Wide temperature range integrated thermal management system and engineering machine

Abstract

A kind of wide temperature range integrated heat management system and engineering machinery, including battery temperature control loop, motor heat dissipation loop, cab heating loop, refrigerant circuit and fuel circuit;A battery heat exchanger is connected between battery temperature control loop and refrigerant circuit, to realize the cooling of battery pack;A heat exchange plate is connected between battery temperature control loop and cab heating loop, to realize the preheating of battery pack;The radiator in motor heat dissipation loop is connected with a radiator bypass branch through three-way proportional valve I, and battery temperature control loop and motor heat dissipation loop are connected together through four-way reversing valve, to realize the series control of battery temperature control loop and motor heat dissipation loop;Three-way proportional valve II is connected between heat exchange plate, heater core and low-temperature starting device, to realize the heating inside cab and the preheating function of battery temperature control loop.The utility model constructs a set of integrated heat management system integrated with energy interaction, waste heat recovery and intelligent temperature control.

Description

Technical Field

[0001] This utility model relates to a wide-temperature-range integrated thermal management system, belonging to the field of electric excavator technology. Background Technology

[0002] With the rapid development of electric construction machinery, building an integrated thermal management system that combines comfort, safety, and energy efficiency has become a focus of the industry. Currently, the thermal management system of small electric excavators still faces severe challenges: insufficient integration, with subsystems such as batteries, motors, and cab air conditioning operating relatively independently, lacking heat exchange and waste heat recovery mechanisms. This situation leads to low energy utilization. Furthermore, the independent system architecture results in complex piping and redundant components, increasing material costs and causing significant performance degradation in low-temperature environments. Therefore, optimizing the integrated design and energy efficiency of the thermal management system has become crucial for improving the performance of small electric excavators and overcoming market competitiveness bottlenecks. Summary of the Invention

[0003] This invention provides a wide-temperature-range integrated thermal management system. Addressing the above-mentioned pain points, this invention focuses on energy efficiency, system synergy, and wide-temperature-range adaptability, constructing an integrated thermal management system that integrates energy interaction, waste heat recovery, and intelligent temperature control.

[0004] This utility model is achieved according to the following technical solution: In a first aspect, this utility model provides a wide-temperature-range integrated thermal management system, comprising: Battery temperature control circuit, including water pump I, battery pack, and water bottle I; The motor cooling circuit includes water pump II, motor, electrical control system, radiator, and kettle II; The cab heating circuit includes water pump III, water heater, heater core, and water tank III; The refrigerant circuit includes the compressor, condenser, expansion valve, and evaporator; Fuel circuit, including fuel pump, cold start device, and fuel tank; Specifically, a battery heat exchanger is connected between the battery temperature control circuit and the refrigerant circuit to cool the battery pack; a heat exchange plate is connected between the battery temperature control circuit and the cab heating circuit to preheat the battery pack; the radiator in the motor cooling circuit is connected in parallel with a radiator bypass branch through a three-way proportional valve I; the battery temperature control circuit and the motor cooling circuit are connected together through a four-way reversing valve to achieve series control of the battery temperature control circuit and the motor cooling circuit; a three-way proportional valve II is connected between the heat exchange plate, the heater core, and the low-temperature start-up device, which on the one hand achieves heating inside the cab, and on the other hand achieves the preheating function of the battery temperature control circuit.

[0005] In some embodiments, a water temperature sensor I is connected in the battery temperature control circuit. When the water temperature sensor I detects that the water temperature is greater than a preset value, the thermal management control module controls the water pump I and the compressor to start synchronously, and the coolant exchanges heat through the battery heat exchanger. When the water temperature sensor I detects that the water temperature is less than the preset value, the thermal management control module controls the water pump I, the water pump III, and the low-temperature start-up device or the water heater to start synchronously, and the coolant exchanges heat through the heat exchange plate.

[0006] In some embodiments, a water temperature sensor II is connected in the motor heat dissipation circuit, and a fan I is configured in the radiator. When the water temperature sensor II detects that the water temperature is greater than a preset value, the thermal management control module controls the water pump II and the fan I to start synchronously, and the coolant is cooled through the radiator. When the water temperature sensor II detects that the water temperature is less than the preset value, the thermal management control module controls the water pump II to start and adjusts the three-way proportional valve I, and the coolant passes through the radiator bypass branch.

[0007] In some embodiments, the heating core is equipped with a fan II. When the ambient temperature sensor detects that the ambient temperature is lower than a preset value a, the thermal management control module controls the water pump III, the low-temperature start-up device, and the oil pump to start simultaneously, and the coolant achieves heat exchange through the low-temperature start-up device.

[0008] In some embodiments, when the ambient temperature sensor detects that the ambient temperature is lower than a preset value b, the thermal management control module controls and adjusts the four-way reversing valve to transfer the heat of the high-temperature coolant in the motor heat dissipation circuit to the low-temperature coolant in the battery temperature control circuit.

[0009] In some embodiments, a pressure sensor and / or a temperature and pressure sensor are connected to the refrigerant circuit.

[0010] In some embodiments, the water heater is a WPTC water heater and is powered by a battery pack. The WPTC water heater heats both the battery pack and the cab.

[0011] In some embodiments, a thermal expansion valve is connected in series in the pipeline between the condenser and the evaporator, and an electronic expansion valve is connected in series in the pipeline between the condenser and the battery heat exchanger.

[0012] Secondly, this utility model provides an engineering machinery equipped with the aforementioned wide-temperature-range integrated thermal management system.

[0013] In some embodiments, the construction machinery includes an electric excavator.

[0014] The beneficial effects of this utility model are: 1. This utility model achieves energy interaction and waste heat recovery mechanism between systems (air conditioner, battery, motor) through the coordinated combination of a four-way reversing valve and a three-way proportional valve, which significantly improves energy utilization.

[0015] 2. This utility model uses a dual expansion valve for precise temperature control and integrates a low-temperature start-up device with a high-efficiency WPTC water heater to significantly improve wide temperature range adaptability while optimizing low-temperature start-up energy consumption. Attached Figure Description

[0016] The accompanying drawings, as part of this utility model, are used to provide a further understanding of the present utility model. The illustrative embodiments and descriptions of the present utility model are used to explain the present utility model, but do not constitute an undue limitation of the present utility model. Obviously, the drawings described below are merely some embodiments; those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0017] In the attached diagram: Figure 1 This is a schematic diagram of the wide-temperature-range integrated thermal management system of this utility model; Figure 2 This is a schematic diagram showing the battery temperature control circuit and the motor heat dissipation circuit connected in series in this utility model; Figure 3 This is a flowchart of the control system of this utility model; Figure 4 This is a flowchart of the combined heating process of the low-temperature start-up device and the WPTC heater.

[0018] Attached diagram labels: 100-Battery temperature control circuit, 200-Motor heat dissipation circuit, 300-Cabin heating circuit, 400-Refrigerant circuit, 500-Fuel circuit.

[0019] It should be noted that these accompanying drawings and textual descriptions are not intended to limit the scope of the present invention in any way, but rather to illustrate the concept of the present invention to those skilled in the art by referring to specific embodiments. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. The following embodiments are used to illustrate this utility model, but are not intended to limit the scope of this utility model.

[0021] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0022] In existing thermal management systems, the battery temperature control circuit, motor heat dissipation circuit, and cab cooling / heating circuit operate independently, resulting in redundant and complex component configurations. There is a lack of energy interaction mechanisms between these systems, leading to low energy utilization and significant waste of heat. Currently, most thermal management systems utilize heat pump air conditioning, with cab heating typically employing PTC heating solutions. For short-duration operation scenarios, these solutions suffer from high energy consumption during low-temperature startup and poor adaptability to a wide temperature range.

[0023] This utility model focuses on mini electric excavators. Addressing the space constraints of a compact machine layout, it aims to construct an energy-efficient and high-performance thermal management system. Through the synergistic combination of a four-way directional valve and a three-way proportional valve, it cleverly achieves energy interaction and waste heat recovery mechanisms between different subsystems (air conditioning, battery, and motor), significantly improving energy utilization. The system integrates a low-temperature start-up device and a high-efficiency WPTC water heater, forming a multi-mode heat supply to ensure rapid start-up and operational stability in low-temperature environments, while optimizing the configuration of heat sources. The air conditioning system employs a combined control strategy of electronic expansion valves and thermostatic expansion valves on the cooling side, achieving precise allocation and on-demand supply of cooling capacity. The entire system provides a highly efficient and intelligent thermal management solution for mini electric excavators to operate stably in a wide temperature range of -30℃ to 45℃.

[0024] like Figure 1 As shown, the wide-temperature-range integrated thermal management system is divided into a coolant circuit, a refrigerant circuit 400, and a fuel circuit 500 according to the fluid medium type. The coolant circuit is further subdivided into a battery temperature control circuit 100, a motor cooling circuit 200, and a cab heating circuit 300.

[0025] The battery temperature control circuit 100 includes a water pump 1, a heat exchanger, a battery heat exchanger, a battery pack, a four-way reversing valve, an expansion tank 1, and a water temperature sensor 1; the motor cooling circuit 200 includes a water pump 2, a motor, an electronic control system, a three-way proportional valve 1, a radiator, a four-way reversing valve, an expansion tank 2, a water temperature sensor 2, and a fan 1; the cab heating circuit 300 includes a water pump 3, a WPTC water heater, a three-way proportional valve 2, a heater core, an expansion tank 3, and a fan 2; the refrigerant circuit 400 includes an electric compressor, a condenser, a thermal expansion valve, an electronic expansion valve, an evaporator, a battery heat exchanger, a pressure sensor, and a PT sensor (i.e., a temperature and pressure sensor); and the fuel circuit 500 includes an electromagnetic water-fuel pump, a low-temperature starting device, and a fuel tank.

[0026] The following provides a further explanation of the working process of the aforementioned battery temperature control circuit, motor heat dissipation circuit, cab heating circuit, refrigerant circuit, and fuel circuit.

[0027] (1) Battery temperature control loop: This loop can provide dual protection for low-temperature preheating and high-temperature cooling of the battery pack, ensuring that the battery pack operates within the optimal temperature range (20-30℃) between -30℃ and 45℃. When the temperature is ≥35℃ (error ±1.5℃) as monitored by water temperature sensor 1, the battery pack sends a cooling request through the BMS battery management system. At this time, water pump 1 and electric compressor start synchronously. The coolant flows through the heat exchange plate and battery heat exchanger through water pump 1, and heat exchange is achieved through the battery heat exchanger. Then it flows through the battery pack and returns through the four-way reversing valves 4 and 2, forming a coolant circulation loop, and finally achieving the cooling of the battery pack. When operating at low temperatures, if the coolant temperature monitored by water temperature sensor 1 is ≤5℃ (error ±1.5℃), the battery pack sends a preheating request through the BMS battery management system. At this time, water pump 1 and the low-temperature start-up device or WPTC water heater are turned on simultaneously. The coolant flows through water pump 1, through the heat exchange plate and the battery heat exchanger, where heat exchange is achieved. It then flows through the battery pack and returns through the four-way reversing valves 4 and 2, forming a coolant circulation loop, ultimately achieving preheating of the battery pack. Figure 1 , Figure 3 As shown.

[0028] (2) Motor cooling circuit: This circuit can ensure that the motor and electronic control system are ≤80℃ and the peak efficiency is ≥96%. Under high temperature conditions, the coolant temperature monitored by water temperature sensor 2 is ≥65℃ (error ±1.5℃). At this time, the motor and electronic control system issue a cooling demand. At this time, water pump 2 and fan 1 are turned on simultaneously. The coolant flows through water pump 2 through the motor and electronic control system, through ports 1 and 3 of three-way proportional valve 1, through the radiator for cooling, and then flows back through ports 1 and 3 of four-way reversing valve to form a coolant circulation circuit, ultimately achieving cooling of the motor and electronic control system. Under low temperature conditions, the coolant temperature monitored by water temperature sensor 2 is ≤35℃ (error ±1.5℃). At this time, water pump 2 is turned on. The coolant flows through water pump 2 through the motor and electronic control system, through ports 1 and 2 of three-way proportional valve 1, through the radiator bypass branch, and then flows back through ports 1 and 3 of four-way reversing valve to form a coolant circulation circuit, ultimately achieving cooling of the motor and electronic control system. Figure 1 , Figure 3 As shown.

[0029] (3) Cab Heating Circuit: The cab heating circuit achieves its heating function through a combination of a low-temperature start-up device and a WPTC water heater. The low-temperature start-up device can quickly raise the system's base temperature in extremely cold environments, shortening the warm-up cycle. The WPTC water heater can accurately replenish energy when residual heat is insufficient, based on its efficient electric heating capacity. When the ambient temperature is below -15℃, the water pump 3, the low-temperature start-up device, and the electromagnetic oil pump are turned on simultaneously. The coolant flows through the water pump 3 and the low-temperature start-up device to achieve heat exchange. It is then divided into two branches through the two ports of the three-way proportional valve 2. One branch passes through the heater core and is then blown out by the fan 2 to heat the cab interior. The other branch passes through the heat exchange plate to achieve the preheating function of the battery temperature control circuit. Figure 1 , Figure 3 , Figure 4 As shown.

[0030] (4) Battery temperature control circuit and motor heat dissipation circuit are connected in series: By combining the three-way proportional valve 1 and the four-way reversing valve, the battery temperature control circuit and the motor heat dissipation circuit are connected in series for control. By constructing a waste heat recovery channel across the system, the heat generated by the motor during operation is transferred to the battery pack via the coolant, realizing the passive preheating function in low-temperature environments. The coolant in the entire series circuit flows through water pump 2, motor, electrical control system, three-way proportional valve 1, four-way reversing valve 1 and 2, water pump 1, heat exchange plate, battery heat exchanger, battery pack, four-way reversing valve 4 and 3, and returns to water pump 2. When the high-temperature coolant in the motor heat dissipation circuit flows through the internal flow channel of the battery pack, it transfers heat to the low-temperature coolant in the battery temperature control circuit through direct contact heat conduction, so that the battery pack temperature gradually rises to the suitable range for starting. This circuit optimizes the compactness and energy efficiency of the whole machine thermal management system, and is especially suitable for low-temperature operation scenarios above -30℃, such as Figure 2 , Figure 3 , Figure 4 As shown.

[0031] In summary, this utility model provides a wide-temperature-range integrated thermal management system, achieving the following functions and effects: This utility model targets a thermal management system. Based on the precise adjustment of dual expansion valves, it achieves reasonable distribution of cooling capacity and integrates a composite heating strategy of low-temperature start-up device and high-efficiency WPTC heater. Through the coordinated combination of four-way reversing valve and three-way proportional valve, it realizes the series connection of battery temperature control circuit and motor heat dissipation circuit, and builds an energy interaction and waste heat recovery mechanism between systems (air conditioner, battery, motor), which significantly improves energy efficiency and wide temperature range adaptability, while optimizing low-temperature start-up energy consumption.

[0032] The following describes the engineering machinery provided by this utility model. The engineering machinery described below can be referred to in correspondence with the wide temperature range integrated thermal management system described above.

[0033] The engineering machinery provided by this utility model may include a wide-temperature-range integrated thermal management system as described in any of the above embodiments.

[0034] The beneficial effects achieved by the engineering machinery provided by this utility model are consistent with the beneficial effects achieved by the wide-temperature-range integrated thermal management system provided by this utility model, so they will not be repeated here.

[0035] It should be noted that the aforementioned construction machinery can be electric excavators or other electric construction machinery.

[0036] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the present invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0037] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features found in other embodiments but not others, combinations of features from different embodiments are also within the scope of protection of this invention and form different embodiments. For example, in the embodiments described above, those skilled in the art can use them in combination based on known technical solutions and the technical problems to be solved by this application.

[0038] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to a preferred embodiment, it is not intended to limit the present utility model. Any person skilled in the art can make some modifications or alterations to the above-described technical content to create equivalent embodiments without departing from the scope of the present utility model. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the scope of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A wide-temperature-range integrated thermal management system, characterized in that, include: Battery temperature control circuit, including water pump I, battery pack, and water bottle I; The motor cooling circuit includes water pump II, motor, electrical control system, radiator, and kettle II; The cab heating circuit includes water pump III, water heater, heater core, and water tank III; The refrigerant circuit includes the compressor, condenser, expansion valve, and evaporator; Fuel circuit, including fuel pump, cold start device, and fuel tank; Specifically, a battery heat exchanger is connected between the battery temperature control circuit and the refrigerant circuit to cool the battery pack; a heat exchange plate is connected between the battery temperature control circuit and the cab heating circuit to preheat the battery pack; the radiator in the motor cooling circuit is connected in parallel with a radiator bypass branch through a three-way proportional valve I; the battery temperature control circuit and the motor cooling circuit are connected together through a four-way reversing valve to achieve series control of the battery temperature control circuit and the motor cooling circuit; a three-way proportional valve II is connected between the heat exchange plate, the heater core, and the low-temperature start-up device, which on the one hand achieves heating inside the cab, and on the other hand achieves the preheating function of the battery temperature control circuit.

2. The wide-temperature-range integrated thermal management system according to claim 1, characterized in that: The battery temperature control circuit is connected to a water temperature sensor I. When the water temperature sensor I detects that the water temperature is greater than the preset value, the thermal management control module controls the water pump I and the compressor to start synchronously, and the coolant exchanges heat through the battery heat exchanger. When the water temperature sensor I detects that the water temperature is less than the preset value, the thermal management control module controls the water pump I, the water pump III, and the low temperature start-up device or water heater to start synchronously, and the coolant exchanges heat through the heat exchange plate.

3. The wide-temperature-range integrated thermal management system according to claim 1, characterized in that: A water temperature sensor II is connected in the motor cooling circuit, and a fan I is configured in the radiator. When the water temperature sensor II detects that the water temperature is greater than the preset value, the thermal management control module controls the water pump II and the fan I to start synchronously, and the coolant is cooled through the radiator. When the water temperature sensor II detects that the water temperature is less than the preset value, the thermal management control module controls the water pump II to start and adjusts the three-way proportional valve I, and the coolant flows through the radiator bypass branch.

4. The wide-temperature-range integrated thermal management system according to claim 1, characterized in that: The heating core is equipped with fan II. When the ambient temperature is lower than the preset value a by the ambient temperature sensor, the thermal management control module controls the water pump III, the low-temperature start device and the oil pump to start simultaneously, and the coolant achieves heat exchange through the low-temperature start device.

5. The wide-temperature-range integrated thermal management system according to claim 1, characterized in that: When the ambient temperature sensor detects that the ambient temperature is lower than the preset value b, the thermal management control module controls and adjusts the four-way reversing valve to transfer the heat of the high-temperature coolant in the motor cooling circuit to the low-temperature coolant in the battery temperature control circuit.

6. The wide-temperature-range integrated thermal management system according to claim 1, characterized in that: A pressure sensor and / or a temperature and pressure sensor are connected in the refrigerant circuit.

7. The wide-temperature-range integrated thermal management system according to claim 1, characterized in that: The water heater is a WPTC water heater, which is powered by a battery pack. The WPTC water heater heats both the battery pack and the cab.

8. The wide-temperature-range integrated thermal management system according to claim 1, characterized in that: A thermal expansion valve is connected in series in the pipeline between the condenser and the evaporator, and an electronic expansion valve is connected in series in the pipeline between the condenser and the battery heat exchanger.

9. An engineering machinery, characterized in that: It is equipped with the wide temperature range integrated thermal management system as described in any one of claims 1 to 8.

10. An engineering machinery according to claim 9, characterized in that: The construction machinery includes electric excavators.

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