Energy management system, power plant and control method of energy management system

Abstract

The application discloses an energy management system, a power device and a control method of the energy management system. The energy management system comprises a braking resistor and a thermal management unit. The braking resistor is electrically connected with a driving unit of the power device to form a braking energy loop, and is electrically connected with a battery of the power device to form an electric heating loop. The thermal management unit is used for heating the battery by heat generated by the braking resistor. According to the energy management system provided by the application, the braking energy can be recycled, the temperature of the battery can be adjusted, and the braking energy can be fully utilized. The braking resistor can be powered by the battery, the braking resistor generates heat, and the heat is transmitted through the thermal management unit to heat the battery, so that the working performance of the battery is ensured, and the overall structure is simple, and the cost can be saved.

Description

Technical Field

[0001] This invention relates to the field of braking energy recovery technology, and in particular to an energy management system, power equipment, and a control method for the energy management system. Background Technology

[0002] Power batteries in power equipment typically have a defined operating temperature range. Excessively low temperatures can reduce battery discharge efficiency. For example, in vehicles (such as electric vehicles), low battery temperatures can decrease discharge efficiency, affecting the vehicle's driving range. Therefore, to ensure battery performance, it's necessary to maintain the battery within its normal operating temperature range. Related technologies incorporate regenerative braking systems to recover and utilize the braking energy generated during braking, converting it into heat to heat the battery. However, this requires a dedicated heating system (such as a PTC heater) to heat the battery system, complicating the overall structure and increasing costs. Summary of the Invention

[0003] This invention proposes an energy management system, a power equipment, and a control method for the energy management system. This system can realize both braking energy recovery and battery temperature regulation, thus making full use of braking energy. Furthermore, the battery can supply power to the braking resistor, which generates heat and transfers the heat through a thermal management unit to heat the battery, thereby ensuring the battery's performance. The overall structure is simple and can save costs.

[0004] In a first aspect, embodiments of the present invention provide an energy management system for a power device, characterized in that it includes: a braking resistor, the braking resistor being adapted to be electrically connected to a drive unit of the power device to form a braking energy circuit, the braking resistor being adapted to be electrically connected to a battery of the power device to form an electric heating circuit; and a thermal management unit, the thermal management unit being used to heat the battery with the heat generated by the braking resistor.

[0005] In the above technical solution, when the power equipment is in a braking state, the braking energy generated by the drive unit supplies power to the braking resistor through the braking energy circuit. The braking resistor heats up and transfers the heat through the thermal management unit to heat the battery, thereby making full use of the braking energy. When the power equipment is in a non-braking state, the battery can directly supply power to the braking resistor through the electric heating circuit. The braking resistor generates heat when energized and transfers the heat through the thermal management unit, which can regulate the battery temperature and ensure the battery's working performance. This results in a simple overall structure and cost savings.

[0006] In some embodiments, the thermal management unit includes a battery thermal management module and a resistance heat exchange module. The battery thermal management module and the resistance heat exchange module are connected to form a thermal management loop for the flow of heat exchange medium. The battery thermal management module is used to regulate the temperature of the battery. The resistance heat exchange module is thermally connected to or in thermal contact with the braking resistor.

[0007] In the above technical solution, the heat generated by the braking resistor can be transferred to the resistance heat exchange module through thermal connection or thermal contact with the resistance heat exchange module. The thermal management module and the resistance heat exchange module are connected to form a thermal management loop. The resistance heat exchange module can transfer heat to the battery thermal management module through the thermal management loop. The battery thermal management module can transfer heat to the battery to regulate the battery temperature and ensure the battery's working performance.

[0008] In some embodiments, when the power device is in a braking state, the braking energy circuit operates and the thermal management unit is controlled according to the temperature of the battery.

[0009] In the above technical solution, when the power equipment is in a braking state, the braking energy circuit works to recover and utilize the braking energy; and by controlling the operation of the thermal management unit according to the battery temperature, it is possible to choose whether to use the braking energy to heat the battery, so as to ensure that the battery is in a suitable temperature range and to ensure the battery's working performance.

[0010] In some embodiments, controlling the thermal management unit according to the temperature of the battery includes: the thermal management unit operating when the temperature of the battery is lower than a first preset temperature; and the thermal management unit not operating when the temperature of the battery is greater than or equal to the first preset temperature.

[0011] In the above technical solution, by controlling the thermal management unit according to the battery temperature, when the battery temperature is lower than the preset temperature, the braking energy circuit and the thermal management unit work to use the braking energy to heat the battery. This can make full use of the braking energy and adjust the battery temperature to a suitable operating temperature range, so that the battery can work normally and thus ensure the battery's performance. In addition, when the battery temperature is greater than or equal to the first preset temperature, the thermal management unit does not work and does not heat the battery, so as to avoid the battery being overheated and affecting its performance.

[0012] In some embodiments, when the temperature of the battery is lower than the first preset temperature, the electric heating circuit is controlled according to the temperature of the battery or the magnitude of the braking energy.

[0013] In the above technical solution, by controlling the electric heating circuit according to the battery temperature or the magnitude of braking energy, the battery can be heated using braking energy, and the option to activate the electric heating circuit to further heat the battery can be selected. This further ensures that the battery temperature is adjusted to a suitable operating temperature range, thereby further guaranteeing the battery's performance.

[0014] In some embodiments, controlling the electric heating circuit according to the temperature of the battery or the magnitude of the braking energy includes: the electric heating circuit operating when the temperature of the battery is less than a second preset temperature or the braking energy is less than a first preset energy value, wherein the second preset temperature is less than the first preset temperature.

[0015] In the above technical solution, the electric heating circuit operates when the battery temperature is lower than the second preset temperature or the braking energy is lower than the first preset energy value. This not only makes full use of the braking energy to heat the battery, but also allows the battery temperature to be further adjusted to a suitable operating temperature range when the battery temperature is low or the braking energy is low and the braking energy alone cannot meet the battery heating requirements, thereby further ensuring the battery's working performance.

[0016] In some embodiments, when the power device is not in a braking state, the electric heating circuit is controlled according to the temperature of the battery; wherein, when the temperature of the battery is less than a first preset temperature, the electric heating circuit and the thermal management unit operate, and the battery supplies power to the braking resistor to heat the battery; when the temperature of the battery is greater than or equal to the first preset temperature, the electric heating circuit and the thermal management unit do not operate.

[0017] In the above technical solution, when the power equipment is not in a braking state, the heating requirements of the battery can be met by controlling the electric heating circuit according to the battery temperature, thereby ensuring that the battery can be kept within the normal operating temperature range and ensuring the battery's working performance.

[0018] In some embodiments, the battery includes multiple battery branches connected in parallel, and when the electric heating circuit is working, the battery branch with the largest amount of power preferentially supplies power to the braking resistor.

[0019] In the above technical solution, prioritizing the supply of power to the braking resistor by the battery branch with the largest capacity not only regulates the battery temperature, but also allows the battery branch with the largest capacity to discharge through the braking resistor, which helps to achieve balance among multiple battery branches, improves the consistency of each battery branch, and ensures the battery's service life.

[0020] In some embodiments, the battery includes multiple battery branches connected in parallel, and each battery branch is connected in series with a control switch. The control switch is controlled according to the relationship between the charge levels of all the battery branches, so that the battery branch with the largest charge level is preferentially connected to the braking resistor to form the electric heating circuit.

[0021] In the above technical solution, by controlling the control switch according to the relationship between the charge levels of all battery branches, the battery branch with higher charge can form an electric heating circuit with the braking resistor to discharge the battery branch with higher charge. This helps to balance the battery branches, improve battery consistency, reduce battery maintenance costs, and ensure battery life.

[0022] In some embodiments, the battery branch includes at least one battery cell, each battery branch is connected in series with two control switches, and all the battery cells of each battery branch are connected in series between the two control switches.

[0023] In the above technical solution, two control switches are connected in series in each battery branch, and all battery cells in each battery branch are connected in series between the two control switches. If one of the control switches in a battery branch fails, the other control switch can still work normally, which can improve the reliability of the control of the battery branch and thus realize the balance adjustment of the power of each battery branch.

[0024] In some embodiments, the battery is adapted to be electrically connected to the drive unit to form a battery charging and discharging circuit.

[0025] In the above technical solution, the battery is electrically connected to the drive unit to form a battery charging and discharging circuit. The battery can supply power to the drive unit through the battery charging and discharging circuit. The braking energy generated when the drive unit of the power equipment brakes can charge the battery through the battery charging and discharging circuit, so as to make full use of the braking energy.

[0026] In some embodiments, when the power device is in a braking state, the braking energy circuit operates preferentially, and the driving unit preferentially uses the braking energy generated to heat the battery.

[0027] In the above technical solution, when the power equipment is in a braking state, the braking energy circuit works first, and the driving unit uses the braking energy generated to heat the battery first, which can regulate the battery temperature and ensure the battery's working performance. On the other hand, by absorbing a part of the braking energy through the braking resistor, the efficiency of braking energy recovery can be improved, and the problem of battery damage caused by the braking energy still charging the battery when the battery has too much remaining charge can be avoided.

[0028] In some embodiments, when the power device is in a braking state, the battery charging and discharging circuit is controlled according to the remaining charge of the battery or the amount of braking energy generated by the drive unit.

[0029] In the above technical solution, when the power equipment is in a braking state, the battery charging and discharging circuit is controlled according to the remaining battery charge. When the battery charging and discharging circuit is working, the braking energy can charge the battery, fully recovering and utilizing the braking energy, which helps to increase the battery charge. When the remaining battery charge is too high, the problem of battery damage caused by the braking energy still charging the battery can be avoided. By controlling the battery charging and discharging circuit according to the amount of braking energy generated by the drive unit, the energy utilization method can be selectively determined as needed.

[0030] In some embodiments, controlling the battery charging and discharging circuit according to the remaining charge of the battery includes: when the remaining charge of the battery is less than a preset charge, the battery charging and discharging circuit operates, and the driving unit uses the braking energy generated to charge the battery.

[0031] In the above technical solution, the braking energy generated by the drive unit is used to charge the battery to increase the battery's capacity. When the power unit is a vehicle, the vehicle's driving range can be increased.

[0032] In some embodiments, the battery includes multiple battery branches connected in parallel, and the drive unit preferentially charges the battery branch with the lowest charge using the braking energy generated.

[0033] In the above technical solution, the driving unit prioritizes charging the battery branch with the lowest charge by using the generated braking energy, which helps to achieve balance among multiple battery branches, improve the consistency of each battery branch, and ensure the service life of the battery.

[0034] In some embodiments, the energy management system of the power equipment further includes a cooling fan for dissipating heat from the braking resistor; controlling the battery charging and discharging circuit according to the remaining charge of the battery includes: when the remaining charge of the battery is greater than or equal to a preset charge, the battery charging and discharging circuit does not operate and the cooling fan operates.

[0035] In the above technical solution, the operation of the cooling fan, which dissipates heat from the braking resistor, can help the braking resistor consume braking energy, resulting in better heat dissipation. It can also prevent the braking resistor from overheating, which could lead to excessively high ambient temperatures and affect the service life of other surrounding components.

[0036] In some embodiments, controlling the battery charging and discharging circuit according to the magnitude of the braking energy generated by the driving unit includes: when the braking energy is less than a second preset energy value, the braking energy circuit operates and the battery charging and discharging circuit does not operate; when the braking energy is greater than or equal to the second preset energy value, both the braking energy circuit and the battery charging and discharging circuit operate.

[0037] In the above technical solution, when the braking energy is less than the second preset energy value, the braking energy circuit operates while the battery charging and discharging circuit does not operate. When the braking energy is greater than or equal to the second preset energy value, both the braking energy circuit and the battery charging and discharging circuit operate. The braking energy can be converted into heat energy to heat the battery to ensure the battery's working performance, and it can also charge the battery to increase the battery's capacity, thus achieving full recovery and utilization of braking energy. Furthermore, when the braking energy is low, it is preferentially used to heat the battery, while when the braking energy is high, it can both heat and charge the battery, thus achieving full utilization of braking energy while prioritizing battery heating to ensure the battery's working performance.

[0038] In some embodiments, the energy management system of the power equipment further includes a cooling fan for dissipating heat from the braking resistor.

[0039] In the above technical solution, the use of a cooling fan to dissipate heat from the braking resistor can help the braking resistor consume the braking energy generated by the drive unit, resulting in better heat dissipation and preventing the braking resistor from overheating and affecting the operation of other surrounding components.

[0040] In some embodiments, the resistance value of the braking resistor is adjustable.

[0041] In the above technical solution, the adjustable resistance value of the braking resistor can meet the heating requirements of the battery and ensure the recovery rate of braking energy.

[0042] Secondly, embodiments of the present invention also propose a power device, including the aforementioned energy management system. Thus, by employing the aforementioned energy management system for the power device, both braking energy recovery and battery temperature regulation can be achieved, allowing for full utilization of braking energy. Furthermore, when the power device is not braking, the battery can supply power to the braking resistor, which heats up and transfers heat through the thermal management unit, thereby heating the battery and ensuring its performance. Moreover, the overall structure is simple, saving costs.

[0043] Thirdly, embodiments of the present invention also provide a control method for an energy management system of a power device. The energy management system includes a braking resistor and a thermal management unit. The braking resistor is adapted to be electrically connected to a drive unit of the power device to form a braking energy circuit, and the braking resistor is adapted to be electrically connected to a battery of the power device to form an electric heating circuit. The thermal management unit is used to heat the battery with the heat generated by the braking resistor. The control method includes: determining whether the power device is in a braking state; if the power device is in a braking state, determining whether the temperature of the battery is lower than a first preset temperature; if the temperature of the battery is lower than the first preset temperature, the braking energy circuit operates and the thermal management unit operates.

[0044] In the above technical solution, when the power equipment is in a braking state, the braking energy generated by the drive unit supplies power to the braking resistor through the braking energy circuit. The braking resistor heats up and transfers the heat through the thermal management unit to heat the battery, thus making full use of the braking energy. Alternatively, the battery can directly supply power to the braking resistor through the electric heating circuit. The braking resistor generates heat when energized and transfers the heat through the thermal management unit. The thermal management unit uses the heat generated by the braking resistor to heat the battery, thereby regulating the battery temperature and ensuring the battery's performance. This makes the overall structure simpler and saves costs.

[0045] In some embodiments, if the temperature of the battery is lower than the first preset temperature, the braking energy circuit operates and the thermal management unit operates, including: determining whether the temperature of the battery is lower than a second preset temperature, wherein the second preset temperature is lower than the first preset temperature; if the temperature of the battery is lower than the second preset temperature, controlling the electric heating circuit to operate; if the temperature of the battery is greater than or equal to the second preset temperature, controlling the electric heating circuit not to operate.

[0046] In the above technical solution, when the battery temperature is lower than the second preset temperature, the electric heating circuit is controlled to work to heat the battery. When the battery temperature is low or the braking energy is small and the braking energy alone cannot meet the battery heating requirements, the electric heating circuit can further adjust the battery temperature to a suitable operating temperature range to further ensure the battery's working performance. When the battery temperature is greater than or equal to the second preset temperature, the electric heating circuit is controlled not to work, which can prevent the battery temperature from overheating, thereby achieving full utilization of the braking energy and adjusting the battery temperature to a suitable operating temperature range to ensure the battery's working performance.

[0047] In some embodiments, if the temperature of the battery is lower than the first preset temperature, the braking energy circuit operates and the thermal management unit operates, including: determining whether the braking energy is lower than a first preset energy value; if the braking energy is lower than the first preset energy value, controlling the electric heating circuit to operate; if the braking energy is greater than or equal to the first preset energy value, controlling the electric heating circuit not to operate.

[0048] In the above technical solution, when the power equipment is in a braking state and the battery temperature is low, braking energy can be used to heat the battery to increase its temperature. Furthermore, by controlling the operation of the electric heating circuit based on the magnitude of the braking energy, when the braking energy is too low to meet the battery's heating requirements, the electric heating circuit can be activated to heat the battery, ensuring its temperature is within the operating temperature range. Conversely, when the braking energy is high enough to meet the battery's heating requirements, the electric heating circuit can be deactivated. This ensures the battery temperature while saving energy. This approach fully utilizes braking energy for battery heating, and when the braking energy is low and insufficient to meet the battery's heating needs, the electric heating circuit can further regulate the battery temperature to a suitable operating temperature range, thus further guaranteeing the battery's performance.

[0049] In some embodiments, the battery is adapted to be electrically connected to the drive unit to form a battery charging and discharging circuit. If the power device is in a braking state, it is determined whether the remaining charge of the battery is less than a preset charge. If the remaining charge of the battery is less than the preset charge, the battery charging and discharging circuit is controlled to work, and the drive unit uses the generated braking energy to charge the battery. If the remaining charge of the battery is greater than or equal to the preset charge, the battery charging and discharging circuit is controlled not to work.

[0050] In the above technical solution, the battery charging and discharging circuit is controlled to work when the remaining battery power is less than the preset power; when the remaining battery power is greater than or equal to the preset power, the battery charging and discharging circuit is controlled to not work, and the driving unit uses the braking energy generated to charge the battery. This can recover and utilize braking energy to increase the battery power. Furthermore, by controlling the battery charging and discharging circuit based on the remaining battery power, it is possible to determine whether to charge the battery based on the remaining battery power, which can prevent the battery from being damaged by overcharging.

[0051] In some embodiments, the battery includes multiple battery branches connected in parallel, and controlling the operation of the battery charging and discharging circuit includes: the drive unit preferentially charging the battery branch with the lowest charge using the braking energy generated.

[0052] In the above technical solution, the driving unit prioritizes charging the battery branch with the lowest charge by using the generated braking energy, which helps to achieve balance among multiple battery branches, improve the consistency of each battery branch, and ensure the service life of the battery.

[0053] In some embodiments, the energy management system further includes a cooling fan for dissipating heat from the braking resistor. If the remaining charge of the battery is greater than or equal to the preset charge, the battery charging and discharging circuit does not operate and the cooling fan operates.

[0054] In the above technical solution, the operation of the cooling fan, which dissipates heat from the braking resistor, can help the braking resistor consume braking energy, resulting in better heat dissipation. It can also prevent the braking resistor from overheating, which could lead to excessively high ambient temperatures and affect the service life of other surrounding components.

[0055] In some embodiments, determining whether the power device is in a braking state further includes: if the power device is not in a braking state, determining whether the temperature of the battery is lower than the first preset temperature; if the temperature of the battery is lower than the first preset temperature, controlling the electric heating circuit to operate to heat the battery.

[0056] In the above technical solution, when the power equipment is not in a braking state, the heating requirements of the battery can be met by controlling the electric heating circuit according to the battery temperature, thereby ensuring that the battery can be kept within the normal operating temperature range and ensuring the battery's working performance.

[0057] In some embodiments, the battery includes multiple battery branches connected in parallel, and controlling the operation of the electric heating circuit includes: the battery branch with the largest amount of power preferentially supplies power to the braking resistor.

[0058] In the above technical solution, prioritizing the supply of power to the braking resistor by the battery branch with the largest capacity not only regulates the battery temperature, but also allows the battery branch with the largest capacity to discharge through the braking resistor, which helps to achieve balance among multiple battery branches, improves the consistency of each battery branch, and ensures the battery's service life.

[0059] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0060] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0061] Figure 1This is a schematic diagram of the working principle of the energy management system of a power device according to some embodiments of the present invention;

[0062] Figure 2 This is a schematic diagram of the electric heating circuit and the thermal management circuit of an energy management system according to some embodiments of the present invention;

[0063] Figure 3 This is a schematic diagram of the electrical connection between multiple battery branches and a braking resistor in an energy management system according to some embodiments of the present invention.

[0064] Figure 4 This is a schematic diagram of the control flow of a control method for an energy management system according to some embodiments of the present invention.

[0065] Figure label:

[0066] 100. Energy Management System;

[0067] 11. Battery; 110. Battery branch; 111. Battery cell; 13. Circulation pump; 15. Battery thermal management module;

[0068] 21. Drive unit; 220. Braking resistor; 221. First interface; 222. Second interface; 223. Resistance heat exchange module; 224. Water inlet; 225. Water outlet; 23. Cooling fan; 24. Braking energy circuit;

[0069] 3. Battery charging and discharging circuit; 4. Electric heating circuit; 5. Thermal management unit; 6. High voltage box; 61. Control switch; 7. Thermal management circuit. Detailed Implementation

[0070] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0071] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0072] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used in the specification of this application is for the purpose of describing particular embodiments only and is not intended to limit the invention; the terms "comprising" and "having," and any variations thereof, in the specification, claims, and foregoing drawings are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the specification, claims, or foregoing drawings are used to distinguish different objects, not to describe a particular order or hierarchy.

[0073] In this invention, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments.

[0074] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "attachment" 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 direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0075] In this invention, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this invention, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0076] In the embodiments of the present invention, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of the present invention shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on the present invention.

[0077] In this invention, "multiple" refers to two or more (including two).

[0078] In this invention, battery 11 refers to a device that can convert chemical energy into electrical energy. For example, battery 11 can refer to a single physical module comprising one or more battery cells to provide higher voltage and capacity. When battery 11 comprises multiple battery cells, these cells can be connected in series, parallel, or a combination thereof to directly form a battery unit 111. A combination thereof refers to multiple battery cells being connected in both series and parallel configurations. The battery unit 111 mentioned in this invention can include at least one battery cell, and the battery unit 111 can be a battery module or battery pack, etc.

[0079] In this invention, the battery cell may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, or magnesium-ion batteries, etc., and the embodiments of this invention are not limited to these. The battery cell may be cylindrical, flat, cuboid, or other shapes, etc., and the embodiments of this invention are not limited to these. Battery cells are generally classified into three types according to their packaging method: cylindrical battery cells, square battery cells, and pouch battery cells, and the embodiments of this invention are not limited to these.

[0080] For example, a single battery cell may include a battery casing, electrode assembly, and electrolyte. The battery casing houses the electrode assembly and electrolyte. The electrode assembly consists of a positive electrode, a negative electrode, and a separator. The battery cell primarily functions by the movement of metal ions between the positive and negative electrode plates. The positive electrode includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive current collector, and the uncoated positive current collector protrudes beyond the coated positive current collector, serving as the positive electrode tab. Taking a lithium-ion battery as an example, the material of the positive current collector can be aluminum, and the positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc.

[0081] The negative electrode includes a negative current collector and a negative active material layer. The negative active material layer is coated on the surface of the negative current collector, and the negative current collector without the negative active material layer protrudes from the one with the negative active material layer. The negative current collector without the negative active material layer serves as the negative electrode tab. The material of the negative current collector can be copper, and the negative active material can be carbon or silicon, etc. To ensure that a large current can be passed without melting, there are multiple positive electrode tabs stacked together, and there are multiple negative electrode tabs stacked together.

[0082] The separator can be made of PP (polypropylene) or PE (polyethylene), etc. Furthermore, the electrode assembly can be a wound structure or a stacked structure; the embodiments of the present invention are not limited thereto.

[0083] The battery 11 of the present invention can also be a fuel cell, for example, the battery 11 can be a hydrogen fuel cell.

[0084] Power batteries for power equipment typically have a defined operating temperature range. In cold environments, excessively low battery temperatures can increase internal resistance, reducing usable capacity and decreasing discharge efficiency. Furthermore, low temperatures also tend to decrease charging efficiency, thus affecting the use of the power equipment, such as the driving range of a vehicle. Therefore, to ensure battery performance, it is necessary to maintain the battery within its normal operating temperature range to guarantee efficient charging and discharging.

[0085] During braking, the drive unit of a power device can switch from electric motor mode to generator mode. For example, the power device could be a vehicle (such as an electric car). The vehicle's battery has a normal operating temperature range. To ensure battery performance, the battery needs to be kept within this range to guarantee charging and discharging efficiency and the vehicle's driving range. During braking, the inertia of the wheels causes the drive motor to rotate, switching it from electric motor mode to generator mode to generate braking energy.

[0086] In related technologies, a regenerative braking system is installed in power equipment such as vehicles. When the power equipment is braking, the regenerative braking system operates to recover and utilize the braking energy generated during braking. This braking energy can be converted into heat energy and transferred to the battery to heat it. However, when the power equipment is not braking, a dedicated heating system (such as a PTC) is still required to heat the battery system. This makes the overall structure more complex and increases costs.

[0087] Based on this, in order to recover braking energy, regulate battery temperature, simplify structure and reduce cost, the applicant has conducted in-depth research and proposed an energy management system 100 for a power device. The energy management system 100 includes a braking resistor 220 and a thermal management unit 5. The braking resistor 220 is adapted to be electrically connected to the drive unit 21 of the power device to form a braking energy circuit 24, and the braking resistor 220 is adapted to be electrically connected to the battery 11 of the power device to form an electric heating circuit 4. The thermal management unit 5 is used to heat the battery 11 with the heat generated by the braking resistor 220.

[0088] In the technical solution of the present invention, the braking resistor 220 is electrically connected to the drive unit 21 of the power equipment to form a braking energy circuit 24. The braking energy generated by the drive unit 21 can supply power to the braking resistor 220. The braking resistor 220 is electrically connected to the battery 11 of the power equipment to form an electric heating circuit 4. The braking resistor 220 generates heat when energized. The thermal management unit 5 is used to heat the battery 11 with the heat generated by the braking resistor 220 to regulate the temperature of the battery 11, thereby ensuring the working performance of the battery 11.

[0089] When the power equipment (e.g., a vehicle) is in a braking state, the braking energy generated by the drive unit 21 supplies power to the braking resistor 220 through the braking energy circuit 24. The braking resistor 220 generates heat and transfers the heat through the thermal management unit 5, thereby heating the battery 11 and making full use of the braking energy. The battery 11 can directly supply power to the braking resistor 220 through the electric heating circuit 4. The braking resistor 220 generates heat when energized and transfers the heat through the thermal management unit 5. The thermal management unit 5 uses the heat generated by the braking resistor 220 to heat the battery, thereby regulating the temperature of the battery 11 and ensuring the working performance of the battery 11. This makes the overall structure simpler and reduces costs.

[0090] This invention provides a power device using battery 11 as a power source. The power device can be, but is not limited to, vehicles, ships, spacecraft, etc. For example, the power device can be a vehicle, which can be, but is not limited to, electric vehicles, hydrogen fuel cell vehicles, etc. Electric vehicles can include trucks, construction vehicles, cars, etc. When battery 11 is used in a vehicle, battery 11 can be located at the bottom, front, or rear of the vehicle.

[0091] The energy management system 100 of the power equipment according to an embodiment of the present invention is described below with reference to the accompanying drawings.

[0092] Reference Figure 1 and Figure 2 In a first aspect, embodiments of the present invention provide an energy management system 100 for a power device, comprising: a braking resistor 220 and a thermal management unit 5. The braking resistor 220 is adapted to be electrically connected to a drive unit 21 of the power device to form a braking energy circuit 24, and the braking resistor 220 is adapted to be electrically connected to a battery 11 of the power device to form an electric heating circuit 4. The thermal management unit 5 is used to heat the battery 11 with the heat generated by the braking resistor 220.

[0093] When the power equipment brakes, the drive unit 21 changes from motor mode to generator mode. The drive unit 21 can convert part of the kinetic energy into electrical energy, generating a force opposite to that when the power equipment is driven, thus braking the power equipment.

[0094] For example, the power unit can be a vehicle, and the drive unit 21 can include a drive motor and motor control components. The drive motor can drive the vehicle's wheels to rotate, thereby driving the vehicle. When the vehicle brakes, the battery 11 stops supplying power to the drive unit 21, but the vehicle's wheels continue to rotate. The drive motor of the drive unit 21 can rotate under the drive of the wheels. At this time, the drive motor operates in a generator state, converting part of the vehicle's kinetic energy into electrical energy. Simultaneously, it applies a feedback torque to the drive shaft, generating a force opposite to the vehicle's driving motion, thus braking the vehicle. Therefore, when the vehicle brakes, the drive motor switches from electric motor mode to generator mode and generates braking energy. The braking energy can include the electrical energy generated by the drive motor after switching from electric motor mode to generator mode.

[0095] The drive unit 21 is electrically connected to the braking resistor 220 to form a braking energy circuit 24. The braking energy generated by the drive unit 21 can supply power to the braking resistor 220 through the braking energy circuit 24. The braking resistor 220 generates heat when energized. The thermal management unit 5 can transfer the energy to the battery to regulate the temperature of the battery 11, thereby using the braking energy to heat the battery 11.

[0096] Battery 11 is electrically connected to braking resistor 220 to form electric heating circuit 4. Battery 11 can supply power to braking resistor 220, which generates heat. Thermal management unit 5 can transfer energy to battery 11 to regulate its temperature. Thus, the electrical energy of battery 11 can be converted into heat energy through braking resistor 220 to heat battery 11. For example, when braking energy cannot meet the heating requirements of battery 11 or when the power equipment is not in a braking state, electric heating circuit 4 can be used to heat battery 11.

[0097] The way in which the battery 11 is electrically connected to the braking resistor 220 to form the electric heating circuit 4 can include the following example: the braking resistor 220 has a first interface 221 and a second interface 222, the first interface 221 of the braking resistor 220 is electrically connected to the positive terminal of the battery 11, and the second interface 222 of the braking resistor 220 is electrically connected to the negative terminal of the battery 11, so that the battery 11 is electrically connected to the braking resistor 220 and the battery 11 can supply power to the braking resistor 220.

[0098] For example, when the battery 11 is at a low temperature and the power equipment is braking, the braking energy circuit 24 is activated, and the braking energy generated by the drive unit 21 supplies power to the braking resistor 220 through the braking energy circuit 24; when the battery 11 is at a low temperature and the power equipment is not braking, the battery 11 can supply power to the braking resistor 220 through button or program control.

[0099] When the braking energy circuit 24 is working, it can be understood that the braking energy generated by the drive unit 21 supplies power to the braking resistor 220, causing the braking resistor 220 to heat up. When the electric heating circuit 4 is working, it can be understood that the battery 11 supplies power to the braking resistor 220, causing the braking resistor 220 to heat up. When the electric heating circuit 4 is not working, it can be understood that the battery 11 does not supply power to the braking resistor 220.

[0100] When the power equipment is in braking mode, the braking energy generated by the drive unit 21 can supply power to the braking resistor 220, causing the braking resistor 220 to heat up. This heat is then transferred to the battery 11 via the thermal management unit 5 to heat the battery. When the braking energy is insufficient to meet the heating requirements of the battery 11, the battery 11 can supply power to the braking resistor 220, and the heat generated by the braking resistor 220 can be transferred to the battery 11 via the thermal management unit to heat the battery. When the power equipment is not in braking mode, the battery 11 can supply power to the braking resistor 220, causing the braking resistor 220 to generate heat, which can then be transferred to the battery 11 via the thermal management unit 5 to heat the battery.

[0101] In the above technical solution, when the power equipment is in a braking state, the braking energy generated by the drive unit 21 supplies power to the braking resistor 220 through the braking energy circuit 24. The braking resistor 220 heats up and transfers the heat through the thermal management unit 5, thereby heating the battery 11 and making full use of the braking energy. The battery 11 can directly supply power to the braking resistor 220 through the electric heating circuit 4. The braking resistor 220 generates heat when energized and transfers the heat through the thermal management unit 5. The thermal management unit 5 uses the heat generated by the braking resistor 220 to heat the battery, thereby regulating the temperature of the battery 11 and ensuring the working performance of the battery 11. This makes the overall structure simpler and reduces costs.

[0102] In addition, since the power equipment is a vehicle, the excessive feedback torque applied to the drive shaft during emergency braking can easily cause excessive tire wear. By recovering some braking energy through the braking resistor 220, the braking purpose can be achieved, and tire wear can be reduced, thus ensuring the service life of the tires.

[0103] In some embodiments, refer to Figure 2 The thermal management unit 5 includes a battery thermal management module 15 and a resistance heat exchange module 223. The battery thermal management module 15 and the resistance heat exchange module 223 are connected to form a thermal management loop 7 for the flow of heat exchange medium. The battery thermal management module 15 is used to regulate the temperature of the battery 11. The resistance heat exchange module 223 is thermally connected or in thermal contact with the braking resistor 220.

[0104] The resistance heat exchange module 223 is thermally connected or in thermal contact with the braking resistor 220. For example, the resistance heat exchange module 223 is connected or in contact with the braking resistor 220. When the resistance heat exchange module 223 is connected to the braking resistor 220, the resistance heat exchange module 223 can be welded to the braking resistor 220, or the resistance heat exchange module 223 can be connected to the braking resistor 220 through thermally conductive connection or thermally conductive contact. The resistance heat exchange module 223 can exchange heat with the braking resistor 220, and the braking resistor 220 can conduct heat to the resistance heat exchange module 223.

[0105] The resistance heat exchange module 223 is connected to the battery thermal management module 15 to form a thermal management circuit 7. The thermal management circuit 7 allows for the flow of heat exchange medium. When the thermal management circuit 7 is working, after the resistance heat exchange module 223 exchanges heat with the braking resistor 220, the resistance heat exchange module 223 can transfer heat to the battery thermal management module 15 through the thermal management circuit 7, allowing the battery thermal management module 15 to heat the battery 11. When the thermal management circuit 7 is not working, the heat from the braking resistor 220 will not be transferred to the battery thermal management module 15, and the battery 11 will not be heated.

[0106] For example, the resistance heat exchange module 223 may include a heat exchange tube, within which a heat exchange medium flows. The heat exchange medium may include water. The heat exchange medium within the resistance heat exchange module 223 can exchange heat with the braking resistor 220. The battery thermal management module 15 may have a heat exchange channel, within which a heat exchange medium flows. The heat exchange medium can exchange heat with the battery 11 to regulate the temperature of the battery 11. The outlet 225 of the resistance heat exchange module 223 is connected to the inlet of the heat exchange channel, and the inlet 224 of the resistance heat exchange module 223 is connected to the outlet of the heat exchange channel. The heat exchange medium can circulate between the resistance heat exchange module 223 and the battery thermal management module 15. A circulation pump 13 can be connected in series on the thermal management circuit 7. The circulation pump 13 can drive the heat exchange medium in the resistance heat exchange module 223 to flow into the battery thermal management module 15 through the outlet 225. The heat exchange medium can exchange heat with the battery 11, thereby regulating the temperature of the battery 11. After exchanging heat with the battery 11, the heat exchange medium flows back to the resistance heat exchange module 223 from the inlet 224 and continues to exchange heat with the braking resistor 220, continuing to circulate.

[0107] For example, when the battery 11 is at a low temperature and the power equipment is braking, the braking energy circuit 24 operates, and the braking energy generated by the drive unit 21 supplies power to the braking resistor 220 through the braking energy circuit 24. When the battery 11 is at a low temperature and the power equipment is not braking, the battery 11 can supply power to the braking resistor 220 via a button or program control. In both of these cases, the braking resistor 220 is energized and heats up, exchanging heat with the heat exchange medium. Driven by the circulating pump 13, the heat exchange medium circulates from the resistance heat exchange module 223 to the battery thermal management module 15, allowing the battery thermal management module 15 to exchange heat with the battery 11, thereby heating the battery 11.

[0108] When the thermal management circuit 7 is working, it can be understood that the heat exchange medium within the thermal management circuit 7 is circulating, for example, the circulating pump 13 is working; when the thermal management circuit 7 is not working, it can be understood that the heat exchange medium within the thermal management circuit 7 is not flowing, for example, the circulating pump 13 stops working.

[0109] In the above technical solution, the heat generated by the braking resistor 220 can be transferred to the heat exchange module 223 through the thermally conductive connection or thermally conductive contact between the resistance heat exchange module 223 and the resistance heat exchange module 223; the battery thermal management module 15 and the resistance heat exchange module 223 are connected to form a thermal management circuit 7, and the resistance heat exchange module 223 can transfer heat to the battery thermal management module 15 through the thermal management circuit 7, and the battery thermal management module 15 can transfer heat to the battery to regulate the temperature of the battery 11 and ensure the working performance of the battery 11.

[0110] In some embodiments, when the power equipment is in a braking state, the braking energy circuit 24 operates and controls the thermal management unit 5 according to the temperature of the battery 11.

[0111] The temperature of the battery 11 can be detected by a temperature sensor, for example, the battery 11 can be equipped with a temperature sensor to detect the temperature of the battery 11.

[0112] The "thermal management unit 5" can refer to whether the thermal management unit 5 and the battery 11 are thermally conductive or not. For example, the flow of the heat exchange medium in the thermal management circuit 7 can be controlled or stopped. The thermal management unit 5 can be controlled by controlling the circulation pump 13. When the circulation pump 13 is working, the heat exchange medium in the thermal management unit 5 flows; when the circulation pump 13 is stopped, the heat exchange medium in the thermal management unit 5 stops flowing.

[0113] For example, when the vehicle is braking, the braking energy circuit 24 is activated, and the braking energy supplies power to the braking resistor 220. When the temperature sensor detects that the temperature of the battery 11 is greater than or equal to a first preset temperature, the battery 11 does not need to be heated, the thermal management unit 5 does not operate, and the heat exchange medium of the thermal management unit 5 does not flow. At this time, the braking energy can be released through the braking resistor 220.

[0114] For example, when the power equipment is in braking mode, the braking energy circuit 24 is working, and the braking energy supplies power to the braking resistor 220, which generates heat. When the temperature sensor detects that the temperature of the battery 11 is lower than the first preset temperature, the battery 11 needs to be heated. The thermal management unit 5 is working, and the heat exchange medium of the thermal management unit 5 circulates. The heat generated by the braking resistor 220 is transferred to the battery 11 through the thermal management unit 5 to heat the battery 11.

[0115] For example, when the power equipment is in braking mode and the temperature sensor detects that the temperature of the battery 11 is lower than the first preset temperature, and the braking energy generated by the drive unit 21 is small, the braking energy supplies power to the braking resistor 220. The heat generated by the braking resistor 220 is insufficient to raise the temperature of the battery 11 to a suitable temperature range. In this case, the electric heating circuit 4 can be controlled to work, supplying power to the braking resistor 220 through the battery 11. The braking resistor 220 generates heat and transfers the heat to the battery thermal management module 15 through the resistance heat exchange module 223. The battery thermal management module 15 can regulate the temperature of the battery 11.

[0116] In the above technical solution, when the power equipment is in a braking state, the braking energy circuit 24 works to recover and utilize the braking energy; and by controlling the operation of the thermal management unit 5 according to the temperature of the battery 11, it is possible to select whether to use the braking energy to heat the battery 11, so as to ensure that the battery 11 is in a suitable temperature range and to ensure the working performance of the battery 11.

[0117] In some embodiments, controlling the thermal management unit 5 according to the temperature of the battery 11 includes: the thermal management unit 5 operating when the temperature of the battery 11 is lower than a first preset temperature; and the thermal management unit 5 not operating when the temperature of the battery 11 is greater than or equal to the first preset temperature.

[0118] For example, the first preset temperature can be the lowest temperature that ensures that the battery 11 can work normally.

[0119] For example, a temperature sensor can be provided in the battery system to detect the temperature of the battery 11. When the temperature sensor detects that the temperature of the battery 11 is lower than the first preset temperature, the braking energy circuit 24 is activated, the thermal management unit 5 is also activated, the braking energy generated by the drive unit 21 supplies power to the braking resistor 220, the braking resistor 220 heats up and conducts the heat to the resistance heat exchange module 223, the resistance heat exchange module 223 can transfer the heat to the battery thermal management module 15 through the thermal management unit 5, and the battery thermal management module 15 can heat the battery 11.

[0120] For example, when the temperature sensor detects that the temperature of the battery 11 is greater than or equal to the first preset temperature, the braking energy circuit 24 is activated, the thermal management unit 5 is deactivated, the heat exchange medium in the thermal management unit 5 is not circulated, the braking energy generated by the drive unit 21 supplies power to the braking resistor 220, and the braking resistor 220 generates heat, which can consume the braking energy; when the remaining power of the battery 11 is low, the braking energy can also be used to charge the battery 11.

[0121] When thermal management unit 5 is working, it can be understood that thermal management unit 5 transfers the heat generated by braking resistor 220 to the battery; when thermal management unit 5 is not working, it can be understood that thermal management unit 5 does not transfer the heat generated by braking resistor 220 to the battery.

[0122] In the above technical solution, by controlling the thermal management unit 5 according to the temperature of the battery 11, when the temperature of the battery 11 is lower than the preset temperature, the braking energy circuit 24 and the thermal management unit 5 work to use the braking energy to heat the battery 11. This can make full use of the braking energy and adjust the temperature of the battery 11 to a suitable operating temperature range, so that the battery 11 can work normally and thus ensure the working performance of the battery 11. In addition, when the temperature of the battery 11 is greater than or equal to the first preset temperature, the thermal management unit 5 does not work and does not heat the battery 11, so as to avoid the battery 11 being overheated and affecting its working performance.

[0123] In some embodiments, when the temperature of the battery 11 is lower than a first preset temperature, the electric heating circuit 4 is controlled according to the temperature of the battery 11 or the magnitude of the braking energy.

[0124] When the power equipment is in a braking state, the braking energy generated by the drive unit 21 is specifically electrical energy. The magnitude of the braking energy generated by the drive unit 21 can be regarded as the electrical energy generated by the drive motor of the drive unit 21 when it is in a power generation state. The magnitude of the electrical energy generated by the drive motor when it is in a power generation state can be used to measure the magnitude of the braking energy. For example, the magnitude of the braking energy can be measured by the magnitude of the voltage or current measured by the drive motor when it is in a power generation state.

[0125] The electric heating circuit 4 is controlled according to the temperature of the battery 11, including whether the electric heating circuit 4 is working or not. For example, when the temperature of the battery 11 is too low, the electric heating circuit 4 can be controlled to heat the battery 11 using braking energy, while the battery 11 is further heated through the electric heating circuit 4 to ensure that the battery 11 is heated to a suitable temperature range.

[0126] The electric heating circuit 4 is controlled according to the magnitude of the braking energy, including whether the electric heating circuit 4 is working or not. For example, if the braking energy is too small, it is insufficient to adjust the temperature of the battery 11 to a suitable temperature range. Therefore, while the braking energy supplies power to the braking resistor 220, the electric heating circuit 4 can be controlled to work. The battery 11 also supplies power to the braking resistor 220. The braking resistor 220 generates heat and transfers the heat to the battery 11 through the thermal management unit 5 to heat the battery 11. This achieves the simultaneous heating of the battery 11 using the braking energy and further heating of the battery 11 through the electric heating circuit 4, ensuring that the battery 11 is heated to a suitable temperature range.

[0127] In the above technical solution, by controlling the electric heating circuit 4 according to the temperature of the battery 11 or the magnitude of the braking energy, the battery 11 can be heated using the braking energy. At the same time, it is possible to choose whether to turn on the electric heating circuit 4 to further heat the battery 11, thereby further ensuring that the temperature of the battery 11 is adjusted to a suitable operating temperature range, so as to further ensure the working performance of the battery 11.

[0128] In some embodiments, controlling the electric heating circuit 4 according to the temperature of the battery 11 or the magnitude of the braking energy includes: the electric heating circuit 4 operating when the temperature of the battery 11 is less than a second preset temperature or the braking energy is less than a first preset energy value, wherein the second preset temperature is less than the first preset temperature.

[0129] The first preset energy value can be a preset value of braking energy that can satisfy the braking resistor 220 to do work and adjust the temperature of the battery 11 to a suitable operating temperature range. The first preset energy value can be used as a critical value to determine whether the electric heating circuit 4 needs to work.

[0130] For example, when the power equipment is in a braking state, the braking energy circuit 24 works, and the braking energy can supply power to the braking resistor 220. When the braking energy is less than the first preset energy value, the braking energy is insufficient to satisfy the work of the braking resistor 220. The heat generated by the braking resistor 220 is insufficient to heat the battery 11 to a suitable operating temperature range. The electric heating circuit 4 can be controlled to work, and the battery 11 also supplies power to the braking resistor 220. The braking resistor 220 generates heat and transfers the heat to the battery 11 through the thermal management unit 5 to heat the battery 11 until the battery 11 is heated to a suitable operating temperature range.

[0131] The second preset temperature can indicate that the temperature of battery 11 is too low. When the temperature of battery 11 is lower than the second preset temperature, the heat energy converted from braking energy alone is insufficient to adjust battery 11 to a suitable operating temperature range.

[0132] For example, when the power equipment is in braking mode, the braking energy circuit 24 operates, and the braking energy can supply power to the braking resistor 220. When the temperature of the battery 11 is lower than the second preset temperature, which is lower than the first preset temperature, a large amount of heat is required to heat the battery 11 to a suitable operating temperature range. When the braking energy is insufficient to heat the battery 11 to a suitable operating temperature range, the electric heating circuit 4 can be controlled to operate, and the battery 11 also supplies power to the braking resistor 220. The braking resistor 220 generates heat and transfers the heat to the battery 11 through the thermal management unit 5 to heat the battery 11 until the battery 11 is heated to a suitable operating temperature range.

[0133] In the above technical solution, when the temperature of the battery 11 is lower than the second preset temperature or the braking energy is lower than the first preset energy value, the electric heating circuit 4 is activated. This not only enables full utilization of the braking energy to heat the battery 11, but also allows the electric heating circuit 4 to further adjust the temperature of the battery 11 to a suitable operating temperature range when the temperature of the battery 11 is low or the braking energy is low and the braking energy alone cannot meet the heating requirements of the battery 11, thereby further ensuring the working performance of the battery 11.

[0134] In some embodiments, when the power equipment is not in a braking state, the electric heating circuit 4 is controlled according to the temperature of the battery 11; wherein, when the temperature of the battery 11 is less than a first preset temperature, the electric heating circuit 4 is activated and the thermal management unit 5 is activated, and the battery 11 supplies power to the braking resistor 220 to heat the battery 11; when the temperature of the battery 11 is greater than or equal to the first preset temperature, the electric heating circuit 4 is not activated and the thermal management unit 5 is not activated.

[0135] For example, the power source can be a vehicle, and the vehicle is not in a braking state, which can include the following situations: for example, the vehicle is in normal driving and the vehicle is not braking; or for example, the vehicle is not started.

[0136] When the power equipment is not in a braking state, the drive unit 21 does not generate braking energy. Since the battery 11 is electrically connected to the braking resistor 220 to form an electric heating circuit 4, when the temperature of the battery 11 is lower than a first preset temperature, the electric heating circuit 4 and the thermal management unit 5 operate. For example, the operation of the electric heating circuit 4 can be controlled by a button or program. When the electric heating circuit 4 is operating, the battery 11 supplies power to the braking resistor 220, which generates heat and transfers the heat to the battery thermal management module 15 through the resistance heat exchange module 223. The battery thermal management module 15 exchanges heat with the battery 11, thereby regulating the temperature of the battery 11 to heat it.

[0137] For example, when the temperature of battery 11 is greater than or equal to the first preset temperature, battery 11 does not need to be heated, electric heating circuit 4 does not work, battery 11 does not supply power to braking resistor 220; moreover, thermal management unit 5 does not work, circulating pump 13 does not work, and heat exchange medium does not circulate.

[0138] In the above technical solution, when the power equipment is not in a braking state, the heating circuit 4 can be controlled according to the temperature of the battery 11 to meet the heating requirements of the battery 11 when the power equipment is not in a braking state, thereby ensuring that the battery 11 can be in the normal operating temperature range and ensuring the working performance of the battery 11.

[0139] In some embodiments, refer to Figure 3 The battery 11 includes multiple battery branches 110 connected in parallel. When the electric heating circuit 4 is working, the battery branch 110 with the largest amount of power will give priority to supplying power to the braking resistor 220.

[0140] The amount of power and the relationship between the amounts of each battery branch 110 can be obtained in the following ways: for example, the battery 11 may also include a battery management system, which can measure the amount of power of each battery branch 110 and compare the relationship between the amounts of power of each battery branch 110.

[0141] For example, when the charge levels of the various battery branches 110 are inconsistent, the battery branch 110 with the lower charge can be disconnected, while the battery branch 110 with the highest charge remains connected. When the electric heating circuit 4 is working, the battery branch 110 with the highest charge supplies power to the braking resistor 220. The braking resistor 220 generates heat, which is then transferred to the battery 11 through the thermal management unit 5, thereby regulating the temperature of the battery 11.

[0142] For example, when the battery branch 110 with the largest charge supplies power to the braking resistor 220, the other battery branches 110 are in an open state. The braking resistor 220 can consume the charge of the battery branch 110 with the largest charge, and the battery branch 110 with the largest charge discharges through the braking resistor 220.

[0143] In the above technical solution, the battery branch 110 with the largest power supply prioritizes power supply to the braking resistor 220. This not only regulates the temperature of the battery 11, but also allows the battery branch 110 with the largest power supply to discharge through the braking resistor 220, which helps to achieve balance among multiple battery branches 110, improves the consistency of each battery branch 110, and ensures the service life of the battery 11.

[0144] In some embodiments, refer to Figure 3 The battery 11 includes multiple battery branches 110 connected in parallel. Each battery branch 110 is connected in series with a control switch 61. According to the relationship between the power of all battery branches 110, the control switch 61 is controlled so that the battery branch 110 with the largest power is preferentially connected to the braking resistor 220 to form an electric heating circuit 4.

[0145] Optionally, the battery system also includes a high-voltage box 6, and a control switch 61 may be located inside the high-voltage box 6. The control switch 61 may be a relay.

[0146] For example, when the charge of one battery branch 110 is the highest relative to the other battery branches 110, the control switch 61 of the battery branch 110 with the lowest charge can be disconnected. The control switch 61 of the battery branch 110 with the highest charge is in the connected state, and the battery branch 110 with the highest charge is connected, forming an electric heating circuit 4 with the braking resistor 220. Since the battery 11 is electrically connected to the braking resistor 220 to form the electric heating circuit 4, the electric heating circuit 4 is working. The battery branch 110 with the highest charge supplies power to the braking resistor 220, allowing it to discharge. After discharging, the control switches 61 of the other battery branches 110 are connected again to connect the other battery branches 110 to the braking resistor 220 to form the electric heating circuit 4, until the charge of each branch reaches balance.

[0147] The battery branch 110 with a larger capacity and the braking resistor 220 form an electric heating circuit 4. The battery branch 110 with a larger capacity can supply power to the braking resistor 220, which generates heat. The heat generated by the braking resistor 220 can heat the battery 11. If the battery 11 does not need to be heated, the heat generated by the braking resistor 220 can be released, for example, by cooling the braking resistor 220 with a cooling fan 23, so that the heat generated by the braking resistor 220 can be dissipated quickly.

[0148] When the charge levels of multiple battery branches 110 differ, the higher-charge battery branch 110 may discharge to the lower-charge battery branch 110, potentially damaging the battery 11. In the above technical solution, by controlling the control switch 61 according to the charge level relationship of all battery branches 110, the higher-charge battery branch 110 can form an electric heating circuit 4 with the braking resistor 220 to discharge the higher-charge battery branch 110. This helps to balance the charge levels of each battery branch 110, improves the consistency of the battery 11, reduces the maintenance cost of the battery 11, and ensures the lifespan of the battery 11.

[0149] In some embodiments, refer to Figure 3 The battery branch 110 includes at least one battery cell 111. Each battery branch 110 is connected in series with two control switches 61, and all battery cells 111 of each battery branch 110 are connected in series between the two control switches 61.

[0150] Battery branch 110 includes at least one battery cell 111, including the following situations: for example, each battery branch 110 has one battery cell 111 connected in series; or for example, each battery branch 110 has multiple battery cells 111 connected in series. One of the battery cells 111 may include one or more individual battery cells, and multiple individual battery cells may be connected in series, parallel, or mixed to directly form battery cell 111. Mixed connection means that multiple individual battery cells are connected in both series and parallel.

[0151] When each battery branch 110 is connected in series with a control switch 61, a failure of a single control switch 61 can easily cause each battery branch 110 to remain in a continuously connected state, making it difficult to adjust the power level of each battery branch 110 using the control switches 61. Therefore, by connecting two control switches 61 in series with each battery branch 110, and connecting all battery cells 111 of each battery branch 110 in series between the two control switches 61, if one control switch 61 of a battery branch 110 fails, the other control switch 61 can still work normally, improving the reliability of the control of the battery branch 110 and thus enabling balanced adjustment of the power level of each battery branch 110.

[0152] In some embodiments, refer to Figure 1 The battery 11 is adapted to be electrically connected to the drive unit 21 to form a battery charging and discharging circuit 3.

[0153] Battery 11 is electrically connected to drive unit 21 to form battery charging and discharging circuit 3. Battery 11 can supply power to drive unit 21 through battery charging and discharging circuit 3, enabling drive unit 21 to drive the power equipment to operate normally. For example, when the power equipment brakes, the drive motor changes from motor mode to generator mode and generates braking energy. Braking energy may include the electrical energy generated after the drive motor changes from motor mode to generator mode. The braking energy generated by drive unit 21 can charge battery 11 through battery charging and discharging circuit 3.

[0154] When the battery charging and discharging circuit 3 is working, it can be understood that the braking energy generated by the drive unit 21 charges the battery 11; when the battery charging and discharging circuit 3 is not working, it can be understood that the braking energy generated by the drive unit 21 does not charge the battery 11.

[0155] In the above technical solution, the battery 11 is electrically connected to the drive unit 21 to form a battery charging and discharging circuit 3. The battery 11 can supply power to the drive unit 21 through the battery charging and discharging circuit 3. The braking energy generated when the drive unit 21 of the power equipment brakes can charge the battery 11 through the battery charging and discharging circuit 3, so as to make full use of the braking energy.

[0156] In some embodiments, when the power device is in a braking state, the braking energy circuit 24 operates preferentially, and the driving unit 21 uses the braking energy generated to heat the battery 11 preferentially.

[0157] Since the temperature of battery 11 affects its working performance (including the charging and discharging efficiency of battery 11), the braking energy circuit 24 operates first to heat battery 11, so that battery 11 is within the normal operating temperature range. This ensures that the battery charging and discharging circuit 3 works normally, allowing battery 11 to supply power to drive unit 21 normally, thus ensuring the normal use of the power equipment.

[0158] The braking energy circuit 24 operates preferentially relative to the battery charging and discharging circuit 3. When the power equipment is in a braking state and generates braking energy, the braking energy can be used to power the braking resistor 220 through the braking energy circuit 24. The braking energy can also be used to charge the battery 11 through the battery charging and discharging circuit 3. Rather than the braking energy charging the battery 11 through the battery charging and discharging circuit 3, the braking energy can preferentially be used to power the braking resistor 220 through the braking energy circuit 24.

[0159] When the power equipment is in a braking state, the braking energy circuit 24 operates preferentially, and the driving unit 21 uses the braking energy generated to heat the battery 11 preferentially, which may include the following situations:

[0160] For example, when the power equipment is in a braking state, the drive motor of the drive unit 21 operates in a generating state, converting part of the kinetic energy of the power equipment into electrical energy. The electrical energy can be used for the aforementioned braking energy. Normally, the current will automatically flow to the circuit with a lower voltage. The braking energy circuit 24 has a lower voltage than the battery charging and discharging circuit 3. Therefore, the braking energy generated by the drive unit 21 will preferentially supply power to the braking resistor 220 of the braking resistor 22 through the braking energy circuit 24. The braking resistor 220 heats up and conducts the heat to the resistance heat exchange module 223. The resistance heat exchange module 223 transfers the heat to the battery thermal management module 15, thereby heating the battery 11.

[0161] For example, when the braking energy generated by the drive unit 21 is small, the braking energy circuit 24 is working, the thermal management unit 5 is working, and the battery charging and discharging circuit 3 is not working, and the braking energy is used to heat the battery 11; when the braking energy generated by the drive unit 21 is large, the braking energy circuit 24 is working, the thermal management unit 5 is working, and the battery charging and discharging circuit 3 is working, and the braking energy can be used to heat the battery 11, and at the same time the braking energy can also be used to charge the battery 11.

[0162] For example, when the power equipment is in a braking state, the drive unit 21 generates braking energy, which can control the braking energy circuit 24 to work first, and the thermal management unit 5 to work. The braking energy can be used to heat the battery 11. When the temperature of the battery 11 is adjusted to a suitable operating temperature range, the battery charging and discharging circuit 3 can be controlled to work, and the remaining braking energy can be used to charge the battery 11.

[0163] In the above technical solution, when the power equipment is in a braking state, the braking energy circuit 24 operates first, and the driving unit 21 uses the generated braking energy to heat the battery 11 first, which can regulate the temperature of the battery 11 and ensure the working performance of the battery 11. On the other hand, the braking resistor 22 absorbs a portion of the braking energy, which can improve the braking energy recovery efficiency and avoid the problem of the battery 11 being damaged because the braking energy is still charging the battery 11 when the remaining charge of the battery 11 is too high.

[0164] In some embodiments, when the power device is in a braking state, the battery charging and discharging circuit 3 is controlled according to the remaining charge of the battery 11 or the amount of braking energy generated by the drive unit 21.

[0165] The battery charging and discharging circuit 3 is controlled according to the remaining power of the battery 11, including controlling whether the battery charging and discharging circuit 3 is working or not, according to the remaining power of the battery 11.

[0166] For example, when the power equipment is in a braking state, the drive unit 21 generates braking energy. When the battery 11 has a large remaining charge (e.g., the battery 11 is fully charged), the battery charging and discharging circuit 3 can be controlled not to work, so the braking energy does not charge the battery 11. For example, the battery 11 has an overcharge protection device. When the battery 11 has a large remaining charge and does not need to be charged, the overcharge protection device works, making it difficult for the battery 11 to be charged.

[0167] For example, when the power equipment is in a braking state, the drive unit 21 generates braking energy. When the remaining power of the battery 11 is low, the battery 11 needs to be charged. The battery charging and discharging circuit 3 can be controlled to work, and the drive unit 21 will charge the battery 11 through the battery charging and discharging circuit 3 with the generated braking energy.

[0168] The battery charging and discharging circuit 3 is controlled according to the magnitude of the braking energy generated by the drive unit 21, including controlling whether the battery charging and discharging circuit 3 is working or not, according to the magnitude of the braking energy generated by the drive unit 21.

[0169] For example, when the power equipment is in a braking state, the drive unit 21 generates braking energy. When the temperature of the battery 11 is low, and the temperature of the battery 11 is less than the first preset temperature, the braking energy generated by the drive unit 21 is less. The battery charging and discharging circuit 3 can be controlled not to work, and the braking energy will not charge the battery 11. The braking energy can be used to heat the battery 11. In this way, when the braking energy is less, the battery 11 can be heated first, rather than charged.

[0170] For example, when the power equipment is in braking mode, the drive unit 21 generates braking energy. When the temperature of the battery 11 is low, below the first preset temperature, the drive unit 21 generates a large amount of braking energy, which is sufficient to adjust the temperature of the battery 11 to a suitable operating temperature range. This allows the battery charging and discharging circuit 3 to operate, charging the battery 11. Simultaneously, the thermal management unit 5 can be controlled to operate, and the braking energy can be used to heat the battery 11. Alternatively, the thermal management unit 5 can be controlled first, using the braking energy to heat the battery 11, and then the battery charging and discharging circuit 3 can be controlled to operate, with the remaining braking energy charging the battery 11.

[0171] In the above technical solution, when the power equipment is in a braking state, the battery charging and discharging circuit 3 is controlled according to the remaining charge of the battery 11. When the battery charging and discharging circuit 3 is working, the braking energy can charge the battery 11, fully recovering and utilizing the braking energy, which helps to increase the charge of the battery 11. When the remaining charge of the battery 11 is too high, the problem of damage to the battery 11 caused by the braking energy still charging the battery 11 can be avoided. By controlling the battery charging and discharging circuit 3 according to the amount of braking energy generated by the drive unit 21, the energy utilization method can be selectively determined as needed.

[0172] In some embodiments, controlling the battery charging and discharging circuit 3 according to the remaining power of the battery 11 includes: when the remaining power of the battery 11 is less than a preset power, the battery charging and discharging circuit 3 operates, and the driving unit 21 uses the generated braking energy to charge the battery 11.

[0173] The remaining power of battery 11 can be obtained in the following ways: for example, battery 11 may also include a battery management system, which can measure the remaining power of battery 11.

[0174] When the power equipment is in braking mode, the battery charging and discharging circuit 3 can be controlled to work, and the braking energy generated by the drive unit 21 charges the battery 11 through the battery charging and discharging circuit 3. For example, the preset charge can be a preset value for determining whether the battery 11 can be charged. When the remaining charge of the battery 11 is less than the preset charge, it is determined that the battery 11 can be charged, and the battery charging and discharging circuit 3 works, and the drive unit 21 uses the generated braking energy to charge the battery 11; when the remaining charge of the battery 11 is greater than or equal to the preset charge, it is determined that the battery 11 does not need to be charged, and the battery charging and discharging circuit 3 does not work, and the drive unit 21 uses the generated braking energy to supply power to the braking resistor 220. The braking energy can be released through the heating of the braking resistor 220.

[0175] In the above technical solution, the braking energy generated by the drive unit 21 is used to charge the battery 11 to increase the battery capacity. When the power device is a vehicle, the driving range of the vehicle can be increased.

[0176] In some embodiments, refer to Figure 3 The battery 11 includes multiple battery branches 110 connected in parallel, and the drive unit 21 uses the braking energy generated to charge the battery branch 110 with the lowest charge first.

[0177] The drive unit 21 will preferentially charge the battery branch 110 with the smallest battery charge using the generated braking energy, relative to the battery branch 110 with the largest battery charge, as detailed below:

[0178] For example, when the charge levels of multiple battery branches 110 are inconsistent, battery 11 can automatically disconnect the battery branch 110 with the higher charge level, while the battery branch 110 with the lowest charge level remains connected. This lowest charge battery branch 110 can connect to drive unit 21 to form a battery charging / discharging circuit 3. Drive unit 21 can prioritize charging the battery branch 110 with the lowest charge level using the generated braking energy. After the lowest charge battery branch 110 is fully charged, its charge level increases, the circuit disconnects, and another battery branch 110 with the lowest charge level connects. Drive unit 21 then charges this battery branch 110 with the generated braking energy until the charge levels of all battery branches 110 are balanced.

[0179] Optionally, when the battery 11 includes multiple battery branches 110 connected in parallel, the battery thermal management module 15 may also include multiple thermal management branches connected in parallel. The number of thermal management branches may be the same as the number of battery branches 110 and correspond one-to-one. Each thermal management branch may perform temperature regulation (e.g., heating) on ​​the corresponding battery branch 110.

[0180] In the above technical solution, the driving unit 21 uses the generated braking energy to charge the battery branch 110 with the lowest charge first, which helps to achieve balance among multiple battery branches 110, improve the consistency of each battery branch 110, and ensure the service life of the battery 11.

[0181] In some embodiments, refer to Figure 2 The energy management system of the power equipment also includes a cooling fan 23, which is used to dissipate heat from the braking resistor 220; and controls the battery charging and discharging circuit 3 according to the remaining power of the battery 11, including: when the remaining power of the battery 11 is greater than or equal to the preset power, the battery charging and discharging circuit 3 does not work and the cooling fan 23 works.

[0182] For example, when the vehicle is braking, the braking energy generated by the drive unit 21 can power the braking resistor 220. When the temperature of the battery 11 is greater than or equal to the first preset temperature, the battery 11 does not need to be heated, the thermal management unit 5 does not work, and the heat exchange medium in the resistor heat exchange module 223 and the battery thermal management module 15 does not circulate. Furthermore, when the remaining charge of the battery 11 is greater than or equal to the preset charge, the battery 11 does not need to be charged, and the battery charging and discharging circuit 3 does not work. At this time, the heat generated by the braking resistor 220 can be quickly dissipated by the cooling fan 23, and the braking resistor 220 can consume braking energy in the form of heat.

[0183] In the above technical solution, the cooling fan 23 works and dissipates heat from the braking resistor 220, which can help the braking resistor 220 consume braking energy, resulting in better heat dissipation. It can also prevent the temperature of the braking resistor 220 from getting too high, which would cause the ambient temperature to get too high and affect the service life of other surrounding components.

[0184] In some embodiments, the battery charging and discharging circuit 3 is controlled according to the magnitude of the braking energy generated by the drive unit 21, including: when the braking energy is less than a second preset energy value, the braking energy circuit 24 is activated and the battery charging and discharging circuit 3 is deactivated; when the braking energy is greater than or equal to the second preset energy value, both the braking energy circuit 24 and the battery charging and discharging circuit 3 are activated.

[0185] For example, when the power equipment is in a braking state, the drive unit 21 generates braking energy. When the braking energy is less than the second preset energy value, the braking energy does not meet the work of the braking resistor 220. The braking energy (including current) can automatically flow to the braking energy circuit 24, and the battery charging and discharging circuit 3 does not have braking energy passing through it. That is, the braking energy circuit 24 works and the battery charging and discharging circuit 3 does not work.

[0186] For example, when the braking energy is greater than or equal to the second preset energy value, the braking energy satisfies the work done by the braking resistor 220. The braking energy (including current) can automatically flow to the braking energy circuit 24 and at the same time flow to the battery charging and discharging circuit 3. Both the braking energy circuit 24 and the battery charging and discharging circuit 3 are working. The braking energy can be converted into heat energy to heat the battery 11 and can also charge the battery 11.

[0187] In the above technical solution, when the braking energy is less than the second preset energy value, the braking energy circuit 24 operates while the battery charging and discharging circuit 3 does not operate. When the braking energy is greater than or equal to the second preset energy value, both the braking energy circuit 24 and the battery charging and discharging circuit 3 operate. The braking energy can be converted into heat energy to heat the battery 11 to ensure the working performance of the battery 11, and it can also charge the battery 11 to increase the battery's capacity, thus achieving full recovery and utilization of braking energy. Furthermore, when the braking energy is small, it is preferentially used to heat the battery 11, while when the braking energy is large, it can both heat and charge the battery 11. This achieves the goal of prioritizing the use of braking energy for heating the battery 11 to ensure its working performance, while also fully utilizing the braking energy.

[0188] In some embodiments, refer to Figure 2 The energy management system of the power equipment also includes a cooling fan 23, which is used to dissipate heat from the braking resistor 22.

[0189] For example, the need for a cooling fan 23 can be selected based on the type of power equipment and the braking force of the power equipment; when the power equipment is a vehicle, large vehicles (such as heavy trucks) usually have a large braking force and generate a large braking energy, and the braking resistor 220 installed in such vehicles needs to use a cooling fan 23 to assist in heat dissipation.

[0190] For example, small vehicles (such as cars) typically have lower braking force and generate less braking energy. The braking resistor 220 installed in such vehicles may not need to use a cooling fan 23 and can rely mainly on natural cooling.

[0191] For example, the cooling fan 23 can be located close to the braking resistor 220. When the temperature of the battery 11 is greater than or equal to the preset temperature, the battery 11 does not need to be heated, the thermal management unit 5 does not work, and the heat exchange medium in the resistor heat exchange module 223 and the battery thermal management module 15 does not circulate. Furthermore, when the remaining charge of the battery 11 is greater than or equal to the preset charge, the battery 11 does not need to be charged. The braking energy generated by the drive unit 21 can be used to power the braking resistor 220. The braking resistor 220 generates heat. When the cooling fan 23 works, it can promote the airflow around it, thereby dissipating heat from the braking resistor 220.

[0192] In the above technical solution, the cooling fan 23 is used to dissipate heat from the braking resistor 22, which can help the braking resistor 22 consume the braking energy generated by the drive unit 21, resulting in better heat dissipation and preventing the braking resistor 22 from overheating and affecting the operation of other surrounding components.

[0193] In some embodiments, the resistance value of the braking resistor 220 is adjustable.

[0194] For example, when the temperature of battery 11 is low and the battery 11 requires a lot of heat, the resistance value of braking resistor 220 can be increased to increase the heat generation of braking resistor 220. When the drive unit 21 supplies power to braking resistor 220 with the generated braking energy, or when battery 11 supplies power to braking resistor 220, the heat generation of braking resistor 220 is greater due to its larger resistance value. The heat generated by braking resistor 220 is transferred to battery 11 through thermal management unit 5 to adjust the temperature of battery 11 and control the temperature of battery 11 within the normal temperature range.

[0195] For example, when the battery 11 requires less heat, the resistance value of the braking resistor 220 can be reduced. When the drive unit 21 supplies power to the braking resistor 220 with the generated braking energy, or when the battery 11 supplies power to the braking resistor 220, the braking resistor 220 generates less heat due to its lower resistance value. The heat generated by the braking resistor 220 is transferred to the battery 11 through the thermal management unit 5 to adjust the temperature of the battery 11 and keep the temperature of the battery 11 within the normal temperature range.

[0196] For example, when the braking force of the power equipment is too large, the braking energy generated by the drive unit 21 is large. In this case, the braking energy can be consumed by increasing the resistance value of the braking resistor 220.

[0197] The adjustable resistance value of the braking resistor 220 can meet the heating requirements of the battery 11 and ensure the recovery rate of braking energy.

[0198] Secondly, embodiments of the present invention also provide a power device, including: the energy management system described above.

[0199] For example, the power source can be a vehicle, which can be a pure electric vehicle or a hydrogen fuel cell vehicle.

[0200] For example, when the vehicle is a pure electric vehicle, using the aforementioned energy management system 100, the braking energy generated by the drive unit 21 can charge the battery 11 through the battery charging and discharging circuit 3; the braking energy generated by the drive unit 21 can also supply power to the braking resistor 220 through the braking energy circuit 24. The braking resistor 220 generates heat and transfers the energy to the battery 11 through the thermal management unit 5, thereby regulating the temperature of the battery 11. The battery 11 and the braking resistor 220 are electrically connected to form an electric heating circuit 4. When the vehicle is not braking, the electric heating circuit 4 is activated, and the battery 11 can charge the braking resistor 220. The braking resistor 220 generates heat and transfers the energy to the battery 11 through the thermal management unit 5, thereby regulating the temperature of the battery 11.

[0201] For example, when the vehicle is a hydrogen fuel cell vehicle, the operation of the energy management system 100 during vehicle braking is the same as that of the pure electric vehicle described above. Furthermore, because hydrogen fuel cell vehicles adjust power more slowly under low-temperature conditions, a greater amount of energy is generated during the power adjustment process. If the vehicle needs to stop after starting, the energy generated during the power adjustment process needs to be released. This energy can be consumed using the braking resistor 22 in the energy management system 100. If the temperature of the battery 11 is lower than the first preset temperature at this time, the braking energy circuit 24 and the thermal management unit 5 can be controlled to operate, and the energy generated during the power adjustment process is used to heat the battery 11.

[0202] Therefore, by adopting the energy management system 100 of the power equipment described above, both braking energy recovery and temperature regulation of the battery 11 can be achieved, making full use of braking energy. Furthermore, when the power equipment is in a non-braking state, there is no need to set up an additional heating system to heat the battery 11. The battery 11 can supply power to the braking resistor 220 of the braking resistor 22. The braking resistor 220 generates heat and transfers the heat through the thermal management unit 5 to heat the battery 11, thereby ensuring the working performance of the battery 11. Moreover, the overall structure is simple and can save costs.

[0203] Thirdly, referring to Figures 1-4 The present invention also provides a control method for an energy management system 100 of a power device. The energy management system 100 includes a braking resistor 220 and a thermal management unit 5. The braking resistor 220 is adapted to be electrically connected to the drive unit 21 of the power device to form a braking energy circuit 24. The braking resistor 220 is adapted to be electrically connected to the battery 11 of the power device to form an electric heating circuit 4. The thermal management unit 5 is used to heat the battery 11 with the heat generated by the braking resistor 220.

[0204] The control method includes: determining whether the power equipment is in a braking state; if the power equipment is in a braking state, determining whether the temperature of the battery 11 is lower than the first preset temperature; if the temperature of the battery 11 is lower than the first preset temperature, the braking energy circuit 24 is activated and the thermal management unit 5 is activated.

[0205] When the power equipment brakes, the drive unit 21 changes from motor mode to generator mode. The drive unit can convert some of the kinetic energy into electrical energy, generating a force opposite to that when the power equipment is driven, thus braking the power equipment.

[0206] For example, the power unit can be a vehicle, and the drive unit 21 can include a drive motor and motor control components. The drive motor can drive the vehicle's wheels to rotate, thereby driving the vehicle. When the vehicle brakes, the battery 11 stops supplying power to the drive unit 21, but the vehicle's wheels continue to rotate. The drive motor of the drive unit 21 can rotate under the drive of the wheels. At this time, the drive motor operates in a generator state, converting part of the vehicle's kinetic energy into electrical energy. Simultaneously, it applies a feedback torque to the drive shaft, generating a force opposite to the vehicle's driving motion, thus braking the vehicle. Therefore, when the vehicle brakes, the drive motor switches from electric motor mode to generator mode and generates braking energy. The braking energy can include the electrical energy generated by the drive motor after switching from electric motor mode to generator mode.

[0207] The drive unit 21 is electrically connected to the braking resistor 220 to form a braking energy circuit 24. The braking energy generated by the drive unit 21 can supply power to the braking resistor 220 through the braking energy circuit 24. The braking resistor 220 generates heat when energized. The thermal management unit 5 can transfer the energy to the battery to regulate the temperature of the battery 11, thereby using the braking energy to heat the battery 11.

[0208] Battery 11 is electrically connected to braking resistor 220 to form electric heating circuit 4. Battery 11 can supply power to braking resistor 220, which generates heat. Thermal management unit 5 can transfer energy to battery to regulate the temperature of battery 11. Thus, the electrical energy of battery 11 can be converted into heat energy through braking resistor 220 to heat battery 11. For example, when braking energy cannot meet the heating requirements of battery 11 or when the power equipment is not in a braking state, electric heating circuit 4 can be used to heat battery 11.

[0209] The way in which the battery 11 is electrically connected to the braking resistor 220 to form the electric heating circuit 4 can include the following example: the braking resistor 220 has a first interface 221 and a second interface 222, the first interface 221 of the braking resistor 220 is electrically connected to the positive terminal of the battery 11, and the second interface 222 of the braking resistor 220 is electrically connected to the negative terminal of the battery 11, so that the battery 11 is electrically connected to the braking resistor 220 and the battery 11 can supply power to the braking resistor 220.

[0210] For example, when the battery 11 is at a low temperature and the vehicle is braking, the braking energy circuit 24 is activated, and the braking energy generated by the drive unit 21 supplies power to the braking resistor 220 through the braking energy circuit 24; when the battery 11 is at a low temperature and the vehicle is not braking, the battery 11 can supply power to the braking resistor 220 through a button or program control.

[0211] When the braking energy circuit 24 is working, it can be understood that the braking energy supplies power to the braking resistor 220, causing the braking resistor 220 to heat up. When the electric heating circuit 4 is working, it can be understood that the battery 11 supplies power to the braking resistor 220, causing the braking resistor 220 to heat up. When the electric heating circuit 4 is not working, it can be understood that the battery 11 does not supply power to the braking resistor 220.

[0212] When the power equipment is in braking mode, the braking energy generated by the drive unit 21 can supply power to the braking resistor 220, causing the braking resistor 220 to heat up. This heat is then transferred to the battery 11 via the thermal management unit 5 to heat the battery. When the braking energy is insufficient to meet the heating requirements of the battery 11, the battery 11 can supply power to the braking resistor 220, and the heat generated by the braking resistor 220 can be transferred to the battery 11 via the thermal management unit 5 to heat the battery 11. When the power equipment is not in braking mode, the battery 11 can supply power to the braking resistor 220, and the heat generated by the braking resistor 220 can be transferred to the battery 11 via the thermal management unit 5 to heat the battery 11.

[0213] For example, the thermal management unit 5 may include a battery thermal management module 15 and a resistance heat exchange module 223. The battery thermal management module 15 and the resistance heat exchange module 223 are connected to form a thermal management loop 7 for the flow of the heat exchange medium. The battery thermal management module 15 is used to regulate the temperature of the battery 11. The resistance heat exchange module 223 is thermally connected to or in thermal contact with the braking resistor 220. When the resistance heat exchange module 223 is connected to the braking resistor 220, the resistance heat exchange module 223 can be welded to the braking resistor 220, or the resistance heat exchange module 223 can be connected to the braking resistor 220 through thermally conductive adhesive. Through thermal connection or thermal contact with the braking resistor 220, the resistance heat exchange module 223 can achieve heat exchange with the braking resistor 220, and the braking resistor 220 can conduct heat to the resistance heat exchange module 223.

[0214] For example, the resistance heat exchange module 223 is connected to the battery thermal management module 15 to form a thermal management circuit 7. The thermal management circuit 7 allows for the flow of a heat exchange medium. When the thermal management circuit 7 is working, after the resistance heat exchange module 223 exchanges heat with the braking resistor 220, the resistance heat exchange module 223 can transfer heat to the battery thermal management module 15 through the thermal management circuit 7, allowing the battery thermal management module 15 to heat the battery 11. When the thermal management circuit 7 is not working, the heat from the braking resistor 220 will not be transferred to the battery thermal management module 15, and the battery 11 will not be heated.

[0215] For example, the resistance heat exchange module 223 may include a heat exchange tube, within which a heat exchange medium flows. The heat exchange medium may include water. The heat exchange medium within the resistance heat exchange module 223 can exchange heat with the braking resistor 220. The battery thermal management module 15 may have a heat exchange channel, within which a heat exchange medium flows. The heat exchange medium can exchange heat with the battery 11 to regulate the temperature of the battery 11. The outlet 225 of the resistance heat exchange module 223 is connected to the inlet of the heat exchange channel, and the inlet 224 of the resistance heat exchange module 223 is connected to the outlet of the heat exchange channel. The heat exchange medium can circulate between the resistance heat exchange module 223 and the battery thermal management module 15. A circulation pump 13 can be connected in series on the thermal management circuit 7. The circulation pump 13 can drive the heat exchange medium in the resistance heat exchange module 223 to flow into the battery thermal management module 15 through the outlet 225. The heat exchange medium can exchange heat with the battery 11, thereby regulating the temperature of the battery 11. After exchanging heat with the battery 11, the heat exchange medium flows back to the resistance heat exchange module 223 from the inlet 224 and continues to exchange heat with the braking resistor 220, continuing to circulate.

[0216] For example, when the battery 11 is at a low temperature and the power equipment is braking, the braking energy circuit 24 operates, and the braking energy generated by the drive unit 21 supplies power to the braking resistor 220 through the braking energy circuit 24. When the battery 11 is at a low temperature and the power equipment is not braking, the battery 11 can supply power to the braking resistor 220 via a button or program control. In both of these cases, the braking resistor 220 is energized and heats up, exchanging heat with the heat exchange medium. Driven by the circulating pump 13, the heat exchange medium circulates from the resistance heat exchange module 223 to the battery thermal management module 15, allowing the battery thermal management module 15 to exchange heat with the battery 11, thereby heating the battery 11.

[0217] When the thermal management circuit 7 is working, it can be understood that the heat exchange medium within the thermal management circuit 7 is circulating, for example, the circulating pump 13 is working; when the thermal management circuit 7 is not working, it can be understood that the heat exchange medium within the thermal management circuit 7 is not flowing, for example, the circulating pump 13 stops working.

[0218] The control method of the vehicle's energy management system 100 may include:

[0219] Determine if the vehicle is in a braking state;

[0220] If the vehicle is in a braking state, determine whether the temperature of battery 11 is lower than the first preset temperature;

[0221] If the temperature of battery 11 is lower than the first preset temperature, the braking energy circuit 24 and the thermal management unit 5 are activated. The braking energy generated by the drive unit 21 supplies power to the braking resistor 220 through the braking energy circuit 24. The braking resistor 220 generates heat and transfers the heat to the battery 11 through the thermal management unit 5 to heat the battery 11.

[0222] The first preset temperature can be the lowest temperature that ensures the battery 11 can work normally.

[0223] In the above technical solution, when the power equipment is in a braking state, the braking energy generated by the drive unit 21 supplies power to the braking resistor 220 through the braking energy circuit 24. The braking resistor 220 heats up and transfers the heat through the thermal management unit 5, thereby heating the battery 11 and making full use of the braking energy. The battery 11 can directly supply power to the braking resistor 220 through the electric heating circuit 4. The braking resistor 220 generates heat when energized and transfers the heat through the thermal management unit 5. The thermal management unit 5 uses the heat generated by the braking resistor 220 to heat the battery, which can regulate the temperature of the battery 11 and ensure the working performance of the battery 11. This makes the overall structure simpler and reduces costs. In addition, since the power equipment is a vehicle, in the case of emergency braking, the feedback torque applied to the drive shaft is too large, which can easily cause excessive tire wear. By recovering some braking energy through the braking resistor 220, the braking purpose can be achieved, and tire wear can be reduced, ensuring the service life of the tires.

[0224] In some embodiments, if the temperature of the battery 11 is lower than the first preset temperature, the braking energy circuit 24 and the thermal management unit 5 operate, including: determining whether the temperature of the battery 11 is lower than the second preset temperature, and the second preset temperature is lower than the first preset temperature; if the temperature of the battery 11 is lower than the second preset temperature, controlling the electric heating circuit 4 to operate; if the temperature of the battery 11 is greater than or equal to the second preset temperature, controlling the electric heating circuit 4 not to operate.

[0225] For example, the first preset temperature can be the lowest temperature that ensures the battery 11 can work normally; the second preset temperature can indicate that the temperature of the battery 11 is too low. When the temperature of the battery 11 is lower than the second preset temperature, the heat energy converted from braking energy alone is insufficient to adjust the battery 11 to a suitable operating temperature range.

[0226] For example, a temperature sensor can be installed on the battery 11 to detect the temperature of the battery 11. When the temperature sensor detects that the temperature of the battery 11 is lower than the first preset temperature, the braking energy circuit 24 is activated, and the thermal management unit 5 is also activated. The braking energy generated by the drive unit 21 supplies power to the braking resistor 220. The braking resistor 220 heats up and conducts the heat to the resistance heat exchange module 223. The resistance heat exchange module 223 can transfer the heat to the battery thermal management module 15 through the thermal management unit 5. The battery thermal management module 15 can heat the battery 11.

[0227] For example, when the temperature sensor detects that the temperature of the battery 11 is greater than or equal to the first preset temperature, the thermal management unit 5 does not work, the heat exchange medium in the thermal management unit 5 does not circulate, the braking energy circuit 24 works, the braking energy generated by the drive unit 21 supplies power to the braking resistor 220, the braking resistor 220 generates heat, which can consume the braking energy; when the remaining power of the battery 11 is low, the braking energy can also be used to charge the battery 11.

[0228] For example, if the temperature of battery 11 is lower than the second preset temperature, more heat is required to heat battery 11 to the appropriate operating temperature range. When the braking energy is insufficient to heat battery 11 to the appropriate operating temperature range, the electric heating circuit 4 can be controlled to operate, and battery 11 also supplies power to braking resistor 220. Braking resistor 220 generates heat and transfers the heat to battery 11 through thermal management unit 5 to heat battery 11 until battery 11 is heated to the appropriate operating temperature range.

[0229] For example, if the temperature of battery 11 is greater than or equal to the second preset temperature, then less heat is required to heat battery 11 to the appropriate operating temperature range, and the braking energy is sufficient to heat battery 11 to the appropriate operating temperature range. Battery 11 does not need to supply power to braking resistor 220, and the electric heating circuit 4 can be controlled to not work.

[0230] In the above technical solution, when the temperature of the battery 11 is lower than the second preset temperature, the electric heating circuit 4 is controlled to work to heat the battery 11. When the temperature of the battery 11 is low or the braking energy is small and the braking energy alone cannot meet the heating requirements of the battery 11, the electric heating circuit 4 can further adjust the temperature of the battery 11 to a suitable operating temperature range to further ensure the working performance of the battery 11. When the temperature of the battery 11 is greater than or equal to the second preset temperature, the electric heating circuit 4 is controlled not to work, which can prevent the temperature of the battery 11 from being heated too high, thereby achieving full utilization of the braking energy and adjusting the temperature of the battery 11 to a suitable operating temperature range to ensure the working performance of the battery 11.

[0231] In some embodiments, if the temperature of the battery 11 is lower than the first preset temperature, the braking energy circuit 24 and the thermal management unit 5 operate, including: determining whether the braking energy is lower than the first preset energy value; if the braking energy is lower than the first preset energy value, controlling the electric heating circuit 4 to operate; if the braking energy is greater than or equal to the first preset energy value, controlling the electric heating circuit 4 not to operate.

[0232] The first preset energy value can be a preset value of braking energy that can satisfy the braking resistor 220 to do work and adjust the temperature of the battery 11 to a suitable operating temperature range. The first preset energy value can be used as a critical value to determine whether the electric heating circuit 4 needs to work.

[0233] For example, when the power equipment is in a braking state, the braking energy circuit 24 works, and the braking energy can supply power to the braking resistor 220. When the braking energy is less than the first preset energy value, the braking energy is insufficient to satisfy the work of the braking resistor 220. The heat generated by the braking resistor 220 is insufficient to heat the battery 11 to a suitable operating temperature range. The electric heating circuit 4 can be controlled to work, and the battery 11 also supplies power to the braking resistor 220. The braking resistor 220 generates heat and transfers the heat to the battery 11 through the thermal management unit 5 to heat the battery 11 until the battery 11 is heated to a suitable operating temperature range.

[0234] In the above technical solution, when the power equipment is in a braking state and the battery 11 temperature is low, braking energy can be used to heat the battery 11 to increase its temperature. Furthermore, by controlling whether the electric heating circuit 4 operates based on the magnitude of the braking energy, when the braking energy is too low to meet the heating requirements of the battery 11, the electric heating circuit 4 can operate to heat the battery 11, ensuring that the battery 11 temperature is adjusted to within the operating temperature range. When the braking energy is large enough to meet the heating requirements of the battery 11, the electric heating circuit 4 can be deactivated. This ensures the battery 11 temperature while saving energy. This achieves full utilization of braking energy to heat the battery 11, and when the braking energy is low and insufficient to meet the heating requirements of the battery 11, the electric heating circuit 4 can further adjust the battery temperature to a suitable operating temperature range, further ensuring the battery 11's performance.

[0235] In some embodiments, refer to Figure 1 The battery 11 is adapted to be electrically connected to the drive unit 21 to form a battery charging and discharging circuit 3. If the power equipment is in a braking state, it is determined whether the remaining power of the battery 11 is less than the preset power. If the remaining power of the battery 11 is less than the preset power, the battery charging and discharging circuit 3 is controlled to work, and the drive unit 21 uses the generated braking energy to charge the battery 11. If the remaining power of the battery 11 is greater than or equal to the preset power, the battery charging and discharging circuit 3 is controlled not to work.

[0236] Battery 11 is electrically connected to drive unit 21 to form battery charging and discharging circuit 3. Battery 11 can supply power to drive unit 21 through battery charging and discharging circuit 3, enabling drive unit 21 to drive the power equipment to operate normally. For example, when the power equipment brakes, the drive motor of drive unit 21 changes from motor mode to generator mode and generates braking energy. The braking energy may include the electrical energy generated after the drive motor changes from motor mode to generator mode. The braking energy generated by drive unit 21 can charge battery 11 through battery charging and discharging circuit 3.

[0237] When the battery charging and discharging circuit 3 is working, it can be understood that the braking energy generated by the drive unit 21 charges the battery 11; when the battery charging and discharging circuit 3 is not working, it can be understood that the braking energy generated by the drive unit 21 does not charge the battery 11.

[0238] For example, battery 11 may include a battery management system that can determine the remaining power of battery 11.

[0239] When the power equipment is in braking state and the remaining power of the battery 11 is less than the preset power, the battery charging and discharging circuit 3 can be controlled to work, and the braking energy generated by the drive unit 21 charges the battery 11 through the battery charging and discharging circuit 3.

[0240] For example, the preset charge level can be a preset value for determining whether battery 11 can be charged. When the remaining charge level of battery 11 is less than the preset charge level, it is determined that battery 11 can be charged, and the battery charging and discharging circuit 3 works, and the drive unit 21 uses the generated braking energy to charge battery 11. When the remaining charge level of battery 11 is greater than or equal to the preset charge level, it is determined that battery 11 does not need to be charged, and the battery charging and discharging circuit 3 does not work, the braking energy circuit 24 works, and the drive unit 21 uses the generated braking energy to power the braking resistor 220. The braking resistor 220 can dissipate the braking energy through heat dissipation.

[0241] In the above technical solution, the battery charging and discharging circuit 3 is controlled to work when the remaining power of the battery 11 is less than the preset power; the battery charging and discharging circuit 3 is controlled to not work when the remaining power of the battery 11 is greater than or equal to the preset power. The driving unit 21 uses the braking energy generated to charge the battery 11, which can recover and utilize the braking energy to increase the power of the battery 11. Furthermore, by controlling the battery charging and discharging circuit 3 based on the remaining power of the battery 11, it is determined whether to charge the battery 11, which can prevent the battery 11 from being damaged by overcharging.

[0242] In some embodiments, refer to Figure 3 The battery 11 includes multiple battery branches 110 connected in parallel. The battery charging and discharging circuit 3 controls the operation of the battery charging and discharging circuit, including: the drive unit 21 uses the generated braking energy to charge the battery branch 110 with the smallest charge.

[0243] For example, the battery branch 110 with the lowest capacity also has the lowest voltage.

[0244] The drive unit 21 prioritizes charging the battery branch 110 with the lowest charge using the generated braking energy. Specifically, for example, when the charges of multiple battery branches 110 are inconsistent (i.e., their voltages are inconsistent), the battery 11 can automatically disconnect the battery branch 110 with the higher voltage. The battery branch 110 with the lowest charge can then connect to the drive unit 21 to form a battery charging / discharging circuit 3. The drive unit 21 can then charge the battery branch 110 with the lowest voltage using the generated braking energy, thus prioritizing charging the battery branch 110 with the lowest charge. After the battery branch 110 with the lowest charge is fully charged, its charge increases, and the circuit disconnects. Then, another battery branch 110 with the lowest charge connects, and the drive unit 21 charges this battery branch 110 with the generated braking energy until the charges of all battery branches 110 are balanced.

[0245] Optionally, when the battery 11 includes multiple battery branches 110 connected in parallel, the battery thermal management module 15 may also include multiple thermal management branches connected in parallel. The number of thermal management branches may be the same as the number of battery branches 110 and correspond one-to-one. Each thermal management branch may perform temperature regulation (e.g., heating) on ​​the corresponding battery branch 110.

[0246] In the above technical solution, the driving unit 21 uses the generated braking energy to charge the battery branch 110 with the lowest charge first, which helps to achieve balance among multiple battery branches 110, improve the consistency of each battery branch 110, and ensure the service life of the battery 11.

[0247] In some embodiments, refer to Figure 2 The energy management system also includes a cooling fan 23, which is used to dissipate heat from the braking resistor 22. If the remaining charge of the battery 11 is greater than or equal to the preset charge, the battery charging and discharging circuit 3 does not work and the cooling fan 23 works.

[0248] For example, when the power equipment is in braking mode, the braking energy generated by the drive unit 21 can power the braking resistor 220 of the braking resistor 22. When the temperature of the battery 11 is greater than or equal to the first preset temperature, the battery 11 does not need to be heated, the thermal management unit 5 does not work, and the heat generated by the braking resistor is not transferred to the battery 11. Furthermore, when the remaining charge of the battery 11 is greater than or equal to the preset charge, the battery 11 does not need to be charged, and the battery charging and discharging circuit 3 does not work. At this time, the heat generated by the braking resistor 220 can be quickly dissipated by the cooling fan 23, and the braking resistor 220 can consume braking energy in the form of heat.

[0249] In the above technical solution, the cooling fan 23 works and dissipates heat from the braking resistor 22, which can help the braking resistor 22 consume braking energy, resulting in better heat dissipation. It can also prevent the temperature of the braking resistor 22 from getting too high, which would cause the ambient temperature to get too high and affect the service life of other surrounding components.

[0250] In some embodiments, determining whether the power device is in a braking state further includes: if the power device is not in a braking state, determining whether the temperature of the battery 11 is lower than a first preset temperature; if the temperature of the battery 11 is lower than the first preset temperature, controlling the electric heating circuit 4 to work to heat the battery 11.

[0251] When the power equipment is not in a braking state, the drive unit 21 does not generate braking energy. Since the battery 11 is electrically connected to the braking resistor 220 to form an electric heating circuit 4, the electric heating circuit 4 operates when the temperature of the battery 11 is lower than a first preset temperature. For example, the operation of the electric heating circuit 4 can be controlled by a button or program, and the thermal management unit 5 also operates. When the electric heating circuit 4 is operating, the battery 11 supplies power to the braking resistor 220, the braking resistor 220 heats up, and the heat is transferred to the battery 11 through the thermal management unit 5. For example, the heating resistor 220 heats up and the heat is transferred to the battery thermal management module 15 through the resistance heat exchange module 223. The battery thermal management module 15 exchanges heat with the battery 11, thereby regulating the temperature of the battery 11 to heat it.

[0252] For example, the power source can be a vehicle, and the vehicle is not in a braking state, which can include the following situations: for example, the vehicle is in normal driving and the vehicle is not braking; or for example, the vehicle is not started.

[0253] In the above technical solution, when the power equipment is not in a braking state, the heating circuit 4 is controlled according to the temperature of the battery 11 to meet the heating requirements of the battery 11 when the power equipment is not in a braking state, thereby ensuring that the battery 11 can be in the normal operating temperature range and ensuring the working performance of the battery 11.

[0254] In some embodiments, refer to Figure 3 The battery 11 includes multiple battery branches 110 connected in parallel, which control the operation of the electric heating circuit 4, including: the battery branch 110 with the largest power supply prioritizes power supply to the braking resistor 220.

[0255] Each battery branch 110 is connected in series with at least one battery cell 111, including the following situations: for example, each battery branch 110 is connected in series with one battery cell 111; or for example, each battery branch 110 is connected in series with multiple battery cells 111. One of the battery cells 111 may include one or more individual battery cells. Multiple individual battery cells can be connected in series, in parallel, or in a mixed connection to directly form a battery cell 111. A mixed connection means that multiple individual battery cells are connected in both series and parallel.

[0256] The charge and magnitude of each battery branch 110 can be obtained in the following ways: For example, battery 11 may also include a battery management system, which can measure the charge of each battery branch 110 and compare the magnitude of the charges of each battery branch 110. For example, the battery management system can measure the voltage of each battery branch 110. If the voltages of multiple battery branches 110 are inconsistent, then the charge of the multiple battery branches 110 is inconsistent.

[0257] For example, each battery branch 110 is connected in series with a control switch 61, which controls the control switch 61 according to the power levels of all battery branches 110.

[0258] For example, when the charge levels of the various battery branches 110 are inconsistent, the control switch 61 of the battery branch with the lowest charge can be disconnected, while the control switch 61 of the battery branch with the highest charge is kept in the connected state, thus ensuring that the battery branch with the highest charge is in the connected state. When the electric heating circuit 4 is working, the battery branch 110 with the highest charge supplies power to the braking resistor 220. The braking resistor 220 generates heat, which is transferred to the battery thermal management module 15 through the resistance heat exchange module 223. The battery thermal management module 15 then regulates the temperature of the battery 11.

[0259] For example, when the battery branch 110 with the largest charge supplies power to the braking resistor 220, the other battery branches 110 are in an open state. The braking resistor 220 can consume the charge of the battery branch 110 with the largest charge, and the battery branch 110 with the largest charge discharges through the braking resistor 220.

[0260] In the above technical solution, the battery branch 110 with the largest power supply prioritizes power supply to the braking resistor 220. This not only regulates the temperature of the battery 11, but also allows the battery branch 110 with the largest power supply to discharge through the braking resistor 220, which helps to achieve balance among multiple battery branches 110, improves the consistency of each battery branch 110, and ensures the service life of the battery 11.

[0261] The following reference Figures 1-4 The present invention describes an energy management system 100 for a power device and a control method thereof for the energy management system 100 according to some embodiments thereof.

[0262] In this embodiment, the energy management system 100 includes a braking resistor 220 and a thermal management unit 5. The thermal management unit 5 includes a battery thermal management module 15 and a resistance heat exchange module 223. The resistance heat exchange module 223 is thermally connected to or in thermal contact with the braking resistor 220, and the resistance value of the braking resistor 220 is adjustable. The battery thermal management module 15 and the resistance heat exchange module 223 are connected to form a thermal management loop 7 for the flow of heat exchange medium. The battery thermal management module 15 is used to regulate the temperature of the battery 11.

[0263] The power equipment has the aforementioned energy management system 100, and also includes a drive unit 21 and a battery 11. The drive unit 21 includes a drive motor and motor control components. The battery 11 is electrically connected to the drive unit 21 to form a battery charging and discharging circuit 3; the drive unit 21 is electrically connected to a braking resistor 220 to form a braking energy circuit 24; the braking resistor 220 has a first interface 221 and a second interface 222, the first interface 221 of the braking resistor 220 is electrically connected to the positive terminal of the battery 11, and the second interface 222 of the braking resistor 220 is electrically connected to the negative terminal of the battery 11. The battery 11 and the braking resistor 220 are electrically connected to form an electric heating circuit 4.

[0264] The resistance heat exchange module 223 includes a heat exchange tube, and the battery thermal management module 15 has a heat exchange channel. The resistance heat exchange module 223 has an outlet 225 and an inlet 224. The outlet 225 of the resistance heat exchange module 223 is connected to the inlet of the heat exchange channel, and the inlet 224 of the resistance heat exchange module 223 is connected to the outlet of the heat exchange channel. The heat exchange medium can circulate between the resistance heat exchange module 223 and the battery thermal management module 15. A circulation pump 13 is provided on the thermal management circuit 7. The circulation pump 13 can drive the heat exchange medium in the resistance heat exchange module 223 to flow into the battery thermal management module 15 through the outlet 225. The heat exchange medium exchanges heat with the battery 11 to regulate the temperature of the battery 11. After exchanging heat with the battery 11, the heat exchange medium flows back to the resistance heat exchange module 223 from the inlet 224 to continue exchanging heat with the braking resistor 220 and continue to circulate.

[0265] Battery 11 includes multiple battery branches 110 connected in parallel. Each battery branch 110 has multiple battery cells 111 connected in series, and each battery cell 111 includes one or more individual battery cells. Each battery branch 110 has two control switches 61 connected in series, and all battery cells 111 of each battery branch 110 are connected in series between the two control switches 61. The control switches 61 control the on / off state of the corresponding battery branch 110. The control switches 61 are relays, and the relays are located inside the high-voltage box 6.

[0266] Battery 11 also includes a battery management system, which is used to determine the charge of each battery branch 110 and the remaining charge of battery 11; the energy management system 100 also includes a cooling fan 23, which is used to dissipate heat from the braking resistor 22.

[0267] The control method of the energy management system 100 for power equipment is as follows:

[0268] Determine whether the power equipment is in a braking state;

[0269] If the power equipment is in a braking state, determine whether the temperature of the battery 11 is lower than the first preset temperature or whether the remaining charge of the battery 11 is lower than the preset charge.

[0270] If the power equipment is not in a braking state, determine whether the temperature of battery 11 is lower than the first preset temperature.

[0271] If the power equipment is in a braking state, determining whether the temperature of battery 11 is lower than a first preset temperature specifically includes the following steps:

[0272] If the temperature of battery 11 is lower than the first preset temperature, the braking energy circuit 24 and the thermal management unit 5 will work; if the temperature of battery 11 is greater than or equal to the first preset temperature, the thermal management unit 5 will not work.

[0273] When the temperature of battery 11 is lower than the first preset temperature, it is further determined whether the temperature of battery 11 is lower than the second preset temperature or whether the braking energy is lower than the first preset energy value.

[0274] Determining whether the temperature of battery 11 is lower than the second preset temperature includes the following steps:

[0275] If the temperature of battery 11 is lower than the second preset temperature, control the electric heating circuit 4 to work;

[0276] If the temperature of battery 11 is greater than or equal to the second preset temperature, the electric heating circuit 4 will not work.

[0277] Determining whether the braking energy is less than a first preset energy value includes the following steps:

[0278] If the braking energy is less than the first preset energy value, control the electric heating circuit 4 to work;

[0279] If the braking energy is greater than or equal to the first preset energy value, the electric heating circuit 4 will not work.

[0280] If the power equipment is in a braking state, determining whether the remaining charge of battery 11 is less than the preset charge includes the following steps:

[0281] If the remaining power of battery 11 is less than the preset power, the battery charging and discharging circuit 3 is controlled to work, and the driving unit 21 uses the braking energy generated to charge battery 11.

[0282] If the remaining charge of the battery 11 is greater than or equal to the preset charge, the battery charging and discharging circuit 3 will not operate.

[0283] If the vehicle is not in a braking state, determine whether the temperature of battery 11 is lower than the first preset temperature, specifically including the following steps:

[0284] If the temperature of battery 11 is lower than the first preset temperature, control the electric heating circuit 4 to work to heat battery 11;

[0285] If the temperature of battery 11 is greater than or equal to the first preset temperature, the electric heating circuit 4 will not work.

[0286] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0287] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. An energy management system for power equipment, characterized in that, include: A braking resistor, wherein the braking resistor is adapted to be electrically connected to the drive unit of the power equipment to form a braking energy circuit, and the braking resistor is adapted to be electrically connected to the battery of the power equipment to form an electric heating circuit; A thermal management unit, wherein the thermal management unit is used to heat the battery with the heat generated by the braking resistor; Specifically, when the power equipment is in a braking state, the braking energy circuit operates, and the thermal management unit is controlled according to the battery temperature. When the battery temperature is lower than a first preset temperature, the thermal management unit operates, and the electric heating circuit is controlled according to the battery temperature or the magnitude of the braking energy. When the battery temperature is lower than a second preset temperature or the braking energy is lower than a first preset energy value, the electric heating circuit operates, wherein the second preset temperature is lower than the first preset temperature. When the battery temperature is greater than or equal to the first preset temperature, the thermal management unit does not operate. When the power equipment is not in braking state, the electric heating circuit is controlled according to the temperature of the battery. When the temperature of the battery is less than a first preset temperature, the electric heating circuit and the thermal management unit are activated. The battery supplies power to the braking resistor to heat the battery. The battery includes multiple battery branches connected in parallel. When the electric heating circuit is activated, the battery branch with the largest charge first supplies power to the braking resistor. When the temperature of the battery is greater than or equal to the first preset temperature, the electric heating circuit and the thermal management unit are not activated.

2. The energy management system for power equipment according to claim 1, characterized in that, The thermal management unit includes a battery thermal management module and a resistance heat exchange module. The battery thermal management module and the resistance heat exchange module are connected to form a thermal management loop for the flow of heat exchange medium. The battery thermal management module is used to regulate the temperature of the battery. The resistance heat exchange module is thermally connected or in thermal contact with the braking resistor.

3. The energy management system for power equipment according to claim 1, characterized in that, The battery includes multiple battery branches connected in parallel, and each battery branch is connected in series with a control switch. The control switch is controlled according to the relationship between the charge levels of all the battery branches, so that the battery branch with the largest charge level is preferentially connected to the braking resistor to form the electric heating circuit.

4. The energy management system for power equipment according to claim 3, characterized in that, The battery branch includes at least one battery cell, and each battery branch has two control switches connected in series. All the battery cells in each battery branch are connected in series between the two control switches.

5. The energy management system for power equipment according to claim 1, characterized in that, The battery is adapted to be electrically connected to the drive unit to form a battery charging and discharging circuit.

6. The energy management system for power equipment according to claim 5, characterized in that, When the power equipment is in a braking state, the braking energy circuit operates first, and the driving unit uses the braking energy generated to heat the battery.

7. The energy management system for power equipment according to claim 5, characterized in that, When the power equipment is in a braking state, the battery charging and discharging circuit is controlled according to the remaining charge of the battery or the amount of braking energy generated by the drive unit.

8. The energy management system for power equipment according to claim 7, characterized in that, Controlling the battery charging and discharging circuit based on the remaining battery power includes: when the remaining battery power is less than a preset power, the battery charging and discharging circuit operates, and the drive unit uses the generated braking energy to charge the battery.

9. The energy management system for power equipment according to claim 8, characterized in that, The battery includes multiple battery branches connected in parallel, and the driving unit uses the braking energy generated to preferentially charge the battery branch with the lowest charge.

10. The energy management system for power equipment according to claim 7, characterized in that, It also includes a cooling fan for dissipating heat from the braking resistor; Controlling the battery charging and discharging circuit based on the remaining battery power includes: when the remaining battery power is greater than or equal to a preset power level, the battery charging and discharging circuit does not operate and the cooling fan operates.

11. The energy management system for power equipment according to claim 7, characterized in that, Based on the magnitude of the braking energy generated by the drive unit, the battery charging and discharging circuit is controlled, including: When the braking energy is less than the second preset energy value, the braking energy circuit operates and the battery charging and discharging circuit does not operate; when the braking energy is greater than or equal to the second preset energy value, both the braking energy circuit and the battery charging and discharging circuit operate.

12. The energy management system for power equipment according to claim 1, characterized in that, It also includes a cooling fan for dissipating heat from the braking resistor.

13. The energy management system for the power equipment according to any one of claims 1-12, characterized in that, The resistance value of the braking resistor is adjustable.

14. A power equipment, characterized in that, include: The energy management system according to any one of claims 1-13.

15. A control method for an energy management system of a power equipment, characterized in that, The energy management system includes a braking resistor and a thermal management unit. The braking resistor is adapted to be electrically connected to the drive unit of the power equipment to form a braking energy circuit. The braking resistor is adapted to be electrically connected to the battery of the power equipment to form an electric heating circuit. The thermal management unit is used to heat the battery with the heat generated by the braking resistor. The control method includes: Determine whether the power equipment is in a braking state; If the power equipment is in a braking state, determine whether the temperature of the battery is lower than a first preset temperature; If the temperature of the battery is lower than the first preset temperature, the braking energy circuit and the thermal management unit will operate.

16. The control method for the energy management system according to claim 15, characterized in that, If the temperature of the battery is lower than the first preset temperature, the braking energy circuit operates and the thermal management unit operates, including: Determine whether the temperature of the battery is lower than a second preset temperature, wherein the second preset temperature is lower than the first preset temperature; If the temperature of the battery is lower than the second preset temperature, the electric heating circuit is controlled to operate. If the temperature of the battery is greater than or equal to the second preset temperature, the electric heating circuit is controlled to not work.

17. The control method for the energy management system according to claim 15, characterized in that, If the temperature of the battery is lower than the first preset temperature, the braking energy circuit operates and the thermal management unit operates, including: Determine whether the braking energy is less than a first preset energy value; If the braking energy is less than the first preset energy value, the electric heating circuit is controlled to operate. If the braking energy is greater than or equal to the first preset energy value, the electric heating circuit is controlled to not work.

18. The control method for the energy management system according to claim 15, characterized in that, The battery is adapted to be electrically connected to the drive unit to form a battery charging and discharging circuit. If the power equipment is in a braking state, it is determined whether the remaining charge of the battery is less than a preset charge. If the remaining charge of the battery is less than the preset charge, the battery charging and discharging circuit is controlled to work, and the driving unit uses the braking energy generated to charge the battery. If the remaining charge of the battery is greater than or equal to the preset charge, the battery charging and discharging circuit is controlled to not work.

19. The control method for the energy management system according to claim 18, characterized in that, The battery includes multiple battery branches connected in parallel. Controlling the operation of the battery charging and discharging circuit includes: the drive unit preferentially charging the battery branch with the lowest charge using the braking energy generated.

20. The control method for the energy management system according to claim 18, characterized in that, The energy management system also includes a cooling fan for dissipating heat from the braking resistor. If the remaining charge of the battery is greater than or equal to the preset charge, the battery charging and discharging circuit does not work and the cooling fan works.

21. The control method for the energy management system according to claim 15, characterized in that, Determining whether the power equipment is in a braking state further includes: If the power equipment is not in a braking state, determine whether the temperature of the battery is lower than the first preset temperature; If the temperature of the battery is lower than the first preset temperature, the electric heating circuit is controlled to operate to heat the battery.

22. The control method for the energy management system according to claim 21, characterized in that, The battery includes multiple battery branches connected in parallel, and the operation of the electric heating circuit is controlled by the battery branch with the largest amount of power supply giving priority to supplying power to the braking resistor.

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