A heat dissipation structure for a reactor of a heat pump frequency converter

Abstract

The utility model discloses a kind of heat-dissipating structure of reactor heat dissipation of heat pump frequency converter, including magnetic core body, winding and heat conductor. The winding is flat copper band type structure, along the annular periphery of magnetic core body multilayer winding, for reducing skin effect and proximity effect loss under high-frequency carrier condition, to reduce winding heat generation and improve energy transmission efficiency. The heat conductor is fixedly installed on the inner side of magnetic core body, including the heat-dissipating block of the guide plate and both sides fixedly connected along the inner arc surface of magnetic core body, wind hole is equipped on guide plate, and the surface of heat-dissipating block is equipped with multiple parallel heat-dissipating strips. The structure forms efficient heat-conducting channel between heat conductor and magnetic core body, and heat is rapidly discharged using air convection, and the reactor temperature rise is significantly reduced. The structure can effectively improve the heat dissipation performance and operating stability of high-frequency PFC inductor, and is suitable for high-power density heat pump frequency converter system.

Description

Technical Field

[0001] This utility model relates to the field of heat pump frequency converter technology, specifically a heat dissipation structure for the reactor heat dissipation of a heat pump frequency converter. Background Technology

[0002] Heat pump frequency converters are widely used in energy-saving control systems, and their PFC circuits are used to improve the input power factor, reduce harmonic interference, and increase energy efficiency. The PFC inductor, as a key component of this circuit, needs to simultaneously meet the requirements of high inductance, low loss, and good heat dissipation performance under high-frequency carrier conditions. However, existing reactor structures generally have the following shortcomings when operating at high frequencies:

[0003] First, traditional reactors generally use a round copper wire winding structure. While round wire windings can meet basic inductance requirements in power frequency or low-frequency applications, under high-frequency carrier conditions (generally exceeding 30kHz) in PFC circuits, the uneven current distribution within the round wire easily leads to significant "skin effect" and "proximity effect," resulting in a reduction in the effective conductor cross-sectional area and an increase in AC impedance, thereby increasing winding losses and heat generation. This structure is prone to insulation aging, excessive core temperature rise, and even inductance performance degradation under long-term operation.

[0004] Secondly, the heat dissipation structures of existing reactors are generally inefficient. Traditional designs often use natural convection or add heat sinks to the outside of the magnetic core, but because heat inside the magnetic core is not easily dissipated, severe heat accumulation occurs, creating a temperature gradient. Especially in enclosed inverter structures, airflow is restricted, and the heat generated between the magnetic core and windings is difficult to effectively transfer to the external environment, resulting in an obstructed overall heat dissipation path, excessive temperature rise, and thus affecting the stability and lifespan of the inductor.

[0005] In summary, existing reactors used in heat pump frequency converters still suffer from problems such as high heat generation, low heat dissipation efficiency, and excessive temperature rise under high-frequency operating conditions, making it difficult to meet the stable operation requirements of high-power PFC circuits. Therefore, there is an urgent need for a new reactor heat dissipation structure that combines a high-frequency, low-loss winding structure with an efficient heat conduction and heat dissipation path to reduce inductor temperature rise, improve thermal balance, and enhance system operational reliability. Utility Model Content

[0006] This invention aims to solve the technical problems of existing reactors used in heat pump frequency converters under high-frequency PFC conditions, such as large winding losses, severe core heating, and insufficient heat dissipation. It provides a reactor heat dissipation structure that is compact, has high heat dissipation efficiency, and is suitable for high carrier frequency operation.

[0007] This utility model provides a reactor heat dissipation structure for a heat pump frequency converter, comprising a magnetic core, windings, and a heat conductor, wherein:

[0008] The winding is wound around the outer surface of the magnetic core, and the heat conductor is fixedly installed on the inner side of the magnetic core to dissipate the heat generated by the magnetic core and the winding during operation.

[0009] The winding is a flat copper strip structure, which is wound in multiple layers along the annular outer periphery of the magnetic core, and the heat conductor is closely attached to the magnetic core.

[0010] The heat conductor includes a guide plate that is attached to the inner arc surface of the magnetic core and heat sinks that are fixedly connected to both sides of the guide plate. The guide plate and heat sinks work together to form an efficient heat conduction and convection heat dissipation path, thereby reducing the overall temperature rise of the reactor.

[0011] This invention utilizes a combination of flat wire windings and a high thermal conductivity heat sink to enable PFC reactors to maintain low-loss characteristics under high carrier frequency operation. The flat wire winding structure effectively reduces skin effect and proximity effect losses under high-frequency current, while the heat sink can dissipate heat from the magnetic core and windings in real time, achieving dual optimization of electromagnetic and thermal balance. This structure is suitable for high-frequency PFC circuits in high-power-density heat pump inverters, significantly reducing operating temperature rise and extending device lifespan.

[0012] In a preferred example, the winding is made of enameled flat copper wire with a rectangular cross-section, with adjacent layers separated by an insulating varnish film, and is wound evenly in multiple layers along the annular outer periphery of the magnetic core.

[0013] Compared to traditional round wires, this flat wire structure has a larger conductor surface area and better heat dissipation performance. At the same time, due to the more uniform current distribution, it can significantly reduce AC losses caused by the skin effect and proximity effect, thereby maintaining low-loss operation under high-frequency carrier operation and improving the energy transmission efficiency of the PFC reactor.

[0014] Specifically, flat wire windings can withstand higher current densities without overheating within the same volume, allowing the overall reactor volume to be reduced by about 15% to 20%, which is beneficial for the compact structure and increased power density of heat pump frequency converters.

[0015] In a preferred embodiment, the heat conductor is fixedly mounted on the inner arc surface of the magnetic core and forms surface contact with the magnetic core to achieve efficient thermal coupling.

[0016] The heat conductor consists of a guide plate and a heat sink. The guide plate is tightly fitted along the inner arc surface of the magnetic core to directly absorb the heat generated during the operation of the magnetic core and conduct heat transfer. The heat sink is fixedly connected to the guide plate to expand the heat conduction area and realize heat diffusion.

[0017] Specifically, this dual-layer heat conduction structure of "internal heat conduction + external heat dissipation" enables the rapid dissipation of heat from inside the magnetic core within a short path, and effectively reduces the core's center temperature through convection heat exchange with the external air via the heat sink. In actual measurements, this structure can reduce the reactor's steady-state temperature rise by approximately 15°C or more.

[0018] In a preferred example, the guide plate has several radially penetrating air holes to form an air convection channel during equipment operation, allowing cold air to flow through the surface of the guide plate for convective heat exchange.

[0019] Specifically, the air vents can work with the system's air-cooled airflow to form local micro-airflow zones, accelerating the airflow speed on the guide plate and heat sink surface, improving heat dissipation efficiency, and thus achieving dual heat dissipation functions of natural convection and forced air cooling.

[0020] In a preferred embodiment, the surface of the heat sink is provided with a plurality of parallel heat dissipation strips, and heat dissipation gaps are formed between adjacent heat dissipation strips.

[0021] Specifically, heat dissipation slats increase the air contact area and promote airflow to create a vortex heat transfer effect, significantly improving the heat dissipation capacity of the heat conductor. Compared with the traditional flat plate structure, this structure can improve heat dissipation efficiency by about 30% at the same airflow velocity.

[0022] In a preferred example, the heat sink has internal grooves for accommodating and connecting the end wires of the windings through the heat conductor.

[0023] This structure not only ensures a reasonable layout of electrical wiring, but also avoids mechanical interference between the heat conductor and the winding, improving assembly accuracy and structural stability.

[0024] In a preferred example, the heat conductor is made of a high thermal conductivity aluminum-based or copper-based composite material with a thermal conductivity of not less than 200 W / m·K.

[0025] Specifically, the material has excellent thermal conductivity and low thermal resistance, which can quickly dissipate heat under high power operation and keep the temperature difference between the guide plate and the magnetic core within 5°C, ensuring stable and reliable heat transfer efficiency.

[0026] The beneficial effects achieved by this utility model are as follows:

[0027] 1. In this invention, by employing a flat copper strip winding wound around the outer surface of the magnetic core, the winding exhibits lower skin effect and proximity effect losses under high-frequency carrier conditions. Compared to the traditional round wire structure, the flat wire winding effectively reduces high-frequency AC impedance, improves the power transmission efficiency of the reactor under high-carrier-frequency PFC conditions, thereby significantly reducing heat generation and temperature rise, and improving the overall operational stability.

[0028] 2. In this invention, a heat conductor is disposed inside the magnetic core, and a high-efficiency heat conduction path is formed by the cooperation of a guide plate and a heat sink. The guide plate is disposed close to the inner arc surface of the magnetic core to directly absorb the heat generated during the operation of the magnetic core; multiple heat dissipation strips are arranged on both sides of the heat sink, and air holes are opened on the guide plate to form a natural or forced airflow channel, so that heat can be quickly discharged through air convection, thereby achieving efficient heat dissipation and thermal balance control of the reactor. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the overall structure of one embodiment of the present utility model;

[0030] Figure 2 This is an exploded structural diagram of one embodiment of the present invention;

[0031] Figure 3 This is a schematic diagram of the heat conductor structure according to an embodiment of the present invention.

[0032] Figure label:

[0033] 100. Magnetic core; 110. Winding;

[0034] 200, heat conductor; 210, guide plate; 220, heat sink; 211, air vent; 221, wire groove; 222, heat sink strip. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features of the present utility model can be combined with each other.

[0036] It should be understood that these descriptions are merely exemplary and not intended to limit the scope of this invention.

[0037] The following describes, with reference to the accompanying drawings, a heat dissipation structure for the reactor of a heat pump frequency converter, according to some embodiments of the present invention.

[0038] Combination Figures 1-3 As shown, the present invention provides a heat dissipation structure for the reactor of a heat pump frequency converter, including a magnetic core 100, a winding 110, and a heat conductor 200.

[0039] The magnetic core 100 is a toroidal ferrite structure used to form a closed magnetic flux path, and its surface, after insulation treatment, serves as the supporting base for the winding 110. The winding 110 is wound around the outer peripheral surface of the magnetic core 100 and is composed of a flat copper strip conductor, with multiple layers wound along the toroidal direction of the magnetic core 100. The flat copper strip structure has a larger contact area and lower AC resistance, which can effectively reduce the skin effect and proximity effect, reduce high-frequency loss, and thus improve the power conversion efficiency of the PFC reactor under high carrier frequency conditions.

[0040] The heat conductor 200 is fixedly installed on the inner side of the magnetic core 100 to quickly dissipate the heat generated by the magnetic core 100 and winding 110 during high-frequency operation. The heat conductor 200 and the magnetic core 100 adopt a surface contact and tight fit structure to ensure efficient heat conduction.

[0041] In this embodiment, the heat conductor 200 includes a guide plate 210 and a heat sink 220. The guide plate 210 is fitted along the inner arc surface of the magnetic core 100, and its curvature is consistent with the inner wall of the magnetic core 100 to achieve sufficient thermal contact. Heat sinks 220 are fixedly connected to both sides of the guide plate 210. The heat sinks 220 adopt a metal heat diffusion structure to increase the heat exchange area and accelerate heat conduction to the air, thereby improving the overall heat dissipation efficiency of the reactor.

[0042] In this embodiment, a plurality of radially penetrating air holes 211 are uniformly formed on the guide plate 210. These air holes 211 penetrate the thickness direction of the guide plate 210 and form air convection channels during equipment operation. When the internal air-cooling system of the frequency converter or external airflow passes through, air can pass through the air holes 211 to exchange heat with the surface of the guide plate 210, creating a micro-airflow circulation inside the heat conductor 200, thereby effectively reducing the surface temperature of the heat conductor and the magnetic core. This structure not only improves the heat dissipation rate but also reduces localized temperature rise caused by heat accumulation.

[0043] In another embodiment, the surface of the heat sink 220 is provided with a plurality of parallel heat dissipation strips 222, each heat dissipation strip 222 being arranged parallel to each other and with uniform spacing, and ventilation gaps being formed between adjacent heat dissipation strips 222. The heat dissipation strips 222 can form multi-dimensional heat dissipation channels under natural convection or forced air cooling conditions, thereby significantly increasing the air contact area and improving heat dissipation efficiency.

[0044] The heat sink 220 also has a wire groove 221 inside, which is opened along the thickness direction of the heat sink 220 to accommodate and allow the lead-out end of the winding 110 to pass through the heat conductor 200 for electrical connection. The wire groove 221 not only ensures a smooth lead-out path for the winding 110, but also avoids mechanical interference between the heat conductor 200 and the winding 110, improving the compactness of the structural assembly and electrical safety.

[0045] In this embodiment, winding 110 is made of enameled flat copper wire with a rectangular cross-section, and adjacent layers are isolated by a highly insulating enamel film. The rectangular cross-section structure effectively reduces the circulating current effect on the conductor surface, reduces energy loss under high-frequency current, and improves thermal conductivity through a large-area lateral heat dissipation surface. Compared with the traditional round wire winding structure, the flat wire winding in this solution has lower losses and better heat distribution characteristics in the same volume, which can meet the low temperature rise requirements in high-frequency PFC inductor applications.

[0046] The heat conductor 200 is preferably made of a high thermal conductivity aluminum-based or copper-based composite material with a thermal conductivity of not less than 200 W / m·K. This high thermal conductivity material can quickly conduct the heat generated by the magnetic core 100 and winding 110 under the high-frequency operation of the heat pump inverter, and evenly dissipate it to the outside air through the heat sink 220 and heat dissipation strip 222, forming an efficient heat conduction path.

[0047] In practical applications, the heat conductor 200 can contact the magnetic core 100 through thermal grease, thermal adhesive, or phase change thermal pads to minimize interfacial thermal resistance. This composite structure ensures that heat is rapidly conducted to the heat sink 220 under continuous operation of the PFC reactor, preventing performance degradation and device aging caused by heat buildup.

[0048] Working principle:

[0049] When this invention is used in the PFC circuit of a heat pump inverter, the flat winding 110 achieves low-loss characteristics under high carrier frequency operation by increasing the conductor surface area and reducing AC resistance, thereby reducing the overall heat generation of the reactor. The heat generated by the magnetic core 100 under high-frequency magnetic flux changes is conducted to the heat sink 220 through the tightly fitted guide plate 210, and then rapidly dissipated through the airflow of the heat sink 222 and the vents 211.

[0050] Through the synergistic design of the flat winding 110 structure and the high-efficiency heat conductor 200, this utility model significantly improves the heat dissipation efficiency of the reactor, enabling it to maintain a stable temperature under high-frequency and high-carrier operation conditions, avoiding the impact of heat accumulation on surrounding components, thereby extending the overall service life of the heat pump inverter.

[0051] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present 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.

[0052] Although embodiments of the present 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 present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A heat dissipation structure for the reactor of a heat pump frequency converter, characterized in that, The device includes a magnetic core (100), a winding (110) wound around the surface of the magnetic core (100), and a heat conductor (200) fixedly installed inside the magnetic core (100). The winding (110) is a flat copper strip structure and is wound in multiple layers along the annular outer periphery of the magnetic core (100). The heat conductor (200) is closely attached to the magnetic core (100) and is used to quickly dissipate the heat generated by the magnetic core (100) when it is operating at high frequency. The heat conductor (200) includes a guide plate (210) and a heat sink (220). The guide plate (210) is attached to the inner arc surface of the magnetic core (100), and the heat sink (220) is fixedly connected to both sides of the guide plate (210) to enhance the heat conduction area.

2. The heat dissipation structure for reactor heat dissipation in a heat pump frequency converter according to claim 1, characterized in that, The guide plate (210) has radially penetrating air holes (211) to form an air convection channel during equipment operation, allowing air to flow through the surface of the guide plate (210) to accelerate heat dissipation.

3. The heat dissipation structure for reactor heat dissipation in a heat pump frequency converter according to claim 1, characterized in that, The surface of the heat sink (220) is provided with a plurality of parallel heat sink strips (222), and heat sink gaps are formed between adjacent heat sink strips (222) to expand the convective heat dissipation area.

4. The heat dissipation structure for reactor heat dissipation in a heat pump frequency converter according to claim 1, characterized in that, The heat sink (220) has a wire groove (221) for accommodating and allowing the winding (110) to pass through.

5. The heat dissipation structure for reactor heat dissipation in a heat pump frequency converter according to claim 1, characterized in that, The winding (110) is made of enameled flat copper wire with a rectangular cross section, and adjacent layers are separated by an insulating varnish film to reduce AC losses caused by skin effect and proximity effect.

6. The heat dissipation structure for reactor heat dissipation in a heat pump frequency converter according to claim 1, characterized in that, The heat conductor (200) is made of high thermal conductivity aluminum-based or copper-based composite material with a thermal conductivity of not less than 200 W / m·K, and is used to quickly remove heat in high frequency PFC operation.

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