Wide-voltage self-adaptive heating system, control method thereof and heating electric appliance

Abstract

The invention relates to a wide-voltage self-adaptive heating system, a control method thereof and a heating electric appliance. The wide-voltage self-adaptive heating system comprises a voltage identification module connected with an external power supply, a control module connected with the voltage identification module, a switch module connected with the control module and a heating module connected with the switch module and the control module, the control module outputs a control signal according to a voltage detection signal, and the control module outputs the control signal according to the voltage detection signal. A first switch element, a second switch element and a third switch element in the switch module respectively respond to a control signal so as to perform closing operation or opening operation, and the heating module presents a series topological structure or a parallel topological structure under the action of the first switch element, the second switch element and the third switch element; in this way, the output power or temperature is kept basically unchanged, and normal work under different standard power supply voltages is achieved.

Description

Technical Field

[0001] This application relates to the field of electrical equipment technology, and in particular to a wide voltage adaptive heating system and its control method, and a heating appliance. Background Technology

[0002] Existing heating appliances, such as hair dryers, space heaters, water heaters, or infrared therapy devices, typically use heating elements with fixed impedance to generate heat. However, due to differences in standard power supply voltages in different locations, the temperature or output power of these heating appliances fluctuates greatly under different standard power supply voltages, resulting in significant limitations in their use. Summary of the Invention

[0003] Therefore, it is necessary to provide a wide-voltage adaptive heating system and its control method, as well as a heating appliance, that can operate normally under different standard power supply voltages, in response to the above-mentioned technical problems.

[0004] In a first aspect, this application provides a wide voltage adaptive heating system, comprising:

[0005] The voltage identification module connects to an external power supply. It is used to identify the output voltage of the external power supply and output a voltage detection signal.

[0006] The control module is connected to the voltage recognition module. The control module is used to output control signals based on the voltage detection signal.

[0007] A switching module includes a first switching element, a second switching element, and a third switching element that are respectively connected to a control module. The first switching element, the second switching element, and the third switching element respond to a control signal to perform a closing operation or a opening operation. One end of the first switching element, one end of the second switching element, and one end of the third switching element are respectively connected to an external power supply.

[0008] The heating module has a control terminal connected to a control module, a first terminal connected to the other end of a first switching element, a second terminal connected to the other end of a second switching element, and a third terminal connected to the other end of a third switching element. The heating module is used to present a series or parallel topology under the operation of the first, second, and third switching elements.

[0009] In one embodiment, the heating module includes:

[0010] A first heating unit, one end of which is connected to the other end of a first switching element, and the other end of which is connected to the other end of a second switching element;

[0011] The second heating unit has one end connected to the other end of the first heating unit and the other end of the second switching element, and the other end of the second heating unit is connected to the other end of the third switching element.

[0012] In one embodiment, the first heating unit includes:

[0013] A first heating element, one end of which is connected to the other end of a first switching element;

[0014] A normally closed temperature control switch, one end of which is connected to the other end of the first heating element, and the other end of which is connected to the other end of the second switching element;

[0015] The second heating unit includes:

[0016] The second heating element has one end connected to the other end of a normally closed temperature control switch and the other end of a second switching element.

[0017] A thermal fuse, one end of which is connected to the other end of the second heating element, and the other end of which is connected to the other end of the third switching element.

[0018] In one embodiment, the resistance of the first heating element and the resistance of the second heating element are equal.

[0019] In one embodiment, the normally closed temperature control switch has an operating temperature of 110°C to 130°C.

[0020] In one embodiment, the surfaces of the first heating element and the second heating element are coated with a graphene-based composite coating.

[0021] In one embodiment, the voltage identification module includes:

[0022] A voltage divider network, connected to an external power supply, is used to sample the voltage output from the external power supply.

[0023] The rectifier and filter circuit is connected to the voltage divider network. The rectifier and filter circuit is used to rectify and filter the voltage after the voltage divider sampling.

[0024] The voltage comparator is connected to both the rectifier and filter circuit and the control module. The voltage comparator is used to compare the preset voltage with the voltage after rectification and filtering, and outputs a voltage detection signal.

[0025] In one embodiment, the first switching element, the second switching element, and the third switching element are all optocoupled isolated bidirectional thyristors or solid-state relays.

[0026] In one embodiment, the wide voltage adaptive heating system further includes:

[0027] The temperature detection module is connected to the control module. The temperature detection module is used to detect the temperature of the heating module and output the temperature signal to the control module.

[0028] In one embodiment, the wide voltage adaptive heating system further includes:

[0029] A heat dissipation module is used for heat dissipation.

[0030] The drive module is connected to both the heat dissipation module and the control module. The drive module is used to drive the heat dissipation module to start in response to the start signal output by the control module before the control module outputs the control signal.

[0031] Secondly, this application also provides a control method for a wide-voltage adaptive heating system, applied to the control module of the wide-voltage adaptive heating system as described above, the method comprising:

[0032] Based on the received voltage detection signal, determine the threshold range of the output voltage of the external power supply;

[0033] When the output voltage is within the first threshold range, a first control signal is output. The first control signal is used to instruct the first switching element, the second switching element, and the third switching element to perform a closing operation or a opening operation, so that the heating module presents a series topology under the operation of the first switching element, the second switching element, and the third switching element.

[0034] When the output voltage is within the second threshold range, a second control signal is output. The second control signal is used to instruct the first switching element, the second switching element, and the third switching element to perform a closing operation or a opening operation, so that the heating module presents a parallel topology under the operation of the first switching element, the second switching element, and the third switching element; wherein, the first threshold range is greater than the second threshold range.

[0035] In one embodiment, the method further includes:

[0036] When the output voltage crosses zero, either the first control signal or the second control signal is output.

[0037] After the first or second control signal is output, the system enters a power-off dead zone. Once the power-off dead zone ends, the system continues to output the first or second control signal.

[0038] In one embodiment, the first threshold range is greater than 150 volts, and the second threshold range is less than or equal to 150 volts.

[0039] In one embodiment, the method further includes:

[0040] The PWM signal is output to the heating module, and the PWM signal is used to instruct the heating module to adjust its own temperature.

[0041] In one embodiment, the method further includes:

[0042] The system monitors the operating parameters of the heating module in real time. If the operating parameters are not within the preset range, it outputs an alarm signal and cuts off the power. The operating parameters include temperature and operating current.

[0043] Thirdly, this application also provides a heating appliance, including the wide voltage adaptive heating system as described above.

[0044] The aforementioned wide-voltage adaptive heating system and its control method, and heating appliance, the wide-voltage adaptive heating system includes a voltage identification module connected to an external power supply, a control module connected to the voltage identification module, a switch module connected to the control module, and a heating module connected to the switch module and the control module respectively. The control module outputs a control signal based on the voltage detection signal. The first switch element, the second switch element, and the third switch element in the switch module respond to the control signal to perform a closing operation or a opening operation. Under the action of the first switch element, the second switch element, and the third switch element, the heating module presents a series topology or a parallel topology, thereby maintaining the output power or temperature basically constant, and realizing normal operation under different standard power supply voltages. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 This is a block diagram of a wide voltage adaptive heating system in one embodiment;

[0047] Figure 2 This is a schematic diagram of the heating module in one embodiment;

[0048] Figure 3 This is a schematic diagram of the voltage recognition module in one embodiment;

[0049] Figure 4 This is a schematic diagram of the switch module in one embodiment;

[0050] Figure 5 This is a schematic diagram of the equivalent circuit of the switching module and the heating module in one embodiment;

[0051] Figure 6 This is a schematic diagram of the structure of a wide voltage adaptive heating system in one embodiment;

[0052] Figure 7 This is a flowchart illustrating the control method of a wide voltage adaptive heating system in one embodiment;

[0053] Figure 8 This is a flowchart illustrating the control method of a wide-voltage adaptive heating system in another embodiment;

[0054] Figure 9 This is a schematic diagram of the structure of an infrared physiotherapy device in one embodiment;

[0055] Figure 10 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0056] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0057] It should be noted that the terms "first," "second," etc., used in this application can be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish the first element from the second element. The terms "comprising" and "having," and any variations thereof, used in this application, are intended to cover non-exclusive inclusion. The term "multiple" used in this application refers to two or more. The term "and / or" used in this application refers to one of the embodiments, or any combination of multiple embodiments.

[0058] Currently, heating appliances on the market mainly face three technical bottlenecks: ① Poor voltage adaptability: Most products use heating elements with fixed impedance, resulting in huge fluctuations in output power under different voltages (110V / 220V) (P=U 2 / R), leading to temperature instability. Existing wide-voltage solutions (such as switching power supplies) suffer from high cost, large size, and slow thermal response. ② Insufficient performance of core heating components: Rare-earth coatings are commonly used as infrared radiation materials, but their normal total emissivity has a ceiling (usually less than or equal to 0.85), low thermal conductivity, and are prone to pulverization and detachment under long-term high temperatures, resulting in rapid performance degradation. ③ Static and rigid system safety mechanisms: Traditional protection circuits (such as thermostats and fuses) are designed for fixed topologies and cannot cope with the new risks brought about by "dynamic electrical reconfiguration" in intelligent devices (such as switching arcs, logic races, short circuits, etc.).

[0059] In addition, there are three main technical paths for conventional electrical equipment to achieve wide voltage adaptability. Each path has significant drawbacks and cannot meet the comprehensive requirements of heating appliances in terms of cost, performance, and safety. Specifically: ① High-frequency switching power supply (SMPS) solution: Achieves voltage adaptability and precise power control through AC-DC-AC secondary conversion. Drawbacks: Complex circuit structure, requiring a large number of components such as transformers and inductors, resulting in high production costs and large equipment size; the high-frequency conversion process is prone to serious electromagnetic interference (EMI), affecting the operation of surrounding equipment; energy suffers efficiency loss due to multiple conversions, and the thermal response speed is slow, failing to meet the rapid heating requirements of heating appliances. ② Manual mechanical switching solution: Relies on users to manually select the appropriate voltage level through a physical switch. Drawbacks: Over-reliance on manual operation, resulting in a poor user experience; high risk of misoperation, easily leading to equipment damage due to incorrect voltage level selection; lacks intelligent seamless adaptation characteristics, failing to meet the global universality requirements of portable heating appliances. ③ Simplified electronic switching solution: Achieves voltage adaptation by controlling a relay through a voltage detection circuit to switch the heating wire tap or compensation resistor. Defects: The discrete stepped adjustment method is prone to power jumps and temperature fluctuations at the voltage critical point, affecting the heating experience; the core heating element is mostly a traditional multi-tap structure, which is not only complex in structure and has poor production consistency, but also makes it difficult to guarantee reliability in long-term use.

[0060] Furthermore, for the specific application scenarios of infrared physiotherapy devices, there are still performance bottlenecks in the core heating materials. Current mainstream products use rare earth coated heating wires, whose infrared emissivity is usually less than or equal to 0.85, resulting in limited thermal stability. Long-term high-temperature operation can easily lead to problems such as coating peeling and performance degradation, directly affecting the physiotherapy effect.

[0061] In summary, a long-standing technical challenge in this field is how to achieve fully automatic, seamless, smooth, and highly reliable wide-voltage adaptive operation within a controllable cost and complexity range, while simultaneously improving core heat dissipation efficiency.

[0062] The wide voltage adaptive heating system provided in this application embodiment has a control module that outputs a control signal based on a voltage detection signal. The first, second, and third switching elements in the switching module respond to the control signal to perform closing or opening operations, so that the heating module can flexibly switch between two basic electrical topologies: series and parallel topologies. This achieves low-cost, high-reliability wide voltage adaptation and enables normal operation under different standard supply voltages.

[0063] In one exemplary embodiment, such as Figure 1 As shown, a wide voltage adaptive heating system is provided, comprising:

[0064] The voltage identification module 110 is connected to an external power supply. The voltage identification module 110 is used to identify the output voltage of the external power supply and output a voltage detection signal.

[0065] Control module 120 is connected to voltage identification module 110. Control module 120 is used to output control signal based on voltage detection signal.

[0066] The switch module 130 includes a first switch element 132, a second switch element 134, and a third switch element 136, which are respectively connected to the control module 120. The first switch element 132, the second switch element 134, and the third switch element 136 respond to the control signal to perform a closing operation or a opening operation. One end of the first switch element 132, one end of the second switch element 134, and one end of the third switch element 136 are respectively connected to an external power supply.

[0067] The heating module 140 has a control terminal connected to the control module 120. The first terminal A of the heating module 140 is connected to the other end of the first switching element 132, the second terminal B of the heating module 140 is connected to the other end of the second switching element 134, and the third terminal C of the heating module 140 is connected to the other end of the third switching element 136. The heating module 140 is used to present a series topology or a parallel topology under the operation of the first switching element 132, the second switching element 134, and the third switching element 136.

[0068] The output voltage of the external power supply can be set according to the actual situation, and is not limited in this embodiment.

[0069] Specifically, such as Figure 1 As shown, the voltage identification module 110 identifies the output voltage of the external power supply and outputs a voltage detection signal to the control module 120. The control module 120 determines whether the external power supply is high-voltage or low-voltage based on the voltage detection signal. The control signal can be divided into a first control signal and a second control signal. When the external power supply is high-voltage, the control module 120 outputs the first control signal to the switch module 130. When the external power supply is low-voltage, the control module 120 outputs the second control signal to the switch module 130. The first switch element 132, the second switch element 134, and the third switch element 136 in the switch module 130 respond to the control signal to perform a closing operation or a opening operation. At the same time, the heating module 140 is used to present a series topology or a parallel topology under the operation of the first switch element 132, the second switch element 134, and the third switch element 136. It can be understood that by reconstructing the structure and topology switching logic of the heating module 140, only three switch elements are needed, the structure is simple, and low-cost, high-reliability wide voltage adaptive design is achieved.

[0070] It is understandable that by adopting the "load adaptive" concept, that is, without changing the input power supply, the internal connection mode (series / parallel switching) of the heating element network (heating module 140) is dynamically changed through the intelligent switching matrix (switching module 130), so that its equivalent impedance is adjusted in reverse with the input voltage, thereby achieving constant power output. Specifically, after the system is powered on, the voltage identification module 110 first accurately detects the input AC voltage (output voltage of the external power supply) and determines the range of the output voltage (high voltage zone: greater than 150V, corresponding to 220V grid; low voltage zone: less than or equal to 150V, corresponding to 110V grid); then the control module 120 drives the intelligent topology switching matrix to perform topology reconstruction according to the voltage detection signal. Using the wide voltage adaptive heating system provided in this application, after connecting to any voltage grid in the wide range of 90V to 264V, no user operation is required. It can automatically and quickly complete voltage identification and working status adjustment, maintain the output power or temperature basically constant, and achieve seamless global grid adaptation.

[0071] For example, when the external power supply is high voltage, the control module 120 outputs a first control signal to the switch module 130. The first switch element 132, the second switch element 134, and the third switch element 136 respond to the first control signal to perform a closing operation or a opening operation. The heating module 140 presents a series topology under the operation of the first switch element 132, the second switch element 134, and the third switch element 136. When the external power supply is low voltage, the control module 120 outputs a second control signal to the switch module 130. The first switch element 132, the second switch element 134, and the third switch element 136 respond to the second control signal to perform a closing operation or a opening operation. The heating module 140 presents a parallel topology under the operation of the first switch element 132, the second switch element 134, and the third switch element 136.

[0072] It should be noted that the switching elements are preferably optocoupler-isolated bidirectional thyristors or solid-state relays, which have the characteristics of high voltage resistance, fast response, and long life, ensuring long-term stable operation of the system. The first switching element 132, the second switching element 134, and the third switching element 136 can be AQC3323 solid-state relays (SSRs), with a voltage rating of 600V and a rated current of 5A. They have contactless switching characteristics, fast response speed, and no mechanical wear. The control module 120 can adopt an STC8G series microcontroller, which has high integration and low power consumption, and can realize core functions such as voltage judgment, topology switching logic control, zero-crossing detection, and PID (Proportional-Integral-Derivative Controller) constant temperature control.

[0073] In this embodiment, by designing an integrated heating module with three external terminals and a simplified switching module, intelligent switching between two basic electrical topologies, namely "series-parallel," can be achieved. This constructs a core physical foundation that differs from existing solutions, significantly reducing hardware costs and complexity. While maintaining output power or temperature essentially unchanged, it enables a wide-voltage adaptive heating system to operate normally under different standard power supply voltages.

[0074] In one embodiment, such as Figure 2 As shown, the heating module includes:

[0075] A first heating unit, one end of which is connected to the other end of a first switching element, and the other end of which is connected to the other end of a second switching element;

[0076] The second heating unit has one end connected to the other end of the first heating unit and the other end of the second switching element, and the other end of the second heating unit is connected to the other end of the third switching element.

[0077] Specifically, such as Figure 2 As shown, one end of the first heating unit can serve as the first end A of the heating module, the other end of the first heating unit, and one end of the second heating unit can serve as the second end B of the heating module, and the other end of the second heating unit can serve as the third end C of the heating module.

[0078] like Figure 1 As shown, in order to achieve flexible control of the equivalent topology of the heating module 140, an intelligent topology switching matrix (switch module 130) is configured, consisting of three controlled switch units (first switch element 132, second switch element 134 and third switch element 136). Each controlled switch unit corresponds one-to-one with the three terminals (A, B, C) of the heating module 140, and independently controls the on / off and connection relationship between the corresponding terminal and the live wire (L) or neutral wire (N) of the external power supply.

[0079] For example, in response to a first control signal (external power supply outputting high voltage), the first switch element 132, the second switch element 134, and the third switch element 136 respectively close, connecting terminal A to the live wire (L); the third switch element 136 closes, connecting terminal C to the neutral wire (N); the second switch element 134 remains open (floating), at which time the heating module 140 presents a series topology. In response to a second control signal (external power supply outputting low voltage), the second switch element 134 closes, connecting terminal B to the live wire (L); both the first switch element 132 and the third switch element 136 close, connecting terminals A and C to the neutral wire (N), and the heating module 140 presents a parallel topology.

[0080] In this embodiment, by setting an integrated heating module with three external terminals and a simplified switching module, intelligent switching between two basic electrical topologies, namely "series-parallel", can be achieved, constructing a core physical foundation that differs from existing solutions and significantly reducing hardware costs and complexity.

[0081] In one embodiment, such as Figure 2 As shown, the first heating unit includes:

[0082] A first heating element, one end of which is connected to the other end of a first switching element;

[0083] A normally closed temperature control switch, one end of which is connected to the other end of the first heating element, and the other end of which is connected to the other end of the second switching element;

[0084] The second heating unit includes:

[0085] The second heating element has one end connected to the other end of a normally closed temperature control switch and the other end of a second switching element.

[0086] A thermal fuse, one end of which is connected to the other end of the second heating element, and the other end of which is connected to the other end of the third switching element.

[0087] The types of the first heating element and the second heating element can be set according to the actual situation. In this embodiment, the heating element is a heating wire as an example.

[0088] Specifically, such as Figure 2As shown, one end of the first heating element R1 is fixedly connected to the first terminal A, the input terminal of the normally closed temperature control switch Kt is fixedly connected to the other end of the first heating element R1, and the output terminal of the normally closed temperature control switch Kt is fixedly connected to the second terminal B; one end of the second heating element R2 is fixedly connected to the second terminal B, the input terminal of the thermal fuse F is fixedly connected to the other end of the second heating element R2, and the output terminal of the thermal fuse F is fixedly connected to the third terminal C.

[0089] For example, at room temperature, the normally closed temperature control switch Kt is in the closed state, and the first terminal A to the third terminal C form a connection via... The continuous electrical path has an equivalent resistance that is approximately the series resistance of R1 and R2. The normally closed temperature control switch Kt and the thermal fuse F are integrated into the heating module as safety protection components, requiring no external configuration and greatly improving the system integration and operational reliability.

[0090] It should be noted that the heating module is housed in an integrated package, which is made of high-temperature resistant ceramic.

[0091] In one embodiment, the resistance of the first heating element and the resistance of the second heating element are equal.

[0092] Specifically, in order to achieve constant power output over a wide voltage range, the resistance values ​​of the first heating element and the second heating element are equal, and the output power under high voltage conditions is equal to the output power under low voltage conditions.

[0093] For example, taking a high-voltage external power supply with an output voltage of 220V and a low-voltage external power supply with an output voltage of 110V as an example, it can be understood that the resistance R of the first heating element and the second heating element must satisfy the following formula:

[0094] ;

[0095] Taking a target design power P of 1200W as an example, it can be deduced that when R is 20Ω, the theoretical output power P of the system is approximately 1210W under both 220V high-voltage input and 110V low-voltage input. According to the GB 4706.15-2008 standard, the output power P should be within +5% or -10% of the rated function, thus meeting the requirement of achieving constant power output over a wide voltage range. This verifies from a theoretical and mathematical perspective that by changing the external connection method of the three terminals, the integrated heating module can flexibly switch between series and parallel topologies, thereby obtaining consistent heating power under significantly different input voltages, and enabling the wide-voltage adaptive heating system to operate normally under different standard supply voltages.

[0096] In this embodiment, by setting the resistance values ​​of the first heating element and the second heating element to be equal, the wide voltage adaptive heating system can accurately output constant power at both high and low voltage levels, with fast thermal response and no temperature fluctuation.

[0097] In one embodiment, the normally closed temperature control switch has an operating temperature of 110°C to 130°C.

[0098] Specifically, the normally closed temperature control switch has an operating temperature of 110°C to 130°C to ensure the structural stability of the heating module under high-temperature conditions.

[0099] In one embodiment, the surfaces of the first heating element and the second heating element are coated with a graphene-based composite coating.

[0100] Specifically, by applying a high-performance graphene-based composite coating to the surfaces of the first and second heating elements, tests show that the coating has a normal total emissivity of up to 0.83, which is superior to conventional rare earth coatings. It also has a high thermal conductivity of more than 1500 W / m·K, enabling rapid heat conduction and heating. Furthermore, it exhibits excellent chemical stability and coating adhesion strength, allowing it to withstand high-temperature working environments for extended periods and preventing performance degradation.

[0101] It should be noted that the high thermal conductivity of the graphene-based composite coating ensures that the heat generated by the heating element is quickly and evenly transferred to the coating surface, significantly improving the thermal response speed after topology switching; its high infrared emissivity and stability ensure that the heating element can emit far-infrared rays efficiently and continuously in any topology mode, fully transforming the advantages of intelligent power control into improved actual therapeutic effects, achieving the dual goals of "precise temperature control" and "highly efficient therapy".

[0102] In practical applications, industrial-grade thin-layer graphene nanosheets (carbon content greater than 99%, sheet diameter 1-10μm) can be used. These are mixed with a specific dispersant and deionized water at a ratio of 20wt%, and dispersed by high-speed shearing to prepare an aqueous graphene slurry (such as model XJ-202). This slurry is then coated onto the surfaces of the first and second heating elements using a standard "pretreatment-coating-curing" process, resulting in a uniform coating thickness and strong adhesion.

[0103] In this application, by innovating the heating element material and abandoning the traditional rare earth coating, a graphene-based composite coating is creatively applied to the surface of the heating element, which greatly improves the infrared conversion efficiency and thermal stability.

[0104] In one embodiment, the voltage identification module includes:

[0105] A voltage divider network, connected to an external power supply, is used to sample the voltage output from the external power supply.

[0106] The rectifier and filter circuit is connected to the voltage divider network. The rectifier and filter circuit is used to rectify and filter the voltage after the voltage divider sampling.

[0107] The voltage comparator is connected to both the rectifier and filter circuit and the control module. The voltage comparator is used to compare the preset voltage with the voltage after rectification and filtering, and outputs a voltage detection signal.

[0108] The preset voltage can be set according to the actual situation, and is not limited in this embodiment.

[0109] Specifically, such as Figure 3 As shown, the voltage identification module includes an AC voltage detection circuit with hysteresis. It uses a high-resistance voltage divider network (such as 2MΩ+100kΩ) to sample the voltage, and after precision rectification and filtering, it is input to a voltage comparator (model LM393) with hysteresis function. The comparison threshold is set to the equivalent DC voltage (preset voltage) of AC 150V to ensure accurate voltage identification without jitter.

[0110] In one embodiment, the first switching element, the second switching element, and the third switching element are all optocoupled isolated bidirectional thyristors or solid-state relays.

[0111] Specifically, the first, second, and third switching elements are preferably optocoupler-isolated bidirectional thyristors or solid-state relays, which have the characteristics of high voltage resistance, fast response, and long life, and can ensure the long-term stable operation of the system.

[0112] It should be noted that the drive circuits of each controlled switch unit (first switch element, second switch element and third switch element) are equipped with auxiliary contact status feedback loops. After the control module sends out a control signal, it must accurately receive the corresponding feedback signal to confirm that the switching is successful, so as to avoid malfunctions caused by incorrect switching.

[0113] For example, to facilitate understanding by those skilled in the art, the switching module is described below with reference to a specific example, such as... Figure 4 As shown, the control module can be a logic control unit (MCU, Microcontroller Unit), the heating module can be a three-terminal topology variable heating module, Kt represents the normally closed temperature control switch in the heating module, F represents the thermal fuse in the heating module, R1 represents the first heating unit, and R2 represents the second heating unit. The first, second, and third switching elements are illustrated using an AQC3323 solid-state relay (single-pole double-throw switch unit) as an example.

[0114] It should be noted that, as Figure 4 As shown, the logic control unit is connected to the first switching element K. A Control terminal (CTRL)A ), second switching element K B Control terminal (CTRL) B ) and the third switching element K C Control terminal (CTRL) C ).

[0115] like Figure 4 As shown, under high voltage (220V input), the heating module exhibits a series topology: ① Connection logic: First switching element K A The operation is closed, connecting terminal A to the live power wire (L); the third switching element K C The operation is closed, connecting terminal C to the power supply neutral line (N); the second switching element K B ① Keep it disconnected (floating). ② Current path: such as Figure 5 As shown in the left figure, current flows from the live wire (L) through the first switching element K. A The water flows into terminal A and passes through in sequence. Then through the third switching element K C The current flows back to the neutral line (N) from terminal C. ③ Equivalent topology: The first heating element R1 and the second heating element R2 are connected in series. If R1=R2=R, then the total equivalent resistance R in series = 2R. ④ Output power: .

[0116] In low-voltage mode (110V input), the heating module exhibits a parallel topology: ① Connection logic: Second switching element K B The operation is closed, connecting terminal B to the live power wire (L); the first switching element K A Third switching element K C Both terminals close automatically, connecting terminals A and C to the neutral (N) wire. ② Current path: (e.g., ...) Figure 5 As shown in the right figure, current flows from the live wire (L) through the second switching element K. B The water flows into terminal B, where it splits into two paths: one path flows through... Flow back to the neutral line (N); another path Return to neutral (N). ③ Equivalent topology: The branch containing the first heating element R1 (including the normally closed temperature control switch Kt) and the branch containing the second heating element R2 (including the thermal fuse F) are connected in parallel. If R1=R2=R, then the total equivalent resistance R in parallel = R / 2. ④ Output power: .

[0117] It should be noted that the software layer of the control module has preset logic to prohibit dangerous connection combinations, such as strictly prohibiting the first switching element K. A With the second switching element K B Simultaneously connecting to the live wire (L) avoids short-circuit risks from the logical root cause.

[0118] In one embodiment, the wide voltage adaptive heating system further includes:

[0119] The temperature detection module is connected to the control module. The temperature detection module is used to detect the temperature of the heating module and output the temperature signal to the control module.

[0120] Specifically, the temperature detection module can detect the temperature of the heating module and each branch in real time (through infrared thermometry or contact sensors), and output the monitored temperature signal to the control module. Based on the temperature signal, the control module immediately determines the fault (such as open circuit of heating wire, relay sticking, etc.) when abnormal temperature distribution is detected, and quickly starts the protection program (cuts off power and issues alarm signal) to ensure the safety of equipment and users.

[0121] For example, the wide voltage adaptive heating system may also include a current detection module for real-time detection of the total current and outputting a current signal to the control module. If the control module detects that the current deviates from the theoretical value of the current topology by more than a threshold, it immediately determines that there is a fault and quickly starts the protection program to ensure the safety of the equipment and the user.

[0122] In one embodiment, the wide voltage adaptive heating system further includes:

[0123] A heat dissipation module is used for heat dissipation.

[0124] The drive module is connected to both the heat dissipation module and the control module. The drive module is used to drive the heat dissipation module to start in response to the start signal output by the control module before the control module outputs the control signal.

[0125] The components within the heat dissipation module can be configured according to actual conditions. In this embodiment, the heat dissipation module includes a cooling fan as an example.

[0126] Specifically, before the drive switch module operates, the control module first drives the heat dissipation module to start the cooling fan, and then performs topology switching after confirming that the cooling fan is operating normally. That is, the control signal is output only after confirming that the cooling fan is operating normally.

[0127] It should be noted that by strictly following the principle of "voltage detection first" Restart the fan The timing logic of "powering on the fan after it is running normally" eliminates the risk of the heating module burning out at the source.

[0128] To facilitate understanding of wide-voltage adaptive heating systems by those skilled in the art, a specific example is provided below to illustrate the concept. Figure 6As shown, the voltage identification module includes an AC input and an EMI filter, a rectifier and a DC bus, the control module can be a main control microprocessor, the switching module can be an intelligent topology switching matrix, and the heating module can be a three-terminal topology variable heating element module.

[0129] like Figure 6 As shown, through an extremely simple hardware structure design, it achieves constant power output performance comparable to high-end high-frequency switching power supply solutions, while possessing reliability and safety far exceeding existing simple electronic switching solutions. It not only perfectly solves the core challenges of global voltage adaptation and constant temperature output for heating appliances, but its core design concept of "variable three-terminal topology" can also be widely applied to various resistance heating appliances such as hair dryers, space heaters, and instant water heaters, possessing extremely high industrialization value and broad commercial prospects.

[0130] It should be noted that the three-terminal topology variable heating element module is a customized integrated model. The resistance of the first heating element and the second heating element is 20.0Ω±1% (precisely wound with nickel-chromium alloy wire to ensure consistent resistance). The normally closed temperature control switch Kt has an operating temperature of 120℃, and the thermal fuse F has a rated current of 10A. The whole system is encapsulated with a high-temperature resistant ceramic frame to ensure structural stability in high-temperature environments.

[0131] In one exemplary embodiment, such as Figure 7 As shown, a control method for a wide-voltage adaptive heating system is provided, applied to the control module of the wide-voltage adaptive heating system as described above. The method includes:

[0132] S702 determines the threshold range of the output voltage of the external power supply based on the received voltage detection signal.

[0133] Specifically, the voltage identification module identifies the output voltage of the external power supply and outputs a voltage detection signal to the control module. Based on the voltage detection signal, the control module determines whether the external power supply is high voltage or low voltage, that is, determines the threshold range of the output voltage of the external power supply.

[0134] S704 When the output voltage is in the first threshold range, a first control signal is output. The first control signal is used to instruct the first switching element, the second switching element and the third switching element to perform a closing operation or a opening operation, so that the heating module presents a series topology under the operation of the first switching element, the second switching element and the third switching element.

[0135] The range of the first threshold interval can be set according to the actual situation. In this embodiment, the first threshold interval is greater than 150 volts for illustration.

[0136] Specifically, when the output voltage is in the first threshold range, it can be understood that the external power supply is high voltage at this time. The control module outputs the first control signal to the switching module. The first switching element, the second switching element and the third switching element respond to the first control signal to perform a closing operation or a opening operation. The heating module presents a series topology structure under the action of the first switching element, the second switching element and the third switching element.

[0137] S706, when the output voltage is in the second threshold range, outputs a second control signal, the second control signal is used to instruct the first switching element, the second switching element and the third switching element to perform a closing operation or a opening operation respectively, so that the heating module presents a parallel topology structure under the operation of the first switching element, the second switching element and the third switching element; wherein, the first threshold range is greater than the second threshold range.

[0138] The range of the second threshold interval can be set according to the actual situation. In this embodiment, the second threshold interval is less than or equal to 150 volts for illustration.

[0139] Specifically, when the output voltage is in the second threshold range, it can be understood that the external power supply is at a low voltage. The control module outputs a second control signal to the switching module. The first switching element, the second switching element, and the third switching element respond to the second control signal to perform a closing operation or a opening operation. The heating module presents a parallel topology structure under the action of the first switching element, the second switching element, and the third switching element.

[0140] In the control method of the above-mentioned wide voltage adaptive heating system, the first, second, and third switching elements in the switching module respond to the control signal to perform closing or opening operations. Under the action of the first, second, and third switching elements, the heating module presents a series or parallel topology to maintain the output power or temperature basically constant, so as to achieve normal operation under different standard supply voltages.

[0141] In one embodiment, the method further includes:

[0142] When the output voltage crosses zero, either the first control signal or the second control signal is output.

[0143] After the first or second control signal is output, the system enters a power-off dead zone. Once the power-off dead zone ends, the system continues to output the first or second control signal.

[0144] Specifically, when the control module detects that the output voltage has crossed zero, it sends a first control signal or a second control signal at the zero-crossing moment. The first, second, and third switching elements in the switching module respond to the control signal to perform a closing or opening operation, respectively. At the same time, the control module verifies whether the connection has been successfully established through the state feedback loop of the switching elements to ensure that the topology reconstruction is correct.

[0145] During the interval between the "disconnect old connection" and "establish new connection" instructions, that is, before the first or second control signal needs to be output again after the first or second control signal is output, a millisecond-level "full power-off dead zone" is forcibly inserted to completely avoid the instantaneous danger of power short circuit or load open circuit.

[0146] In one embodiment, the first threshold range is greater than 150 volts, and the second threshold range is less than or equal to 150 volts.

[0147] In one embodiment, the method further includes:

[0148] The PWM signal is output to the heating module, and the PWM signal is used to instruct the heating module to adjust its own temperature.

[0149] Specifically, the control module can collect the temperature signal of the air outlet in real time through the temperature detection module, and fine-tune the power supply duty cycle of the heating module through the PID algorithm to accurately stabilize the air outlet temperature at the set value (such as 55℃) to ensure user comfort.

[0150] In one embodiment, the method further includes:

[0151] The system monitors the operating parameters of the heating module in real time. If the operating parameters are not within the preset range, it outputs an alarm signal and cuts off the power. The operating parameters include temperature and operating current.

[0152] Specifically, the control module monitors the total current and the temperature of each branch in real time through the temperature detection module and the voltage detection module (which can be achieved through infrared temperature measurement or contact sensors). If the detected operating current deviates from the theoretical value of the current topology by more than the threshold, or the temperature distribution is abnormal, it is immediately determined to be a fault (such as the heating wire being open-circuited, the relay sticking, etc.), and the protection program is quickly activated (power is cut off and an alarm signal is issued) to ensure the safety of the equipment and the user.

[0153] To facilitate understanding by those skilled in the art, the control method of a wide-voltage adaptive heating system is explained below with reference to a specific example, such as... Figure 8 As shown, the example is a control module consisting of an MCU, and the first, second, and third switching elements are all solid-state relays.

[0154] Step 1 (Safe Power-On Initialization): The user connects the device (an infrared physiotherapy device equipped with a wide voltage adaptive heating system) to a power source (such as a US 110V power grid). After the MCU powers on, it completes system initialization and controls all solid-state relays (SSRs) to be in the off state. At the same time, the voltage recognition module is activated to detect the input voltage and determine that the input voltage is in "low voltage mode" (second threshold range).

[0155] Step 2 (Heat Dissipation System Startup): The MCU outputs a drive signal to start the cooling fan motor, while waiting for feedback signals that the fan is running normally (such as detecting the fan speed through a Hall sensor).

[0156] Step 3 (Topology Reconstruction and Verification): After receiving the fan ready signal, the MCU detects the AC voltage zero-crossing point and issues a switching command at the zero-crossing point: drives the second switching element to close, connecting terminal B to the live wire (L); drives the first and second switching elements to close, connecting terminals A and C to the neutral wire (N); at the same time, verifies whether the connection is successfully established through the status feedback loop to ensure that the topology reconstruction is correct.

[0157] Step 4 (Constant Power Heating Operation): After the topology reconstruction is completed, the current is turned on, and the first heating element and the second heating element work in parallel topology with a total equivalent resistance of about 10Ω and an output power of about 1210W; the graphene-based composite coating heats up rapidly and emits far-infrared rays efficiently to meet the needs of physiotherapy.

[0158] Step 5 (PID Intelligent Thermostatic Control): The MCU collects feedback signals from the air outlet temperature sensor in real time, and fine-tunes the duty cycle of the heating element power supply through the PID algorithm to accurately stabilize the air outlet temperature at the set value (such as 55℃) to ensure the comfort of physiotherapy.

[0159] Step 6 (Full-process safety monitoring and adaptive switching): The safety interlock mechanism runs in the background throughout the process, monitoring the current and temperature status in real time. If the user takes the device to China and connects it to the 220V power grid, the system will automatically identify the voltage and switch to the series topology when the device is powered on again. The workflow is the same as the low-voltage mode, with fully automatic and seamless switching, constant and stable temperature. The device is compact, cost-effective, and always provides users with a constant temperature and safe physiotherapy experience.

[0160] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages in other steps. It is understood that the steps in different embodiments can be freely combined as needed, and all non-contradictory solutions formed by such combinations are within the scope of protection of this application.

[0161] Based on the same inventive concept, this application also provides a control device for a wide-voltage adaptive heating system, used to implement the control method of the wide-voltage adaptive heating system described above. The solution provided by this device is similar to the solution described in the above method; therefore, the specific limitations in one or more embodiments of the control device for a wide-voltage adaptive heating system provided below can be found in the limitations of the control method for the wide-voltage adaptive heating system described above, and will not be repeated here.

[0162] In one exemplary embodiment, a control device for a wide voltage adaptive heating system is provided, applied to the control module of the wide voltage adaptive heating system as described above. The device includes:

[0163] The interval division module is used to determine the threshold interval of the output voltage of the external power supply based on the received voltage detection signal.

[0164] The output module is used to output a first control signal when the output voltage is in a first threshold range. The first control signal is used to instruct the first switching element, the second switching element and the third switching element to perform a closing operation or a opening operation, so that the heating module presents a series topology under the operation of the first switching element, the second switching element and the third switching element.

[0165] The output module is also used to output a second control signal when the output voltage is in the second threshold range. The second control signal is used to instruct the first switching element, the second switching element and the third switching element to perform a closing operation or a opening operation, so that the heating module presents a parallel topology structure under the operation of the first switching element, the second switching element and the third switching element; wherein, the first threshold range is greater than the second threshold range.

[0166] In one embodiment, the output module is further configured to output a first control signal or a second control signal when a zero-crossing point of the output voltage is detected;

[0167] After the first or second control signal is output, the system enters a power-off dead zone. Once the power-off dead zone ends, the system continues to output the first or second control signal.

[0168] In one embodiment, the first threshold range is greater than 150 volts, and the second threshold range is less than or equal to 150 volts.

[0169] In one embodiment, the output module is further configured to output a PWM signal to the heating module, the PWM signal being used to instruct the heating module to adjust its own temperature.

[0170] In one embodiment, the output module is also used to monitor the operating parameters of the heating module in real time. If the operating parameters are not within the preset range, an alarm signal is output and the power is cut off. The operating parameters include temperature and operating current.

[0171] Each module in the control device of the aforementioned wide-voltage adaptive heating system can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in the processor of a computer device in hardware form or independent of it, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0172] In one exemplary embodiment, a heating appliance is provided, including the wide voltage adaptive heating system as described above.

[0173] Specifically, let's take an infrared therapy device as an example to illustrate this. Figure 9 As shown, the voltage identification module, switch module, and control module can be mounted on the circuit board, and the heating module is the heating element assembly.

[0174] In one exemplary embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 10As shown, this computer device includes a processor, memory, input / output (I / O) interfaces, and a communication interface. The processor, memory, and I / O interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the I / O interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides the environment for the operating system and computer programs in the non-volatile storage media to run. The database stores data corresponding to different threshold ranges. The I / O interfaces are used for exchanging information between the processor and external devices. The communication interface is used for communicating with external terminals via a network connection. When the computer program is executed by the processor, it implements a control method for a wide-voltage adaptive heating system.

[0175] Those skilled in the art will understand that Figure 10 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0176] In one exemplary embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the control method of the wide voltage adaptive heating system described above.

[0177] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the control method of the wide voltage adaptive heating system described above.

[0178] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the control method of the wide voltage adaptive heating system described above.

[0179] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0180] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, artificial intelligence (AI) processors, etc., and are not limited to these.

[0181] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0182] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A wide voltage adaptive heating system, characterized in that, include: A voltage identification module is connected to an external power supply. The voltage identification module is used to identify the output voltage of the external power supply and output a voltage detection signal. The control module is connected to the voltage recognition module, and the control module is used to output a control signal based on the voltage detection signal; A switching module includes a first switching element, a second switching element, and a third switching element, which are respectively connected to the control module. The first switching element, the second switching element, and the third switching element respond to the control signal to perform a closing operation or a opening operation. One end of the first switching element, one end of the second switching element, and one end of the third switching element are respectively connected to the external power supply. A heating module, wherein the control terminal of the heating module is connected to the control module, the first terminal of the heating module is connected to the other terminal of the first switching element, the second terminal of the heating module is connected to the other terminal of the second switching element, and the third terminal of the heating module is connected to the other terminal of the third switching element. The heating module is used to present a series topology or a parallel topology under the operation of the first switching element, the second switching element and the third switching element.

2. The wide voltage adaptive heating system according to claim 1, characterized in that, The heating module includes: A first heating unit, one end of which is connected to the other end of the first switching element, and the other end of which is connected to the other end of the second switching element; The second heating unit has one end connected to the other end of the first heating unit and the other end of the second switching element, and the other end of the second heating unit is connected to the other end of the third switching element.

3. The wide voltage adaptive heating system according to claim 2, characterized in that, The first heating unit includes: A first heating element, one end of which is connected to the other end of the first switching element; A normally closed temperature control switch, one end of which is connected to the other end of the first heating element, and the other end of which is connected to the other end of the second switching element; The second heating unit includes: The second heating element, one end of which is connected to the other end of the normally closed temperature control switch and the other end of the second switching element; A thermal fuse, one end of which is connected to the other end of the second heating element, and the other end of which is connected to the other end of the third switching element.

4. The wide voltage adaptive heating system according to claim 3, characterized in that, The resistance of the first heating element and the resistance of the second heating element are equal.

5. The wide voltage adaptive heating system according to claim 3, characterized in that, The normally closed temperature control switch has an operating temperature of 110°C to 130°C.

6. The wide voltage adaptive heating system according to claim 3, characterized in that, The surfaces of the first heating element and the second heating element are coated with a graphene-based composite coating.

7. The wide voltage adaptive heating system according to claim 1, characterized in that, The voltage identification module includes: A voltage divider network is connected to the external power supply, and the voltage divider network is used to sample the voltage output by the external power supply. A rectifier and filter circuit is connected to the voltage divider network. The rectifier and filter circuit is used to rectify and filter the voltage after the voltage divider sampling is completed. A voltage comparator is connected to the rectifier and filter circuit and the control module, respectively. The voltage comparator is used to compare the preset voltage with the voltage after rectification and filtering, and output the voltage detection signal.

8. The wide voltage adaptive heating system according to claim 1, characterized in that, The first switching element, the second switching element, and the third switching element are all optocoupler-isolated bidirectional thyristors or solid-state relays.

9. The wide voltage adaptive heating system according to claim 1, characterized in that, The wide voltage adaptive heating system also includes: A temperature detection module is connected to the control module. The temperature detection module is used to detect the temperature of the heating module and output a temperature signal to the control module.

10. The wide voltage adaptive heating system according to claim 1, characterized in that, The wide voltage adaptive heating system also includes: A heat dissipation module is used for heat dissipation. A drive module is connected to the heat dissipation module and the control module respectively. The drive module is used to drive the heat dissipation module to start in response to the start signal output by the control module before the control module outputs the control signal.

11. A control method for a wide voltage adaptive heating system, characterized in that, The method, applied to a control module in a wide voltage adaptive heating system as described in any one of claims 1 to 10, comprises: Based on the received voltage detection signal, determine the threshold range of the output voltage of the external power supply; When the output voltage is within the first threshold range, a first control signal is output. The first control signal is used to instruct the first switching element, the second switching element, and the third switching element to perform a closing operation or a opening operation, so that the heating module presents a series topology under the operation of the first switching element, the second switching element, and the third switching element. When the output voltage is within the second threshold range, a second control signal is output. The second control signal is used to instruct the first switching element, the second switching element, and the third switching element to perform a closing operation or a opening operation, so that the heating module presents a parallel topology under the operation of the first switching element, the second switching element, and the third switching element; wherein, the first threshold range is greater than the second threshold range.

12. The method according to claim 11, characterized in that, The method further includes: When the output voltage is detected to have crossed zero, the first control signal or the second control signal is output. After the first control signal or the second control signal is output, the system enters a power-off dead zone. The system continues to output the first control signal or the second control signal after the power-off dead zone ends.

13. The method according to claim 11, characterized in that, The first threshold range is greater than 150 volts, and the second threshold range is less than or equal to 150 volts.

14. The method according to claim 11, characterized in that, The method further includes: A PWM signal is output to the heating module, which is used to instruct the heating module to adjust its own temperature.

15. The method according to claim 11, characterized in that, The method further includes: The operating parameters of the heating module are monitored in real time. If the operating parameters are not within the preset range, an alarm signal is output and the power is cut off. The operating parameters include temperature and operating current.

16. A heating appliance, characterized in that, Including the wide voltage adaptive heating system as described in any one of claims 1 to 10.

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