Control method and system for an electric heating tube

Abstract

The present disclosure provides a control method and system of an electric heating tube, wherein the control method of the electric heating tube comprises: determining a control mode strategy based on a current core temperature, a target temperature and a preset error of the electric heating tube; obtaining a preset number of different sub-period parameters corresponding to the control mode strategy; and segmenting the electric heating tube for heating according to the sub-period parameters and a preset sub-period parameter execution sequence. The present disclosure sets different sub-period parameters through multiple PWM periods to achieve different heating strategies in different control mode strategies, such as providing concentrated energy in the fast heating mode strategy and achieving fine adjustment in the steady-state maintenance mode strategy, thereby reducing energy waste and shortening the time for the current core temperature of the electric heating tube to reach the target temperature. The present disclosure avoids the severe cold and hot cycle under the traditional on-off control, and the staggered mild heating under the multiple PWM, especially the approaching balanced mode strategy, reduces the thermal stress impact, thereby prolonging the service life of the electric heating tube.

Description

Technical Field

[0001] This disclosure relates to the field of heating equipment technology, and in particular to a control method and system for an electric heating tube. Background Technology

[0002] Electric heating elements are common components that convert electrical energy into heat energy and are widely used in household appliances, industrial heating equipment, and other fields. Traditional control methods for electric heating elements are mainly divided into two types: one is simple on / off control (Bang-Bang control), and the other is conventional pulse width modulation (PWM) control.

[0003] In the on / off control mode, the heating element is turned on at full power or completely turned off within a set cycle. Although this method is simple, it leads to large temperature fluctuations in the heated medium or the heating element itself, high thermal inertia, high energy consumption, and frequent thermal shocks will reduce the lifespan of the heating element.

[0004] Conventional PWM control adjusts the average power by regulating the duty cycle of the energizing time within a fixed period. Although it is smoother than on-off control, it still has the following shortcomings: First, at low power output, a single long-cycle shutdown can easily lead to local overcooling of the heating element and uneven heat distribution. Second, it does not consider the real-time state of the heating element itself and the surrounding thermal field, making it difficult to achieve dynamic optimal control. Third, there is still room for improvement in heating efficiency, especially in the fast response and steady-state maintenance phases. Summary of the Invention

[0005] The technical problem to be solved by this disclosure is to overcome the defects of existing electric heating tube control methods, such as low heating efficiency, uneven heat field, large temperature fluctuation and impact on heating tube life, and to provide a control method and system for electric heating tubes.

[0006] This disclosure solves the above-mentioned technical problems through the following technical solution:

[0007] This disclosure provides a method for controlling an electric heating element, the method comprising:

[0008] Based on the current core temperature, target temperature, and preset error of the electric heating element, a control mode strategy is determined.

[0009] Obtain a preset number of different sub-time period parameters corresponding to the control mode strategy;

[0010] The control mode strategy includes multiple PWM cycles, and the total duration of all sub-time periods is the duration of a single PWM cycle. The sub-time parameters include at least the sub-time duration and the sub-time duty cycle. The sum of the first ratios is the same as the average duty cycle of the reference power. The first ratio is the ratio of the first product to the duration of a single PWM cycle, and the first product is the product of the sub-time duration and the sub-time duty cycle.

[0011] The electric heating tube is heated in segments according to the execution order of the sub-time period parameters and the preset sub-time period parameters.

[0012] Preferably, the step of determining the control mode strategy based on the current core temperature, target temperature, and preset error of the electric heating element includes:

[0013] In response to the current core temperature being less than a first difference, a rapid heating mode strategy is determined; wherein, the first difference is the difference between the target temperature, a preset allowable error, and a preset heating lag threshold; the rapid heating mode strategy corresponds to a first preset number of different sub-time period parameters;

[0014] Preferably, the step of determining the control mode strategy based on the current core temperature, target temperature, and preset error of the electric heating element further includes:

[0015] In response to the current core temperature being less than or equal to the target temperature, and the current core temperature being greater than or equal to the first difference, an equilibrium-approaching mode strategy is determined.

[0016] The approach-equilibrium mode strategy corresponds to a second preset number of different sub-time period parameters; the second preset number is greater than the first preset number.

[0017] Preferably, the step of determining the control mode strategy based on the current core temperature, target temperature, and preset error of the electric heating element further includes:

[0018] In response to the current core temperature being greater than the target temperature and the preset allowable error being greater than the second difference, a steady-state maintenance mode strategy is determined.

[0019] Wherein, the second difference is the difference between the current core temperature and the target temperature, and the steady-state maintenance mode strategy corresponds to a third preset number of different sub-time period parameters; the third preset number is greater than the second preset number.

[0020] Preferably, the reference power is determined based on the difference between the current core temperature and the target temperature using a PID algorithm or a fuzzy control algorithm.

[0021] Preferably, the duty cycle of the sub-time period corresponding to the approaching equilibrium mode strategy is determined based on the thermal field equilibrium factor and the weighting function;

[0022] The thermal field equalization factor is positively correlated with the maximum temperature difference, which is the maximum temperature difference between the current core temperature and the current axial temperature of the electric heating tube, or the maximum temperature difference between the current core temperature of the electric heating tube and the current temperature of the surrounding medium.

[0023] This disclosure also provides a control system for an electric heating element, the control system comprising:

[0024] The determination module is used to determine the control mode strategy based on the current core temperature, target temperature and preset error of the electric heating tube;

[0025] The acquisition module is used to acquire a preset number of different sub-time period parameters corresponding to the control mode strategy;

[0026] The control mode strategy includes multiple PWM cycles, and the total duration of all sub-time periods is the duration of a single PWM cycle. The sub-time parameters include at least the sub-time duration and the sub-time duty cycle. The sum of the first ratios is the same as the average duty cycle of the reference power. The first ratio is the ratio of the first product to the duration of a single PWM cycle, and the first product is the product of the sub-time duration and the sub-time duty cycle.

[0027] The heating module is used to heat the electric heating tube in segments according to the execution order of the sub-time period parameters and the preset sub-time period parameters.

[0028] This disclosure also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and used to run on the processor, wherein the processor executes the computer program to implement the above-described control method for an electric heating tube.

[0029] This disclosure also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-described control method for an electric heating tube.

[0030] This disclosure also provides a computer program product, including a computer program that, when executed by a processor, implements the control method for the electric heating tube as described above.

[0031] Based on common knowledge in the field, the above-mentioned preferred conditions can be combined arbitrarily to obtain various preferred embodiments of this disclosure.

[0032] The positive and progressive effects of this disclosure are as follows:

[0033] This disclosure utilizes multi-segment PWM (Pulse Width Modulation) cycles to set different sub-time parameters, enabling different heating strategies under different control modes. For example, the rapid heating mode provides concentrated energy, while the steady-state maintenance mode allows for fine-tuning, reducing energy waste and shortening the time it takes for the electric heating element's core temperature to reach the target temperature. This avoids the drastic heating and cooling cycles inherent in traditional on-off control. The interleaved, gentle heating under multi-segment PWM, especially the near-equilibrium mode strategy, reduces thermal stress impact, thereby extending the lifespan of the electric heating element. Attached Figure Description

[0034] Figure 1 A flowchart illustrating a control method for an electric heating element provided as an exemplary embodiment of this disclosure;

[0035] Figure 2 A schematic diagram of the structure of a control system for an electric heating tube provided as an exemplary embodiment of this disclosure;

[0036] Figure 3 This is a schematic diagram of the structure of an electronic device provided as an exemplary embodiment of the present disclosure. Detailed Implementation

[0037] The present disclosure is further illustrated below by way of embodiments, but the present disclosure is not limited to the scope of the embodiments described herein.

[0038] The prefixes such as "first" and "second" used in this disclosure are merely for distinguishing different descriptive objects and do not limit the position, order, priority, quantity, or content of the described objects. The use of ordinal numbers and other prefixes used to distinguish descriptive objects in this disclosure does not constitute a limitation on the described objects. The description of the described objects is given in the claims or the context of the embodiments, and should not be construed as an unnecessary limitation. Furthermore, in the description of this embodiment, unless otherwise stated, "multiple" means two or more.

[0039] Example 1

[0040] An exemplary embodiment of this disclosure improves the heating efficiency and heat uniformity of the heating field of an electric heating tube by using a control method based on multi-segment PWM and thermal field equalization, thereby extending the life of the electric heating tube.

[0041] Figure 1 A flowchart of a control method for an electric heating element provided as an exemplary embodiment of this disclosure is shown below. Figure 1 As shown, the control method for the electric heating element includes:

[0042] S1. Determine the control mode strategy based on the current core temperature, target temperature, and preset error of the electric heating tube.

[0043] The current core temperature of the electric heating element is monitored in real time by at least one main temperature sensor.

[0044] S2. Obtain the parameters of different sub-time periods corresponding to the preset number of control modality strategies.

[0045] The control mode strategy includes multiple PWM cycles, with the total duration of all sub-time periods equal to the duration of a single PWM cycle. Sub-time parameters include at least the sub-time period duration and the sub-time period duty cycle. The sum of the first ratios is the same as the average duty cycle of the reference power. The first ratio is the ratio of the first product to the duration of a single PWM cycle, where the first product is the product of the sub-time period duration and the sub-time period duty cycle.

[0046] In an alternative implementation, the reference power is determined based on the difference between the current core temperature and the target temperature using a PID algorithm (proportional-integral-derivative control algorithm) or a fuzzy control algorithm.

[0047] Taking the PID algorithm as an example, the reference power is determined by the following formula:

[0048] ;

[0049] ;

[0050] Where t represents the current time, Preq represents the reference power, T_target represents the target temperature, T_core represents the current core temperature, e(t) represents the temperature deviation at the current time, and K... p Used to characterize the proportionality coefficient, K i Used to characterize integral coefficients, K d Used to characterize the differential coefficient, P feedforward Used to characterize feedforward compensation, for example, if system voltage fluctuations cause power changes, or if the system has basic heat loss, the reference power can be directly adjusted through feedforward compensation without having to wait for temperature deviations to occur before PID correction.

[0051] S3. Perform segmented heating of the electric heating tube according to the sub-time period parameters and the preset sub-time period parameters.

[0052] It should be noted that the target temperature, preset error, and preset sub-time period parameters can be set according to the actual situation.

[0053] This embodiment uses multi-segment PWM (Pulse Width Modulation) cycles to set different sub-time parameters, implementing different heating strategies in different control modes. For example, the rapid heating mode provides concentrated energy, while the steady-state maintenance mode enables fine-tuning, reducing energy waste and shortening the time it takes for the electric heating element's current core temperature to reach the target temperature. It avoids the drastic heating and cooling cycles of traditional on / off control. The interleaved, gentle heating under multi-segment PWM, especially the near-equilibrium mode strategy, reduces thermal stress impact, thereby extending the lifespan of the electric heating element.

[0054] In an optional implementation, step S1 includes:

[0055] If the current core temperature is less than a first difference value, a rapid heating mode strategy is determined. The first difference value is the difference between the target temperature, a preset allowable error, and a preset heating hysteresis threshold. The rapid heating mode strategy corresponds to a first preset number of different sub-time period parameters.

[0056] It should be noted that the preset allowable error, preset heating lag threshold, and first preset number can be set according to the actual situation.

[0057] In an optional implementation, step S1 further includes:

[0058] If the current core temperature is less than or equal to the target temperature and the current core temperature is greater than or equal to the first difference, then the approaching equilibrium mode strategy is determined.

[0059] The approach-equilibrium mode strategy corresponds to a second preset number of parameters for different sub-time periods. The second preset number is greater than the first preset number.

[0060] It should be noted that the second preset number can be set according to the actual situation.

[0061] In one optional implementation, the duty cycle of the sub-period corresponding to the equilibrium mode strategy is determined based on the thermal field equilibrium factor and the weighting function.

[0062] Among them, the thermal field equilibrium factor is positively correlated with the maximum temperature difference, which is the maximum temperature difference between the current core temperature and the current axial temperature of the electric heating tube, or the current core temperature of the electric heating tube and the current temperature of the surrounding medium.

[0063] The current axial temperature of the electric heating element and the current temperature of the medium surrounding the electric heating element are monitored by at least two auxiliary temperature sensors.

[0064] In an optional implementation, step S1 further includes:

[0065] When the current core temperature is greater than the target temperature and the preset allowable error is greater than the second difference, determine the steady-state maintenance mode strategy.

[0066] Wherein, the second difference is the difference between the current core temperature and the target temperature, and the steady-state maintenance mode strategy corresponds to the third preset number of different sub-period parameters. The third preset number is greater than the second preset number.

[0067] It should be noted that the third preset number is set according to the actual situation.

[0068] The following introduces a specific example to illustrate in detail the control method of the electric heating tube in this embodiment, which specifically includes the following steps:

[0069] Step 1. Requirement analysis and initialization:

[0070] Obtain the target temperature T_target and the preset allowable error ΔT. Start the system, apply a PWM signal with an initial low duty cycle D_init to the electric heating tube for preheating, and at the same time start temperature monitoring.

[0071] Step 2. Real-time temperature and thermal field monitoring:

[0072] Real-time monitor the current core temperature T_core of the heated medium (electric heating tube) through at least one main temperature sensor, and monitor the temperatures at different axial positions or the surrounding medium of the electric heating tube through at least two auxiliary temperature sensors, and calculate the maximum temperature difference ΔT_field. At the same time, monitor the system input voltage U and current I, and calculate the instantaneous heating power P_inst in real time.

[0073] Step 3. Multi-control mode strategy:

[0074] According to the real-time state, the system automatically enters one of the following three control modes:

[0075] Fast heating-up mode strategy: When T_core < T_target - ΔT - δ (δ is the preset heating-up lag threshold), the system enters the fast heating-up mode strategy.

[0076] Approaching equilibrium mode strategy: When T_core enters the interval [T_target - ΔT - δ, T_target], the system enters the approaching equilibrium mode strategy.

[0077] Steady-state maintenance mode strategy: When T_core > T_target and |T_core - T_target| < ΔT, the system enters the steady-state maintenance mode strategy.

[0078] Step 4. Dynamic control execution based on multi-segment PWM and thermal field feedback:

[0079] Under each control mode strategy, the following core algorithm is used to generate control signals:

[0080] S4.1: Power reference calculation: Based on the deviation between T_core and T_target, a reference power demand Preq is calculated according to the PID algorithm or fuzzy control algorithm.

[0081] S4.2: Dynamic Generation of Multi-Segment PWM Parameters: Abandoning fixed-period PWM, the control cycle is divided into N (N≥3) consecutive sub-time periods. Each sub-time period is assigned an independent duty cycle D_n (n=1, 2...N). Wherein, ∑(D_n*t_n) / total cycle duration = the average duty cycle of Preq.

[0082] In the rapid heating mode strategy: N is small, the duty cycle is high and concentrated in the sub-time period to provide strong and continuous heating force.

[0083] In the approaching equilibrium mode strategy: N is increased, and a thermal field equilibrium factor α (α is positively correlated with ΔT_field) is introduced. When ΔT_field increases, the algorithm automatically adjusts the duty cycle distribution of each sub-time period. For example, it slightly increases the duty cycle in the heating time period corresponding to the lower temperature region, or adopts an alternating distribution of "high-low-high-low" overall to promote heat conduction and reduce ΔT_field.

[0084] In steady state, the modal strategy is to maximize N, finely adjust the duty cycle of sub-time periods near extremely low levels, and shift the main objective to offset heat dissipation, maintain the stability of T_core, and minimize ΔT_field.

[0085] S4.3: Overload and Failure Protection: Real-time monitoring of P_inst. If P_inst remains above the rated power or the current is abnormal, a cooling cycle is forced and an alarm is triggered. If a temperature sensor fails, the system switches to a degraded control mode based on the remaining sensors.

[0086] Step 5: Iterative Execution and Adaptive Learning

[0087] Repeat steps two through four until the heating process is complete. The system can record the optimal control parameter sets (such as N value, α coefficient relationship, etc.) under different operating conditions, forming a historical database for initial parameter optimization in subsequent similar heating tasks, thus achieving adaptive learning.

[0088] This embodiment implements the above method through the following modules, specifically including:

[0089] Data acquisition module: used to acquire temperature, voltage, and current signals.

[0090] Core processing and control module: It has a built-in algorithm program to execute control methods and generate multi-segment PWM control signals.

[0091] Multi-segment PWM drive module: Receives parameter instructions from the core processing module, generates specific PWM waveforms with segmented adjustable duty cycles, and drives power switching devices (such as MOSFETs and solid-state relays).

[0092] Heating element and load: as the controlled object.

[0093] Human-computer interaction module: used to set target parameters and display status.

[0094] This example offers the following benefits: 1. Significantly improved heating efficiency: By using multi-segment PWM to provide concentrated energy during the rapid heating phase and achieving fine-tuning in the steady-state phase, energy waste is reduced and the time to reach the target temperature is shortened. 2. Excellent thermal uniformity: By introducing the thermal field temperature difference ΔT_field as a feedback quantity and designing a thermal field equalization factor α to dynamically adjust the PWM distribution, the uniform spatial distribution of heat is effectively promoted, improving heating quality and product consistency (e.g., in industrial ovens). 3. Extended heating element lifespan: Avoiding the drastic hot and cold cycles under traditional on / off control, the staggered, gentle heating of multi-segment PWM, especially the approach phase, reduces thermal stress impact, thereby extending the heating element's lifespan. 4. Enhanced system adaptability and reliability: Possessing multi-mode switching, power protection, sensor failure degradation handling, and adaptive learning capabilities, the system can adapt to complex and changing working environments, making it more intelligent and reliable.

[0095] Specifically, take the electric heating element assembly in an industrial hot air circulating oven as an example.

[0096] I. Initialization: Set the oven target temperature T_target = 150℃ (degrees Celsius), ΔT = 2℃, δ = 5℃. Start the system and preheat for 1 minute with a duty cycle of D_init = 15%.

[0097] II. Monitoring: The main sensor (located in the air duct) monitors T_core, and four auxiliary sensors are located at the four corners of the oven. The calculated T_core = 25℃, ΔT_field = 10℃ (due to initial unevenness).

[0098] III. Decision and Execution: Since T_core (25℃) is much lower than (150-2-5=143℃), the rapid heating mode strategy is activated. The core PID calculates P_req=90% of the full power. The system uses N=3 multi-segment PWM with the waveform: [90%, 95%, 85%] (each segment lasts 1 second) for efficient heating.

[0099] IV. Dynamic Adjustment: When T_core reaches 140℃, the system enters a near-equilibrium mode strategy. At this time, ΔT_field is still 5℃. The system switches to multi-segment PWM with N=5 and calculates α=0.4. The control algorithm generates waveforms such as [70%, 50%, 75%, 45%, 80%]. This staggered heating is beneficial for heat convection and equalization within the chamber. ΔT_field gradually decreases to 2℃.

[0100] V. Steady-state maintenance: Once T_core reaches 149℃ and stabilizes, it enters mode three (precise steady state). A PWM with N=8 is used, with the duty cycle finely adjusted between [10%, 15%] to primarily compensate for heat loss, maintaining T_core between 148-152℃, while keeping ΔT_field within 1℃.

[0101] VI. Throughout the process, the system continuously monitored the power and no abnormalities were detected. After the work was completed, the system saved the temperature rise curve from room temperature to 150℃ and the parameters used for reference in future similar tasks.

[0102] Example 2

[0103] Corresponding to the aforementioned embodiments of the control method for electric heating tubes, this disclosure also provides embodiments of the control system for electric heating tubes.

[0104] Figure 2 The present disclosure provides a schematic diagram of a control system for an electric heating element, the control system comprising:

[0105] Module 1 is used to determine the control mode strategy based on the current core temperature, target temperature and preset error of the electric heating tube.

[0106] Module 2 is used to acquire parameters for a preset number of different sub-time periods corresponding to the control modality strategy.

[0107] The control mode strategy includes multiple PWM cycles, with the total duration of all sub-time periods equal to the duration of a single PWM cycle. Sub-time parameters include at least the sub-time period duration and the sub-time period duty cycle. The sum of the first ratios is the same as the average duty cycle of the reference power. The first ratio is the ratio of the first product to the duration of a single PWM cycle, where the first product is the product of the sub-time period duration and the sub-time period duty cycle.

[0108] In an alternative implementation, the reference power is determined based on the difference between the current core temperature and the target temperature, according to a PID algorithm or a fuzzy control algorithm.

[0109] Heating module 3 is used to heat the electric heating tube in segments according to the sub-time period parameters and the preset sub-time period parameters.

[0110] In an optional implementation, the determining module 1 is further configured to determine a rapid heating mode strategy in response to the current core temperature being less than a first difference.

[0111] The first difference is the difference between the target temperature, the preset allowable error, and the preset heating lag threshold; the rapid heating mode strategy corresponds to the first preset number of different sub-time period parameters.

[0112] In an optional implementation, the determining module 1 is further configured to determine a convergent equilibrium mode strategy in response to the current core temperature being less than or equal to the target temperature and the current core temperature being greater than or equal to a first difference.

[0113] Among them, the approaching equilibrium mode strategy corresponds to a second preset number of different sub-time period parameters; the second preset number is greater than the first preset number.

[0114] In one optional implementation, the duty cycle of the sub-period corresponding to the equilibrium mode strategy is determined based on the thermal field equilibrium factor and the weighting function.

[0115] Among them, the thermal field equilibrium factor is positively correlated with the maximum temperature difference, which is the maximum temperature difference between the current core temperature and the current axial temperature of the electric heating tube, or the current core temperature of the electric heating tube and the current temperature of the surrounding medium.

[0116] In an optional implementation, the determining module 1 is further configured to determine a steady-state maintenance mode strategy in response to the current core temperature being greater than the target temperature and the preset allowable error being greater than the second difference.

[0117] The second difference is the difference between the current core temperature and the target temperature, and the steady-state maintenance mode strategy corresponds to a third preset number of different sub-time period parameters; the third preset number is greater than the second preset number.

[0118] For the system embodiments, since they basically correspond to the method embodiments, the relevant parts can be referred to in the description of the method embodiments. The system embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separate, and the components as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this disclosure according to actual needs.

[0119] Example 3

[0120] Figure 3This is a schematic diagram of the structure of an electronic device according to an example embodiment of the present disclosure. The electronic device includes a memory, a processor, and a computer program stored in the memory and used to run on the processor. When the processor executes the computer program, it implements the control method of the electric heating tube described in any of the above embodiments. Figure 3 The electronic device 90 shown is merely an example and should not impose any limitation on the functionality and scope of use of the embodiments disclosed herein.

[0121] like Figure 3 As shown, the electronic device 90 can be manifested as a general-purpose computing device, such as a server device. The components of the electronic device 90 may include, but are not limited to: at least one processor 91, at least one memory 92, and a bus 93 connecting different system components (including memory 92 and processor 91).

[0122] Bus 93 includes a data bus, an address bus, and a control bus.

[0123] The memory 92 may include volatile memory, such as random access memory (RAM) 921 and / or cache memory 922, and may further include read-only memory (ROM) 923.

[0124] The memory 92 may also include a program tool 925 (or utility) having a set (at least one) program module 924, such program module 924 including but not limited to: an operating system, one or more application programs, other program modules, and program data, each or some combination of these examples may include an implementation of a network environment.

[0125] The processor 91 executes various functional applications and data processing by running computer programs stored in the memory 92, such as the control method for the electric heating tube provided in any of the above embodiments.

[0126] Electronic device 90 can also communicate with one or more external devices 94 (e.g., keyboard, pointing device, etc.). This communication can be performed through input / output (I / O) interface 95. Furthermore, electronic device 90 can also communicate with one or more networks (e.g., local area network (LAN), wide area network (WAN), and / or public network, such as the Internet) via network adapter 96. As shown, network adapter 96 communicates with other modules of electronic device 90 via bus 93. It should be understood that, although not shown in the figure, other hardware and / or software modules can be used in conjunction with electronic device 90, including but not limited to: microcode, device drivers, redundant processors, external disk drive arrays, RAID (disk array) systems, tape drives, and data backup storage systems.

[0127] It should be noted that although several units / modules or sub-units / modules of the electronic device have been mentioned in the detailed description above, this division is merely exemplary and not mandatory. In fact, according to embodiments of this disclosure, the features and functions of two or more units / modules described above can be embodied in one unit / module. Conversely, the features and functions of one unit / module described above can be further divided and embodied by multiple units / modules.

[0128] Example 4

[0129] This disclosure also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the control method for the electric heating tube provided in any of the above embodiments.

[0130] The readable storage medium may be more specifically adopted, including but not limited to: portable disk, hard disk, random access memory, read-only memory, erasable programmable read-only memory, optical storage device, magnetic storage device, or any suitable combination thereof.

[0131] Example 5

[0132] This disclosure also provides a computer program product, including a computer program that, when executed by a processor, implements the control method for the electric heating tube described in any of the above embodiments.

[0133] The program code for executing the computer program product of this disclosure can be written in any combination of one or more programming languages, and the program code can be executed entirely on a user device, partially on a user device, as a stand-alone software package, partially on a user device and partially on a remote device, or entirely on a remote device.

[0134] While specific embodiments of this disclosure have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of this disclosure is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of this disclosure, but all such changes and modifications fall within the scope of protection of this disclosure.

Claims

1. A method for controlling an electric heating element, characterized in that, The control method for the electric heating element includes: Based on the current core temperature, target temperature, and preset error of the electric heating element, a control mode strategy is determined. Obtain a preset number of different sub-time period parameters corresponding to the control mode strategy; The control mode strategy includes multiple PWM cycles, and the total duration of all sub-time periods is the duration of a single PWM cycle. The sub-time parameters include at least the sub-time duration and the sub-time duty cycle. The sum of the first ratios is the same as the average duty cycle of the reference power. The first ratio is the ratio of the first product to the duration of a single PWM cycle, and the first product is the product of the sub-time duration and the sub-time duty cycle. The electric heating tube is heated in segments according to the execution order of the sub-time period parameters and the preset sub-time period parameters.

2. The control method for the electric heating tube as described in claim 1, characterized in that, The step of determining the control mode strategy based on the current core temperature, target temperature, and preset error of the electric heating element includes: In response to the current core temperature being less than a first difference, a rapid heating mode strategy is determined; wherein, the first difference is the difference between the target temperature, a preset allowable error, and a preset heating lag threshold; the rapid heating mode strategy corresponds to a first preset number of different sub-time period parameters.

3. The control method for the electric heating tube as described in claim 2, characterized in that, The step of determining the control mode strategy based on the current core temperature, target temperature, and preset error of the electric heating tube further includes: In response to the current core temperature being less than or equal to the target temperature, and the current core temperature being greater than or equal to the first difference, an equilibrium-approaching mode strategy is determined. The approach-equilibrium mode strategy corresponds to a second preset number of different sub-time period parameters; the second preset number is greater than the first preset number.

4. The control method for the electric heating element as described in claim 3, characterized in that, The step of determining the control mode strategy based on the current core temperature, target temperature, and preset error of the electric heating tube further includes: In response to the current core temperature being greater than the target temperature and the preset allowable error being greater than the second difference, a steady-state maintenance mode strategy is determined. Wherein, the second difference is the difference between the current core temperature and the target temperature, and the steady-state maintenance mode strategy corresponds to a third preset number of different sub-time period parameters; the third preset number is greater than the second preset number.

5. The control method for the electric heating element as described in claim 1, characterized in that, The reference power is determined based on the difference between the current core temperature and the target temperature using a PID algorithm or a fuzzy control algorithm.

6. The control method for the electric heating tube as described in claim 3, characterized in that, The duty cycle of the sub-period corresponding to the approach-equilibrium mode strategy is determined based on the thermal field equilibrium factor and the weighting function. The thermal field equalization factor is positively correlated with the maximum temperature difference, which is the maximum temperature difference between the current core temperature and the current axial temperature of the electric heating tube, or the maximum temperature difference between the current core temperature of the electric heating tube and the current temperature of the surrounding medium.

7. A control system for an electric heating element, characterized in that, The control system for the electric heating element includes: The determination module is used to determine the control mode strategy based on the current core temperature, target temperature and preset error of the electric heating tube; The acquisition module is used to acquire a preset number of different sub-time period parameters corresponding to the control mode strategy; The control mode strategy includes multiple PWM cycles, and the total duration of all sub-time periods is the duration of a single PWM cycle. The sub-time parameters include at least the sub-time duration and the sub-time duty cycle. The sum of the first ratios is the same as the average duty cycle of the reference power. The first ratio is the ratio of the first product to the duration of a single PWM cycle, and the first product is the product of the sub-time duration and the sub-time duty cycle. The heating module is used to heat the electric heating tube in segments according to the sub-time period parameters and the preset sub-time period parameters in an execution order.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and for running on the processor, characterized in that, When the processor executes the computer program, it implements the control method for the electric heating tube according to any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the control method for the electric heating tube as described in any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the control method for the electric heating tube as described in any one of claims 1-6.

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