An insulation fixing and over-temperature protection device for high-frequency resonant transformer

Abstract

This invention relates to the fields of power electronic equipment, high-frequency magnetic components, and safety protection technology, and particularly to an insulation fixing and over-temperature protection device for a high-frequency resonant transformer. The technical solution includes a toroidal magnetic core, a primary winding, a secondary winding, and a high-frequency resonant inverter module, as well as an insulation clamping assembly, a winding isolation component, a temperature detection element, an elastic clamping component, a temperature protection assembly, and an input power-off assembly. The insulation clamping assembly includes a first clamping component and a second clamping component connected to each other, forming a positioning space for accommodating and fixing the toroidal magnetic core. This invention solves the problems of unstable toroidal magnetic core positioning, unclear division of primary and secondary windings, unstable contact of the temperature detection element, and inability to reliably cut off the input power supply when over-temperature occurs or the detection element is open-circuited, through the coordination of mechanical positioning, isolation, elastic contact, and circuit control.

Description

Technical Field

[0001] This invention relates to the fields of power electronic equipment, high-frequency magnetic components and safety protection technology, and in particular to an insulation fixing and over-temperature protection device for a high-frequency resonant transformer. Background Technology

[0002] High-frequency resonant transformers typically utilize high-frequency resonant inverter modules to generate alternating excitation in the primary winding and transfer electrical energy to the secondary winding through a toroidal magnetic core. They can be used for isolated AC power supply, levitation drive power supply, and other high-frequency energy transmission scenarios.

[0003] Experimental toroidal transformers often employ a method of manually winding the primary and secondary windings after wrapping the magnetic core with insulating tape. The magnetic core and windings are typically fixed by binding or gluing. This method lacks a unified axial, radial, and circumferential positioning reference, making the magnetic core prone to movement. The primary and secondary windings may also slide along the circumference of the magnetic core, approach each other, or overlap, making it difficult to maintain stable assembly consistency and insulation spacing.

[0004] The center-tapped primary winding consists of two half-windings that work alternately. When the number of turns, position, or connection of the two half-windings is inconsistent, or when the input voltage, resonant parameters, and core characteristics are mismatched, core losses and excitation current may increase, and abnormal temperature rise may easily occur after continuous operation.

[0005] Existing temperature sensing elements are typically fixed near the magnetic core using adhesive bonding or suspended in the winding gap. Aging of the adhesive layer, assembly gaps, and winding displacement can all alter the temperature sensing contact state, making the temperature detection results inconsistent in reflecting the magnetic core surface temperature. Simultaneously, switching interference generated by the high-frequency resonant inverter module can cause simple threshold detection circuits to malfunction near the critical temperature.

[0006] Furthermore, some over-temperature protection structures can only detect a single high-temperature state and cannot identify open-circuit faults in the temperature sensing element and its leads. Moreover, the relay may repeatedly engage and disengage near the temperature threshold. Therefore, this application proposes an insulation fixing and over-temperature protection device for high-frequency resonant transformers. Summary of the Invention

[0007] The purpose of this invention is to address the problems of unstable positioning of toroidal magnetic cores and windings, unclear division of primary and secondary windings, unstable contact of temperature sensing elements, and inability to reliably cut off the input power supply when the magnetic core is overheated or the temperature sensing element is open-circuited. This invention proposes an insulation fixing and over-temperature protection device for high-frequency resonant transformers.

[0008] The technical solution of the present invention: An insulation fixing and over-temperature protection device for a high-frequency resonant transformer, comprising a toroidal magnetic core, a primary winding, a secondary winding and a high-frequency resonant inverter module, and further comprising an insulation clamping assembly, a winding isolation component, a temperature detection element, an elastic clamping component, a temperature protection assembly and an input power-off assembly;

[0009] The insulating clamping assembly includes a first clamping member and a second clamping member connected to each other, forming a positioning space between them for accommodating and fixing the annular magnetic core;

[0010] The winding isolation element is disposed on the annular magnetic core and is used to isolate the primary winding and the secondary winding along the circumference of the annular magnetic core.

[0011] The temperature sensing element is disposed between the insulating clamping assembly and the annular magnetic core, and the elastic clamping member continuously presses the temperature sensing element against the surface of the annular magnetic core.

[0012] The temperature protection component is electrically connected to the temperature detection element, and the control output terminal of the temperature protection component is connected to the control terminal of the input power-off component; the main path of the input power-off component is connected in series between the DC power supply and the high-frequency resonant inverter module, and the temperature protection component is at least used to control the input power-off component to cut off the power supply to the high-frequency resonant inverter module when there is an over-temperature or detection element failure.

[0013] Optionally, the first clamping member and the second clamping member are respectively provided with annular positioning grooves that are adapted to the shape of the annular magnetic core on their opposing sides. In the assembled state, the two annular positioning grooves together constitute the positioning space to restrict the axial and radial movement of the annular magnetic core.

[0014] Optionally, the insulating clamping assembly is provided with an isolator mounting groove, the winding isolator is a U-shaped partition, the end of the U-shaped partition is directly embedded in the isolator mounting groove, and the groove wall of the isolator mounting groove restricts its movement along the circumference of the annular magnetic core or its tilt relative to the insulating clamping assembly.

[0015] The mounting groove for the isolator is a strip-shaped groove extending radially along the annular magnetic core. The width of the strip-shaped groove is greater than the thickness of the U-shaped partition to allow for assembly clearance.

[0016] Optionally, the primary winding is a center-tapped primary winding, including a first primary half-winding and a second primary half-winding with the same number of turns; one end of the first primary half-winding and the second primary half-winding together form a center tap, and the other end is respectively connected to the two alternating output terminals of the high-frequency resonant inverter module.

[0017] Optionally, the first or second clamping member is provided with a temperature sensing element mounting slot and a sensor lead slot communicating with the temperature sensing element mounting slot; the temperature sensing element is installed in the temperature sensing element mounting slot, and its lead is independently led out along the sensor lead slot to avoid the primary winding area.

[0018] Optionally, the temperature sensing element is an NTC thermistor, and the elastic clamping component is a heat-resistant elastic silicone block or a heat-resistant elastic foam.

[0019] Optionally, the temperature protection component includes a sampling voltage divider unit, an RC filter unit, a threshold comparison unit, a fault latch unit, and a relay drive unit; the sampling voltage divider unit is connected to the threshold comparison unit via the RC filter unit, the fault output terminal of the threshold comparison unit is connected to the fault set terminal of the fault latch unit, and the operation enable output terminal of the fault latch unit is connected to the relay drive unit.

[0020] The threshold comparison unit includes a high temperature comparison unit and a sensor open circuit comparison unit, which are respectively used to output a first fault signal or a second fault signal when the temperature sampling voltage reaches the high temperature threshold or the threshold corresponding to the open circuit of the detection element.

[0021] The first fault signal and the second fault signal are connected to the fault setting terminal of the fault latch unit via a signal merging branch; the fault latch unit is connected to a reset switch and maintains a power-off control state after receiving any fault signal until the fault condition is cleared and a reset signal is received.

[0022] Optionally, the input power-off component includes a relay coil and a normally open main contact of the relay connected in series between the DC power supply and the high-frequency resonant inverter module; the relay drive unit controls the energization and de-energization of the relay coil according to the operation permission output terminal; under normal conditions, the relay coil is energized to close the normally open main contact, and under fault conditions or when the temperature protection component is de-energized, the relay coil is de-energized to open the normally open main contact.

[0023] The temperature protection component further includes a status indication unit, which includes at least one of a normal status indication, an over-temperature status indication, and a sensor open-circuit fault status indication.

[0024] Optionally, the temperature protection component is powered by a control power supply, the input terminal of which is connected to the power input side of the normally open main contact of the relay, so as to keep the temperature protection component continuously powered after the normally open main contact of the relay is opened.

[0025] Optionally, the outer surface of the annular magnetic core is provided with an insulating encapsulation layer, which is at least one of PBT encapsulation layer, polyimide insulating layer, polyester insulating layer, and glass fiber insulating layer.

[0026] Compared with the prior art, this application includes at least one of the following beneficial technical effects:

[0027] The annular positioning grooves on the first and second insulating clamps cooperate to restrict the axial and radial displacement of the annular magnetic core; the end of the U-shaped isolation plate is embedded in the isolation plate mounting groove, and the groove wall restricts its movement and tilting along the circumference of the annular magnetic core, defining the boundary between the primary winding area and the secondary winding area along the circumference of the annular magnetic core, so that the windings are spatially separated.

[0028] The elastic clamping component generates elastic deformation, continuously pressing the temperature sensing element against the surface of the toroidal magnetic core, avoiding temperature measurement position displacement caused by adhesive aging or assembly gaps; the lead wire of the temperature sensing element is led out through an independent sensor lead wire slot, which is separated from the primary winding area, reducing the crossing of the temperature sensing lead wire with the high-frequency primary winding.

[0029] The RC filter unit filters the temperature sampling signal to attenuate high-frequency switching interference; the high-temperature comparison unit and the sensor open-circuit comparison unit respectively identify the over-temperature state of the magnetic core and the open-circuit state of the temperature detection element; the fault latching unit maintains the power-off control state after receiving any fault signal to prevent the relay from repeatedly operating near the temperature threshold; the input power-off component is connected in series between the DC power supply and the high-frequency resonant inverter module to cut off the power supply when there is over-temperature, sensor open circuit, or loss of power of the temperature protection component.

[0030] This invention solves the problems of unstable positioning of the toroidal magnetic core, unclear division of the primary and secondary windings, unstable bonding of the temperature detection element, and inability to reliably cut off the input power supply when the temperature is too high or the detection element is open-circuited by the combination of mechanical positioning, isolation, elastic bonding and circuit control. Attached Figure Description

[0031] Figure 1 This is a functional block diagram of the overall system of the DC power supply, input power-off component, high-frequency resonant inverter module, high-frequency resonant transformer and temperature protection component of the present invention.

[0032] Figure 2 This is a schematic diagram of the circuit principle of the temperature protection component of the present invention;

[0033] Figure 3 This is a schematic diagram of the mechanical structure of the present invention;

[0034] Figure 4 This is a schematic diagram of the overall assembly of the mechanical structure of the present invention;

[0035] Figure 5This is a top view of the structure of the first insulating clamping member of the present invention.

[0036] Reference numerals: 1. Sampling voltage divider unit; 2. RC filter unit; 3. High temperature comparison unit; 4. Sensor open circuit comparison unit; 5. Fault latching unit; 6. Relay drive unit; 7. First insulating clamping component; 8. Elastic clamping component; 9. Temperature detection element; 10. U-shaped isolation plate; 11. Non-metallic isolation post; 12. Second insulating clamping component; 13. Non-metallic fastener; 14. Ring magnetic core; 701. Temperature detection element mounting slot; 7021. First isolation plate mounting slot; 7022. Second isolation plate mounting slot; 703. Ring magnetic core positioning slot; 704. Sensor lead slot. Detailed Implementation

[0037] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0038] Example 1: Refer to Figure 3 and Figure 4 This embodiment provides an insulation fixing and over-temperature protection device for a high-frequency resonant transformer, including a first insulating clamp 7, a second insulating clamp 12, an elastic clamping member 8, a temperature sensing element 9, a U-shaped isolation plate 10, a non-metallic isolation column 11, a non-metallic fastener 13, and a toroidal magnetic core 14. The U-shaped isolation plate 10 includes a first U-shaped isolation plate and a second U-shaped isolation plate spaced apart circumferentially along the toroidal magnetic core 14. The center-tapped primary winding and secondary winding are wound on the toroidal magnetic core 14, and the high-frequency resonant inverter module is connected to the center-tapped primary winding. To highlight the relationship between the insulating clamps, the isolation plate positioning, and the temperature sensing element installation, Figures 3 to 5 The primary and secondary windings are omitted.

[0039] Reference Figure 3 and Figure 4Both the first insulating clamp 7 and the second insulating clamp 12 are plate-shaped insulating structures with a central through hole, and mounting portions for connection are provided on their periphery. The first insulating clamp 7 and the second insulating clamp 12 can be made of insulating engineering plastics, heat-resistant insulating composite materials, or other materials with electrical insulation and mechanical support capabilities. The outer surface of the toroidal magnetic core 14 is provided with an insulating encapsulation layer, which is at least one of a PBT encapsulation layer, a polyimide insulating layer, a polyester insulating layer, or a glass fiber insulating layer. The insulating encapsulation layer maintains insulation between the winding, the temperature sensing element 9, and the clamping structure and the magnetic material, preventing electrical breakdown between the winding and the magnetic material.

[0040] Reference Figures 3 to 5 The first insulating clamp 7 and the second insulating clamp 12 each have annular core positioning grooves 703 on their opposing sides. In the assembled state, the two annular core positioning grooves 703 together form a core positioning space that matches the shape of the annular core 14. The inner and outer groove walls of the annular core positioning grooves 703 restrict the radial movement of the annular core 14, and the axial limiting surfaces of the two annular core positioning grooves 703 are located on both sides of the annular core 14 axially to restrict the axial movement of the annular core 14. This positioning structure effectively limits the annular core 14 in both the axial and radial directions after assembly, preventing the core from shifting due to vibration or thermal stress during operation, thereby ensuring the stability of the transformer magnetic circuit and the reliability of the insulation distance between windings.

[0041] Reference Figure 3 and Figure 4 The first insulating clamp 7 and the second insulating clamp 12 are detachably connected by multiple non-metallic isolation posts 11 and non-metallic fasteners 13. In this embodiment, the non-metallic fasteners 13 are fixing screws. The non-metallic isolation posts 11 are located between the two insulating clamps and cooperate with the corresponding mounting parts to maintain the assembly interval between the two insulating clamps. The non-metallic fasteners 13 pass through the mounting parts and the non-metallic isolation posts 11 and lock, so that the two annular magnetic core positioning grooves 703 stably clamp the annular magnetic core 14. Optionally, the detachable connection can also adopt insulating nuts, threaded isolation posts, snaps, or combinations thereof. The setting of non-metallic isolation posts and non-metallic fasteners ensures the consistency of the spacing between the clamps on the one hand, and avoids the metal fasteners from generating eddy currents or causing magnetic circuit short circuits in the high-frequency alternating magnetic field of the annular magnetic core on the other hand, thus improving the operational safety of the device in high-temperature and high-frequency environments.

[0042] Reference Figure 5The first insulating clamping member 7, facing the annular magnetic core 14, has a temperature sensing element mounting slot 701, a first insulating plate mounting slot 7021, a second insulating plate mounting slot 7022, an annular magnetic core positioning slot 703, and a sensor lead slot 704 communicating with the temperature sensing element mounting slot 701. These slot structures are centrally located on the first insulating clamping member 7 to provide a unified reference for core positioning, insulating plate positioning, temperature sensing element positioning, and lead management. This integrated design allows each component to obtain a clear positioning reference during assembly, reducing cumulative assembly errors caused by the cooperation of multiple independent positioning components, and improving assembly efficiency and product consistency.

[0043] Reference Figure 5 The first insulating plate mounting groove 7021 and the second insulating plate mounting groove 7022 are both strip-shaped grooves extending radially along the annular magnetic core 14 and spaced apart from each other. The groove width of the first insulating plate mounting groove 7021 is greater than the thickness of the first U-shaped insulating plate, and the groove width of the second insulating plate mounting groove 7022 is greater than the thickness of the second U-shaped insulating plate, and both have assembly gaps. These assembly gaps provide necessary allowance for the insertion of the insulating plates, reducing assembly difficulty; on the other hand, after the insulating plates are embedded, the groove walls can effectively limit the circumferential movement of the insulating plates, preventing them from sliding along the circumference of the annular magnetic core 14, and also preventing the insulating plates from tilting relative to the first insulating clamp 7, ensuring the stability of the winding boundary position.

[0044] Reference Figures 3 to 5 The U-shaped insulating plate 10 is a plate-shaped insulating component consisting of two opposing arms and a connecting portion connecting the two arms. During assembly, the U-shaped insulating plate 10 does not have an independent positioning boss; instead, it is directly embedded into the corresponding insulating plate mounting groove at its end edge facing the first insulating clamping member 7. The two arms are located radially inner and radially outer on the local cross-section of the annular magnetic core 14, respectively, and the connecting portion spans one side of the annular magnetic core 14. This insulating structure has no additional positioning parts, making assembly simple. Furthermore, because the two arms of the insulating plate simultaneously clamp the magnetic core cross-section from both radially inner and outer sides, a stable circumferential boundary is formed once the position of the insulating plate on the magnetic core is determined.

[0045] The first and second U-shaped isolating plates form two dividing positions along the circumference of the toroidal core 14. The space between these two dividing positions constitutes the primary winding region, and the remaining circumferential space constitutes the secondary winding region. The first and second primary half-windings are located in the primary winding region, with one end of each half forming a center tap, and the other end connected to the alternating output terminals of the high-frequency resonant inverter module. The secondary winding is located in the secondary winding region. Through the physical separation of the two U-shaped isolating plates, the primary and secondary windings are clearly isolated circumferentially, effectively preventing them from sliding, overlapping, or approaching each other on the core. This ensures the insulation distance between the primary and secondary windings, reduces the distributed capacitance between the windings, and helps improve the electrical safety and resonant characteristic stability of the high-frequency resonant transformer.

[0046] Reference Figure 3 and Figure 5 The temperature sensing element 9 is disposed within the temperature sensing element mounting groove 701, with its temperature measuring surface facing the annular magnetic core 14. An elastic clamping member 8 is disposed on the side of the temperature sensing element 9 facing away from the annular magnetic core 14. After the first insulating clamping member 7 and the second insulating clamping member 12 are connected, the elastic clamping member 8 undergoes elastic deformation and applies a force towards the annular magnetic core 14 to the temperature sensing element 9, ensuring that the temperature sensing element 9 remains in continuous contact with the insulating encapsulation layer of the annular magnetic core 14. The groove wall of the temperature sensing element mounting groove 701 provides lateral restraint to the temperature sensing element 9, preventing lateral displacement. The continuous elastic action of the elastic clamping member 8 ensures that the temperature sensing element 9 remains in close contact with the surface of the annular magnetic core after the clamping members are connected, overcoming the problem of poor temperature contact caused by aging or peeling of the adhesive layer or changes in assembly gaps, effectively improving the real-time performance and accuracy of temperature detection.

[0047] Reference Figure 5 The temperature sensing element mounting slot 701 is connected to the sensor lead slot 704 extending to the outer edge of the first insulating clamp 7. The leads of the temperature sensing element 9 are led out along the sensor lead slot 704, and the sensor lead slot 704 is separated from the primary winding area. This lead-out method allows the leads of the temperature sensing element to be led out along an independent path, avoiding the area where the high-frequency primary winding is located, reducing the coupling interference of high-frequency strong electrical signals to the weak temperature sampling signal, and also facilitating the identification and management of the leads during assembly and maintenance.

[0048] Reference Figure 1In terms of electrical connection, the DC power supply powers the high-frequency resonant inverter module via a fuse and an input power-off component. The high-frequency resonant inverter module drives the primary winding of the center tap to work alternately and transfers energy to the secondary winding through the toroidal core 14. The control power supply is connected to the power input side of the normally open main contact of the relay in the input power-off component and supplies power to the temperature protection component. The temperature sensing element 9 detects the surface temperature of the toroidal core 14 and sends the temperature sampling signal to the temperature protection component; the temperature protection component controls the on / off state of the input power-off component according to the temperature sampling signal.

[0049] Reference Figure 2 The temperature protection component includes a sampling voltage divider unit 1, an RC filter unit 2, a threshold comparison unit, a fault latching unit 5, and a relay drive unit 6. The sampling voltage divider unit 1 includes a temperature sensing element 9 and a sampling resistor. The temperature sensing element 9 and the sampling resistor are connected in series across the control power supply, forming a temperature sampling node. The temperature sensing element 9 is an NTC thermistor, whose resistance decreases as temperature increases, causing the potential of the temperature sampling node to change accordingly with temperature. When the temperature sensing element 9 or its leads become open-circuited, the potential of the temperature sampling node reaches the potential range corresponding to the open-circuit fault, providing a basis for judgment for the subsequent sensor open-circuit comparison unit.

[0050] Reference Figure 2 RC filter unit 2 is connected between the temperature sampling node and the threshold comparison unit to attenuate the switching interference generated by the high-frequency resonant inverter module. Since the high-frequency resonant inverter module generates strong electromagnetic interference during operation, without filtering, the interference signal may be superimposed on the temperature sampling signal, causing the threshold comparison unit to malfunction. The RC filter unit filters out high-frequency noise components through low-pass filtering, improving the purity of the temperature sampling signal and ensuring the accuracy of the protection circuit's operation near the critical temperature.

[0051] Reference Figure 2 The threshold comparison unit includes a high-temperature comparison unit 3 and a sensor open-circuit comparison unit 4. The high-temperature comparison unit 3 compares the filtered temperature sampling voltage with a high-temperature reference voltage. When the temperature sampling voltage reaches the upper threshold corresponding to the high temperature, it outputs a first fault signal. The sensor open-circuit comparison unit 4 compares the filtered temperature sampling voltage with an open-circuit fault reference voltage. When the temperature sampling voltage reaches the lower threshold corresponding to an open circuit in the temperature sensing element, it outputs a second fault signal. By setting two independent comparison channels for high-temperature comparison and sensor open-circuit comparison, the protection circuit can identify both core over-temperature faults and open-circuit faults in the temperature sensing element and its leads, preventing temperature protection failure due to sensor damage.

[0052] Reference Figure 2The outputs of the high-temperature comparison unit 3 and the sensor open-circuit comparison unit 4 are each connected to the same fault setting node via unidirectional conduction elements. This fault setting node is connected to the setting terminal of the fault latching unit 5. A reset switch is connected to the reset terminal of the fault latching unit 5. Upon receiving any fault signal, the fault latching unit 5 maintains the fault state and disables the operation-allowed output. After the fault condition is cleared, the latch is released by operating the reset switch. This fault latching mechanism prevents the high-frequency resonant inverter module from repeatedly starting and stopping when the temperature of the toroidal core 14 is near the threshold, ensuring stable system operation.

[0053] Reference Figure 1 and Figure 2 The relay drive unit 6 includes a power semiconductor switch controlled by the operation enable output of the fault latching unit 5. The input power-off component includes a relay coil and a normally open main contact of the relay connected in series between the DC power supply and the high-frequency resonant inverter module. Under normal conditions, the operation enable output is valid, the power semiconductor switch is turned on and energizes the relay coil, and the normally open main contact of the relay is closed. When an abnormality occurs, such as core overheating, open circuit of the temperature detection element, or power failure of the temperature protection component, the operation enable output fails or the relay coil is de-energized, the normally open main contact of the relay is released and the DC input of the high-frequency resonant inverter module is cut off. A freewheeling branch is provided at both ends of the relay coil to absorb the induced electromotive force generated when the coil is de-energized, protecting the drive circuit.

[0054] Reference Figure 2 The temperature protection component also includes a status indicator unit to indicate normal operation, abnormal temperature, and sensor open circuit fault status. The status indicator unit includes at least one of the following: normal status indication, over-temperature status indication, and sensor open circuit fault status indication. The control power supply is connected to the power input side of the normally open main contact of the relay, ensuring that the temperature protection component remains powered even after the normally open main contact of the relay is opened, thus maintaining fault latching and status indication. This power supply method ensures that the protection circuit continues to operate after a fault occurs, allowing maintenance personnel to quickly locate the fault type through the status indicator unit.

[0055] It should be noted that the assembly process in this embodiment is as follows: First, the annular magnetic core 14 is placed in the annular magnetic core positioning groove of the second insulating clamp 12; then, the first U-shaped isolation plate and the second U-shaped isolation plate are respectively positioned across a partial cross-section of the annular magnetic core 14, and their end edges are embedded into the corresponding isolation plate mounting grooves on the first insulating clamp 7; subsequently, the temperature sensing element 9 and the elastic clamping member 8 are installed into the temperature sensing element mounting groove 701 of the first insulating clamp 7, so that the temperature measuring surface of the temperature sensing element 9 faces the annular magnetic core 14, and the sensor lead is led out along the sensor lead groove 704; finally, the first insulating clamp 7 and the second insulating clamp 12 are aligned and locked by the non-metallic isolation post 11 and the non-metallic fastener 13. The primary winding and the secondary winding can be arranged according to the area defined by the two U-shaped isolation plates before or after the clamping structure is closed. In this assembly sequence, each component can be self-positioned by the groove structure, and high-precision assembly can be completed without additional tooling, improving the efficiency of mass production.

[0056] Working Principle: The DC power supply powers the high-frequency resonant inverter module via the input power-off component. The high-frequency resonant inverter module drives the primary winding of the center tap to establish alternating magnetic flux in the toroidal core 14, while the secondary winding outputs isolated high-frequency AC power. The temperature sensing element 9, under the action of the elastic clamping member 8, continuously contacts the surface of the toroidal core 14, detecting the temperature of the toroidal core 14 in real time and sending the temperature sampling signal to the temperature protection component. When the temperature sampling signal is within the normal range, the operation permission output keeps the input power-off component conducting, and the system operates normally. When the core temperature reaches the preset protection condition, or when the temperature sensing element 9 and its leads become open-circuited, the fault signal is latched by the fault latching unit 5, causing the operation permission output to fail and the input power-off component to disconnect, cutting off the DC input of the high-frequency resonant inverter module and achieving the protection function.

[0057] It is worth noting that this invention solves the problems of unstable assembly and easy displacement of windings in high-frequency transformers through precise matching between components. Specifically, the annular magnetic core positioning grooves 703 on the first insulating clamp 7 and the second insulating clamp 12, facing each other, together form a magnetic core positioning space that can simultaneously restrict the axial and radial movement of the annular magnetic core 14, effectively avoiding the displacement problem caused by traditional binding and fixing; the two U-shaped isolation plates 10 are directly embedded in the first isolation plate mounting groove 7021 and the second isolation plate mounting groove 7022 on the first insulating clamp 7, respectively. The groove wall of the strip groove provides circumferential limiting and anti-tilting guidance for the U-shaped isolation plates 10, forming a clear and stable boundary between the primary winding area and the secondary winding area around the annular magnetic core 14, ensuring the insulation distance between the primary and secondary windings; at the same time, the temperature detection element 9 is set in the temperature detection element mounting groove 701 on the first insulating clamp 7, and works with the elastic clamping member 8 on the back side to generate continuous elastic deformation, so that the temperature detection element 9 can always be in close contact with the surface of the annular magnetic core 14, and its lead wire avoids the winding interference area through the independently led-out sensor lead wire groove 704. The above structure highly integrates core positioning, winding isolation, temperature measurement bonding, and lead management on the first insulating clamp 7, which significantly improves assembly consistency, insulation reliability, and long-term stability of temperature sampling.

[0058] Furthermore, this invention constructs an electrical protection system with multiple self-diagnostic functions and fail-safe mechanisms. The temperature protection component obtains the resistance change signal of the temperature detection element 9 through the sampling voltage divider unit 1, and effectively suppresses the switching noise interference generated by the high-frequency resonant inverter module through the RC filter unit 2; subsequently, the high temperature comparison unit 3 and the sensor open circuit comparison unit 4 can not only output a first fault signal when the magnetic core is overheated, but also output a second fault signal when the temperature detection element 9 or its lead is open-circuited, eliminating the protection blind zone caused by sensor damage; the fault latching unit 5 locks the power-off control state after receiving any fault signal, completely avoiding the problem of the relay repeatedly engaging and disengaging near the temperature threshold; the operation of the fault latching unit 5 allows the output terminal to control the gain and loss of power of the input power-off component (including the relay coil and normally open main contacts) through the relay drive unit 6. Because the normally open main contact of the relay is connected in series between the DC power supply and the high-frequency resonant inverter module, and the control power supply is connected to the power input side of the main contact, the DC input of the high-frequency resonant inverter module can be reliably cut off when the magnetic core overheats, the sensor is open-circuited, or the temperature protection component itself loses power. After power failure, the fault latch and status indication unit are continuously powered, which makes it convenient for maintenance personnel to quickly locate the fault type and comprehensively improves the safety, stability and maintainability of the system.

[0059] The above specific embodiments are merely several optional embodiments of the present invention. Based on the technical solutions of the present invention and the relevant teachings of the above embodiments, those skilled in the art can make various alternative improvements and combinations to the above specific embodiments.

Claims

1. An insulation fixing and over-temperature protection device for a high-frequency resonant transformer, characterized in that, It includes a toroidal magnetic core, a primary winding, a secondary winding, and a high-frequency resonant inverter module, characterized in that it also includes an insulating clamping assembly, a winding isolation component, a temperature detection element, an elastic clamping component, a temperature protection assembly, and an input power-off assembly; The insulating clamping assembly includes a first clamping member and a second clamping member connected to each other, forming a positioning space between them for accommodating and fixing the annular magnetic core; The winding isolation element is disposed on the annular magnetic core and is used to isolate the primary winding and the secondary winding along the circumference of the annular magnetic core. The temperature sensing element is disposed between the insulating clamping assembly and the annular magnetic core, and the elastic clamping member continuously presses the temperature sensing element against the surface of the annular magnetic core. The temperature protection component is electrically connected to the temperature detection element, and the control output terminal of the temperature protection component is connected to the control terminal of the input power-off component; the main path of the input power-off component is connected in series between the DC power supply and the high-frequency resonant inverter module, and the temperature protection component is at least used to control the input power-off component to cut off the power supply to the high-frequency resonant inverter module when there is an over-temperature or detection element failure.

2. The insulation fixing and over-temperature protection device for a high-frequency resonant transformer according to claim 1, characterized in that, The first clamping member and the second clamping member have annular positioning grooves on their opposite sides that are adapted to the shape of the annular magnetic core. In the assembled state, the two annular positioning grooves together form the positioning space to restrict the axial and radial movement of the annular magnetic core.

3. The insulation fixing and over-temperature protection device for a high-frequency resonant transformer according to claim 1, characterized in that, The insulating clamping assembly is provided with an isolator mounting groove. The winding isolator is a U-shaped partition. The end of the U-shaped partition is directly embedded in the isolator mounting groove, and its movement along the circumference of the annular magnetic core or its tilt relative to the insulating clamping assembly is restricted by the groove wall of the isolator mounting groove. The mounting groove for the isolator is a strip-shaped groove extending radially along the annular magnetic core. The width of the strip-shaped groove is greater than the thickness of the U-shaped partition to allow for assembly clearance.

4. The insulation fixing and over-temperature protection device for a high-frequency resonant transformer according to claim 1, characterized in that, The primary winding is a center-tapped primary winding, including a first primary half-winding and a second primary half-winding with the same number of turns; one end of the first primary half-winding and the second primary half-winding together form a center tap, and the other end is respectively connected to the two alternating output terminals of the high-frequency resonant inverter module.

5. The insulation fixing and over-temperature protection device for a high-frequency resonant transformer according to claim 1, characterized in that, The first or second clamping member is provided with a temperature sensing element mounting slot and a sensor lead slot communicating with the temperature sensing element mounting slot; the temperature sensing element is installed in the temperature sensing element mounting slot, and its lead is independently led out along the sensor lead slot to avoid the primary winding area.

6. The insulation fixing and over-temperature protection device for a high-frequency resonant transformer according to claim 1, characterized in that, The temperature sensing element is an NTC thermistor, and the elastic clamping component is a heat-resistant elastic silicone block or a heat-resistant elastic foam.

7. The insulation fixing and over-temperature protection device for a high-frequency resonant transformer according to claim 1, characterized in that, The temperature protection component includes a sampling voltage divider unit, an RC filter unit, a threshold comparison unit, a fault latch unit, and a relay drive unit; the sampling voltage divider unit is connected to the threshold comparison unit via the RC filter unit, the fault output terminal of the threshold comparison unit is connected to the fault set terminal of the fault latch unit, and the operation enable output terminal of the fault latch unit is connected to the relay drive unit. The threshold comparison unit includes a high temperature comparison unit and a sensor open circuit comparison unit, which are respectively used to output a first fault signal or a second fault signal when the temperature sampling voltage reaches the high temperature threshold or the threshold corresponding to the open circuit of the detection element. The first fault signal and the second fault signal are connected to the fault set terminal of the fault latch unit via a signal merging branch. The fault latching unit is connected to a reset switch and maintains a power-off control state after receiving any fault signal until the fault condition is cleared and a reset signal is received.

8. The insulation fixing and over-temperature protection device for a high-frequency resonant transformer according to claim 7, characterized in that, The input power-off component includes a relay coil and a normally open main contact of the relay connected in series between the DC power supply and the high-frequency resonant inverter module; the relay drive unit controls the energization and de-energization of the relay coil according to the operation permission output terminal. Under normal conditions, the relay coil is energized to close the normally open main contacts. In the event of a fault or when the temperature protection component is de-energized, the relay coil is de-energized to open the normally open main contacts. The temperature protection component further includes a status indication unit, which includes at least one of a normal status indication, an over-temperature status indication, and a sensor open-circuit fault status indication.

9. An insulation fixing and over-temperature protection device for a high-frequency resonant transformer according to claim 1, wherein the temperature protection component is powered by a control power supply, and the input terminal of the control power supply is connected to the power input side of the normally open main contact of the relay, so as to keep the temperature protection component continuously powered after the normally open main contact of the relay is opened.

10. An insulation fixing and over-temperature protection device for a high-frequency resonant transformer according to claim 1, wherein the outer surface of the annular magnetic core is provided with an insulating encapsulation layer, and the insulating encapsulation layer is at least one of PBT encapsulation layer, polyimide insulating layer, polyester insulating layer, and glass fiber insulating layer.

Images