Thermal management system for pure electric crawler crane and crane

Abstract

The embodiment of the present application provides a thermal management system and crane for a pure electric crawler crane. The method includes: the motor circuit includes a first three-way valve, a first water pump, and multiple motors, wherein the multiple motors include a hydraulic pump motor, and the motor circuit is connected to the battery circuit through a first three-way valve and a second three-way valve; the battery circuit includes a second three-way valve, a power battery, and a second water pump; the controller is configured to control the first three-way valve to connect to the first water pump and the battery circuit and disconnect from the hydraulic pump motor when there is a heating demand or heat dissipation demand for the power battery and the hydraulic pump motor, and to control the second three-way valve to connect to the second water pump and the motor circuit and disconnect from the power battery, so that the coolant in the motor circuit flows into the power battery through the first three-way valve to heat or dissipate the coolant. The above technical solution combines the multiple thermal management circuits of the crawler crane into an overall design and control, which can not only improve battery energy efficiency but also reduce costs.

Description

Technical Field

[0001] The present application relates to the technical field of engineering machinery, and in particular to a thermal management system and a crane for a pure electric crawler crane. Background Art

[0002] Due to the continuous depletion of fossil fuels and the constraints of carbon emission regulations, construction machinery is also moving towards new energy sources. A common technical approach to energy conservation and emission reduction for crawler cranes is to adopt pure electric drive, that is, crawler cranes powered by onboard power batteries. However, the use of pure electric drive brings thermal management issues for batteries and motors. In particular, pure electric drive requires high performance from batteries. Existing batteries are generally expensive and perform poorly in high and low temperature environments. Therefore, improving battery life and energy utilization efficiency is crucial.

[0003] Existing pure electric crawler cranes typically replace the engine with an electric motor while retaining the original hydraulic system. This solution offers the advantage of low cost, but it cannot utilize brake battery energy recovery, and the hydraulic system is relatively inefficient, resulting in low vehicle drive efficiency and high vibration and noise. Another pure electric crawler crane approach uses an electric motor to directly drive the travel, hoisting, slewing, and luffing mechanisms, but this requires a hydraulic system to drive the accessories, necessitating a hydraulic pump and motor within the hydraulic system. Currently, there are no mature products of this type of crawler crane, and no literature has yet explored its thermal management system. Summary of the Invention

[0004] The purpose of the embodiments of the present application is to provide a thermal management system and a crane for a pure electric crawler crane.

[0005] In order to achieve the above objectives, the present application provides, in a first aspect, a thermal management system for a pure electric crawler crane, comprising:

[0006] The motor circuit includes a first three-way valve, a first water pump and a hydraulic pump motor. The motor circuit is connected to the battery circuit through the first three-way valve and the second three-way valve. The three ends of the first three-way valve are respectively connected to the first water pump, the hydraulic pump motor and the battery circuit; the battery circuit includes a second three-way valve, a power battery and a second water pump. The three ends of the second three-way valve are respectively connected to the motor circuit, the power battery and the second water pump; the controller is electrically connected to the motor circuit and the battery circuit and is configured to control the first three-way valve to connect to the first water pump and the battery circuit and disconnect from the hydraulic pump motor when there is a heating demand or a heat dissipation demand for the power battery and the hydraulic pump motor, and to control the second three-way valve to connect to the second water pump and the motor circuit and disconnect from the power battery, so that the coolant in the motor circuit flows into the power battery through the first three-way valve to heat or dissipate the power battery.

[0007] A second aspect of the present application provides a pure electric crawler crane, comprising any one of the above-mentioned thermal management systems for a pure electric crawler crane.

[0008] Through the above technical solution, the thermal management of the battery and the motor are integrated. The battery is heated by the heat generated by the operation of the motor and dissipated through the circuit where the motor is located. The number of fans, radiators and heaters can be reduced, which not only increases the compactness of the structure and reduces the cost, but also improves the battery life and energy utilization efficiency of the battery, and can also improve the operating efficiency of the system.

[0009] Other features and advantages of the embodiments of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the following detailed description, they are used to explain the embodiments of the present application but do not constitute a limitation on the embodiments of the present application. In the accompanying drawings:

[0011] Figure 1 The following schematically shows a structural block diagram of a thermal management system 100 for a pure electric crawler crane according to an embodiment of the present application;

[0012] Figure 2 Schematically shows the coolant flow and hydraulic oil flow diagram of the thermal management system 100 in the first mode according to an embodiment of the present application;

[0013] Figure 3 Schematically shows the flow diagram of coolant, hydraulic oil, and refrigerant of the thermal management system 100 in the second mode according to an embodiment of the present application;

[0014] Figure 4 Schematically shows the flow diagram of coolant, hydraulic oil, and refrigerant of the thermal management system 100 in the third mode according to an embodiment of the present application;

[0015] Figure 5 Schematically shows the flow diagram of coolant, hydraulic oil, and refrigerant of the thermal management system 100 in the fourth mode according to an embodiment of the present application;

[0016] Figure 6 Schematically shows the flow diagram of coolant, hydraulic oil, and refrigerant of the thermal management system 100 in the fifth mode according to an embodiment of the present application;

[0017] Figure 7 Schematically shows the flow diagram of coolant, hydraulic oil, and refrigerant of the thermal management system 100 in the sixth mode according to an embodiment of the present application;

[0018] Figure 8Schematically shows the flow diagram of coolant, hydraulic oil, and refrigerant of the thermal management system 100 in the seventh mode according to an embodiment of the present application;

[0019] Figure 9 Schematically shows the flow diagram of coolant, hydraulic oil, and refrigerant of the thermal management system 100 in the eighth mode according to an embodiment of the present application;

[0020] Figure 10 Schematic diagram showing the flow directions of coolant, hydraulic oil and refrigerant in the thermal management system 100 in the ninth mode according to an embodiment of the present application. Figure 1 ;

[0021] Figure 11 Schematic diagram showing the flow directions of coolant, hydraulic oil and refrigerant in the thermal management system 100 in the ninth mode according to an embodiment of the present application. Figure 2 . DETAILED DESCRIPTION

[0022] To make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the specific implementation methods described herein are only used to illustrate and explain the embodiments of the present application and are not used to limit the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0023] This application provides a thermal management system for a pure electric crawler crane. Figure 1 As shown, in one embodiment of the present application, a thermal management system 100 for a pure electric crawler crane is provided. The thermal management system 100 includes:

[0024] The motor circuit 101 includes a first three-way valve, a first water pump and a hydraulic pump motor. Among them, the three-way valve refers to a valve device with three ports on the valve body, one inlet and two outlets (left inlet, right and bottom outlet). Among them, the water pump refers to a machine that transports liquid or pressurizes liquid. The motor refers to an electromagnetic device that realizes the conversion or transmission of electric energy according to the law of electromagnetic induction, commonly known as a motor. The motor circuit 101 is connected to the battery circuit 102 through the first three-way valve and the second three-way valve. The three ends of the first three-way valve are respectively connected to the first water pump, the hydraulic pump motor and the battery circuit. In this thermal management system, multiple motors are included, and the multiple motors include a hydraulic pump motor for specifically controlling the hydraulic pump.

[0025] Battery circuit 102 includes a second three-way valve, a power battery, and a second water pump. The power battery refers to a power source, which can be a lithium-ion battery. The three ends of the second three-way valve are connected to the motor circuit, the power battery, and the second water pump, respectively.

[0026] The controller (not shown in the figure) is configured to control the first three-way valve to connect to the first water pump and the battery circuit and disconnect from the hydraulic pump motor when there is a heating demand or heat dissipation demand for the power battery and the hydraulic pump motor, and control the second three-way valve to connect to the second water pump and the motor circuit and disconnect from the power battery, so that the coolant in the motor circuit 101 flows into the power battery through the first three-way valve to heat or dissipate heat for the power battery.

[0027] The pure electric crawler crane in this application uses different motors to drive the hoisting, luffing, slewing and traveling mechanisms, and uses a hydraulic pump motor to drive the hydraulic pump to drive the hydraulic accessories. By integrating the thermal management of the power battery and the thermal management of the hydraulic pump motor, the power battery can be heated by the heat generated by the operation of the hydraulic pump motor. The heat generated by the operation of the hydraulic pump motor can be changed by adjusting the efficiency and power of the hydraulic pump motor. Compared with the traditional method of installing a PTC heater inside the power battery to heat the battery, this heating method effectively reduces costs and is controllable. At the same time, the power battery can also dissipate heat through the motor circuit, reducing the use of fans and radiators, which can effectively reduce costs and improve the operating efficiency of the cooling system.

[0028] In one embodiment, reference Figure 1 The thermal management system 100 also includes an air-conditioning circuit 103, which includes a first heat exchanger, a first expansion valve, a gas-liquid separator, a compressor, and a condenser. The air-conditioning circuit 103 is connected to the battery circuit 101 through the first heat exchanger. Specifically, the first end of the first expansion valve is connected to the first heat exchanger, and the second end is connected to the condenser, the second expansion valve, and the one-way valve. The first end of the gas-liquid separator is connected to the first heat exchanger and the evaporator, and the second end is connected to the compressor. The first end of the compressor is connected to the gas-liquid separator, and the second end is connected to the third three-way valve. The first end of the condenser is connected to the first expansion valve, the second expansion valve, and the one-way valve, and the second end is connected to the third three-way valve.

[0029] Among them, a heat exchanger refers to a device that transfers part of the heat of a hot fluid to a cold fluid, also known as a heat exchanger. An expansion valve is a component commonly used in refrigeration systems. Its main function is to throttle, reduce pressure, and regulate flow. It is generally installed between the liquid receiver and the evaporator. The expansion valve allows the medium-temperature, high-pressure liquid refrigerant to pass through its throttling to become a low-temperature, low-pressure wet steam. The refrigerant then absorbs heat in the evaporator to achieve a cooling effect. A gas-liquid separator is a device used to separate gas and liquid. It can also be used to store refrigerant liquid. It protects the compressor when the refrigerant liquid returns after startup, operation, or defrosting (heat pump). It mainly dries the air entering the compressor to prevent liquid hammer from damaging the compressor. A compressor is a driven fluid mechanical device that raises low-pressure gas to high-pressure gas. A condenser is also a type of heat exchanger that can convert gas or vapor into liquid.

[0030] The controller is electrically connected to air conditioning circuit 103 and is further configured to, when the cab requires heating and the compressor is activated, control the refrigerant in air conditioning circuit 103 to flow sequentially through the compressor, condenser, and first expansion valve, and then to the first heat exchanger, thereby exchanging heat with the coolant in battery circuit 101. The controller also controls the refrigerant after heat exchange to flow through the gas-liquid separator and back to the compressor. Cabin heating is primarily achieved through heat pump air conditioning, which boasts high heating efficiency and integrates power battery thermal management with cab thermal management. This allows the heat pump to draw heat from the battery circuit via the first heat exchanger, effectively preventing frost.

[0031] In one embodiment, continue to refer to Figure 1 Air conditioning circuit 103 also includes a second expansion valve and an evaporator. The second expansion valve has two ends connected to the condenser and evaporator, respectively. Specifically, a first end of the second expansion valve is connected to the first expansion valve, the condenser, and the one-way valve, while a second end is connected to the evaporator. A first end of the evaporator is connected to the second expansion valve, while a second end is connected to the gas-liquid separator and the first heat exchanger.

[0032] An evaporator is a device that converts liquid substances into gaseous substances. It is also a heat exchanger that transfers heat from the process fluid to the refrigerant, causing a phase change and evaporation. In the evaporator, the refrigerant enters the evaporator as a low-pressure liquid or vapor mixture and leaves as a low-pressure gas.

[0033] If the cab requires demisting, the controller is further configured to control the refrigerant in air conditioning circuit 103 to flow sequentially through the compressor, condenser, and second expansion valve before flowing into the evaporator and then into the gas-liquid separator to defog the cab. The cab demisting circuit and heating circuit do not overlap, enabling simultaneous demisting of the cab while heating. Demisting the evaporator also cools the refrigerant, allowing heat dissipation to the cab through the evaporator circuit when required.

[0034] In one embodiment, reference Figure 1 The air-conditioning circuit 103 also includes a third three-way valve, an air-conditioning radiator, a one-way valve and a second expansion valve. The three ends of the third three-way valve are respectively connected to the compressor, the condenser and the air-conditioning radiator. Specifically, the first end of the third three-way valve is connected to the compressor, the second end is connected to the condenser, and the third end is connected to the air-conditioning radiator. The first end of the air-conditioning radiator is connected to the third three-way valve, and the second end is connected to the one-way valve. The first end of the one-way valve is connected to the air-conditioning radiator, and the second end is connected to the first expansion valve, the second expansion valve and the condenser. A one-way valve refers to a device in which the fluid can only flow along the water inlet, but the medium at the water outlet cannot flow back. Here, it prevents part of the air-conditioning refrigeration unit from flowing to the air-conditioning radiator due to the pressure difference, thereby reducing heat loss.

[0035] When there is a need for heat dissipation in the power battery, hydraulic pump motor, hydraulic oil and cab, the controller is also configured to: control the third three-way valve to be connected to the compressor and the air-conditioning radiator and disconnected from the condenser, so that the refrigerant in the air-conditioning circuit 103 flows into the air-conditioning radiator through the compressor, and flows into the compressor after flowing through the one-way valve, the second expansion valve, the evaporator and the gas-liquid separator.

[0036] The power battery thermal management and cab thermal management are integrated, and the cab is separately equipped with an air-conditioning radiator. When the power battery does not need to exchange heat with the cab, the cab can also complete the heat dissipation separately through the air-conditioning radiator through the circuit where the condenser is located. When the power battery needs to exchange heat with the cab, heat can be exchanged through the first heat exchanger, which can well realize the power battery thermal management and cab thermal management, and can effectively improve the operating efficiency of the system and the energy utilization efficiency of the power battery.

[0037] In one embodiment, continue to refer to Figure 1, the condenser includes a PTC heater. The controller is also configured to: when there is a heating demand in the cab and the compressor is not started, control the PTC heater to enter the electric heating mode to heat the cab through PTC electric heating. Among them, the PTC heater refers to an automatic constant temperature, energy-saving electric heater, also known as a PTC electric heater. The PTC electric heater has three heating modes including: infrared heating, electromagnetic heating and resistance heating. In this technical solution, the PTC heater can adopt the electromagnetic heating mode to heat the cab when there is a heating demand in the cab and the compressor is not started.

[0038] In one embodiment, the condenser includes a fan, and the controller is further configured to control the fan to activate when the cab needs to be heated or cooled to enhance the heat exchange rate of the air conditioning circuit 103. A fan is a device that delivers air. In this technical solution, the fan may be a blower, configured to deliver air to enhance the heat exchange rate of the cab when the cab needs to be heated or cooled.

[0039] In one embodiment, reference Figure 1 The motor circuit 101 further includes a fourth three-way valve, the three ends of which are connected to the hydraulic pump motor, the first water pump, and the second heat exchanger, respectively. Specifically, the first end of the fourth three-way valve is connected to the hydraulic pump motor, the second end is connected to the fifth three-way valve, and the third end is connected to the second heat exchanger. The first end of the hydraulic pump motor is connected to the first three-way valve and the battery circuit, and the second end is connected to the fourth three-way valve. The first end of the first three-way valve is connected to the first water pump, the second end is connected to the hydraulic pump motor and the battery circuit, and the third end is connected to the battery circuit.

[0040] The thermal management system also includes a hydraulic circuit 104, comprising a second heat exchanger, a hydraulic oil tank, and a hydraulic pump. Hydraulic circuit 104 is connected to the motor circuit via the second heat exchanger. Specifically, the first end of the hydraulic oil tank is connected to the second heat exchanger, and the second end is connected to the hydraulic pump. The first end of the hydraulic pump is connected to the hydraulic oil tank, and the second end is connected to the unloading valve and the control valve.

[0041] The hydraulic pump is mechanically connected to the hydraulic pump motor. The hydraulic oil tank is a container used to store the oil required to ensure the operation of the hydraulic system. The hydraulic pump is an energy conversion device that converts mechanical energy into fluid pressure energy, providing energy for the hydraulic oil.

[0042] The controller is electrically connected to the hydraulic circuit 104 and is also configured to: when there is a need to heat the hydraulic oil in the hydraulic circuit 104, control the hydraulic pump motor to start to drive the hydraulic pump to work, so that the hydraulic oil in the hydraulic circuit 104 flows to the second heat exchanger, and heats the hydraulic oil by exchanging heat with the coolant of the motor circuit 101.

[0043] In one embodiment, the hydraulic circuit 104 further includes a control valve and a hydraulic cylinder, and the control valve and the hydraulic cylinder are connected. Specifically, the first end of the control valve is connected to the hydraulic cylinder, and the second end is connected to the hydraulic pump and the unloading valve. The first end of the hydraulic cylinder is connected to the second heat exchanger and the unloading valve, and the second end is connected to the control valve. Among them, the control valve refers to an element used to control the pressure, flow and direction of the liquid in the hydraulic transmission system or hydraulic control system, and the control valve is also called a hydraulic control valve. The hydraulic cylinder generally refers to a hydraulic cylinder, which is a hydraulic actuator that converts hydraulic energy into mechanical energy and performs linear reciprocating motion (or swinging motion).

[0044] The controller is also configured to: when there is a need to dissipate heat of the hydraulic oil in the hydraulic circuit 104, control the hydraulic oil in the hydraulic oil tank to flow into the second heat exchanger through the hydraulic pump, and control the hydraulic oil in the hydraulic oil tank to flow through the hydraulic pump, the control valve and the hydraulic cylinder in sequence and then flow into the second heat exchanger to exchange heat with the coolant in the motor circuit 101.

[0045] In one embodiment, the battery circuit 102 also includes a first expansion tank. Specifically, the first end of the first expansion tank is connected to the second water pump, and the second end is connected to the power battery. The first end of the second water pump is connected to the first expansion tank, and the second end is connected to the second three-way valve. The first end of the power battery is connected to the motor circuit and the second three-way valve, and the second end is connected to the first expansion tank. The first end of the second three-way valve is connected to the motor circuit and the power battery, the second end is connected to the second water pump, and the third end is connected to the motor circuit. Among them, the expansion tank refers to a device that enables liquid to expand freely and reduce pressure fluctuations in the system, and can also serve as a storage tank for liquid refrigerant.

[0046] The controller is also configured to: when there is a need to heat the power batteries, control the coolant in the motor circuit 101 to flow into the power battery after passing through the first water pump and the first three-way valve, and then flow through the first expansion tank, the second water pump, and the second three-way valve to flow into the hydraulic pump motor, and then flow into the first water pump through the fourth three-way valve to heat the power battery.

[0047] In one embodiment, the battery circuit 102 further includes a first expansion tank, and the motor circuit 101 further includes a radiator, a second expansion tank, and a fifth three-way valve. The three ends of the fifth three-way valve are respectively connected to the radiator, the first water pump, and the hydraulic pump motor. Specifically, the first end of the fifth three-way valve is connected to the fourth three-way valve, the second end is connected to the radiator, and the third end is connected to the first water pump and the first expansion tank. The first end of the second expansion tank is connected to the first water pump and the fifth three-way valve, and the second end is connected to the radiator. The first end of the radiator is connected to the first water pump, and the second end is connected to the fifth three-way valve. The first end of the first water pump is connected to the first three-way valve, and the second end is connected to the second expansion valve and the fifth three-way valve. The term "radiator" generally refers to a series of devices used to release heat. If both the hydraulic pump motor and the power battery require heat dissipation, the controller is further configured to determine the coolant temperature in the motor circuit and control the first, second, and fifth three-way valves based on the coolant temperature in the motor circuit. Specifically, it is necessary to determine whether the coolant temperature in the motor circuit 101 exceeds the maximum suitable operating temperature of the power battery in the battery circuit 102. The maximum suitable operating temperature of the power battery is determined by the properties of the power battery itself. For example, in this technical solution, the power battery can be a lithium-ion battery. Generally, the maximum suitable operating temperature of a lithium-ion battery is 45°C, while the maximum suitable operating temperature of the hydraulic pump motor is 70°C, and the maximum suitable temperature of the hydraulic oil is 80°C. Temperature sensors (not shown) are installed on the power battery and the hydraulic pump motor to monitor the temperature of the coolant in the power battery and motor circuits.

[0048] In one embodiment, when the coolant temperature in the motor circuit 101 is less than or equal to the first temperature threshold of the power battery, for example, when the coolant temperature is 35°C, the controller is further configured to: control the first three-way valve to be connected to the first water pump and the battery circuit and disconnected from the hydraulic pump motor, control the second three-way valve to be connected to the second water pump and the motor circuit and disconnected from the power battery, control the fifth three-way valve to be connected to the hydraulic pump motor and the radiator and disconnected from the first water pump, so as to control the coolant in the motor circuit 101 to flow into the radiator after passing through the first water pump, the first three-way valve, the power battery, the first expansion tank, the second water pump, the hydraulic pump motor, and the fifth three-way valve in sequence, and then flow into the first water pump through the second expansion tank to dissipate heat from the power battery and the hydraulic pump motor.

[0049] In one embodiment, the radiator includes a fan. A fan is a device that assists in cooling, accelerating the rate of cooling. In this technical solution, the fan may be a cooling fan. The controller is further configured to activate the cooling fan when the hydraulic pump motor requires heat dissipation, thereby reducing the temperature of the coolant in the motor circuit 101.

[0050] In one embodiment, when the coolant temperature in the motor circuit 101 is greater than a first temperature threshold, for example, when the coolant temperature is 55° C., the controller is further configured to: control the first three-way valve to connect to the first water pump and the hydraulic pump motor and disconnect from the battery circuit; control the fifth three-way valve to connect to the hydraulic pump motor and the radiator and disconnect from the first water pump, so as to control the coolant in the motor circuit to flow into the radiator after passing through the first water pump, the first three-way valve, the hydraulic pump motor, and the fifth three-way valve in sequence, and then flow into the first water pump through the second expansion tank to dissipate heat from the hydraulic pump motor; control the second three-way valve to connect to the second water pump and the power battery and disconnect from the motor circuit, so as to allow the coolant in the battery circuit 102 to flow into the first heat exchanger after passing through the second water pump, the second three-way valve, and the power battery in sequence, so that the coolant in the battery circuit 102 exchanges heat with the refrigerant in the air-conditioning circuit 103 through the first heat exchanger, and then flows into the second water pump through the first expansion tank to reduce the temperature of the coolant and dissipate heat from the power battery.

[0051] In one embodiment, the air-conditioning circuit 103 also includes a first expansion valve, a first heat exchanger, a third three-way valve, an air-conditioning radiator, a one-way valve and a second expansion valve. The three ends of the third three-way valve are respectively connected to the compressor, the condenser and the air-conditioning radiator. When the coolant temperature in the motor circuit is greater than the first temperature threshold, for example, when the coolant temperature is 55°C and there is no heat dissipation demand and heating demand in the cab, the controller is also configured to: control the third three-way valve to be connected to the compressor and the air-conditioning radiator, and disconnect it from the condenser, so that the refrigerant in the air-conditioning circuit 103 flows into the air-conditioning radiator through the compressor, and flows into the first heat exchanger through the one-way valve and the first expansion valve in sequence to dissipate heat for the power battery, and control the refrigerant after heat exchange to flow into the compressor through the gas-liquid separator.

[0052] In one embodiment, when the coolant temperature in the motor circuit 101 is greater than the first temperature threshold, for example, when the coolant temperature is 55°C, and there is a heat dissipation demand in the cab, the controller is further configured to: control the third three-way valve to be connected to the compressor and the air-conditioning radiator, and disconnected from the condenser, so that the refrigerant in the air-conditioning circuit flows into the air-conditioning radiator through the compressor, and flows into the first heat exchanger through the one-way valve, the second expansion valve, and the evaporator in sequence to dissipate heat to the power battery and the cab, and control the refrigerant after heat exchange to flow into the compressor through the first expansion valve, the second expansion valve, the evaporator, and the gas-liquid separator.

[0053] In one embodiment, when the coolant temperature in the motor circuit 101 is greater than the first temperature threshold, for example, when the coolant temperature is 55°C, and the difference between the indoor temperature of the cab and the second temperature threshold is greater than or equal to the preset difference, the controller is further configured to: control the third three-way valve to be connected to the compressor and the condenser, and disconnected from the air-conditioning radiator, so that the refrigerant in the air-conditioning circuit 103 flows into the condenser through the compressor, and flows into the first heat exchanger through the first expansion valve to exchange heat with the coolant of the power battery, and control the refrigerant after heat exchange to flow into the compressor through the gas-liquid separator.

[0054] In one embodiment, when the coolant temperature in the motor circuit 101 is greater than the first temperature threshold, for example, when the coolant temperature is 55°C, and the difference between the indoor temperature and the second temperature threshold is less than the preset difference, the controller is further configured to: control the third three-way valve to be connected to the compressor, the condenser and the air-conditioning radiator, so that the refrigerant in the air-conditioning circuit 103 passes through the compressor and the third three-way valve, flows through the air-conditioning radiator and the condenser respectively, and flows through the first expansion valve, the first heat exchanger and the gas-liquid separator in sequence before flowing into the compressor.

[0055] In one embodiment, a pure electric crawler crane is provided, including the thermal management system for the pure electric crawler crane described above. Among them, the crawler crane is a self-propelled crane used for high-rise building construction, and is a boom rotary crane that uses crawler tracks to travel. The crawler tracks have a large ground contact area, good passability, strong adaptability, can travel with loads, and are suitable for hoisting operations at construction sites. Various operations such as excavation, tamping, and piling can be performed. Crawler cranes are flexible to operate, easy to use, have a large lifting capacity, can travel with loads on flat and solid roads, and can become excavators or pile drivers after replacing the working device. They are multifunctional machines. A pure electric crawler crane refers to a crawler crane that is driven by a vehicle-mounted power battery.

[0056] The above technical solution combines the crawler crane's hydraulic cooling, motor cooling, battery thermal management, and cab thermal management into an integrated design and control. This can reduce the number of fans, radiators, and heaters, not only increasing the compactness of the structure and reducing costs, but also improving battery life and energy efficiency. The battery is heated by the heat generated by the motor's operation, and the heat generated by the motor's operation can be adjusted by adjusting the efficiency and power of the hydraulic pump motor. Compared to the traditional method of heating the battery through an internally installed PTC heater, this technical solution can quickly increase the hydraulic oil temperature and the operating efficiency of the hydraulic system.

[0057] In such Figure 2As shown in FIG. 1 , in one embodiment, a coolant flow diagram of the thermal management system 100 in the first mode is provided. In the first mode, the ambient temperature is low, for example, below -10°C. At this time, the hydraulic pump motor starts and enters low-efficiency mode to generate more heat. The hydraulic pump motor's normal mode converts electrical energy into mechanical energy, generating a small amount of heat in the process. Low-efficiency mode converts more electrical energy into heat. The coolant temperature in the battery circuit 102 does not reach the heat pump heating temperature in the air conditioning circuit 103. The cab cannot be heated by the heat pump air conditioner. The compressor does not start, the refrigerant does not flow, and the PTC heater activates to heat the cabin. A heat pump air conditioner can refer to a system with both cooling and heating functions. The heat pump's operating principle is a mechanical device that forces heat from a low-temperature object to a high-temperature object in a reverse cycle. This mechanical device generates a large amount of heat with only a small amount of reverse cycle net work, effectively utilizing otherwise unusable, low-quality heat energy to achieve energy savings. Specifically, the heat pump air conditioner is a condensing system consisting of a compressor, a condenser, a first expansion valve, and a first heat exchanger. In this technical solution, the heat source for the heat pump air conditioner comes from the heat exchanged between the first heat exchanger and the battery circuit. When heating the power battery, hydraulic oil, and cab is required, the motor circuit 101 is connected to the battery circuit 102 and the hydraulic circuit 104. The power battery and hydraulic oil are heated by the heat generated by the operation of the hydraulic pump motor.

[0058] The controller is configured to: control the PTC heater to enter the electric heating mode to heat the cab; control the first end of the first three-way valve to be connected to the first water pump, the second end to be disconnected from the hydraulic pump motor and the battery circuit, and the third end to be connected to the battery circuit; and control the first end of the second three-way valve to be disconnected from the power battery and the motor circuit, the second end to be connected to the second water pump, and the third end to be connected to the motor circuit, so that the coolant in the motor circuit 101 flows into the power battery through the first three-way valve to heat the power battery; control the first end of the fourth three-way valve to be connected to the hydraulic pump motor, the second end to be connected to the fifth three-way valve, and the third end to be connected to the second heat exchanger; and control the first end of the fifth three-way valve to be connected to the fourth three-way valve, the second end to be disconnected from the radiator, and the third end to be connected to the first water pump, so that the hydraulic oil in the hydraulic circuit 104 flows through the hydraulic oil tank, through the hydraulic pump and the unloading valve in sequence, and flows into the second heat exchanger and the coolant in the motor circuit 101 for heat exchange to heat the hydraulic oil.

[0059] In such Figure 3As shown, in one embodiment, a coolant and hydraulic oil flow diagram for the thermal management system 100 in the second mode is provided. In the second mode, the ambient temperature is low, and the hydraulic pump motor is in a low-efficiency mode to generate more heat. However, the coolant temperature in the battery circuit 102 reaches the heat pump heating temperature in the air conditioning circuit 103. The cab can be heated by the heat pump air conditioning. The compressor starts, refrigerant flows, and the PTC heater is selected to be turned off based on the current heating rate of the cab. When heating of the power battery, hydraulic oil, and cab is required, the motor circuit 101 is connected to the battery circuit 102 and the hydraulic circuit 104. The power battery and hydraulic oil are heated by the heat generated by the operation of the hydraulic pump motor. The battery circuit 102 is also connected to the air conditioning circuit 103, and the air conditioning circuit 103 exchanges heat with the battery circuit 102 via a first heat exchanger.

[0060] The controller is configured to: control the first end of the first three-way valve to be connected to the first water pump, the second end to be disconnected from the hydraulic pump motor and the battery circuit, and the third end to be connected to the battery circuit; and control the first end of the second three-way valve to be disconnected from the power battery and the motor circuit, the second end to be connected to the second water pump, and the third end to be connected to the motor circuit, so that the coolant in the motor circuit 101 flows into the power battery through the first three-way valve to heat the power battery; control the first end of the fourth three-way valve to be connected to the hydraulic pump motor, the second end to be connected to the fifth three-way valve, and the third end to be connected to the second heat exchanger; and control the first end of the fifth three-way valve to be connected to the fourth three-way valve, the second end to be disconnected from the radiator, and the third end to be connected to the first water pump. The first end of the third three-way valve is controlled to be connected to the compressor, the second end is connected to the condenser, and the third end is disconnected from the air-conditioning radiator; the first end of the condenser is controlled to be connected to the first expansion valve and disconnected from the one-way valve and the second expansion valve, and the second end is connected to the third three-way valve, so that the refrigerant in the air-conditioning circuit 103 passes through the compressor, flows through the third three-way valve, the condenser, and the first expansion valve in sequence, and flows into the first heat exchanger and the coolant in the battery circuit 102 for heat exchange to heat the cab.

[0061] In such Figure 4 As shown in FIG. , in one embodiment, a flow diagram of the coolant, hydraulic oil, and refrigerant of the thermal management system 100 in the third mode is provided. In the third mode, the coolant temperature in the battery circuit 102 has reached the temperature required for vehicle warm-up, the vehicle can operate normally, and the hydraulic pump and motor are in normal mode. Vehicle warm-up completion means that the vehicle engine has reached normal operating temperature. At this time, if the cab needs to be defogged while being heated, then:

[0062] The controller is configured to: control the first end of the third three-way valve to be connected to the compressor, the second end to be connected to the condenser, and the third end to be disconnected from the air-conditioning radiator, and control the first end of the condenser to be connected to the first expansion valve and the second expansion valve and disconnected from the one-way valve, and the second end to be connected to the third three-way valve, so that the refrigerant in the air-conditioning circuit flows to the second expansion valve after passing through the condenser, and flows through the evaporator and the gas-liquid separator in sequence to defog the cab.

[0063] In such Figure 5 As shown in FIG. 1 , in one embodiment, a coolant and hydraulic oil flow diagram for the thermal management system 100 in a fourth mode is provided. In the fourth mode, there is no need for heating or cooling the cab, but there is a need to dissipate heat from the hydraulic pump motor, power battery, and hydraulic oil. The compressor in the air conditioning circuit 103 is not activated, and refrigerant does not flow. At this point, it is necessary to determine whether the coolant temperature in the motor circuit 101 exceeds the maximum suitable operating temperature of the power battery in the battery circuit 102. The maximum suitable operating temperature of the power battery is determined by the properties of the power battery. For example, in this technical solution, the power battery may be a lithium-ion battery. Generally, the maximum suitable operating temperature of a lithium-ion battery is 45°C, while the maximum suitable operating temperature of the hydraulic pump motor is 70°C, and the maximum suitable temperature of the hydraulic oil is 80°C. Temperature sensors (not shown) are installed on both the power battery and the hydraulic pump motor to monitor the temperature of the coolant in the power battery and motor circuits. When the coolant temperature in the motor circuit 101 exceeds the maximum suitable operating temperature of the power battery, the motor circuit 101 and the battery circuit 102 are disconnected to prevent excessive coolant temperature from damaging the power battery. Heat is dissipated separately from the hydraulic pump motor and the power battery. When the coolant temperature in the motor circuit 101 is less than or equal to the maximum suitable operating temperature of the power battery, the motor circuit 101 and the battery circuit 102 are connected, and the hydraulic pump motor and the power battery dissipate heat together through the radiator in the motor circuit 101.

[0064] In the fourth mode, the coolant temperature in the motor circuit 101 is less than or equal to the maximum suitable operating temperature of the power battery. The motor circuit 101 and the battery circuit 102 are connected. The hydraulic pump motor and the power battery dissipate heat together through the radiator in the motor circuit 101. The hydraulic circuit 104 is also connected to the motor circuit 101 and dissipates heat through the radiator.

[0065] The controller is configured to: control the first end of the first three-way valve to be connected to the first water pump, the second end to be disconnected from the hydraulic pump motor and the battery circuit, and the third end to be connected to the battery circuit; and control the first end of the second three-way valve to be disconnected from the power battery and the motor circuit, the second end to be connected to the second water pump, and the third end to be connected to the motor circuit, so that the coolant in the motor circuit 101 flows into the power battery through the first three-way valve, and flows through the first expansion tank, the second water pump, the second three-way valve in sequence, flows into the hydraulic pump motor, and then flows through the fourth three-way valve, the fifth three-way valve in sequence, and flows into Air conditioning radiator to dissipate heat for the power battery and the hydraulic pump motor; control the first end of the fourth three-way valve to be connected to the hydraulic pump motor, the second end to be connected to the fifth three-way valve, and the third end to be connected to the second heat exchanger, and control the first end of the fifth three-way valve to be connected to the fourth three-way valve, the second end to be connected to the radiator, and the third end to be disconnected from the first water pump. The hydraulic oil in the hydraulic circuit 104 flows into the hydraulic pump through the hydraulic oil tank, and flows into the unloading valve, the control valve and the hydraulic cylinder respectively, and then flows into the second heat exchanger and the coolant in the motor circuit 101 for heat exchange to dissipate heat for the hydraulic oil.

[0066] In such Figure 6 As shown, in one embodiment, a flow diagram of the coolant, hydraulic oil, and refrigerant of the thermal management system 100 in the fifth mode is provided. Specifically, in the fifth mode, the hydraulic pump motor, power battery, and hydraulic oil have heat dissipation requirements, while the cab has no heat dissipation or heating requirements. At this time, the coolant temperature in the motor circuit 101 is greater than the maximum suitable operating temperature of the power battery. The motor circuit 101 and the battery circuit 102 are disconnected, and the hydraulic pump motor and the power battery are cooled separately. The hydraulic circuit 104 is connected to the motor circuit 101 and dissipates heat through the radiator. The battery circuit 102 is connected to the air conditioning circuit 103, and the power battery dissipates heat through the air conditioning radiator of the air conditioning circuit 103.

[0067] The controller is configured to: control the first end of the first three-way valve to be connected to the first water pump, the second end to be connected to the hydraulic pump motor and disconnected from the battery circuit, and the third end to be disconnected from the battery circuit; and control the first end of the second three-way valve to be connected to the power battery and disconnected from the motor circuit, the second end to be connected to the second water pump, and the third end to be disconnected from the motor circuit, so that the coolant in the motor circuit 101 flows through the first three-way valve to the hydraulic pump motor, and flows through the fourth three-way valve and the fifth three-way valve in sequence before flowing into the radiator to dissipate heat from the hydraulic pump motor; control the first end of the fourth three-way valve to be connected to the hydraulic pump motor, the second end to be connected to the fifth three-way valve, and the third end to be connected to the second heat exchanger; and control the first end of the fifth three-way valve to be connected to the fourth three-way valve, the second end to be connected to the radiator, and the third end to be disconnected from the first water pump, so that the hydraulic oil in the hydraulic circuit 104 flows through the hydraulic oil tank into the hydraulic pump, and then flows into the unloading valve, the control valve, and the hydraulic cylinder respectively, and then flows into the second heat exchanger to exchange heat with the coolant in the motor circuit 101 to dissipate heat from the hydraulic oil.

[0068] At this time, although there is no demand in the cab, the power battery dissipates heat through the radiator in the air-conditioning circuit 103, so the compressor is started and the refrigerant flows.

[0069] The controller is also configured to: control the first end of the third three-way valve to be connected to the compressor, the second end to be disconnected from the condenser, and the third end to be connected to the air-conditioning radiator; and control the first end of the one-way valve to be connected to the air-conditioning radiator, the second end to be connected to the first expansion valve and disconnected from the second expansion valve and the condenser, so that the refrigerant in the air-conditioning circuit 103 flows into the first heat exchanger through the first expansion valve to exchange heat with the coolant in the battery circuit 102, and then flows through the gas-liquid separator, the compressor, and the third three-way valve in sequence, and flows into the air-conditioning radiator to dissipate heat from the power battery.

[0070] In such Figure 7 As shown, in one embodiment, a flow diagram of the coolant, hydraulic oil, and refrigerant of the thermal management system 100 in the sixth mode is provided. In the sixth mode, the ambient temperature is too high, and the hydraulic pump motor, power battery, hydraulic oil, and cab also need to dissipate heat. At this time, the coolant temperature in the motor circuit 101 is equal to the maximum suitable operating temperature of the power battery. The motor circuit 101 and the battery circuit 102 are connected. The hydraulic pump motor and the power battery are jointly cooled through the radiator in the motor circuit 101. The hydraulic circuit 104 is connected to the motor circuit 101 and dissipates heat through the radiator. The cab is cooled solely through the air conditioning radiator.

[0071] The controller is configured to: control the first end of the first three-way valve to be connected to the first water pump, the second end to be disconnected from the hydraulic pump motor and the battery circuit, and the third end to be connected to the battery circuit; and control the first end of the second three-way valve to be disconnected from the power battery and the motor circuit, the second end to be connected to the second water pump, and the third end to be connected to the motor circuit, so that the coolant in the motor circuit 101 flows into the power battery through the first three-way valve, and flows through the first expansion tank, the second water pump, the second three-way valve in sequence, flows into the hydraulic pump motor, and then flows through the fourth three-way valve and the fifth three-way valve in sequence, and flows into the air conditioning radiator to dissipate heat from the power battery and the hydraulic pump motor; control the first end of the fourth three-way valve to be connected to the hydraulic pump motor, the second end to be connected to the fifth three-way valve, and the third end to be connected to the second heat exchanger; and control the first end of the fifth three-way valve to be connected to the fourth three-way valve, the second end to be connected to the radiator, and the third end to be connected to the Disconnect from the first water pump, and the hydraulic oil in the hydraulic circuit 104 flows into the hydraulic pump through the hydraulic oil tank, and flows into the unloading valve, control valve and hydraulic cylinder respectively, and then flows into the second heat exchanger and the coolant in the motor circuit 101 for heat exchange to dissipate heat from the hydraulic oil; control the first end of the third three-way valve to be connected to the compressor, the second end to be disconnected from the condenser, and the third end to be connected to the air-conditioning radiator, and control the first end of the one-way valve to be connected to the air-conditioning radiator, the second end to be connected to the second expansion valve and disconnected from the first expansion valve and the condenser, so that the refrigerant in the air-conditioning circuit 103 passes through the compressor and the third three-way valve in sequence and flows into the air-conditioning radiator to dissipate heat from the cab, and control the cooled refrigerant to flow through the one-way valve, the second expansion valve, the evaporator, the gas-liquid separator, the compressor, and the third three-way valve in sequence and then flow into the air-conditioning radiator again to dissipate heat from the cab separately.

[0072] In such Figure 8 As shown, in one embodiment, a flow diagram of coolant, hydraulic oil, and refrigerant of the thermal management system 100 in the seventh mode is provided. In the seventh mode, the ambient temperature is too high, and the hydraulic pump motor, power battery, and hydraulic oil need to be cooled, and the cab also needs to be cooled. At this time, the coolant temperature in the motor circuit 101 is higher than the maximum suitable operating temperature of the power battery. The motor circuit 101 and the battery circuit 102 are disconnected, and the hydraulic pump motor and the power battery are cooled separately. The hydraulic circuit 104 is connected to the motor circuit 101 and dissipates heat through the radiator. The battery circuit 102 is connected to the air-conditioning circuit 103 and dissipates heat through the air-conditioning radiator of the air-conditioning circuit 103.

[0073] The controller is configured to: control the first end of the first three-way valve to be connected to the first water pump, the second end to be connected to the hydraulic pump motor and disconnected from the battery circuit, and the third end to be disconnected from the battery circuit; and control the first end of the second three-way valve to be connected to the power battery and disconnected from the motor circuit, the second end to be connected to the second water pump, and the third end to be disconnected from the motor circuit, so that the coolant in the motor circuit 101 flows to the hydraulic pump motor through the first three-way valve, and flows through the fourth three-way valve and the fifth three-way valve in sequence and then flows into the radiator to dissipate heat from the hydraulic pump motor; control the first end of the fourth three-way valve to be connected to the hydraulic pump motor, the second end to be connected to the fifth three-way valve, and the third end to be connected to the second heat exchanger; and control the first end of the fifth three-way valve to be connected to the fourth three-way valve, the second end to be connected to the radiator, and the third end to be connected to the first water pump. The pump is disconnected, and the hydraulic oil in the hydraulic circuit 104 flows into the hydraulic pump through the hydraulic oil tank, and flows into the unloading valve, control valve and hydraulic cylinder respectively, and then flows into the second heat exchanger and the coolant in the motor circuit 101 for heat exchange to dissipate heat from the hydraulic oil; the first end of the third three-way valve is controlled to be connected to the compressor, the second end is disconnected from the condenser, and the third end is connected to the air-conditioning radiator, and the first end of the one-way valve is controlled to be connected to the air-conditioning radiator, the second end is connected to the first expansion valve and the second expansion valve and disconnected from the condenser, so that the refrigerant in the air-conditioning circuit 103 flows into the first heat exchanger and the coolant in the battery circuit 102 through the first expansion valve for heat exchange, and then flows through the gas-liquid separator, the compressor, and the third three-way valve in sequence, and flows into the air-conditioning radiator to dissipate heat from the cab and the power battery.

[0074] In such Figure 9 As shown, in one embodiment, a flow diagram of coolant, hydraulic oil, and refrigerant of the thermal management system 100 in the eighth mode is provided. In the eighth mode, the ambient temperature is low and the vehicle load is heavy. The hydraulic pump motor, power battery, and hydraulic oil have heat dissipation requirements, and the cab has heating requirements. At this time, the coolant temperature in the motor circuit 101 is equal to the maximum suitable operating temperature of the power battery. The motor circuit 101 and the battery circuit 102 are connected. The hydraulic pump motor and the power battery jointly dissipate heat through the radiator in the motor circuit 101. The hydraulic circuit 104 is connected to the motor circuit 101 and dissipates heat through the radiator. The battery circuit 102 is also connected to the air-conditioning circuit 103 and exchanges heat through the first heat exchanger.

[0075] The controller is configured to: control the first end of the first three-way valve to be connected to the first water pump, the second end to be disconnected from the hydraulic pump motor and the battery circuit, and the third end to be connected to the battery circuit; and control the first end of the second three-way valve to be disconnected from the power battery and the motor circuit, the second end to be connected to the second water pump, and the third end to be connected to the motor circuit, so that the coolant in the motor circuit 101 flows into the power battery through the first three-way valve, and flows through the first expansion tank, the second water pump, the second three-way valve in sequence, flows into the hydraulic pump motor, and then flows through the fourth three-way valve and the fifth three-way valve in sequence, and flows into the air-conditioning radiator to dissipate heat from the power battery and the hydraulic pump motor; control the first end of the fourth three-way valve to be connected to the hydraulic pump motor, the second end to be connected to the fifth three-way valve, and the third end to be connected to the second heat exchanger, and control the first end of the fifth three-way valve to be connected to the first three-way valve. The fourth three-way valve is connected, the second end is connected to the radiator, and the third end is disconnected from the first water pump. The hydraulic oil in the hydraulic circuit 104 flows into the hydraulic pump through the hydraulic oil tank, and flows into the unloading valve, the control valve and the hydraulic cylinder respectively, and then flows into the second heat exchanger and the coolant in the motor circuit 101 for heat exchange to dissipate heat of the hydraulic oil; the first end of the third three-way valve is controlled to be connected to the compressor, the second end is connected to the condenser, and the third end is disconnected from the air-conditioning radiator, and the first end of the condenser is controlled to be connected to the first expansion valve and disconnected from the one-way valve and the second expansion valve, and the second end is connected to the third three-way valve, so that the refrigerant in the air-conditioning circuit 103 flows through the compressor through the third three-way valve, the condenser, and the first expansion valve in sequence, and flows into the first heat exchanger and the coolant in the battery circuit 102 for heat exchange to heat the cab.

[0076] In such Figure 10 As shown, in one embodiment, the flow directions of the coolant, hydraulic oil, and refrigerant of the thermal management system 100 in the ninth mode are provided. Figure 1 In the ninth mode, the ambient temperature is low and the vehicle load is heavy, requiring cooling of the hydraulic pump motor, power battery, and hydraulic oil, and heating of the cab. At this point, the coolant temperature in the motor circuit 101 exceeds the maximum suitable operating temperature of the power battery. The motor circuit 101 and the battery circuit 102 are disconnected, dissipating heat separately. The hydraulic circuit 104 is connected to the motor circuit 101, dissipating heat through the radiator, while the battery circuit 102 is connected to the air conditioning circuit 103 and exchanging heat through the first heat exchanger.

[0077] The controller is configured to: control the first end of the first three-way valve to be connected to the first water pump, the second end to be connected to the hydraulic pump motor and disconnected from the battery circuit, and the third end to be disconnected from the battery circuit; and control the first end of the second three-way valve to be connected to the power battery and disconnected from the motor circuit, the second end to be connected to the second water pump, and the third end to be disconnected from the motor circuit, so that the coolant in the motor circuit 101 flows to the hydraulic pump motor through the first three-way valve, and flows through the fourth three-way valve and the fifth three-way valve in sequence and then flows into the radiator to dissipate heat from the hydraulic pump motor; control the first end of the fourth three-way valve to be connected to the hydraulic pump motor, the second end to be connected to the fifth three-way valve, and the third end to be connected to the second heat exchanger; and control the first end of the fifth three-way valve to be connected to the fourth three-way valve, the second end to be connected to the radiator, and the third end to be connected to the fifth three-way valve. The three ends are disconnected from the first water pump, and the hydraulic oil in the hydraulic circuit 104 flows into the hydraulic pump through the hydraulic oil tank, and flows into the unloading valve, control valve and hydraulic cylinder respectively, and then flows into the second heat exchanger and the coolant in the motor circuit 101 for heat exchange to dissipate heat from the hydraulic oil; the first end of the third three-way valve is controlled to be connected to the compressor, the second end is connected to the condenser, and the third end is disconnected from the air-conditioning radiator, and the first end of the condenser is controlled to be connected to the first expansion valve and disconnected from the one-way valve and the second expansion valve, and the second end is connected to the third three-way valve, so that the refrigerant in the air-conditioning circuit 103 flows through the compressor, the third three-way valve, the condenser, and the first expansion valve in sequence, and flows into the first heat exchanger and the coolant in the battery circuit 102 for heat exchange to dissipate heat from the power battery and heat the cab.

[0078] In such Figure 11 As shown, in one embodiment, the coolant flow direction of the thermal management system 100 in the ninth mode is provided. Figure 2 At this time, the cab heating demand is small, the power battery heat dissipation is insufficient, and the heat dissipated by the power battery is too high and exceeds the heat required for cab heating. The air conditioning circuit 103 is connected to the air conditioning radiator on the basis of the ninth mode to help the power battery dissipate heat.

[0079] The controller is configured as:

[0080] The first end of the third three-way valve is controlled to be connected to the compressor, the second end is connected to the condenser, and the third end is connected to the air-conditioning radiator. The first end of the condenser is controlled to be connected to the first expansion valve and the one-way valve and disconnected from the second expansion valve, and the second end is connected to the third three-way valve, so that the refrigerant in the air-conditioning circuit 103 flows through the first expansion valve to the first heat exchanger and the coolant in the battery circuit 102 for heat exchange, and then flows into the condenser and the air-conditioning radiator respectively after passing through the compressor and the third three-way valve in sequence to dissipate heat from the power battery and heat the cab.

[0081] In one embodiment, a pure electric crawler crane is provided, comprising any one of the above-mentioned thermal management systems for a pure electric crawler crane.

[0082] It should be noted that the first, second, through ninth modes in the above embodiments are overviews and summaries of specific scenarios. For example, assume a low ambient temperature, such as below -10°C. The coolant temperature in the battery circuit 102 does not reach the heat pump heating temperature in the air conditioning circuit 103. The cab cannot be heated by the heat pump air conditioning, the compressor does not start, the refrigerant does not flow, and the PTC heater starts heating. In this case, if the crane's thermal management system 100 meets all of the above conditions, it can be considered that the thermal management system 100 is in the first mode. Those skilled in the art will appreciate that the number of modes and their specific limitations can be changed or increased or decreased as needed.

[0083] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0084] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0085] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0086] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 The steps for the function specified in one or more boxes.

[0087] In a typical configuration, a computing device includes one or more processors (CPUs), input / output interfaces, network interfaces, and memory.

[0088] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0089] Computer-readable media includes permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. The information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory computer-readable media (transitory media), such as modulated data signals and carrier waves.

[0090] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, commodity, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, commodity, or apparatus that includes the element.

[0091] The above are merely embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.

Claims

1. A thermal management system for a pure electric crawler crane, characterized in that: The thermal management system comprises: a motor circuit, comprising a first three-way valve, a first water pump, and a plurality of motors, wherein the plurality of motors include a hydraulic pump motor; the motor circuit is connected to a battery circuit via the first three-way valve and a second three-way valve; the three ends of the first three-way valve are connected to the first water pump, the hydraulic pump motor, and the battery circuit, respectively; The battery circuit includes the second three-way valve, a power battery and a second water pump, wherein the three ends of the second three-way valve are respectively connected to the motor circuit, the power battery and the second water pump; an air conditioning circuit, comprising a first heat exchanger, a first expansion valve, a second expansion valve, an evaporator, a gas-liquid separator, a compressor, a third three-way valve, an air conditioning radiator, a one-way valve, and a condenser, wherein the air conditioning circuit is connected to the battery circuit via the first heat exchanger, the two ends of the second expansion valve are respectively connected to the condenser and the evaporator, and the three ends of the third three-way valve are respectively connected to the compressor, the condenser, and the air conditioning radiator; A controller is electrically connected to the motor circuit, the battery circuit, and the air-conditioning circuit, and is configured to control the first three-way valve to connect to the first water pump and the battery circuit and disconnect from the hydraulic pump motor when there is a heating demand or a heat dissipation demand for the power battery and the hydraulic pump motor, and to control the second three-way valve to connect to the second water pump and the motor circuit and disconnect from the power battery, so that the coolant in the motor circuit flows into the power battery through the first three-way valve to heat or dissipate heat for the power battery.

2. The thermal management system for a pure electric crawler crane according to claim 1, characterized in that: The controller is also configured to: when there is a heating demand in the cab and the compressor is started, control the refrigerant in the air-conditioning circuit to flow through the compressor, the condenser, the first expansion valve in sequence and then flow into the first heat exchanger, so that the refrigerant in the air-conditioning circuit exchanges heat with the coolant in the battery circuit, and control the refrigerant after heat exchange to flow into the compressor through the gas-liquid separator.

3. The thermal management system for a pure electric crawler crane according to claim 2, characterized in that: When there is a need for defogging in the cab, the controller is further configured to: The refrigerant in the air-conditioning circuit is controlled to flow through the compressor, the condenser, and the second expansion valve in sequence, and then flow into the evaporator and the gas-liquid separator to defog the cab.

4. The thermal management system for a pure electric crawler crane according to claim 2, characterized in that: When the power battery, the hydraulic pump motor, the hydraulic oil and the cab all have heat dissipation requirements, the controller is further configured to: The third three-way valve is controlled to be connected to the compressor and the air-conditioning radiator and disconnected from the condenser, so that the refrigerant in the air-conditioning circuit flows into the air-conditioning radiator through the compressor, and flows into the compressor after flowing through the one-way valve, the second expansion valve, the evaporator and the gas-liquid separator.

5. The thermal management system for a pure electric crawler crane according to claim 2, characterized in that: The condenser includes a PTC heater; The controller is further configured to control the PTC heater to enter an electric heating mode when there is a heating demand for the cab and the compressor is not started, so as to heat the cab through the PTC heater.

6. The thermal management system for a pure electric crawler crane according to claim 2, characterized in that: The condenser includes a fan; The controller is further configured to control the fan to start up to enhance the heat exchange rate of the air conditioning circuit when there is a heating demand or a cooling demand in the cab.

7. The thermal management system for a pure electric crawler crane according to claim 1, characterized in that: The motor circuit further includes a fourth three-way valve, the three ends of which are respectively connected to the hydraulic pump motor, the first water pump and the second heat exchanger; The thermal management system further comprises: a hydraulic circuit, comprising the second heat exchanger, a hydraulic oil tank and a hydraulic pump, wherein the hydraulic circuit is connected to the motor circuit via the second heat exchanger, wherein the hydraulic pump is mechanically connected to the hydraulic pump motor; The controller is electrically connected to the hydraulic circuit and is further configured to: when there is a need to heat the hydraulic oil in the hydraulic circuit, control the hydraulic pump motor to start to drive the hydraulic pump to work, so that the hydraulic oil in the hydraulic circuit flows to the second heat exchanger, and heats the hydraulic oil by exchanging heat with the motor circuit coolant.

8. The thermal management system for a pure electric crawler crane according to claim 7, characterized in that: The hydraulic circuit further comprises a control valve and a hydraulic cylinder, wherein the control valve is connected to the hydraulic cylinder; The controller is further configured to: when there is a need to dissipate heat of the hydraulic oil in the hydraulic circuit, control the hydraulic oil in the hydraulic oil tank to flow into the second heat exchanger through the hydraulic pump, and control the hydraulic oil in the hydraulic oil tank to flow through the hydraulic pump, the control valve and the hydraulic cylinder in sequence and then flow into the second heat exchanger to exchange heat with the coolant in the motor circuit.

9. The thermal management system for a pure electric crawler crane according to claim 7, characterized in that: The battery circuit further includes a first expansion tank; The controller is further configured to: when there is a need to heat the power battery, control the coolant in the motor circuit to flow into the power battery through the first water pump and the first three-way valve, and then flow through the first expansion tank, the second water pump, and the second three-way valve in sequence to flow into the hydraulic pump motor, and then flow into the first water pump through the fourth three-way valve to heat the power battery.

10. The thermal management system for a pure electric crawler crane according to claim 2, characterized in that: The battery circuit further includes a first expansion tank, and the motor circuit further includes a radiator, a second expansion tank, and a fifth three-way valve, wherein three ends of the fifth three-way valve are respectively connected to the radiator, the first water pump, and the hydraulic pump motor; In the case where both the hydraulic pump motor and the power battery have heat dissipation requirements, the controller is further configured to: determining a coolant temperature in the motor circuit; The first three-way valve, the second three-way valve, and the fifth three-way valve are controlled according to the temperature of the coolant in the motor circuit.

11. The thermal management system for a pure electric crawler crane according to claim 10, characterized in that: When the coolant temperature in the motor circuit is less than or equal to a first temperature threshold of the power battery, the controller is further configured to: controlling the first three-way valve to connect to the first water pump and the battery circuit and to disconnect from the hydraulic pump motor; controlling the second three-way valve to connect to the second water pump and the motor circuit and disconnect from the power battery; The fifth three-way valve is controlled to be connected to the hydraulic pump motor and the radiator and disconnected from the first water pump, so as to control the coolant in the motor circuit to flow into the radiator after passing through the first water pump, the first three-way valve, the power battery, the first expansion tank, the second water pump, the hydraulic pump motor, and the fifth three-way valve in sequence, and then flow into the first water pump through the second expansion tank to dissipate heat for the power battery and the hydraulic pump motor.

12. The thermal management system for a pure electric crawler crane according to claim 11, characterized in that: When the coolant temperature in the motor circuit is greater than the first temperature threshold, the controller is further configured to: controlling the first three-way valve to connect to the first water pump and the hydraulic pump motor and to disconnect from the battery circuit; controlling the fifth three-way valve to be connected to the hydraulic pump motor and the radiator and disconnected from the first water pump, so as to control the coolant in the motor circuit to flow into the radiator after passing through the first water pump, the first three-way valve, the hydraulic pump motor, and the fifth three-way valve in sequence, and then flow into the first water pump through the second expansion tank, so as to dissipate heat from the hydraulic pump motor; The second three-way valve is controlled to be connected to the second water pump and the power battery and disconnected from the motor circuit, so that the coolant in the battery circuit flows into the first heat exchanger after passing through the second water pump, the second three-way valve, and the power battery in sequence, so that the coolant in the battery circuit exchanges heat with the refrigerant in the air-conditioning circuit through the first heat exchanger and flows into the second water pump through the first expansion tank, so as to reduce the temperature of the coolant and achieve heat dissipation of the power battery.

13. The thermal management system for a pure electric crawler crane according to claim 12, characterized in that: When the coolant temperature in the motor circuit is greater than the first temperature threshold and there is no heat dissipation demand or heating demand in the cab, the controller is further configured to: The third three-way valve is controlled to be connected to the compressor and the air-conditioning radiator, and disconnected from the condenser, so that the refrigerant in the air-conditioning circuit flows into the air-conditioning radiator through the compressor, and flows into the first heat exchanger through the one-way valve and the first expansion valve in sequence to dissipate heat for the power battery, and the refrigerant after heat exchange is controlled to flow into the compressor through the gas-liquid separator.

14. The thermal management system for a pure electric crawler crane according to claim 12, characterized in that: When the coolant temperature in the motor circuit is greater than the first temperature threshold and the cab has a heat dissipation demand, the controller is further configured to: The third three-way valve is controlled to be connected to the compressor and the air-conditioning radiator, and disconnected from the condenser, so that the refrigerant in the air-conditioning circuit flows into the air-conditioning radiator through the compressor, and flows into the first heat exchanger through the one-way valve, the second expansion valve, and the evaporator in sequence to dissipate heat to the power battery and the cab, and the refrigerant after heat exchange is controlled to flow into the compressor through the first expansion valve, the second expansion valve, the evaporator, and the gas-liquid separator.

15. The thermal management system for a pure electric crawler crane according to claim 12, characterized in that: When the coolant temperature in the motor circuit is greater than the first temperature threshold, and the difference between the indoor temperature of the cab and the second temperature threshold is greater than or equal to a preset difference, the controller is further configured to: The third three-way valve is controlled to be connected to the compressor and the condenser, and disconnected from the air-conditioning radiator, so that the refrigerant in the air-conditioning circuit flows into the condenser through the compressor, and flows into the first heat exchanger through the first expansion valve to exchange heat with the coolant of the power battery, and the refrigerant after heat exchange is controlled to flow into the compressor through the gas-liquid separator.

16. The thermal management system for a pure electric crawler crane according to claim 15, characterized in that: When the coolant temperature in the motor circuit is greater than the first temperature threshold, and the difference between the indoor temperature and the second temperature threshold is less than the preset difference, the controller is further configured to: The third three-way valve is controlled to be connected to the compressor, the condenser and the air-conditioning radiator, so that the refrigerant in the air-conditioning circuit passes through the compressor and the third three-way valve and flows through the air-conditioning radiator and the condenser respectively, and flows through the first expansion valve, the first heat exchanger and the gas-liquid separator in sequence before flowing into the compressor.

17. The thermal management system for a pure electric crawler crane according to claim 10, characterized in that: The radiator includes a fan; The controller is further configured to control the fan to start when the hydraulic pump motor has a heat dissipation requirement, so as to reduce the temperature of the coolant in the motor circuit.

18. A pure electric crawler crane, characterized in that: The invention comprises a thermal management system for a pure electric crawler crane according to any one of claims 1 to 17.

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