Power converter

Abstract

The invention relates to the technical field of power equipment, and discloses a power converter which comprises a shell, a radiator, a power device, a heat insulation layer and an insulation heat conduction layer. The radiator comprises a substrate and a plurality of radiating fins; the substrate is installed and fixed on the shell, and the substrate and the shell define an accommodating space; the substrate is provided with a heat conduction surface and a heat dissipation surface which are oppositely arranged; the heat conduction face faces the interior of the containing space, the heat dissipation face faces the exterior of the containing space, and the multiple heat dissipation fins are all arranged on the heat dissipation face. The power device is accommodated in the accommodating space; the heat-insulating layer is arranged on the heat-conducting surface and is provided with a mounting groove; the insulating heat-conducting layer is accommodated in the mounting groove and is in contact with at least part of the surface of the power device and the heat-conducting surface. By means of the mode, the power converter can reduce heat conduction between the radiator and the interior of the containing space, so that the overall heat dissipation efficiency of the power converter is improved.

Description

Technical Field

[0001] This application relates to the field of power equipment technology, and in particular to a power converter. Background Technology

[0002] In current power converters, the heat generated by the power devices within the containment space is conducted to the heat sink via a semiconductor cooling device. The flowing air in the external environment then carries away the heat from the heat sink, thus cooling the power devices. However, in addition to transferring heat to the external environment, the heat sink can also transfer heat back into the containment space in the reverse direction. This results in a decrease in the temperature of the power devices while an increase in the temperature within the containment space, affecting the overall heat dissipation of the power converter. Summary of the Invention

[0003] The purpose of this application is to provide a power converter that reduces heat conduction between the heat sink and the interior of the housing space, thereby improving the overall heat dissipation efficiency of the power converter.

[0004] According to some aspects of this application, a power converter is provided, including a housing, a heat sink, a power device, a heat insulation layer, and a semiconductor cooling device; the heat sink includes a substrate and a plurality of heat dissipation fins; the substrate is mounted and fixed to the housing and encloses the housing to form a receiving space, the substrate having a heat-conducting surface and a heat-dissipating surface disposed opposite to each other; the heat-conducting surface faces inward of the receiving space, the heat-dissipating surface faces outward of the receiving space, and the plurality of heat dissipation fins are disposed on the heat-dissipating surface; the power device is housed in the receiving space; the heat insulation layer is disposed on the heat-conducting surface; the thermal conductivity of the heat insulation layer is less than or equal to 0.035 W / m·K, and is capable of absorbing and / or reflecting thermal radiation incident through the substrate; the heat insulation layer has a mounting groove; the insulating heat-conducting layer is housed in the mounting groove and is in contact with at least a portion of the surface of the power device and the heat-conducting surface respectively.

[0005] Optionally, the heat insulation layer includes a heat insulation material layer and a heat shielding film layer, with the heat insulation material layer facing the receiving space and the heat shielding film layer facing the substrate.

[0006] Optionally, the heat insulation layer is made of a heat insulation material, which contains one or more of titanium dioxide particles, zinc oxide particles, nano-aluminum particles, and reflective glass microspheres.

[0007] Optionally, the ratio of the projected area of ​​the heat insulation layer to the difference between the projected area of ​​the substrate and the projected area of ​​the mounting groove is between 90% and 100% on the plane where the substrate is located.

[0008] Optionally, the substrate is screwed to the housing around its perimeter by threaded fasteners, and sealant is filled in the gap between the substrate and the housing.

[0009] Optionally, a plurality of the heat dissipation fins are evenly distributed at equal intervals on the heat dissipation surface, and each heat dissipation fin is plate-shaped.

[0010] Optionally, the power converter includes a thermoelectric cooler; the thermoelectric cooler is housed in the mounting slot, the thermoelectric cooler has a cold side and a hot side disposed opposite to each other, the cold side is in contact with at least a portion of the surface of the power device through the insulating thermally conductive layer, and the hot side is in contact with the thermally conductive surface through the insulating thermally conductive layer.

[0011] Optionally, the power converter includes a cooling fan; the cooling fan is located outside the housing space, and the direction of airflow from the cooling fan is towards the direction in which the plurality of heat dissipation fins are arranged.

[0012] Optionally, the power converter further includes a controller, a temperature sensing element, a signal transmitter, and a signal receiver; The controller, temperature sensing element, and signal transmitter are all housed within the housing space. The temperature sensing element and signal transmitter are both electrically connected to the controller. The temperature sensing element is attached to the semiconductor refrigeration device. The signal receiver is located outside the housing, and is communicatively connected to the signal transmitter and electrically connected to the cooling fan.

[0013] Optionally, the signal receiver is used for communication connection with a terminal device.

[0014] Optionally, the power converter is an energy storage converter, and the power device is an IGBT.

[0015] The beneficial effects of the embodiments of this application are as follows: The power converter involved in this application reduces heat conduction between the heat sink and the interior of the housing space by setting a heat insulation layer with heat insulation, heat radiation absorption, and heat radiation reflection properties, thereby achieving a better cooling effect for the power device and improving the overall heat dissipation efficiency of the power converter. Compared with the heat dissipation method of adding heat exchangers and fans inside the power converter, the power converter involved in this application only adds a heat insulation layer, reducing the cost and size of the power converter. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0017] Figure 1 This is a schematic diagram of the structure of a power converter provided in one embodiment of this application; Figure 2 for Figure 1 This shows one of the cross-sectional views of the power converter; Figure 3 for Figure 1 The diagram shown illustrates the heat dissipation principle of the power converter; Figure 4a This is a block diagram of a power converter shown in comparison. Figure 4b A structural block diagram of a power converter shown in an embodiment; Explanation of reference numerals in the attached figures: 1. Outer shell; 2. Heat sink; 21. Base plate; 211. Thermally conductive surface; 212. Heat dissipation surface; 22. Heat dissipation fins; 1a. Containment space; 3. Power devices; 4. Insulation layer; 4a. Mounting groove; 5. Insulating and thermally conductive layer; 6. Cooling fan. Detailed Implementation

[0018] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this application or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0019] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0020] In the description of this application, it should be noted that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is usually based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this application and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this application; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0021] In the description of this application, it should be noted that the use of terms such as "first" and "second" to define the components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this application.

[0022] The technical features involved in the different embodiments of this application described below can be combined with each other as long as they do not conflict with each other.

[0023] Please see also Figures 1 to 3 According to one embodiment of this application, a power converter includes a housing 1, a heat sink 2, a power device 3, a heat insulation layer 4, and an insulating and thermally conductive layer 5.

[0024] The outer casing 1 serves not only as a protective structure for the power device 3, but also as a mounting base for the heat sink 2.

[0025] The heat sink 2 is installed and fixed to the outer casing 1 and forms a receiving space 1a with the outer casing 1. The power device 3 is received in the receiving space 1a and is opposite to the heat sink 2 and spaced apart.

[0026] A heat insulation layer 4 is located between the power device 3 and the heat sink 2 and is attached to at least a portion of the surface of the heat sink 2. The heat insulation layer 4 has a mounting groove 4a, and an insulating and thermally conductive layer 5 is housed within the mounting groove 4a. The thermal conductivity of the heat insulation layer 4 is less than or equal to 0.035 W / m·K, and it is capable of absorbing and / or reflecting the heat radiation incident on the heat sink 2.

[0027] An insulating and thermally conductive layer 5 is located between the power device 3 and the heat sink 2 and is in contact with at least a portion of the surfaces of the power device 3 and the heat sink 2, respectively. For example, the material of the insulating and thermally conductive layer 5 includes thermally conductive silicone grease, alumina, aluminum nitride, silicon nitride, or other suitable insulating materials with high thermal conductivity.

[0028] Therefore, the insulating thermally conductive layer has good thermal conductivity. The heat generated by the power device 3 when it is powered on can be conducted to the heat sink 2 through the insulating thermally conductive layer 5. The flowing air in the external environment can carry away the heat on the heat sink 2, thereby cooling the power device 3.

[0029] Understandably, the thickness and shape of the insulating and heat-conducting layer 5 can be adjusted adaptively according to the actual situation, provided that the power device 3 is operating normally. There are no restrictions here.

[0030] To facilitate the reader's understanding, the following example uses a power converter as an energy storage converter, where power device 3 is an IGBT (Insulated Gate Bipolar Transistor).

[0031] The drive control circuit of the energy storage converter is integrated into the control circuit board. The entire drive control circuit contains numerous power devices, which, in order of heat generation, are IGBTs, power inductors, relays, and capacitors. The heat generated by these electronic devices accounts for more than 90% of the total heat generated by the drive control circuit of the energy storage converter during continuous operation, with IGBTs contributing the largest share.

[0032] It should be noted that, since the space of energy storage converters is usually limited by size and the heat dissipation area is limited, increasing the heat dissipation area or improving thermal conductivity requires more physical space, which conflicts with the design requirements of compact and efficient equipment. Therefore, it is necessary to achieve effective heat dissipation within a limited space.

[0033] Of course, the power device 3 is not limited to an IGBT transistor; the power device 3 can be selected from different types depending on the type of power converter. For example, in some embodiments, the power converter is a motor driver, and the power device 3 can be a BJT (bipolar junction transistor) or a MOSFET.

[0034] For the housing 1 and the heat sink 2, in some embodiments, the material of the housing 1 can be selected according to the application scenario. For example, when the power converter is used in harsh conditions such as high temperature and high humidity, the housing 1 can be made of stainless steel or composite materials. The heat sink 2 can be made of metal materials with good thermal conductivity, such as aluminum alloy or copper, to meet the heat dissipation requirements of the power device 3.

[0035] In some embodiments, the housing 1 has an installation port that connects the external environment with the interior of the housing 1.

[0036] The heat sink 2 includes a base plate 21 and a plurality of heat dissipation fins 22. The base plate 21 is mounted and fixed to the housing 1 to close the mounting opening, thereby forming a receiving space 1a by the base plate 21 and the housing 1. The base plate 21 has a heat-conducting surface 211 and a heat-dissipating surface 212 arranged opposite to each other. The heat-conducting surface 211 faces inward to the receiving space 1a, and the heat-dissipating surface 212 faces outward to the receiving space 1a. The plurality of heat dissipation fins 22 are all disposed on the heat-dissipating surface 212.

[0037] For example, such as Figure 1As shown in Figure 3, the mounting port is roughly rectangular in shape. The outer contour of the substrate 21 matches the opening contour of the mounting port, and the size of the substrate 21 is slightly larger than the size of the mounting port. The periphery of the mounting port is defined by the threaded fasteners that can be screwed to the outer shell 1. After installation, it fits against the outer wall of the outer shell 1, and the gap between the substrate 21 and the outer shell 1 is filled with sealant. This provides sealing, moisture protection, and dust protection for the energy storage converter, meeting the protection level ≥ IP65.

[0038] For example, continue as follows Figure 1 As shown, several heat dissipation fins 22 are evenly distributed at equal intervals on the heat dissipation surface 212, and each heat dissipation fin 22 is plate-shaped. The advantage of this arrangement is that while increasing the number of heat dissipation fins 22, it does not occupy additional space, thus ensuring that the heat sink 2 can be used in power converters with limited installation space.

[0039] Of course, in order to achieve a more uniform heat conduction effect, in some embodiments, the heat dissipation fins 22 can be set in a "U" shape, with a predetermined distance between them, and fixed by the substrate 21. The "U" shaped heat dissipation fins 22 increase the contact area with the air compared with the plate-shaped heat dissipation fins 22, thus further improving the heat dissipation efficiency.

[0040] Alternatively, in other embodiments, the heat dissipation fins 22 can be configured as square waveforms, and several bending portions can be set on the integrated heat dissipation fins 22 by means of bending or other methods. The advantage of this configuration is that it can ensure uniform heat dissipation of the heat dissipation fins 22, while increasing the stability of the heat sink 2 and improving the service life of the power converter.

[0041] Please see Figure 3 In some embodiments, the power converter includes a semiconductor cooling device. The semiconductor cooling device has a cold side and a hot side disposed opposite to each other. The cold side faces inward into the housing space 1a and is in contact with at least a portion of the surface of the power device 3 through an insulating thermally conductive layer 5, while the hot side faces outward from the housing space 1a and is in contact with the thermally conductive surface 211 through the insulating thermally conductive layer 5.

[0042] For example, the semiconductor cooling device is a TEC (Thermoelectric Cooler) semiconductor cooling chip, which has positive and negative power lines that can be electrically connected to the power supply circuit on the power converter. Thus, when the TEC semiconductor cooling chip is working, the cold side contacts the power device 3 to absorb heat, and the hot side contacts the heat sink 2 to conduct heat. It should be noted that the aforementioned TEC semiconductor cooling chip utilizes the Peltier effect of semiconductor materials. When direct current passes through a thermocouple composed of two different semiconductor materials (generally N-type and P-type semiconductors) connected in series, heat is absorbed and released at the two ends of the thermocouple, respectively, to achieve cooling.

[0043] It is understood that the various embodiments of this application do not limit the correspondence between the semiconductor cooling device and the power device 3. That is, one power device 3 can be cooled by multiple semiconductor cooling devices together, or one semiconductor cooling device can cool multiple power devices 3 at the same time.

[0044] Because the temperature difference between the hot and cold sides of a TEC (thermal energy dispersive condenser) is constant, when the cold side absorbs heat and its temperature rises, the hot side also heats up. To maintain a lower temperature on the cold side, the temperature of the hot side can be reduced. By keeping the temperature difference constant, the cold side can provide a better cooling effect. For example... Figure 3 As shown, in some embodiments, the power converter includes a cooling fan 6. The cooling fan 6 is located outside the housing space 1a, and the airflow from the cooling fan 6 is directed towards the direction in which the heat dissipation fins 22 are arranged. When the cooling fan 6 starts to rotate, the generated airflow passes between adjacent heat dissipation fins 22, thereby increasing the airflow speed and accelerating the heat exchange rate between the heat dissipation fins 22 and the air, thereby reducing the temperature of the hot surface.

[0045] To adjust the output power of the thermoelectric cooler and cooling fan 6 according to the real-time changes in heat generated by the power device 3, in some embodiments, the power converter further includes a controller, a temperature sensing element, a signal transmitter, and a signal receiver. The controller and signal transmitter are integrated into a control circuit board, the temperature sensing element is attached to the thermoelectric cooler, and both the temperature sensing element and the signal transmitter are electrically connected to the controller. The signal receiver is located outside the housing 1, and is communicatively connected to the signal transmitter and electrically connected to the cooling fan 6.

[0046] By monitoring the thermoelectric cooling device, the power consumption of the thermoelectric cooling device can be automatically adjusted. For example, when the temperature sensing element detects that the temperature of the thermoelectric cooling device is too low, it means that the cooling of the power device 3 has been completed. Therefore, the current to the thermoelectric cooling device and the output power of the cooling fan 6 can be reduced or stopped. When the temperature sensing element detects that the temperature of the hot surface of the thermoelectric cooling device is too high, it means that the cooling of the power device 3 has not been completed. At this time, the current of the thermoelectric cooling device can be increased or an alarm can be provided to the user.

[0047] To achieve the aforementioned alarm effect, a signal receiver is further used for communication connection with the terminal device. The signal transmitter and receiver enable signal connection between the controller and the terminal device, providing real-time feedback on the operating status of the thermoelectric cooler. Additionally, the controller can be remotely operated via the terminal device, such as turning it on, off, and adjusting the current of the thermoelectric cooler.

[0048] Of course, the cooling fan 6 can also be replaced by a liquid cooler 2, with multiple cooling pipes of the liquid cooler 2 corresponding to and contacting multiple heat dissipation fins 22.

[0049] In some embodiments, the heat insulation layer 4 includes a heat insulation material layer and a heat shielding film layer stacked together. Both the heat insulation material layer and the heat shielding film layer are layered structures, with the heat insulation material layer facing inward into the receiving space 1a and the heat shielding film layer facing the substrate 21.

[0050] For example, the heat insulation layer can be made of insulating materials, such as heat insulation felt, plexiglass, aerogel, etc. The heat shielding film layer is bonded to the heat insulation material using a vacuum lamination process. The heat shielding film layer can be made of white PET film (polyethylene terephthalate film) or metal film. The metal film can be aluminum foil or a film plated with metals such as nickel, silver, or copper. Alternatively, it can be a multilayer metal film containing metals such as silver, titanium, or aluminum, or metal oxides such as Ti2O3 or Al2O3, formed using magnetron sputtering technology. The multilayer reflective structure improves the reflectivity of infrared rays, ensuring both heat radiation reflection characteristics and thinness.

[0051] Furthermore, both surfaces of the heat-shielding film are designed with a mirror structure to reduce the scattering and absorption of light during reflection, thereby improving reflectivity.

[0052] And / or, the heat insulation layer 4 is made of heat insulation material, to which one or more of titanium dioxide particles, zinc oxide particles, nano-aluminum particles, or reflective glass microspheres are added. The diameter of the reflective glass microspheres is between 50 micrometers and 150 micrometers.

[0053] Alternatively, in some embodiments, the heat insulation layer 4 is simply a layered structure formed on the heat-conducting surface 211. For example, the heat insulation layer 4 can be formed after spraying a heat-insulating coating containing nano-tungsten oxide onto the heat-conducting surface 211, in which case the radiator 2 also has a heat insulation function.

[0054] Continue as Figure 2 As shown, in some embodiments, the ratio of the projected area of ​​the heat insulation layer 4 to the projected area of ​​the substrate 21 minus the projected area of ​​the mounting groove 4a is between 90% and 100% when projected onto the plane of the substrate 21. This increases the heat radiation reflection area of ​​the heat insulation layer 4, enabling it to fully reflect the heat radiation entering from the substrate 21. Furthermore, the heat transferred in the reverse direction by the heat sink 2 diffuses to all areas of the heat insulation layer 4, reducing the risk of localized overheating.

[0055] In summary, the power converter of this application reduces heat conduction between the heat sink 2 and the interior of the housing space 1a by incorporating a heat insulation layer 4 with heat insulation, heat radiation absorption, and heat radiation reflection properties, thereby achieving a better cooling effect for the power device 3 and improving the overall heat dissipation efficiency of the power converter. Compared to heat dissipation methods that add heat exchangers and fans inside the power converter, the power converter of this application only adds a heat insulation layer 4, reducing the cost and size of the power converter.

[0056] The present application will be further illustrated below with reference to embodiments and comparative examples. Various tests and evaluations were performed according to the methods described below. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the application.

[0057] like Figure 4a and Figure 4b As shown, the power converters in the comparative example and the embodiment have the same specifications and parameters, and both include a housing 1, a heat sink 2, a power device 3, an insulating thermally conductive layer 5, and a cooling fan 6. The insulating thermally conductive layer 5 is made of thermally conductive silicone grease.

[0058] The difference between the comparative example and the embodiment lies only in that the power converter in the embodiment further includes a heat insulation layer 4, which comprises a heat insulation felt and an aluminum foil stacked together. The heat insulation felt faces inward into the receiving space 1a, and the aluminum foil faces the substrate 21. The ratio of the projected area of ​​the heat insulation layer 4 to the projected area of ​​the substrate 21 minus the projected area of ​​the mounting groove 4a, when projected onto the plane of the substrate 21, is 90%. The heat insulation felt has a thickness of 5 mm and a thermal conductivity of 0.02 W / m·K. The aluminum foil has a thickness of 0.006 mm to 0.2 mm and a thermal reflectivity of 70%.

[0059] The test conditions for the comparative examples and embodiments are shown in Table 1 below.

[0060] The ambient temperature within the containment space of the power converter and the temperature at 5 points on the insulating thermal conductive layer were measured in both the experimental and control groups. The samples were run for 2 hours until they stabilized. The measured data are shown in Table 2 below.

[0061] Compared to the comparative example, after adding the heat insulation layer 4 in the embodiment, the temperature of the insulating and heat-conducting layer 5 and the internal temperature of the power converter's containment space 1a both decreased. Specifically, the semiconductor temperature decreased by 6.3°C and the internal cavity ambient temperature decreased by 5°C, demonstrating that the heat insulation layer 4 can reduce heat convection and heat conduction between the heat sink 2 and the power device 3.

[0062] The above description is merely an embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A power converter, characterized by, The power converter comprises: a housing; a heat sink comprising a substrate and a plurality of heat dissipation fins; the substrate is fixedly mounted on the housing and forms a containing space with the housing; the substrate has a heat-conducting surface and a heat-dissipating surface arranged oppositely; the heat-conducting surface faces the containing space, and the heat-dissipating surface faces the outside of the containing space; the plurality of heat dissipation fins are arranged on the heat-dissipating surface; a power device contained in the containing space; a thermal insulation layer arranged on the heat-conducting surface; the thermal insulation layer has a thermal conductivity less than or equal to 0.035 W / m·k and can absorb and / or reflect thermal radiation incident through the substrate; the thermal insulation layer is provided with a mounting groove; an insulating and heat-conducting layer contained in the mounting groove and in contact with at least part of the surface of the power device and the heat-conducting surface, respectively.

2. The power converter of claim 1, wherein, The thermal insulation layer comprises a thermal insulation material layer and a heat shielding film layer arranged in a stack; the thermal insulation material layer faces the containing space, and the heat shielding film layer faces the substrate. Alternatively, the thermal insulation layer is made of a thermal insulation material mixed with one or more of titanium dioxide particles, zinc oxide particles, nano-aluminum particles, and light-reflecting glass microbeads.

3. The power converter of claim 1, wherein, The ratio of the projected area of the thermal insulation layer to the difference between the projected area of the substrate and the projected area of the mounting groove is between 90% and 100% when projected on the plane of the substrate.

4. The power converter of claim 1, wherein, The periphery of the substrate is fixed to the housing by screwing with threaded fasteners, and the gap between the substrate and the housing is filled with sealant.

5. The power converter of claim 1, wherein, The plurality of heat dissipation fins are arranged equidistantly and uniformly on the heat-dissipating surface, and each heat dissipation fin is arranged in a plate shape.

6. The power converter of any one of claims 1-5, wherein, The power converter comprises a semiconductor refrigerator; the semiconductor refrigerator is contained in the mounting groove; the semiconductor refrigerator has a cold surface and a hot surface arranged oppositely; the cold surface is in contact with at least part of the surface of the power device through the insulating and heat-conducting layer, and the hot surface is in contact with the heat-conducting surface through the insulating and heat-conducting layer.

7. The power converter of claim 6, wherein, The power converter comprises a heat dissipation fan; the heat dissipation fan is arranged outside the containing space; the direction of the air outlet of the heat dissipation fan is toward the direction in which the plurality of heat dissipation fins are arranged.

8. The power converter of claim 7, wherein, The power converter further comprises a controller, a temperature sensing element, a signal transmitter, and a signal receiver. The controller, the temperature sensing element, and the signal transmitter are contained in the containing space; the temperature sensing element and the signal transmitter are electrically connected to the controller; the temperature sensing element is attached to the semiconductor refrigerator; The signal receiver is located outside the housing; the signal receiver is communicatively connected to the signal transmitter and electrically connected to the heat dissipation fan.

9. The power converter of claim 8, wherein, The signal receiver is used for communication connection with a terminal device.

10. The power converter of any one of claims 1-6, wherein, The power converter is an energy storage converter, and the power device is an IGBT tube.

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