Power conversion device, energy storage system and electric equipment

Abstract

The invention relates to the technical field of energy storage systems, and provides a power conversion device, an energy storage system and electric equipment, the power conversion device is applied to the energy storage system, the power conversion device comprises a box body, and an output cabin and a power conversion control cabin are arranged in the box body; the output cabin is provided with a plurality of output connecting ports on a front panel of the box body, the power conversion control cabin comprises a power board, a plurality of inductors, an alternating current output board and a target printed circuit board, and the target printed circuit board is respectively connected with the power board, the plurality of inductors and the alternating current output board. The target printed circuit board is used for replacing a copper bar for connection, so that the space occupied by copper bar connection is reduced, the stacking design in the power conversion device can be more convenient, and the size of the power conversion device can be further reduced through the stacking design while the separation of a high-pressure cabin and a low-pressure cabin is ensured.

Description

Technical Field

[0001] The present application relates to the technical field of energy storage, and particularly to a power conversion device, an energy storage system, and an electrical equipment. Background Art

[0002] A power conversion device (PCS) realizes the bidirectional conversion between the DC power of a battery and the AC power of a power grid through a DC / AC bidirectional converter, and is used to support the switching between grid-connected / off-grid modes, so as to meet various requirements such as power grid frequency modulation, voltage regulation, and energy dispatching.

[0003] In the related art, due to the size limitation of the energy storage system, and since the battery cells occupy most of the space of the energy storage system, the size of the power conversion device is very small. Moreover, the internal copper bars of the power conversion device occupy a lot of internal space of the power conversion device, making it very difficult to layout other functional boards in the power conversion device. Summary of the Invention

[0004] Based on this, in view of the problems in the above background art, it is necessary to provide a power conversion device, an energy storage system, and an electrical equipment, which can at least use a target printed circuit board to replace the copper bars for the layout of internal components, not only reducing the internal space occupied by the copper bars, but also contributing to the multi-layer stacking design inside the power conversion device, and realizing the further reduction of the size and volume of the power conversion device through the multi-layer stacking design while ensuring the separation of the high-voltage and low-voltage compartments.

[0005] To solve the above technical problems and other problems, according to some embodiments, a first aspect of the present application provides a power conversion device applied to an energy storage system. An output compartment and a power conversion control compartment are provided in the box body of the power conversion device; the output compartment includes a plurality of output connection ports provided on the front panel of the box body, and the power conversion control compartment includes a target printed circuit board, a power board, a plurality of inductors, and an AC output board that are respectively connected to the target printed circuit board.

[0006] In some embodiments, the target printed circuit board is located above the plurality of inductors and is electrically connected to all the plurality of inductors; the AC output board is located above the target printed circuit board and is electrically connected to the target printed circuit board through copper posts.

[0007] In some embodiments, the output compartment includes an upper space and a lower space of the output compartment. The upper space of the output compartment includes a variety of high-voltage output devices, and the lower space of the output compartment is connected and communicated with the lower space of the power conversion control compartment; at the position corresponding to the lower space of the output compartment on the front panel of the box body, a plurality of first ventilation holes are provided; at the position corresponding to the lower space of the power conversion control compartment on the back panel of the box body, a plurality of second ventilation holes are provided; the plurality of first ventilation holes and the plurality of second ventilation holes are used for dissipating heat from the lower space of the output compartment and the lower space of the power conversion control compartment; among them, a plurality of inductors are located inside the lower space of the power conversion control compartment.

[0008] In some embodiments, the interconnected lower space of the output compartment and the lower space of the power conversion control compartment form an external air duct, and a first cooling fan group is provided in the lower space of the output compartment.

[0009] In some embodiments, a radiator is further provided in the lower space of the power conversion control compartment; the power board is located above the radiator and is electrically connected to the target printed circuit board.

[0010] In some embodiments, it further includes a plurality of current sampling Hall sensors located on the AC output board. The power board is electrically connected to the plurality of current sampling Hall sensors, and the current sampling Hall sensors are electrically connected to a plurality of DC output terminals of the target printed circuit board.

[0011] In some embodiments, the power conversion device further includes a control board located in the power conversion control compartment; the plurality of current sampling Hall sensors are respectively electrically connected to the control board and transmit the detected plurality of current data to the control board, and the control board is used to protect the power conversion device according to the plurality of current data.

[0012] In some embodiments, the control board is used to perform the following steps: calculate the chopped wave power output by the power board according to the current data detected by the current sampling Hall sensors; determine whether there is an abnormality in the insulated gate bipolar transistor group corresponding to the current sampling Hall sensors according to the chopped wave power output by the power board.

[0013] In some embodiments, the target printed circuit board includes a plurality of inductor connection points; the inductor connection points are electrically connected to a corresponding inductor.

[0014] In some embodiments, the target printed circuit board further includes a plurality of input connection points; the input connection points are connected to the output connection points of a corresponding power board, and the input connection points are also connected to the corresponding inductor connection points through the printed circuits on the target printed circuit board.

[0015] In some embodiments, the target printed circuit board further includes a plurality of output connection points; the output connection points are connected to the input connection points of the corresponding AC output board, and the output connection points are also connected to the corresponding inductance connection points through printed circuits on the target printed circuit board.

[0016] In some embodiments, a second cooling fan group is further included, and the second cooling fan group is located at a position on the backplane corresponding to the upper space of the power conversion control cabin; wherein, a plurality of third ventilation holes are provided at a position on the front panel corresponding to the upper space of the power conversion control cabin, and the plurality of third ventilation holes and the second cooling fan group are used to form a cooling air duct in the upper space of the power conversion control cabin.

[0017] In some embodiments, a second aspect of the present application provides an energy storage system, including a battery pack, a management subsystem, a thermal management system, and the power conversion device in any of the above embodiments.

[0018] In some embodiments, a third aspect of the present application provides an electrical device, including the power conversion device in any of the above embodiments.

[0019] In the power conversion device, energy storage system and electrical device of the above embodiments, by using a target printed circuit board instead of a copper busbar for internal component layout, not only reduces the internal space occupied by the copper busbar, but also helps the internal multi-layer stacking design of the power conversion device, realizing that under the condition of ensuring the separation of high-voltage and low-voltage cabins, the size and volume of the power conversion device are further reduced through the multi-layer stacking design.

[0020] Moreover, it avoids the occlusion of the copper busbar, facilitates the formation of a cooling air duct, and while reducing the size and volume of the power conversion device, can also improve the heat dissipation performance of the power conversion device. Description of the Drawings

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0022] Figure 1 It is a schematic diagram of the power conversion device provided in an embodiment of the present application;

[0023] Figure 2 It is a schematic diagram of the existing power conversion device provided in an embodiment of the present application;

[0024] Figure 3 It is a schematic diagram of the target printed circuit board provided in an embodiment of the present application.

[0025] Description of reference numerals:

[0026] 101. Box; 102. Power board; 103. Copper pillar; 104. AC output board; 105. Second cooling fan group; 106. Inductor; 107. Target printed circuit board; 108. Insulated gate bipolar transistor group; 109. Heat sink; 110. First cooling fan group; 201. Copper busbar; 301. Copper pillar connection point; 302. Connecting copper wire; 303. Inductor connection point. DETAILED DESCRIPTION

[0027] In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0029] In the case of using “including”, “having”, and “comprising” described herein, another component may be added unless a clear limiting term such as “only”, “consisting of”, etc. is used. Unless mentioned otherwise, a term in the singular form may include a plural form and should not be understood as being one in number.

[0030] It should be understood that although the terms "first", "second", etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element without departing from the scope of the present application.

[0031] In this application, unless otherwise clearly specified and limited, the terms "connected", "connection" and the like should be understood in a broad sense, for example, it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0032] As a key component of the energy storage system, the power conversion device (PCS) faces challenges in design due to space constraints. The power conversion device realizes the energy interaction between the battery and the power grid through DC / AC bidirectional conversion technology and has the function of seamless switching between grid-connected and off-grid modes. Since the internal space of the energy storage system is mainly occupied by battery cells, the installation space of the power conversion device is significantly compressed, resulting in a highly compact layout of its internal components. This space limitation poses higher requirements for heat dissipation design, maintenance convenience, and reliability. Moreover, due to the arrangement of copper bars in the power conversion device, a considerable part of the space in the power conversion device is occupied, making it very difficult to layout other functional boards in the power conversion device.

[0033] Please refer to Figure 2 , Figure 2 As a comparative example of this application, a schematic diagram of a power conversion device is shown.

[0034] In some embodiments, as Figure 2 shown, the inductor 106 of the power conversion device is connected to the power board 102 and the AC output board 104 through copper bars 201. Since the shape and connection position of the copper bars 201 need to correspond to the position of the output connection points of the inductor 106, the copper bars 201 occupy a large amount of space. For example, the copper bar 201 connecting the inverter inductor 106 and the AC output board 104 occupies most of the space above the inverter inductor 106, making it impossible to arrange other functional boards in this space. They can only be stacked above and below the AC output board 104 or occupy the position of the output compartment between the AC output board 104 and the front panel (not shown in the figure), resulting in an overly dense arrangement of multiple functional boards in the power conversion device. Moreover, due to insufficient space in the power conversion control compartment and the large number of functional boards that need to be arranged in the power conversion control compartment, the functional boards in the power conversion control compartment will intrude into the output compartment, causing the output compartment and the power conversion control compartment to intersect, and further leading to problems of mutual influence between the high- and low-voltage components in the output compartment and the power conversion control compartment.

[0035] Please continue to refer to Figure 2 , the inductor 106 is also connected to the power output board through copper bars 201. Since the shape and connection position of the copper bars 201 need to correspond to the position of the input connection points of the inductor 106, and the copper bars 201 also require a certain routing path and assembly redundancy, the copper bars 201 between the inductor 106 and the power output board not only occupy height space but also require a part of the length space, resulting in the need to increase the length of the box 101 of the power conversion device or conduct more dense device stacking. And more dense device stacking will further cause the devices to be unable to dissipate heat effectively. The increased cooling fans will have a significant reduction in ventilation efficiency due to the blockage of the copper bars 201.

[0036] In some embodiments, the present application provides a power conversion device. Refer to Figure 1 - Figure 2 , the power conversion device includes: a box body 101, wherein an output compartment and a power conversion control compartment are arranged inside the box body 101.

[0037] The output compartment is formed with a plurality of output connection ports on the front panel of the box body 101. The power conversion control compartment includes a power board 102, a plurality of inductors 106, an AC output board 104, and a target printed circuit board (PCB) 107. The target printed circuit board 107 is respectively connected to the power board 102, the plurality of inductors 106, and the AC output board 104.

[0038] Exemplarily, the output compartment is a high-voltage compartment, and the power conversion control compartment is a low-voltage compartment. In this way, after using the target printed circuit board 107 to replace the copper busbar 201, the power board 102, the plurality of inductors 106, the AC output board 104, and the target printed circuit board 107 can be stacked, avoiding the power conversion control compartment squeezing the space of the output compartment, and forming a partition layout design with separation of the high-voltage and low-voltage compartments of the output compartment and the power conversion control compartment.

[0039] Exemplarily, the output compartment may include high-voltage components on the DC side, high-voltage components on the AC side, reactive power compensation boards, DC lightning protection and fuse protection boards, high-voltage switch and circuit breaker assemblies, power semiconductor devices, etc. Among them, the high-voltage components on the DC side include DC busbars, DC support capacitors, DC filter inductors, etc. The DC busbar can be made of low-resistance copper or aluminum bars, with multiple layers of insulating layers (such as epoxy resin coatings) superimposed, used to connect the battery cluster and the power conversion device, and can carry a DC voltage of 1000V - 1500V. In a three-level topology, it is necessary to achieve intermediate voltage balance control. The DC support capacitor can be a thin-film capacitor (which can improve the ability to withstand high-ripple current) or an electrolytic capacitor (suitable for low-cost solutions), which can suppress DC side voltage fluctuations, absorb high-frequency harmonics, and provide transient current buffering at the instant of Insulate-Gate Bipolar Transistor (IGBT) switching. The DC filter inductor can be wound with a ferromagnetic alloy core, and the inductance value of the DC filter inductor is adjusted according to the power demand. The high-voltage components on the AC side include inverter power units, step-up transformers, etc. The inverter power unit can be composed of two-level, three-level or multi-level topology structures. The step-up transformer can be a power frequency transformer, a high-frequency transformer, etc., which can boost the voltage of the low-voltage alternating current output by the power conversion device to match the grid connection requirements. The power semiconductor device can be an IGBT module or a MOSFET module, etc. The IGBT module can be composed of an IGBT chip, a drive circuit, a heat dissipation substrate, etc., and can adopt a multi-level packaging structure. The Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) module has a breakdown voltage rating of over 1700V, supports a higher switching frequency (with a 30% lower loss than the IGBT), and is more suitable for the high-frequency trend of the energy storage system. The reactive power compensation board is used to dynamically adjust the reactive power, optimize the power factor on the grid side, and is suitable for high-voltage dynamic reactive power compensation and improving the power transmission efficiency. The DC lightning protection and fuse protection board is used to prevent damage to the internal circuit of the high-voltage compartment caused by overvoltage or short circuit. The high-voltage switch and circuit breaker assembly includes AC circuit breakers (such as U / V / W phase circuit breakers) and DC disconnectors, etc., to achieve on / off control and fault isolation of the high-voltage circuit.

[0040] As an example, with multiple layers of insulating layers (such as epoxy resin coatings) superimposed, the DC voltage that can be carried can be 1000V, 1300V, 1500V, etc.

[0041] Here, it should be noted that the power conversion device proposed in this application is applied to an energy storage system. In the energy storage system, there is also a battery pack, a battery management system for managing the battery pack, and a fire protection system, etc.

[0042] As an example, the battery pack is placed in the battery room of the energy storage system, and the placement location and quantity of the battery pack can be set according to actual requirements. The battery pack can store the electric energy of the power grid during the low electricity consumption period and supply power to external electrical equipment during the high electricity consumption period, so as to achieve peak shaving and valley filling of electric energy and meet the power supply requirements in seasonal regions. The power conversion device is placed in the equipment room and is electrically connected to the battery pack, and is used to adjust the output voltage, frequency, phase number, and other electrical parameters when the battery pack outputs electric energy to ensure the power supply of the battery pack to external electrical equipment; the battery management system is used to manage the battery pack. Specifically, the battery management system can include an electric cabinet, which is placed in the equipment room and is electrically connected to the battery pack to manage the charging and discharging process of the battery pack, such as monitoring the charging and discharging voltage of the battery pack, etc.; the battery management system can also include temperature sensors and the like arranged on the battery pack to monitor the temperature of the battery pack and ensure the safe and reliable operation of the battery pack; the fire protection system is used to take corresponding fire extinguishing measures when a fire is detected. It can be understood that the specific installation location of the fire protection system can be determined according to actual needs. To ensure the safe operation of the micro energy storage system, the fire protection system can also be installed in the battery room, or the fire protection system can be installed in both the equipment room and the battery room.

[0043] As an example, the fire protection system can include devices such as temperature sensors, smoke sensors, automatic fire extinguishers, and controllers. The controller is respectively connected to the temperature sensor, the smoke sensor, and the automatic fire extinguisher, so as to be able to judge whether a fire has occurred based on the temperature sensed by the temperature sensor and the smoke sensed by the smoke sensor, and when it is judged that a fire has occurred, control the automatic fire extinguisher to automatically spray the fire extinguishing agent to achieve fire extinguishing. The partition between the battery room and the equipment room can be made of fireproof materials. When a fire occurs in the battery room or the equipment room, it can effectively block the spread of the fire and confine the fire within the battery room or the equipment room, so as to effectively reduce equipment losses and lower the fire risk level, and win precious time for rescue.

[0044] Optionally, the energy storage system may further include a monitoring system, which may include at least one of an acoustic-optical alarm, a deflation indicator light, an exhaust mechanism, and a pressure relief mechanism. The acoustic-optical alarm may be disposed outside the energy storage system. The acoustic-optical alarm may emit a warning signal in the form of sound and / or light when an emergency such as a fire occurs in the energy storage system, reminding the staff to handle it in time. The deflation indicator light may be disposed outside the energy storage system. A certain amount of hydrogen is generated during the charge and discharge process of the battery pack. When the hydrogen concentration in the energy storage system reaches a certain level, the deflation indicator light will emit a warning signal such as sound and / or light, reminding the staff to perform hydrogen exhaust and deflation operations on the energy storage system, thereby ensuring the safety of the energy storage system operation. The exhaust mechanism may be used to perform hydrogen exhaust and deflation operations on the energy storage system. The exhaust mechanism may include an exhaust fan, and when hydrogen exhaust and deflation operations are required, the exhaust fan is turned on manually or automatically.

[0045] Specifically, please refer to Figure 1 , the target printed circuit board 107 is located above the plurality of inductors 106 and is electrically connected to the plurality of inductors 106; the AC output board 104 is located above the target printed circuit board 107 and is electrically connected to the target printed circuit board 107 through the copper posts 103.

[0046] Specifically, please continue to refer to Figure 1 , a stacked arrangement is formed among the plurality of inductors 106, the target printed circuit board 107, and the AC output board 104, and they are interconnected through the copper posts 103. Compared with the technical solution of using the copper busbar 201 to connect between the plurality of inductors 106 and the AC output board 104, a large amount of space is saved.

[0047] Among them, the target printed circuit board 107 includes a plurality of inductor connection points 303, a plurality of input connection points, and a plurality of output connection points; the positions of the plurality of inductor connection points 303 correspond to the connection positions of the plurality of inductors 106, and each inductor connection point 303 is electrically connected to the wiring position of a corresponding inductor 106.

[0048] Among them, each input connection point is connected to the output connection point of a corresponding power board 102 through the copper post 103, and each input connection point is also connected to a corresponding inductor connection point 303 through the printed circuit on the target printed circuit board 107.

[0049] Among them, each output connection point is connected to the input connection point of a corresponding AC output board 104 through the copper post 103, and each output connection point is also connected to a corresponding inductor connection point 303 through the printed circuit on the target printed circuit board 107.

[0050] As an example, please refer to Figure 3, a plurality of inductance connection points 303 are formed on the target printed circuit board 107, and each inductance connection point 303 is electrically connected to a corresponding input connection point and output connection point of the inductor 106.

[0051] Please continue to refer to Figure 3 , the target printed circuit board 107 further includes copper pillar connection points 301, and the copper pillar connection points 301 form an electrical connection with the inductor 106 through the circuit layout on the target printed circuit board 107, so that the target printed circuit board 107 achieves the effect of replacing the copper busbar 201.

[0052] Please continue to refer to Figure 3 , on the target printed circuit board 107, connection copper wires 302 are also printed. Here, on the target printed circuit board 107, using the connection copper wires 302 to connect the inductor 106 and the copper pillar 103 can not only meet the requirements of high conductivity and stability of the power conversion device, but also avoid the heating risk caused by using other conductive materials for electrical connection.

[0053] Please continue to refer to Figure 1 and Figure 3 , wherein, the setting positions of the plurality of inductance connection points 303, the plurality of input connection points and the plurality of output connection points respectively correspond to the positions of the plurality of inductors 106, the positions of the output connection points of the power board 102, and the positions of the input connection points of the AC output board 104, ensuring that the connection between the stacked AC output board 104, the target printed circuit board 107 and the plurality of inductors 106 is still an electrical connection formed through the medium of copper. There is no need to set the complex shape of the copper busbar 201, and only the copper pillar 103 is needed to complete the connection of the stacked AC output board 104, the target printed circuit board 107 and the plurality of inductors 106. Connecting with the power board 102 through the copper pillar 103 not only ensures the stability of the electrical connection, but also reduces the occupied space volume.

[0054] Specifically, the output cabin includes an upper output cabin space and a lower output cabin space.

[0055] Specifically, the upper output cabin space includes a variety of high-voltage output devices.

[0056] Here, it should be noted that in the related art, due to the fact that the copper busbar 201 occupies most of the space of the power conversion control cabin and the size requirements of the power conversion device, the functional boards such as the power board 102 and the AC output board 104 are very likely to invade the cabin of the value output cabin, and the mixed setting of the high- and low-voltage cabins will significantly increase the system complexity, causing problems such as efficiency loss, increased failure rate and safety risks, resulting in relatively large system hidden dangers.

[0057] In some embodiments, the output compartment includes an upper space and a lower space of the output compartment. The upper space of the output compartment includes a variety of high-voltage output devices, and the lower space of the output compartment is connected to the lower space of the power conversion control compartment; at the position corresponding to the lower space of the output compartment on the front panel of the box body, a plurality of first ventilation holes are provided; at the position corresponding to the lower space of the power conversion control compartment on the back panel of the box body, a plurality of second ventilation holes are provided; the plurality of first ventilation holes and the plurality of second ventilation holes are used for dissipating heat from the lower space of the output compartment and the lower space of the power conversion control compartment.

[0058] In some embodiments, a plurality of inductors are located inside the lower space of the power conversion control compartment.

[0059] Please refer to Figure 1 , in some embodiments, a plurality of inductors 106 are located in the lower space of the power conversion control compartment.

[0060] Specifically, the mutually connected lower space of the output compartment and the lower space of the power conversion control compartment form an external air duct, and a first cooling fan group 110 is arranged in the lower space of the output compartment.

[0061] In this way, using the target printed circuit board 107 to replace the copper busbar 201 avoids the blockage of the copper busbar 201 to the cooling air. Arranging a plurality of inductors 106 in the lower space of the power conversion control compartment increases the heat dissipation capacity of the plurality of inductors 106.

[0062] It should be noted that the inductor 106 undertakes the functions of current filtering and energy storage in the power conversion device, but when the alternating current passes through the inductor 106, copper loss (conductor resistance loss) and iron loss (magnetic core eddy current loss) will be generated, resulting in device temperature rise. If the inductor 106 cannot be effectively cooled, the loss of the inductor 106 will increase significantly, reducing the overall power conversion efficiency of the PCS. Therefore, in this application, the inductor 106 is arranged in the external air duct to ensure the heat dissipation efficiency of the inductor 106.

[0063] Specifically, please continue to refer to Figure 1 , a radiator 109 is also arranged in the lower space of the power conversion control compartment.

[0064] Among them, the power board 102 is located above the radiator 109 and is electrically connected to the target printed circuit board 107 through copper posts 103.

[0065] Here, it should be noted that various power devices such as insulated gate bipolar transistors and MOSFETs provided on the power board 102 will generate a large amount of heat during the power conversion process. Therefore, in this embodiment, the power board 102 is disposed on the radiator 109, and the radiator 109 is used to intensively dissipate heat from the power board 102. The radiator 109 is disposed in the lower air duct and directly contacts the external cooling air, ensuring the heat dissipation efficiency of the radiator 109 to further improve the heat dissipation effect on the power board 102.

[0066] Among them, the radiator 109 adopts a fin structure to increase the heat dissipation area, and optimizes the heat dissipation performance by adjusting parameters such as the height, thickness, and width of the fins. The first cooling fan group can cooperate with the radiator to form forced convection to achieve uniform temperature distribution. The radiator can be made of heat-conducting metals such as aluminum or copper, and the heat dissipation surface area is enlarged through the fin structure.

[0067] Here, since the use of copper bars in the power conversion device is avoided, the embodiment of the present application can form a lower air duct at the positions where multiple inductors are located, and the lower air duct is directly in contact with the external air, so that the cooling air flowing into the external air duct does not pass through other components, which not only ensures the cooling effect of the radiator on multiple insulated gate bipolar transistor groups, but also ensures the cooling effect of the radiator on multiple inductors.

[0068] Among them, multiple inductors can be arranged in parallel or staggered. The long axes of the inductors arranged in parallel should be parallel to the direction of the forced air flow to reduce the air flow resistance and increase the flow rate. This design can make the air flow form a laminar flow along the surface of the inductor, enhancing the convective heat transfer efficiency. When using finned inductors and arranging them axially in parallel, the wind speed loss can be reduced by 15%-20%; when using staggered arrangement optimization, the multi-inductor array can adopt a 45°-60° staggered layout. By destroying the air flow boundary layer and enhancing the turbulent effect, the heat transfer coefficient can be increased by 8%-12%.

[0069] Optionally, a temperature detection device can also be provided near the inductor, and both the temperature detection device and the fan are connected to the control board. The control board can dynamically adjust the fan speed according to the real-time temperature of the inductor.

[0070] Specifically, please refer to Figure 1 , the power conversion device further includes a second cooling fan group 105.

[0071] Among them, the second cooling fan group 105 is located at a position on the back panel corresponding to the upper space of the power conversion control cabin. A plurality of third ventilation holes are formed at a position on the front panel corresponding to the upper space of the power conversion control cabin, and the plurality of third ventilation holes are used to form a cooling air duct in the upper space of the power conversion control cabin.

[0072] Here, since the present application avoids the use of copper bars, there will be no obstruction to the cooling air of the cooling air duct in the upper space; since there is a larger space for setting function boards, the gaps between multiple function boards are also larger, which is more convenient for the circulation of cooling air.

[0073] In this way, since the target printed circuit board 107 is used to replace the copper bar 201, the obstruction of the copper bar 201 to the cooling air is avoided. Through the stacking design, and using the copper posts 103 to electrically connect the power board 102, the AC output board 104 and the target printed circuit board 107, it can be ensured that when the power board 102, the AC output board 104 and the target printed circuit board 107 are stacked, there is a certain distance between the power board 102, the AC output board 104 and the target printed circuit board 107. In this way, by forming a cooling air duct in the upper space of the power conversion control cabin, the power board 102, the AC output board 104 and the target printed circuit board 107 can be effectively cooled.

[0074] As an example, please refer to Figure 1 , the power conversion device further includes a power supply board and a secondary power supply board, etc. The power supply board is used to supply power to function boards such as the control board and the power board 102, and the secondary power supply board is used to supply power to the first cooling fan group and the second cooling fan group 105. The power supply board and the secondary power supply board are both low-voltage boards and are arranged in the power conversion control cabin.

[0075] Specifically, please continue to refer to Figure 1 , the power conversion device further includes a plurality of current sampling Hall sensors (not shown in the figure).

[0076] Among them, a plurality of current sampling Hall sensors (not shown in the figure) are located on the AC output board 104. The power board 102 is connected to one end of the plurality of current sampling Hall sensors through a plurality of copper posts 103, and the Hall sensors are connected to a plurality of DC output terminals of the target printed circuit board 107 through the copper posts 103.

[0077] Specifically, please continue to refer to Figure 1 , the power conversion device further includes a control board, and the control board is located in the power conversion control cabin.

[0078] Among them, a plurality of current sampling Hall sensors are respectively electrically connected to the control board and transmit the detected plurality of current data to the control board. The control board is used to protect the power conversion device according to the current data.

[0079] Here, the Hall sensor is used to detect the output current of the power board 102 and transmit the data to the control board in real time. When the current exceeds the threshold, the control board can immediately trigger a protection mechanism (such as cutting off the drive signal of the insulated gate bipolar transistor) to prevent device overload damage. The Hall effect induces current through a magnetic field, without directly accessing the main circuit, avoiding the additional loss and insulation risk brought by the sampling resistor.

[0080] Further, please continue to refer to Figure 1 , the output signal of the current sampling Hall sensor (not shown in the figure) is directly connected to the target printed circuit through the copper column 103, reducing the long-distance transmission noise. In the related art, since the copper busbar 201 needs to form connections between the inductor 106, the power board 102, and the AC output board 104, its shape and orientation are fixed, and it has blocked the cooling air of multiple functional boards, making it difficult to set up another copper busbar 201 to detect current data. In the related power conversion device, since the copper busbar 201 occupies most of the space, the control board needs to be set at the position of the output cabin far from the power board 102 and is not directly connected to the AC output board 104.

[0081] Specifically, the control board is specifically used to perform the following steps: for each current sampling Hall sensor, calculate a chopped-wave power output by the power board 102 according to the current data detected by the current sampling Hall sensor; for each current sampling Hall sensor, determine whether the insulated gate bipolar transistor group 108 corresponding to the current sampling Hall sensor is abnormal according to a chopped-wave power output by the power board 102.

[0082] Exemplarily, please continue to refer to Figure 1 , when the control board determines that a certain insulated gate bipolar transistor group 108 is abnormal, the control board can disconnect the connection between the abnormal insulated gate bipolar transistor group 108 and the corresponding DC-side and AC-side power supplies. Generally, one insulated gate bipolar transistor group 108 corresponds to one battery pack. After disconnecting the connection between the abnormal insulated gate bipolar transistor group 108 and the corresponding DC-side and AC-side power supplies, the energy storage system can still operate normally.

[0083] Optionally, the power conversion device further includes an LC filter module. The LC filter module includes multiple filter capacitors and multiple filter inductors. Among them, the filter inductors and filter capacitors can filter out the battery double-frequency current and ripple fluctuations, and the filter inductors and filter capacitors are devices with low failure rates and high service lives and are not prone to failure. However, the mass of the filter inductors is relatively large, and the installation spacing between multiple filter inductors should not be too close.

[0084] In a possible implementation manner, one side of the LC filter module is connected to the AC-DC power conversion module, and the other side is connected to the battery high-voltage box.

[0085] Optionally, the front panel of the box body is provided with a PCS AC interface positive pole, a PCS AC interface negative pole, a low-voltage 15V test terminal, a battery high-voltage box positive pole, a battery high-voltage box negative pole, a data transmission network port, a secondary control cable interface, a communication indicator light, a bypass contactor on-off switch, an optical fiber communication interface, a high-voltage test terminal, and so on.

[0086] Among them, the positive and negative poles of the PCS AC interface are respectively connected to the positive and negative of the bypass contactor inside; externally, they are used to connect in series with the positive and negative poles of the PCS AC interface of another high-voltage cascaded energy storage converter device; the positive and negative poles of the PCS AC interface are used to connect the single voltage of the AC-DC power conversion module in series to achieve medium and high-voltage access; the low-voltage 15V test terminal is connected to the PMC board. Before the device is connected to high voltage, the board is powered on by an external device, and the device status on the board can be observed and read; under low-voltage conditions, the PMC board is powered on to test and read the working performance of the module; the high-voltage test terminal is connected to the energy storage capacitor bank. Before the device is powered on, the DC energy storage capacitor bank can be powered by an external voltage source, and the AC-DC power conversion module can be powered on through the high-voltage test terminal to test the module performance; the on-off switch of the bypass contactor serves as the operation port of the bypass contactor, which is used to realize the self-bypass function of the module and to automatically disconnect the bypass in case of bypass failure. After the module is repaired, manual reset is required; the optical fiber communication interface belongs to the interface of the PMC board. After connecting the optical fiber, the PMC signal is uploaded to the background of the control cabinet through the optical signal, or the background control instruction is sent to the PMC board; the energy storage batteries on the battery cluster are connected in series and then connected to the positive and negative poles of the battery high-voltage box; the data transmission network port can upload the data monitored by the high-voltage box to the background control cabinet through the 485 network cable for remote control of the device. The voltage, current, temperature and other parameters of the energy storage system are monitored by the battery high-voltage box and these information are transmitted to the control system. By monitoring these parameters, abnormal situations in the system can be detected in time and corresponding measures can be taken for treatment; the secondary control cable interface is connected to the energy storage battery. When abnormal current and voltage occur in the system, the circuit can be cut off in time to protect the safety of the energy storage system and other electrical equipment. The communication indicator light is electrically connected to the battery high-voltage box and is used to display the device status information monitored by the battery high-voltage box to observe the operation status of the device. Generally, red indicates a fault and green indicates normal operation.

[0087] Specifically, the housing may include a structural skeleton, a front panel, a right side panel, a left side panel, a rear ventilation panel, a top cover plate, etc. The structural skeleton can be welded by standard profiles and is used to support internal components to ensure the structural strength of the device. Lifting interfaces are designed on the skeleton, and the lifting interfaces include lifting mechanisms. The skeleton, front panel, right side panel, left side panel, rear ventilation panel, and top cover plate are all made of metal materials to form the equipment protection housing.

[0088] Please refer to Figure 1, in some embodiments, the control board further includes a signal transmission unit (not shown in the figure). The signal transmission unit (not shown in the figure) can be connected to the alarm device of the energy storage system in a wired or wireless manner. When the control board determines that a certain insulated gate bipolar transistor group 108 is abnormal, it can control the signal transmission unit to transmit an indication signal that the insulated gate bipolar transistor group 108 is abnormal to the alarm device, so as to facilitate the staff to repair and replace the abnormal insulated gate bipolar transistor group 108.

[0089] In some embodiments, when a certain insulated gate bipolar transistor group 108 is abnormal, the control board can isolate the battery pack corresponding to the insulated gate bipolar transistor group 108 outside the normal battery pack, and transmit the power of the abnormal battery pack to the normal battery pack through the control board.

[0090] The above power conversion device, by using the target printed circuit board 107 instead of the copper busbar 201 for connection, not only reduces the space occupied by the connection of the copper busbar 201, but also enables a more convenient stacking design in the power conversion device. While ensuring the separation of the high-voltage and low-voltage compartments, through the stacking design, the size of the power conversion device can be further reduced.

[0091] Without the obstruction of the copper busbar 201, it is convenient to form a cooling air duct. While reducing the size of the power conversion device, it is also convenient for the power conversion device to dissipate heat.

[0092] In an exemplary embodiment, an energy storage system is provided, including a battery pack, a management subsystem, a thermal management system, and the power conversion device in any of the above embodiments.

[0093] In an exemplary embodiment, an electrical device is provided, and the electrical device includes the power conversion device in any of the above embodiments.

[0094] Please note that the above embodiments are for illustrative purposes only and do not imply any limitation to the present application.

[0095] Each embodiment in this specification is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. For the same or similar parts among the embodiments, reference can be made to each other.

[0096] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0097] The above embodiments only represent several implementation manners of the present application. The description thereof is relatively specific and detailed, but it should not be construed as a limitation to the scope of the patent application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application.

Claims

1. A power conversion device, characterized in that, Applied to an energy storage system, an output compartment and a power conversion control compartment are arranged inside the box body of the power conversion device; The output compartment includes a plurality of output connection ports arranged on the front panel of the box body, and the power conversion control compartment includes a target printed circuit board, a power board, a plurality of inductors, and an AC output board respectively connected to the target printed circuit board.

2. The power conversion device according to claim 1, characterized in that The target printed circuit board is located above the plurality of inductors and is electrically connected to all the plurality of inductors; The AC output board is located above the target printed circuit board and is electrically connected to the target printed circuit board through copper posts.

3. The power conversion device according to claim 1, characterized in that, The output compartment includes an upper space and a lower space of the output compartment. The upper space of the output compartment includes a variety of high-voltage output devices. The lower space of the output compartment is communicated with the lower space of the power conversion control compartment. At the position of the front panel of the box body corresponding to the lower space of the output compartment, a plurality of first ventilation holes are provided. At the position of the back panel of the box body corresponding to the lower space of the power conversion control compartment, a plurality of second ventilation holes are provided. The plurality of first ventilation holes and the plurality of second ventilation holes are used for dissipating heat from the lower space of the output compartment and the lower space of the power conversion control compartment; Wherein, the plurality of inductors are located inside the lower space of the power conversion control compartment.

4. The power conversion device according to claim 3, characterized in that, The mutually communicated lower space of the output compartment and the lower space of the power conversion control compartment form an external air duct, and a first cooling fan group is arranged inside the lower space of the output compartment.

5. The power conversion device according to claim 3, wherein A radiator is further arranged inside the lower space of the power conversion control compartment; the power board is located above the radiator and is electrically connected to the target printed circuit board.

6. The power conversion device according to claim 5, characterized in that, It further includes a plurality of current sampling Hall sensors located on the AC output board. The power board is electrically connected to the plurality of current sampling Hall sensors, and the current sampling Hall sensors are electrically connected to a plurality of DC output terminals of the target printed circuit board.

7. The power conversion device according to claim 6, wherein The power conversion device further includes a control board located inside the power conversion control compartment; The plurality of current sampling Hall sensors are respectively electrically connected to the control board and transmit the detected plurality of current data to the control board, and the control board is used to protect the power conversion device according to the plurality of current data.

8. The power conversion device according to claim 7, characterized in that, The control board is used to execute the following steps: Calculate the sealed wave power output by the power board according to the current data detected by the current sampling Hall sensor; Determine whether there is an abnormality in the insulated gate bipolar transistor group corresponding to the current sampling Hall sensor according to the sealed wave power output by the power board.

9. The power conversion device according to claim 1, characterized in that The target printed circuit board includes a plurality of inductor connection points; The inductor connection point is electrically connected to a corresponding inductor.

10. The power conversion device according to claim 9, characterized in that, The target printed circuit board further includes a plurality of input connection points; the input connection points are connected to the output connection points of a corresponding power board, and the input connection points are further connected to the corresponding inductor connection points through printed circuits on the target printed circuit board.

11. The power conversion device according to claim 9, characterized in that, The target printed circuit board further includes a plurality of output connection points; the output connection points are connected to the input connection points of the corresponding AC output board, and the output connection points are also connected to the corresponding inductor connection points through the printed circuits on the target printed circuit board.

12. The power conversion device according to claim 3, wherein, It further includes a second cooling fan group, and the second cooling fan group is located at a position on the backplane corresponding to the upper space of the power conversion control cabin; Wherein, a plurality of third ventilation holes are provided at a position on the front panel corresponding to the upper space of the power conversion control cabin, and the plurality of third ventilation holes and the second cooling fan group are used to form a cooling air duct in the upper space of the power conversion control cabin.

13. An energy storage system, characterized in that, Comprising: A battery pack; A management subsystem; A thermal management system; The power conversion device according to any one of claims 1 to 12.

14. An electrical equipment, characterized in that, Comprising the power conversion device according to any one of claims 1 to 12.

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