and when the temperature reaches a critical value, the second solenoid valve is connected to the first heat exchanger to cool it down; when the temperature of the coolant after waste heat recovery is greater than the critical value, the battery cooling module is connected to the phase change heat storage module to perform secondary heat recovery.

[0008] Preferably, the hydraulic oil cooling module includes a hydraulic oil tank, a third temperature sensor, a third solenoid valve and a first circulation pump; the first circulation pump drives the hydraulic oil to circulate in the hydraulic oil tank, and the third temperature sensor is used to monitor the temperature of the hydraulic oil. When the temperature reaches a critical value, the third solenoid valve is connected to the first heat exchanger, and the hydraulic oil is subjected to heat exchange cooling and waste heat recovery through the first heat exchanger.

[0009] Preferably, the waste heat recovery module includes a scroll expander, a generator, a battery, a second controller, a condenser, a working fluid tank and a working fluid pump; the working fluid in the working fluid tank is pressurized by the working fluid pump and enters the first heat exchanger to absorb heat and vaporize, and the vaporized working fluid steam drives the scroll expander to drive the generator to generate electricity, and the electrical energy is stored in the battery; the expanded working fluid steam is condensed by the condenser and then flows back to the working fluid tank, and the second controller independently controls the circulation of the waste heat recovery module.

[0010] Preferably, the phase change heat storage module includes a fourth solenoid valve, a fourth temperature sensor, a phase change heat storage mechanism, a second heat exchanger, a second circulation pump, a refrigerator, a radiator, a fifth solenoid valve, a sixth solenoid valve and a seventh solenoid valve; the fourth temperature sensor monitors the coolant temperature of the battery cooling module. When the temperature reaches a critical value, the fourth solenoid valve is connected to the phase change heat storage mechanism, and the coolant exchanges heat with the medium in the phase change heat storage mechanism through the second heat exchanger. After the medium is vaporized, it is driven by the second circulation pump and switched to the refrigerator or radiator through the fifth solenoid valve.

[0011] Compared with the prior art, the present invention provides a waste heat recovery system for a pure electric loader, which has the following beneficial effects: The parts not involved in this device are the same as the existing technology or can be implemented by existing technology. The present invention significantly improves the utilization rate of the waste heat of the hydraulic oil through the multi-circuit integrated design of the first heat exchanger, effectively extending the cruising range; at the same time, the latent heat of vaporization of the phase change heat storage medium is used for cooling in summer, which significantly reduces energy consumption; in winter, the cab is heated by the waste heat of the radiator, completely replacing electric heating, further extending the cruising range. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1This is a structural schematic diagram of a pure electric loader waste heat recovery system proposed by the present invention.

[0013] In the figure: 1. motor; 2. first controller; 3. first flow pump; 4. first temperature sensor; 5. first solenoid valve; 6. first heat exchanger; 21. hydraulic oil tank; 22. third temperature sensor; 23. third solenoid valve; 24. first circulation pump; 31. heater; 32. battery pack; 33. second temperature sensor; 34. second solenoid valve; 35. expansion tank; 36. second flow pump; 41. fifth solenoid valve; 42. refrigerator; 43. sixth solenoid valve; 44. radiator; 45. seventh solenoid valve; 46. second heat exchanger; 47. second circulation pump; 48. phase change heat storage mechanism; 49. fourth temperature sensor; 50. fourth solenoid valve; 61. second controller; 62. battery; 63. generator; 64. scroll expander; 65. condenser; 66. working fluid tank; 67. working fluid pump. DETAILED DESCRIPTION

[0014] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0015] Reference Figure 1 , a pure electric loader waste heat recovery system, comprising: Motor cooling module and first heat exchanger 6; the motor cooling module is connected to the first heat exchanger 6; the motor cooling module is used to cool the motor and start waste heat recovery when the temperature reaches a critical value; A battery cooling module is connected to the first heat exchanger 6 and is used to cool and heat the battery, maintain the operating temperature of the battery, and perform waste heat recovery and secondary heat recovery; A hydraulic oil cooling module is connected to the first heat exchanger 6. The hydraulic oil cooling module is used to control the circulation of the hydraulic oil and perform heat exchange through the first heat exchanger 6 to cool the hydraulic oil and recover waste heat; A waste heat recovery module, connected to the first heat exchanger 6, is used to convert heat into electrical energy and store it as a backup power source; The phase change heat storage module is connected to the battery cooling module and is used for secondary heat recovery of the coolant after waste heat recovery.

[0016] The motor cooling module includes a motor 1, a first controller 2, a flow pump 3, a first temperature sensor 4 and a first solenoid valve 5; the motor 1 is electrically connected to the first controller 2, and the flow pump 3 is connected to the first controller 2 for controlling the coolant flow; the first temperature sensor 4 is used to monitor the coolant temperature, and the first solenoid valve 5 is connected to the first heat exchanger 6. When the first temperature sensor 4 detects that the temperature reaches a critical value, the first solenoid valve 5 is connected to the first heat exchanger 6 to start waste heat recovery.

[0017] Reference Figure 1 When in use, when the first temperature sensor 4 detects that the motor coolant temperature exceeds the critical value of 65°C, the first controller 2 opens the first solenoid valve 5, and the coolant enters the first heat exchanger 6 to exchange heat with the working fluid of the waste heat recovery module.

[0018] The low-boiling-point working medium in the working medium tank 66 , such as R134a, is pressurized by the working medium pump 67 and enters the first heat exchanger 6 , where it absorbs heat from the motor coolant and vaporizes into high-temperature and high-pressure steam.

[0019] The battery cooling module includes a heater 31, a battery pack 32, a second temperature sensor 33, a second solenoid valve 34, an expansion water tank 35 and a second flow pump 36; the heater 31 is used to heat the battery pack 32, and the expansion water tank 35 forms a coolant circulation loop with the battery pack 32 through the second flow pump 36; the second temperature sensor 33 is used to monitor the temperature of the battery pack 32. When the temperature reaches a critical value, the second solenoid valve 34 is connected to the first heat exchanger 6 to cool it down; when the temperature of the coolant after waste heat recovery is greater than the critical value, the battery cooling module is connected to the phase change heat storage module for secondary heat recovery.

[0020] Reference Figure 1 , in specific implementation: When the working condition is high temperature, when the second temperature sensor 33 detects that the temperature of the battery pack 32 exceeds the critical value of 40°C, the second solenoid valve 34 opens, and the battery coolant exchanges heat with the waste heat of the hydraulic oil through the first heat exchanger 6 to cool down.

[0021] When the operating condition is low temperature, when the battery pack temperature is lower than the critical value of 10°C, the heater 31 starts to preheat the battery pack. At the same time, when the fourth temperature sensor 49 detects that the phase change heat storage module coolant temperature is greater than 25°C, the fourth solenoid valve 50 is turned on and the heat of the heat storage medium is transferred to the battery coolant circuit through the second heat exchanger 46.

[0022] The hydraulic oil cooling module includes a hydraulic oil tank 21, a third temperature sensor 22, a third solenoid valve 23 and a first circulation pump 24; the first circulation pump 24 drives the hydraulic oil to circulate in the hydraulic oil tank 21, and the third temperature sensor 22 is used to monitor the temperature of the hydraulic oil. When the temperature reaches a critical value, the third solenoid valve 23 is connected to the first heat exchanger 6, and the hydraulic oil is subjected to heat exchange cooling and waste heat recovery through the first heat exchanger 6.

[0023] During specific implementation, when the third temperature sensor 22 detects that the hydraulic oil temperature exceeds the critical value of 70°C, the hydraulic oil cooling module controller opens the third solenoid valve 23, and the hydraulic oil enters the first heat exchanger 6 through the first circulation pump 24, and performs heat exchange with the motor coolant and the working fluid synchronously; after the hydraulic oil temperature drops, it flows back to the hydraulic oil tank 21, and the working fluid steam drives the vortex expander 64 to drive the generator 63 to generate electricity, and the electrical energy is stored in the battery 62.

[0024] The waste heat recovery module includes a scroll expander 64, a generator 63, a battery 62, a second controller 61, a condenser 65, a working fluid tank 66 and a working fluid pump 67; the working fluid in the working fluid tank 66 is pressurized by the working fluid pump 67 and enters the first heat exchanger 6 to absorb heat and vaporize. The vaporized working fluid steam drives the scroll expander 64 to drive the generator 63 to generate electricity, and the electrical energy is stored in the battery 62; the expanded working fluid steam is condensed by the condenser 65 and then flows back to the working fluid tank 66, and the second controller 61 independently controls the circulation of the waste heat recovery module.

[0025] The second controller 61 ensures maximum waste heat recovery efficiency by dynamically adjusting the speed of the working fluid pump 67 and the opening of the air inlet valve of the scroll expander 64 according to the power of the battery 62 and the temperature and pressure parameters of the working fluid.

[0026] The condensed working fluid flows back to the working fluid tank 66, completing a closed cycle. The entire process does not require external energy input.

[0027] The phase change heat storage module includes a fourth solenoid valve 50, a fourth temperature sensor 49, a phase change heat storage mechanism 48, a second heat exchanger 46, a second circulation pump 47, a refrigerator 42, a radiator 44, a fifth solenoid valve 41, a sixth solenoid valve 43 and a seventh solenoid valve 45; the fourth temperature sensor 49 monitors the coolant temperature of the battery cooling module. When the temperature reaches a critical value, the fourth solenoid valve 50 is connected to the phase change heat storage mechanism 48, and the coolant exchanges heat with the medium in the phase change heat storage mechanism 48 through the second heat exchanger 46. After the medium is vaporized, it is driven by the second circulation pump 47 and switched to the refrigerator 42 or the radiator 44 through the fifth solenoid valve 41; in summer, the medium is liquefied by the refrigerator 42 to achieve cab cooling, and in winter, the heat is dissipated by the radiator 44 to achieve preheating of the battery pack 32 and heating of the pipeline.

[0028] In summer mode, the fifth solenoid valve 41 switches to the refrigerator 42. The paraffin in the phase change heat storage mechanism 48 vaporizes and is driven by the second circulation pump 47 to liquefy in the refrigerator and release heat, thereby achieving cabin air conditioning. In winter mode, the fifth solenoid valve 41 switches to the radiator 44, and the medium vapor dissipates heat and condenses through the radiator. The released heat is used to preheat the battery pack and prevent the hydraulic pipeline from freezing.

[0029] The present invention significantly improves the utilization rate of waste heat of hydraulic oil through the multi-circuit integrated design of the first heat exchanger 6, effectively extending the cruising range; at the same time, in summer, the latent heat of vaporization of the phase change heat storage medium is used for cooling, which significantly reduces energy consumption; in winter, the cab is heated by the waste heat of the second radiator 46, completely replacing electric heating, further extending the cruising range.

[0030] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A waste heat recovery system for a pure electric loader, characterized in that: include: A motor cooling module and a first heat exchanger (6); the motor cooling module is connected to the first heat exchanger (6); the motor cooling module is used to cool the motor and start waste heat recovery when the temperature reaches a critical value; A battery cooling module, the battery cooling module is connected to the first heat exchanger (6), and the battery cooling module is used to cool and heat the battery, maintain the operating temperature of the battery, and simultaneously perform waste heat recovery and secondary heat recovery; A hydraulic oil cooling module is connected to the first heat exchanger (6), and is used to control the circulation of the hydraulic oil and perform heat exchange through the first heat exchanger (6) to cool the hydraulic oil and recover waste heat; A waste heat recovery module, connected to the first heat exchanger (6), for converting heat into electrical energy and storing it as a backup power source; The phase change heat storage module is connected to the battery cooling module and is used for secondary heat recovery of the coolant after waste heat recovery.

2. A pure electric loader waste heat recovery system according to claim 1, characterized in that: The motor cooling module comprises a motor (1), a first controller (2), a flow pump (3), a first temperature sensor (4) and a first solenoid valve (5); the motor (1) is electrically connected to the first controller (2), and the flow pump (3) is connected to the first controller (2) for controlling the flow of coolant; the first temperature sensor (4) is used to monitor the temperature of the coolant, and the first solenoid valve (5) is connected to the first heat exchanger (6); when the first temperature sensor (4) detects that the temperature reaches a critical value, the first solenoid valve (5) is connected to the first heat exchanger (6) to start waste heat recovery.

3. The waste heat recovery system for a pure electric loader according to claim 1, characterized in that: The battery cooling module includes a heater (31), a battery pack (32), a second temperature sensor (33), a second solenoid valve (34), an expansion water tank (35) and a second flow pump (36); the heater (31) is used to heat the battery pack (32), and the expansion water tank (35) forms a coolant circulation loop with the battery pack (32) through the second flow pump (36); the second temperature sensor (33) is used to monitor the temperature of the battery pack (32), and when the temperature reaches a critical value, the second solenoid valve (34) is connected to the first heat exchanger (6) to cool down; when the temperature of the coolant after waste heat recovery is greater than the critical value, the battery cooling module is connected to the phase change heat storage module to perform secondary heat recovery.

4. The waste heat recovery system for a pure electric loader according to claim 1, characterized in that: The hydraulic oil cooling module comprises a hydraulic oil tank (21), a third temperature sensor (22), a third solenoid valve (23) and a first circulation pump (24); the first circulation pump (24) drives the hydraulic oil to circulate in the hydraulic oil tank (21); the third temperature sensor (22) is used to monitor the temperature of the hydraulic oil; when the temperature reaches a critical value, the third solenoid valve (23) is connected to the first heat exchanger (6), and the hydraulic oil is subjected to heat exchange cooling and waste heat recovery through the first heat exchanger (6).

5. The waste heat recovery system for a pure electric loader according to claim 1, characterized in that: The waste heat recovery module comprises a vortex expander (64), a generator (63), a battery (62), a second controller (61), a condenser (65), a working fluid tank (66) and a working fluid pump (67); the working fluid in the working fluid tank (66) is pressurized by the working fluid pump (67) and enters the first heat exchanger (6) to absorb heat and vaporize; the vaporized working fluid steam drives the vortex expander (64) to drive the generator (63) to generate electricity, and the electrical energy is stored in the battery (62); the expanded working fluid steam is condensed by the condenser (65) and then flows back to the working fluid tank (66); the second controller (61) independently controls the circulation of the waste heat recovery module.

6. The waste heat recovery system for a pure electric loader according to claim 1, characterized in that: The phase change heat storage module includes a fourth solenoid valve (50), a fourth temperature sensor (49), a phase change heat storage mechanism (48), a second heat exchanger (46), a second circulation pump (47), a refrigerator (42), a radiator (44), a fifth solenoid valve (41), a sixth solenoid valve (43) and a seventh solenoid valve (45); the fourth temperature sensor (49) monitors the coolant temperature of the battery cooling module. When the temperature reaches a critical value, the fourth solenoid valve (50) is connected to the phase change heat storage mechanism (48), and the coolant exchanges heat with the medium in the phase change heat storage mechanism (48) through the second heat exchanger (46). After the medium is vaporized, it is driven by the second circulation pump (47) and switched to the refrigerator (42) or the radiator (44) through the fifth solenoid valve (41).

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