Air conditioner electric heating protection method and device, storage medium and air conditioner

Abstract

This application provides a method, device, storage medium, and air conditioner for protecting the electric heating of an air conditioner. The method is applied to the controller of an electric heating protection circuit. The electric heating protection circuit also includes a duct temperature sensor and, in sequence, a power supply, a first relay, a thermal fuse, an electric heater, a temperature limiter, and a second relay. The duct temperature sensor, the first relay, and the second relay are each electrically connected to the controller. The method includes: upon receiving a working command from the electric heater, controlling the first relay and the second relay to close; acquiring the duct temperature, the fuse temperature, and the temperature limiter temperature; and controlling the first relay and the second relay to operate based on the duct temperature, the fuse temperature, and the temperature limiter temperature, so as to achieve air conditioner electric heating protection before the thermal fuse blows. This solves the problem that existing electric heating protection schemes rely on the physical characteristics of the thermal fuse for fuse protection, resulting in a long response time and untimely protection.

Description

Technical Field

[0001] This application relates to the field of air conditioner electric heating protection technology, and more specifically, to an air conditioner electric heating protection method, device, storage medium and air conditioner. Background Technology

[0002] Air conditioners that use high-power electric heaters are prone to overheating due to their high power consumption. In abnormal situations such as when the fan stops or the air outlet is blocked, high temperatures can be generated inside the machine, leading to deformation of plastic parts and even fire.

[0003] To prevent deformation and fire hazards in electric heaters during abnormal operation, protective circuits are required. Current electric heaters typically employ two types of protection devices: a resettable temperature limiter connected in series with the heater circuit, and a non-resettable or manually resettable thermal fuse connected in series with the heater circuit. For product reliability, the temperature limiter and thermal fuse usually provide initial protection to prevent the entire unit from malfunctioning after the thermal fuse trips. Existing thermal fuses generally come in two structures: bimetallic strip and alloy thermosensitive pellet. In abnormal conditions, by sensing changes in ambient temperature, the internal mechanical structure of the thermal fuse changes, causing an internal circuit break and ultimately disconnecting the electric heater. Therefore, once assembled, the characteristics of the bimetallic strip or alloy thermosensitive pellet determine that the thermal fuse's protection temperature is a single, unchangeable point. After the thermal fuse trips, neither of these types of fuses can be reset at room temperature, requiring after-sales personnel to replace the electric heater or thermal fuse, resulting in high post-fault repair costs and a long processing time. In addition, when conducting "backup protection test" (short-circuit temperature limiter), due to the limitations of the physical thermal fuse in terms of installation location and response characteristics, there are often problems such as untimely protection or excessively high protection temperature, making it difficult to meet the strict safety requirements. Furthermore, high-voltage thermal fuses are inconvenient to install in sensitive areas such as air outlets and are costly.

[0004] In summary, existing electric heating protection schemes rely on the physical characteristics of thermal fuses for fuse protection, resulting in long response times and untimely protection. Summary of the Invention

[0005] The main objective of this application is to provide an air conditioner electric heating protection method, device, storage medium, and air conditioner, so as to at least solve the problem that existing electric heating protection schemes rely on the physical characteristics of thermal fuses for fuse protection, resulting in long response times and untimely protection.

[0006] To achieve the above objectives, according to one aspect of this application, an air conditioning electric heating protection method is provided. The method is applied to a controller of an electric heating protection circuit. The electric heating protection circuit further includes a duct temperature sensor and, in sequence, a power supply, a first relay, a thermal fuse, an electric heater, a temperature limiter, and a second relay. The duct temperature sensor, the first relay, and the second relay are each electrically connected to the controller. The method includes: upon receiving an operating command from the electric heater, controlling the first relay and the second relay to close; acquiring the duct temperature, the fuse temperature, and the temperature limit temperature, wherein the duct temperature is the temperature collected by the duct temperature sensor, the fuse temperature is the temperature at which the thermal fuse melts, the temperature limit temperature is the temperature limit set by the temperature limiter, and the fuse temperature is greater than the temperature limit temperature; and controlling the first relay and the second relay to operate based on the duct temperature, the fuse temperature, and the temperature limit temperature, so as to achieve air conditioning electric heating protection before the thermal fuse melts.

[0007] Optionally, controlling the operation of the first relay and the second relay based on the duct temperature, the fuse temperature, and the temperature limit temperature includes: determining the temperature change rate of the duct temperature when the detected duct temperature is greater than or equal to the temperature limit temperature and less than the fuse temperature; controlling the first relay and the second relay to disconnect and generating fault information when the temperature change rate is greater than or equal to a change rate threshold, wherein the fault information is used to remind the user that the air conditioner inlet and outlet are blocked; and controlling the first relay and the second relay to remain closed when the temperature change rate is less than the change rate threshold.

[0008] Optionally, controlling the operation of the first relay and the second relay based on the duct temperature, the fuse temperature, and the temperature limit temperature includes: when the duct temperature is detected to be greater than or equal to the fuse temperature, controlling the first relay and the second relay to disconnect and generating fault information, wherein the fault information is used to remind the user that the air conditioner inlet and outlet are blocked.

[0009] Optionally, controlling the first relay to disconnect from the second relay includes: first controlling the first relay to disconnect, and then controlling the second relay to disconnect after the first relay has been disconnected for a first preset time period.

[0010] Optionally, upon receiving the operating command of the electric heater, controlling the first relay and the second relay to close includes: upon receiving the operating command of the electric heater, first controlling the second relay to close, and then controlling the first relay to close after the second relay has been closed for a second preset time period.

[0011] Optionally, the method further includes: upon receiving a stop-work command from the electric heater, controlling the first relay to disconnect and controlling the second relay to remain closed; after a third preset time period, acquiring the duct temperature change rate; if the duct temperature change rate is greater than or equal to a set change rate value, determining that the first relay is faulty, controlling the second relay to disconnect, and generating first relay fault information; if the duct temperature change rate is less than the set change rate value, determining that the first relay is normal, and controlling the second relay to remain closed.

[0012] Optionally, after generating fault information, the step includes: upon receiving a reset command from the electric heating protection circuit, determining that the fault has been cleared, and controlling the first relay and the second relay to resume normal operation.

[0013] According to another aspect of this application, an air conditioner electric heating protection device is provided. The device is applied to a controller of an electric heating protection circuit. The electric heating protection circuit further includes a duct temperature sensor and, in sequence, a power supply, a first relay, a thermal fuse, an electric heater, a temperature limiter, and a second relay. The duct temperature sensor, the first relay, and the second relay are each electrically connected to the controller. The device includes: a first control unit, used to control the first relay and the second relay to close when receiving a working command from the electric heater; an acquisition unit, used to acquire the duct temperature, the fuse temperature, and the temperature limit temperature, wherein the duct temperature is the temperature collected by the duct temperature sensor, the fuse temperature is the temperature at which the thermal fuse melts, the temperature limit temperature is the temperature limit set by the temperature limiter, and the fuse temperature is greater than the temperature limit temperature; and a second control unit, used to control the first relay and the second relay to operate according to the duct temperature, the fuse temperature, and the temperature limit temperature, so as to achieve air conditioner electric heating protection before the thermal fuse melts.

[0014] According to another aspect of this application, a computer-readable storage medium is provided, the computer-readable storage medium including a stored program, wherein, when the program is executed, it controls the device where the computer-readable storage medium is located to perform any of the described air conditioning electric heating protection methods.

[0015] According to another aspect of this application, an air conditioner is provided, comprising: one or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs including methods for performing any of the described air conditioner electric heating protection methods.

[0016] By applying the technical solution of this application, an air conditioning electric heating protection scheme based on multiple temperature thresholds and dual relay collaborative control is constructed, improving the system's response speed and protection reliability under abnormal operating conditions. Thermal fuses are disposable mechanical devices that require manual replacement after melting, resulting in high maintenance costs. This solution, however, utilizes a duct temperature sensor for real-time monitoring, combined with preset melting and temperature limits, to intervene in advance through a control strategy before the physical thermal fuse actually activates. Specifically, this solution can control the on / off state of the first and second relays before the thermal fuse melts due to high temperature, thereby cutting off the heating circuit. This electronic pre-protection mechanism not only solves the problems of traditional thermal fuse protection being delayed and unable to meet backup testing requirements, but also achieves definable protection temperature. Furthermore, through the series control of dual relays, it ensures that the power supply is completely cut off in emergencies, avoiding protection failure caused by a single relay malfunction, greatly improving the overall safety level of the unit under extreme conditions such as blocked air outlets, while reducing after-sales maintenance costs. This solves the problem of existing electric heating protection schemes relying on the physical characteristics of thermal fuses for melting protection, resulting in long response times and untimely protection. Attached Figure Description

[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0018] Figure 1 A hardware structure block diagram of a mobile terminal for performing an air conditioner electric heating protection method according to an embodiment of this application is shown;

[0019] Figure 2 A schematic diagram of an electric heating protection circuit provided according to an embodiment of this application is shown;

[0020] Figure 3 A schematic flowchart of an air conditioner electric heating protection method according to an embodiment of this application is shown;

[0021] Figure 4 A flowchart illustrating a specific air conditioner electric heating protection method according to an embodiment of this application is shown.

[0022] Figure 5 A control flowchart of a relay according to an embodiment of this application is shown;

[0023] Figure 6 A structural block diagram of an air conditioner electric heating protection device provided according to an embodiment of this application is shown.

[0024] The above figures include the following reference numerals:

[0025] 10. Controller; 20. Duct temperature sensor; 30. Power supply; 40. First relay; 50. Thermal fuse; 60. Electric heater; 70. Temperature limiter; 80. Second relay; 102. Processor; 104. Memory; 106. Transmission equipment; 108. Input / output device. Detailed Implementation

[0026] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0027] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0028] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0029] As described in the background section, existing electric heating protection schemes rely on the physical characteristics of thermal fuses for fuse protection, which has a long response time and results in untimely protection. To solve the problem of long response time and untimely protection in existing electric heating protection schemes that rely on the physical characteristics of thermal fuses for fuse protection, embodiments of this application provide an air conditioning electric heating protection method, device, storage medium, and air conditioner.

[0030] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0031] The methods and embodiments provided in this application can be executed on a mobile terminal, computer terminal, or similar computing device. Taking running on a mobile terminal as an example, Figure 1 This is a hardware structure block diagram of a mobile terminal for an air conditioner electric heating protection method according to an embodiment of the present invention. Figure 1 As shown, a mobile terminal may include one or more ( Figure 1 Only one is shown in the diagram. A processor 102 (which may include, but is not limited to, a microprocessor MCU or a programmable logic device FPGA, etc.) and a memory 104 for storing data are also shown. The mobile terminal may further include a transmission device 106 for communication functions and an input / output device 108. Those skilled in the art will understand that... Figure 1 The structure shown is for illustrative purposes only and does not limit the structure of the mobile terminal described above. For example, the mobile terminal may also include components that are more... Figure 1 The more or fewer components shown, or having the same Figure 1 The different configurations shown.

[0032] The memory 104 can be used to store computer programs, such as application software programs and modules, like the computer program corresponding to the air conditioner electric heating protection method in this embodiment of the invention. The processor 102 executes various functional applications and data processing by running the computer program stored in the memory 104, thereby implementing the above-described method. The memory 104 may include high-speed random access memory, and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some instances, the memory 104 may further include memory remotely located relative to the processor 102, and these remote memories can be connected to the mobile terminal via a network. Examples of the aforementioned networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof. The transmission device 106 is used to receive or send data via a network. Specific examples of the aforementioned networks may include wireless networks provided by the mobile terminal's communication provider. In one example, the transmission device 106 includes a network interface controller (NIC), which can be connected to other network devices via a base station to communicate with the Internet. In one example, the transmission device 106 may be a radio frequency (RF) module, which is used to communicate with the Internet wirelessly.

[0033] This embodiment provides a method for protecting the electric heating of an air conditioner that runs on a mobile terminal, computer terminal, or similar computing device. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0034] The air conditioner electric heating protection method is applied to the controller of the electric heating protection circuit. Figure 2This is a schematic diagram of an electric heating protection circuit provided according to an embodiment of this application, as shown below. Figure 2 As shown, the above-mentioned electric heating protection circuit also includes a duct temperature sensor 20, and a power supply 30, a first relay 40, a thermal fuse 50, an electric heater 60, a temperature limiter 70, and a second relay 80 connected in sequence. The duct temperature sensor 20, the first relay 40, and the second relay 80 are respectively electrically connected to the controller 10.

[0035] The first relay is defined as a general control relay responsible for daily on / off switching. During heating, it will frequently activate (engage and deactivate) according to the indoor temperature, and is subject to arc erosion and mechanical wear. The second relay is defined as a high-reliability thermal protector disconnect switch (electronic thermal fuse). It remains normally closed during normal heating and does not participate in daily temperature control. It only activates in the event of a serious fault (such as severe blockage of the air inlet and outlet).

[0036] Figure 3 This is a flowchart of an air conditioner electric heating protection method provided according to an embodiment of this application. For example... Figure 3 As shown, the method includes the following steps:

[0037] Step S201: Upon receiving the operating command of the electric heater, control the first relay and the second relay to close.

[0038] Step S202: Obtain the duct temperature, the fuse temperature, and the temperature limit temperature, wherein the duct temperature is the temperature collected by the duct temperature sensor, the fuse temperature is the temperature at which the thermal fuse melts, the temperature limit temperature is the temperature limit of the temperature limiter, and the fuse temperature is greater than the temperature limit temperature.

[0039] Step S203: Control the operation of the first relay and the second relay according to the above-mentioned duct temperature, the above-mentioned fuse temperature and the above-mentioned temperature limit temperature, so as to realize the air conditioner electric heating protection before the above-mentioned thermal fuse melts.

[0040] This embodiment utilizes steps S201, S202, and S203 to construct an air conditioning electric heating protection scheme based on multi-temperature threshold and dual-relay collaborative control, improving the system's response speed and protection reliability under abnormal operating conditions. Thermal fuses are disposable mechanical devices that require manual replacement after melting, resulting in high maintenance costs. This scheme, however, uses a duct temperature sensor for real-time monitoring, combined with preset melting and temperature limits, to intervene in advance through a control strategy before the physical thermal fuse actually activates. Specifically, this scheme can control the on / off state of the first and second relays before the thermal fuse melts due to high temperature, thereby cutting off the heating circuit. This electronic pre-protection mechanism not only solves the problems of traditional thermal fuse protection being lagging and unable to meet backup testing requirements, but also achieves definable protection temperature. Furthermore, the series control of the dual relays ensures that the power supply is completely cut off in emergencies, avoiding protection failure caused by a single relay malfunction, greatly improving the overall safety level of the unit under extreme conditions such as blocked air outlets, while reducing after-sales maintenance costs. This solves the problem that existing electric heating protection schemes rely on the physical properties of thermal fuses for fuse protection, resulting in long response times and untimely protection.

[0041] In the specific implementation process, the operation of the first relay and the second relay is controlled according to the aforementioned duct temperature, the aforementioned fuse temperature, and the aforementioned temperature limit temperature. This includes: when the detected duct temperature is greater than or equal to the aforementioned temperature limit temperature and less than the aforementioned fuse temperature, determining the temperature change rate of the duct temperature; when the temperature change rate is greater than or equal to the change rate threshold, controlling the first relay and the second relay to disconnect and generating fault information, wherein the fault information is used to remind the user that the air conditioner inlet and outlet are blocked; and when the temperature change rate is less than the aforementioned change rate threshold, controlling the first relay and the second relay to remain in a closed state.

[0042] In this embodiment, the protection logic is further refined, enabling graded processing of fault severity (i.e., airflow obstruction), balancing safety and user experience. Traditional protection methods often use a single temperature threshold, which is prone to false alarms or untimely protection due to temperature fluctuations or measurement errors. This solution introduces a dynamic parameter, "temperature change rate," which can more sensitively detect abnormal airflow. When the duct temperature rises but has not yet reached the melting threshold, if the temperature change rate is low, it indicates that the airflow is obstructed but still flowing, and the system determines it as a minor fault, maintaining closure to sustain heating. If the temperature change rate rises sharply, it is determined as a severe blockage (such as fan stoppage or complete closure of the outlet), heat accumulates rapidly, and the system immediately performs disconnection protection. This rate-based dynamic discrimination strategy effectively avoids false alarms caused by local hot spots or transient interference, while ensuring rapid power cut-off in truly dangerous rapid heating scenarios to prevent deformation or fire of plastic parts, achieving a balance between protection sensitivity and stability.

[0043] Specifically, controlling the operation of the first relay and the second relay based on the duct temperature, the fuse temperature, and the temperature limit temperature includes: when the duct temperature is detected to be greater than or equal to the fuse temperature, controlling the first relay and the second relay to disconnect and generating fault information, wherein the fault information is used to remind the user that the air inlet and outlet of the air conditioner are blocked.

[0044] In this embodiment, a final safety precaution is provided for extreme high-temperature conditions, ensuring absolutely reliable heat source cutoff in critical moments when conventional protection mechanisms may fail or temperatures continue to spike. When the duct temperature reaches or exceeds the physical melting temperature of the thermal fuse, it means that the accumulated heat inside has approached or reached a dangerous critical point. At this point, any delay could lead to irreversible equipment damage or even a fire. This solution specifies that at this threshold, dual relays are directly controlled to disconnect and fault information is generated. This mechanism simulates the "non-self-resettable" characteristic of traditional thermal fuses, ensuring that the circuit remains disconnected under severe fault conditions. Simultaneously, combined with the generation of fault information, timely warnings are issued to users or maintenance personnel, clarifying the nature of the fault as severe blockage or overheating, and guiding users to conduct targeted troubleshooting.

[0045] More specifically, controlling the first relay and the second relay to disconnect includes: first controlling the first relay to disconnect, and then controlling the second relay to disconnect after the first relay has been disconnected for a first preset time period.

[0046] The first preset time period can be set to 1 second.

[0047] In this embodiment, a specific relay action sequence (offset disconnection) significantly extends the lifespan of the second relay, which serves as a "safety backup," and improves the reliability of the disconnection operation. During daily air conditioning operation, the first relay is responsible for frequent temperature adjustments, and its contacts are susceptible to arcing, aging, or sticking. If the first relay sticks and cannot disconnect, the system faces serious safety hazards. This solution disconnects the first relay first, then the second relay. This design ensures that the second relay avoids being subjected to arcing impacts. Therefore, when the final protection disconnection action is required, the second relay, with its normal mechanical contacts and virtually undamaged physical state, can reliably cut off the current. This timing control strategy separates "high-frequency daily actions" from "low-frequency safety actions," ensuring the absolute reliability of the backup protection device at critical moments, and is a key means of improving the system's functional safety level.

[0048] Furthermore, upon receiving the operating command of the electric heater, controlling the first relay and the second relay to close includes: upon receiving the operating command of the electric heater, first controlling the second relay to close, and after the second relay has been closed for a second preset time period, controlling the first relay to close.

[0049] The second preset time period can be set to 1 second.

[0050] In this embodiment, a staggered control strategy is also employed during the closing phase to protect the integrity of the second relay's contacts and prevent arcing during daily operation. This avoids the possibility of arcing due to contact asynchrony or load impact if both relays close simultaneously. This solution specifies that the second relay is closed first (at which point the circuit is not yet energized and there is no current). After a second preset time period to ensure its mechanical position is stable, the first relay is then closed. Since no current flows through the circuit at the moment of closure of the second relay, no arc discharge occurs between its contacts, thus avoiding the risk of oxidation, ablation, or welding of the contact materials. This arc-free closing mechanism ensures that the second relay always maintains optimal contact resistance and insulation performance, extending its electrical life. Combined with the above-described disconnection logic, a complete low-stress protection strategy is formed, ensuring that the second relay, as a core component of the electronic thermal fuse, maintains high reliability throughout the entire product lifecycle.

[0051] Furthermore, the above method also includes: upon receiving a stop-work command from the electric heater, controlling the first relay to open and controlling the second relay to remain closed; after a third preset time period, acquiring the duct temperature change rate; if the duct temperature change rate is greater than or equal to a set change rate value, determining that the first relay is faulty, controlling the second relay to open, and generating first relay fault information; if the duct temperature change rate is less than the set change rate value, determining that the first relay is normal, and controlling the second relay to remain closed.

[0052] In this embodiment, a self-diagnostic function is introduced after operation, enabling real-time monitoring and fault warning of the health status of the first relay, thus improving the maintainability and safety of the system. Upon receiving a stop command, the first relay should disconnect. If its contacts stick together at this time, the electric heater will continue to heat up, posing a fire hazard. This solution monitors the temperature change rate of the duct after disconnection and uses the principle of thermal inertia to determine whether the disconnection is effective: if the temperature drops sharply, the disconnection is successful; if the temperature rises or falls slowly, it is inferred that the first relay may be stuck. Once an anomaly is detected, the system immediately forces the disconnection of the second relay as a backup protection path and generates fault information for the first relay. This closed-loop diagnostic mechanism not only provides a last line of physical defense when the first relay fails, but also clearly informs users or maintenance personnel which specific component (the first relay) has failed, reducing the difficulty of troubleshooting. This significantly reduces the probability of safety accidents caused by hidden faults in mechanical components.

[0053] Specifically, after generating fault information, the above includes: upon receiving a reset command from the above-mentioned electric heating protection circuit, determining that the fault has been cleared, and controlling the above-mentioned first relay and the above-mentioned second relay to resume normal operation.

[0054] This embodiment provides a convenient manual reset mechanism, solving the high cost problem of needing to replace components after the traditional thermal fuse trips, improving user experience and reducing after-sales maintenance costs. After triggering heating protection, the system enters a locked state to prevent automatic restart. When the user or maintenance personnel troubleshoot the problem (e.g., clear blockages), they can send a reset command via remote control or buttons. The system then confirms the fault has been cleared and restores the relay to normal operation. This software-defined reset function gives the electronic thermal fuse a resettable characteristic while retaining the safety logic of non-self-resetting (i.e., it will never restart before the fault is cleared). This not only eliminates the user's anxiety about waiting for parts to be replaced due to machine failure but also avoids the labor and material costs associated with disassembling the machine, finding parts, and replacing them with new components, as required by traditional thermal fuses. This design balances the stringent requirements of safety regulations with the convenience of commercial applications, achieving the goal of low cost and high system security.

[0055] To enable those skilled in the art to better understand the technical solution of this application, the implementation process of the air conditioner electric heating protection method of this application will be described in detail below with reference to specific embodiments.

[0056] This embodiment provides an electronic non-self-resetting thermal fuse, mainly composed of a main control module, a temperature acquisition unit, an actuator, and a human-machine interface. The main control module is the core controller, employing a microcontroller (MCU) that has passed the IEC 61508 functional safety level assessment. This MCU integrates a secure watchdog circuit, a self-diagnostic program, and an encrypted logic storage area to ensure that the control logic does not experience logical errors under any operating condition. The MCU is powered by a safety isolation transformer, and its output is connected to two high-performance relays. These relays have a rated electrical life of no less than 100,000 closing / opening operations and can effectively resist arc erosion and prevent contact welding. Relay A (the first relay) is defined as a general-purpose control relay, and relay B (the second relay) is defined as a high-reliability thermal protector disconnect switch, used to perform the disconnecting function of the electronic thermal fuse.

[0057] The temperature acquisition unit includes at least one high-precision thermistor (NTC) that meets the requirements of UL60730-2-101 or IEC60730-2-23 standards. In practical applications, this thermistor is installed inside the air outlet of the duct or in the upstream duct to detect the air temperature flowing through the heating area in real time. The thermistor is connected to the MCU's ADC (Analog-to-Digital Converter) pin via a voltage divider circuit to convert the analog temperature signal into a digital signal for MCU processing.

[0058] The actuator, namely the aforementioned relay, is connected in series on the main power supply line of the heater circuit. When the MCU issues a disconnect command, the relay contacts physically separate, completely cutting off the power supply to the heater.

[0059] By detecting the temperature of the air outlet or air duct through the air duct temperature sensor (thermistors can be selected), it can be determined that there is an abnormal situation of air inlet blockage. Based on the specific temperature value and the selected function, it can enter the "single temperature limiter protection function", "single non-self-resetting thermal circuit breaker protection function" or "composite thermal protector protection function" to make different fault handling modes and improve product safety.

[0060] You can choose one of the three function modes depending on the usage:

[0061] 1) Single temperature limiter protection function: When the outlet temperature reaches the temperature limiter's operating temperature, it will protect the system and enter the "electronic temperature limiter protection mode".

[0062] 2) Single non-self-resetting thermal circuit breaker protection function: It does not provide protection when the outlet temperature reaches the operating temperature of the temperature limiter, and only enters the "electronic thermal circuit breaker protection mode" when the outlet temperature reaches the thermal fuse protection temperature.

[0063] 3) Composite thermal protector protection function: It has the functions of a temperature limiter and a non-self-resetting thermal circuit breaker. When the outlet temperature reaches the operating temperature of the electronic temperature limiter, it will protect the device and enter the "electronic temperature limiter protection mode"; when the outlet temperature reaches the protection temperature of the electronic thermal fuse, it will enter the "electronic thermal fuse protection mode".

[0064] This embodiment relates to a specific method for protecting the electric heating of an air conditioner, such as... Figure 4 As shown, it specifically includes the following:

[0065] After detecting that the system is powered on, the single non-self-resetting thermal circuit breaker protection function is selected, the MCU initializes its internal parameters, starts the temperature sampling cycle, and reads the outlet temperature.

[0066] 1. The MCU reads the resistance value of the thermistor, looks up the value in a table to convert it into the current duct temperature value T_c, and calculates the temperature change rate ΔT / Δt per unit time. Simultaneously, the system records the historical highest temperature T_max.

[0067] Set the electronic thermal fuse protection temperature T_r, T_r=T_x+T0, where T_x is the highest temperature obtained by the thermistor under abnormal testing (blocking the air inlet and outlet) under normal temperature limiter conditions, and T0 is used to distinguish the range compensation temperature given by T_r and T_x, which is generally a value of 1 to 30℃.

[0068] 2. The MCU judges the data according to the preset algorithm model:

[0069] If T_c is detected to be gradually increasing, but T_x≤T_c<T_r, the program will not enter the "electronic temperature limiter protection mode". At this time, the range of ΔT / Δt will be judged. When ΔT / Δt is in a low range (e.g., 1℃ / s < ΔT / Δt < 5℃ / s) and has not reached the emergency cut-off threshold, it usually means that the airflow is obstructed but has not completely stopped. Heat is accumulating but the cooling medium is still flowing, and there is no need to enter the protection mode in advance. When ΔT / Δt is in a high range (e.g., ΔT / Δt ≥ 5℃ / s) and reaches the emergency cut-off threshold, it usually means that the airflow is severely obstructed and the temperature is rising sharply. It is necessary to enter the protection mode in advance. At this time, the electronic thermal fuse protection mode will be entered.

[0070] If a gradual increase in T_c is detected, and T_c≥T_r, the protection mode is triggered, and the electronic thermal fuse protection mode is entered.

[0071] 3. Perform protective actions:

[0072] Entering "Thermal Fuse Protection Mode": When a severe blockage at the air inlet or outlet is detected, the MCU immediately drives relay A to disconnect, and relay B disconnects 1 second later, locking the relays in the disconnected state. Simultaneously, the display shows a fault code. The relays remain disconnected regardless of temperature changes. After maintenance personnel inspect the machine and remove the blockage, they can manually reset the relays (using a remote control, buttons, or remote network operation). At this point, the thermal fuse protection mode exits, and the relays return to normal operation. This mode simulates the function of a traditional thermal fuse, preventing automatic reset and ensuring absolute heat source cutoff in dangerous situations to prevent fires. Furthermore, after troubleshooting, maintenance personnel can quickly restore the electronic thermal fuse to normal operation manually without replacing components, avoiding the complex operation and replacement costs associated with traditional thermal fuses, which require disassembling the fuse on the machine's electric heater and replacing it with a new one.

[0073] Entering "Temperature Limiter Protection Mode": When the blockage at the air inlet and outlet is determined to be minor, relay A disconnects, and relay B disconnects 1 second later, simultaneously displaying a fault signal. As T_c gradually decreases to the recovery temperature, the electric heating power supply is restored. At this time, relay B connects, and relay A connects 1 second later. This mode is similar to a traditional temperature limiter, aiming to control the temperature within a safe range while maintaining some functions of the equipment and reminding the user to check for filter blockage. Because the electric heating power supply circuit is open when relay B is connected, no electric arc is generated between the contacts of relay B, and the action of relay B is mechanical, ensuring the reliability of relay B's operation.

[0074] To prevent the relay from failing to disconnect due to an MCU crash, an independent hardware safety circuit is set up inside the MCU. Once the watchdog timeout occurs or an internal logic error is detected in the MCU, the hardware circuit will forcibly pull down the relay drive signal, putting the relay into a normally open (power-off disconnect) safe state.

[0075] In addition, the relay selection has undergone more than 100,000 load tests. The electric heating power supply adopts dual relay control, and the relays adopt staggered delay control measures to ensure that after experiencing frequent operation of the "temperature limiter protection mode" multiple times, one of the relays can still maintain reliable insulation performance and conduction capability, avoiding failure to operate or sticking due to contact oxidation.

[0076] The dual-relay control mode is as follows: The dual relays are relay A and relay B, where relay A is a general control relay, and relay B is defined as a high-reliability thermal protector disconnect switch. Figure 5As shown, when the controller needs to power on the electric heater, relay B is activated first. Since relay A is not energized at this time, no current flows through the power supply circuit. The activation of relay B is a mechanical action, and no arc occurs between the contacts of relay B. One second later, relay A is activated, generating an arc between its contacts at the instant of activation, completing one electrical connection operation. When the indoor temperature reaches the point where the electric heater needs to be disconnected, relay A is deactivated, generating an arc between its contacts at the instant of deactivation, completing one electrical disconnection operation. Afterward, relay B remains activated. Relay B will not activate due to changes in the indoor ambient temperature during heating operation, ensuring its definition as an electronic thermal fuse disconnector, guaranteeing high reliability even in abnormal situations. For relays with an electrical life of 100,000 cycles, the mechanical life can generally reach 1 million cycles. The above control measures ensure high reliability for relay B, guaranteeing that even if the contacts of relay A stick together, relay B can still reliably disconnect the power supply circuit of the electric heater.

[0077] To ensure that during heating operation, relay A does not become stuck, preventing the electric heater from disconnecting, such as... Figure 5 As shown, after relay A disconnects, the system detects the air outlet temperature T_c and its temperature change ΔT after t1 seconds. If the temperature change ΔT is negative and its absolute value is greater than 2, the disconnection is considered normal. If the temperature change ΔT is positive and its absolute value is ≥1, the relay is considered stuck. At this time, relay B activates, disconnects the electric heating, and displays fault information. If the temperature change -2≤ΔT<1, the system detects the air outlet temperature T_c and its temperature change ΔT after t2 seconds. If the temperature change ΔT is negative, the disconnection is considered normal. If ΔT≥0, the relay is considered stuck. At this time, relay B activates, disconnects the electric heating, and displays fault information.

[0078] Through the above embodiments, the solution of this application realizes intelligent and hierarchical management of the overheating risk of heating equipment, which not only improves the user experience, but also greatly enhances the inherent safety level of the product.

[0079] This application also provides an air conditioner electric heating protection device. It should be noted that this air conditioner electric heating protection device can be used to execute the air conditioner electric heating protection method provided in this application. This device is used to implement the above embodiments and preferred embodiments; details already described will not be repeated. As used below, the term "module" can refer to a combination of software and / or hardware that performs a predetermined function. Although the device described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0080] The following describes the air conditioning electric heating protection device provided in the embodiments of this application.

[0081] The above-mentioned device is applied to the controller of the electric heating protection circuit. The electric heating protection circuit also includes a duct temperature sensor, and a power supply, a first relay, a thermal fuse, an electric heater, a temperature limiter, and a second relay connected in sequence. The duct temperature sensor, the first relay, and the second relay are respectively electrically connected to the controller. Figure 6 This is a schematic diagram of an air conditioner electric heating protection device according to an embodiment of this application, such as... Figure 6 As shown, the device includes:

[0082] The first control unit 61 is used to control the first relay and the second relay to close when it receives the working command of the electric heater.

[0083] The acquisition unit 62 is used to acquire the duct temperature, the fuse temperature and the temperature limit temperature, wherein the duct temperature is the temperature collected by the duct temperature sensor, the fuse temperature is the temperature at which the thermal fuse melts, the temperature limit temperature is the temperature limit of the temperature limiter, and the fuse temperature is greater than the temperature limit temperature.

[0084] The second control unit 63 is used to control the operation of the first relay and the second relay according to the duct temperature, the fuse temperature and the temperature limit, so as to realize the air conditioning electric heating protection before the thermal fuse melts.

[0085] In this embodiment, the first control unit is used to control the closure of the first and second relays when it receives the working command of the electric heater; the acquisition unit is used to acquire the duct temperature, the fuse temperature, and the temperature limit temperature, wherein the duct temperature is the temperature collected by the duct temperature sensor, the fuse temperature is the temperature at which the thermal fuse melts, and the temperature limit temperature is the temperature limit set by the temperature limiter, and the fuse temperature is greater than the temperature limit temperature; the second control unit is used to control the operation of the first and second relays according to the duct temperature, the fuse temperature, and the temperature limit temperature, so as to achieve air conditioning electric heating protection before the thermal fuse melts. An air conditioning electric heating protection scheme based on multiple temperature thresholds and dual-relay collaborative control is constructed, improving the system's response speed and protection reliability under abnormal operating conditions. The thermal fuse is a disposable mechanical device that needs to be manually replaced after melting, resulting in high maintenance costs; however, this scheme uses a duct temperature sensor for real-time monitoring, combined with preset fuse and temperature limit temperatures, to intervene in advance through a control strategy before the physical thermal fuse actually operates. Specifically, this solution can control the on / off state of the first and second relays before the thermal fuse melts due to high temperature, thereby cutting off the heating circuit. This electronic pre-protection mechanism not only solves the problems of traditional thermal fuse protection being delayed and unable to meet backup test requirements, but also achieves the definability of the protection temperature. Furthermore, through the series control of the two relays, it ensures that the power supply is completely cut off in emergencies, avoiding protection failure caused by a single relay malfunction. This greatly improves the safety level of the entire unit under extreme conditions such as blocked air outlets, while reducing after-sales maintenance costs. Thus, it solves the problem of existing electric heating protection schemes relying on the physical characteristics of thermal fuses for melting protection, resulting in long response times and untimely protection.

[0086] As an optional solution, the second control unit includes a first determining module, a first controlling module, and a second controlling module. The first determining module is used to determine the temperature change rate of the air duct temperature when the detected air duct temperature is greater than or equal to the temperature limit temperature and less than the melting temperature. The first controlling module is used to control the first relay and the second relay to disconnect when the temperature change rate is greater than or equal to the change rate threshold, and generate fault information, wherein the fault information is used to remind the user that the air inlet and outlet of the air conditioner are blocked. The second controlling module is used to control the first relay and the second relay to remain closed when the temperature change rate is less than the change rate threshold.

[0087] In one alternative, the second control unit further includes a third control module, which controls the first relay to disconnect from the second relay and generates fault information when the temperature of the air duct is detected to be greater than or equal to the melting temperature. The fault information is used to remind the user that the air inlet and outlet of the air conditioner are blocked.

[0088] In one alternative, the second control unit further includes a fourth control module, which is used to first control the first relay to disconnect, and then control the second relay to disconnect after the first relay has been disconnected for a first preset time period.

[0089] In one alternative, the first control unit includes a fifth control module, which, upon receiving the operating command of the electric heater, first controls the second relay to close, and then controls the first relay to close after the second relay has been closed for a second preset time period.

[0090] In an optional embodiment, the device further includes a third control unit, a fourth control unit, and a fifth control unit; the third control unit is used to control the first relay to open and control the second relay to remain closed when receiving a stop operation command from the electric heater; the fourth control unit is used to acquire the duct temperature change rate after a third preset time period, and if the duct temperature change rate is greater than or equal to a set change rate value, determine that the first relay is faulty, control the second relay to open, and generate first relay fault information; the fifth control unit is used to determine that the first relay is normal and control the second relay to remain closed if the duct temperature change rate is less than the set change rate value.

[0091] In one alternative, the second control unit further includes a second determining module, which, after generating fault information and receiving a reset command from the aforementioned electric heating protection circuit, determines that the fault has been cleared and controls the first relay and the second relay to return to normal operation.

[0092] The aforementioned air conditioner electric heating protection device includes a processor and a memory. The first control unit, acquisition unit, second control unit, etc., are all stored as program units in the memory, and the processor executes the program units stored in the memory to achieve the corresponding functions. All of the above modules are located in the same processor; alternatively, the various modules may be located in different processors in any combination.

[0093] The processor contains a kernel, which retrieves the corresponding program unit from memory. One or more kernels can be configured. By adjusting kernel parameters, the problem of existing electric heating protection schemes relying on the physical characteristics of thermal fuses for protection, resulting in long response times and untimely protection, can be addressed.

[0094] The memory may include non-permanent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip.

[0095] This invention provides a computer-readable storage medium including a stored program, wherein, when the program is executed, it controls the device containing the computer-readable storage medium to perform the air conditioner electric heating protection method.

[0096] Specifically, the protection methods for air conditioner electric heating include:

[0097] Step S201: Upon receiving the operating command of the electric heater, control the first relay and the second relay to close.

[0098] Step S202: Obtain the duct temperature, the fuse temperature, and the temperature limit temperature, wherein the duct temperature is the temperature collected by the duct temperature sensor, the fuse temperature is the temperature at which the thermal fuse melts, the temperature limit temperature is the temperature limit of the temperature limiter, and the fuse temperature is greater than the temperature limit temperature.

[0099] Step S203: Control the operation of the first relay and the second relay according to the above-mentioned duct temperature, the above-mentioned fuse temperature and the above-mentioned temperature limit temperature, so as to realize the air conditioner electric heating protection before the above-mentioned thermal fuse melts.

[0100] This invention provides a processor for running a program, wherein the program executes the air conditioner electric heating protection method.

[0101] Specifically, the protection methods for air conditioner electric heating include:

[0102] Step S201: Upon receiving the operating command of the electric heater, control the first relay and the second relay to close.

[0103] Step S202: Obtain the duct temperature, the fuse temperature, and the temperature limit temperature, wherein the duct temperature is the temperature collected by the duct temperature sensor, the fuse temperature is the temperature at which the thermal fuse melts, the temperature limit temperature is the temperature limit of the temperature limiter, and the fuse temperature is greater than the temperature limit temperature.

[0104] Step S203: Control the operation of the first relay and the second relay according to the above-mentioned duct temperature, the above-mentioned fuse temperature and the above-mentioned temperature limit temperature, so as to realize the air conditioner electric heating protection before the above-mentioned thermal fuse melts.

[0105] This invention provides an electronic device, which includes a processor, a memory, and a program stored in the memory and executable on the processor. When the processor executes the program, it performs at least the following steps:

[0106] Step S201: Upon receiving the operating command of the electric heater, control the first relay and the second relay to close.

[0107] Step S202: Obtain the duct temperature, the fuse temperature, and the temperature limit temperature, wherein the duct temperature is the temperature collected by the duct temperature sensor, the fuse temperature is the temperature at which the thermal fuse melts, the temperature limit temperature is the temperature limit of the temperature limiter, and the fuse temperature is greater than the temperature limit temperature.

[0108] Step S203: Control the operation of the first relay and the second relay according to the above-mentioned duct temperature, the above-mentioned fuse temperature and the above-mentioned temperature limit temperature, so as to realize the air conditioner electric heating protection before the above-mentioned thermal fuse melts.

[0109] The devices mentioned in this article can be servers, PCs, tablets, mobile phones, etc.

[0110] This application also provides a computer program product, which, when executed on a data processing device, is suitable for executing an initialization program having at least the following method steps:

[0111] Step S201: Upon receiving the operating command of the electric heater, control the first relay and the second relay to close.

[0112] Step S202: Obtain the duct temperature, the fuse temperature, and the temperature limit temperature, wherein the duct temperature is the temperature collected by the duct temperature sensor, the fuse temperature is the temperature at which the thermal fuse melts, the temperature limit temperature is the temperature limit of the temperature limiter, and the fuse temperature is greater than the temperature limit temperature.

[0113] Step S203: Control the operation of the first relay and the second relay according to the above-mentioned duct temperature, the above-mentioned fuse temperature and the above-mentioned temperature limit temperature, so as to realize the air conditioner electric heating protection before the above-mentioned thermal fuse melts.

[0114] It is obvious to those skilled in the art that the modules or steps of the present invention described above can be implemented using general-purpose computing devices. They can be centralized on a single computing device or distributed across a network of multiple computing devices. They can be implemented using computer-executable program code, and thus can be stored in a storage device for execution by a computing device. In some cases, the steps shown or described can be performed in a different order than those described herein, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Thus, the present invention is not limited to any particular combination of hardware and software.

[0115] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0116] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0117] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0118] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0119] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0120] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0121] Computer-readable media include both permanent and non-permanent, removable and non-removable media that can store information by any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0122] 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 specification.

[0123] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0124] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for protecting the electric heating of an air conditioner, characterized in that, The method is applied to a controller for an electric heating protection circuit. The electric heating protection circuit further includes a duct temperature sensor, and a power supply, a first relay, a thermal fuse, an electric heater, a temperature limiter, and a second relay connected in sequence. The duct temperature sensor, the first relay, and the second relay are each electrically connected to the controller. The method includes: Upon receiving the operating command of the electric heater, the first relay and the second relay are controlled to close. The duct temperature, the fuse temperature, and the temperature limit temperature are obtained, wherein the duct temperature is the temperature collected by the duct temperature sensor, the fuse temperature is the temperature at which the thermal fuse melts, the temperature limit temperature is the temperature limit set by the temperature limiter, and the fuse temperature is greater than the temperature limit temperature. The first and second relays are controlled to operate based on the air duct temperature, the fuse temperature, and the temperature limit temperature, so as to achieve air conditioning electric heating protection before the thermal fuse melts.

2. The method according to claim 1, characterized in that, Controlling the operation of the first and second relays based on the duct temperature, the fuse temperature, and the temperature limit temperature includes: If the temperature of the air duct is detected to be greater than or equal to the temperature limit temperature and less than the melting temperature, the temperature change rate of the air duct temperature is determined. When the temperature change rate is greater than or equal to the change rate threshold, the first relay is controlled to disconnect from the second relay, and fault information is generated, wherein the fault information is used to remind the user that the air inlet and outlet of the air conditioner are blocked; When the rate of temperature change is less than the rate of change threshold, the first relay and the second relay are controlled to remain in a closed state.

3. The method according to claim 1, characterized in that, Controlling the operation of the first and second relays based on the duct temperature, the fuse temperature, and the temperature limit temperature includes: If the temperature of the air duct is detected to be greater than or equal to the melting temperature, the first relay and the second relay are disconnected, and fault information is generated. The fault information is used to remind the user that the air inlet and outlet of the air conditioner are blocked.

4. The method according to claim 2 or 3, characterized in that, Controlling the first relay to disconnect from the second relay includes: First, control the first relay to disconnect, and after the first relay has been disconnected for a first preset time period, control the second relay to disconnect.

5. The method according to claim 1, characterized in that, Upon receiving the operating command of the electric heater, controlling the first relay and the second relay to close includes: Upon receiving the operating command of the electric heater, the system first controls the second relay to close, and after the second relay has been closed for a second preset time period, it controls the first relay to close.

6. The method according to claim 1, characterized in that, The method further includes: Upon receiving a stop command from the electric heater, the system controls the first relay to disconnect and the second relay to remain closed. After a third preset time period, the duct temperature change rate is obtained. If the duct temperature change rate is greater than or equal to the change rate set value, the first relay is determined to be faulty, the second relay is controlled to disconnect, and the first relay fault information is generated. If the rate of change of the air duct temperature is less than the set value of the rate of change, the first relay is determined to be normal, and the second relay is controlled to remain closed.

7. The method according to claim 2, characterized in that, After generating the fault information, the following steps are included: Upon receiving a reset command from the electric heating protection circuit, the fault is determined to be cleared, and the first and second relays are controlled to resume normal operation.

8. An air conditioner electric heating protection device, characterized in that, The device is applied to the controller of an electric heating protection circuit. The electric heating protection circuit further includes a duct temperature sensor, and a power supply, a first relay, a thermal fuse, an electric heater, a temperature limiter, and a second relay connected in sequence. The duct temperature sensor, the first relay, and the second relay are respectively electrically connected to the controller. The device includes: The first control unit is used to control the first relay and the second relay to close when it receives the working command of the electric heater; The acquisition unit is used to acquire the duct temperature, the fuse temperature, and the temperature limit temperature, wherein the duct temperature is the temperature collected by the duct temperature sensor, the fuse temperature is the temperature at which the thermal fuse melts, the temperature limit temperature is the temperature limit of the temperature limiter, and the fuse temperature is greater than the temperature limit temperature. The second control unit is used to control the operation of the first relay and the second relay according to the air duct temperature, the fuse temperature and the temperature limit temperature, so as to realize the air conditioner electric heating protection before the thermal fuse melts.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored program, wherein, when the program is executed, it controls the device containing the computer-readable storage medium to perform the air conditioning electric heating protection method according to any one of claims 1 to 7.

10. An air conditioner, characterized in that, include: One or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs including methods for performing the air conditioning electric heating protection method according to any one of claims 1 to 7.

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