Heating control method and device for multi-boiling-point substances

Abstract

The invention provides a heating control method and device for a multi-boiling-point substance, and the device comprises a heating control circuit for the multi-boiling-point substance, and the heating control circuit for the multi-boiling-point substance comprises an MOS switch chip with a current detection function, which is used for copying the current of a heating wire branch in real time, and obtaining the power and resistance information of a heating wire; the control unit is used for storing a calibration curve model and a self-adaptive algorithm and controlling pulse driving heating parameters; the heating wire is used for being in contact with the multi-boiling-point substance and achieving heating through pulse driving. The self-adaptive algorithm adjusts the proportion and step length design of the positive pulse and the negative pulse, tobacco tar heating is efficiently carried out, and the temperature is constant. By the adoption of the technical scheme, a heating system and a detection system can be fused at extremely low cost, the optimal boiling working point is found out through the self-adaptive algorithm, and multi-boiling-point substances such as electronic cigarette tobacco tar can be heated and controlled at low cost without an additional temperature sensor.

Description

Technical Field

[0001] The present invention relates to the field of electronic technology, and in particular to a heating control method and device for multi-boiling point substances. Background Art

[0002] At present, for heating multi-boiling point substances such as e-cigarette oil, a constant resistance heating wire is mostly used. However, the composition of e-cigarette oil is complex, and the heating effects of different e-cigarette oils under the same heating method vary significantly. To ensure the atomization effect, many designs choose to overheat the e-cigarette oil, resulting in increased energy consumption, and at the same time seriously affecting the taste and user experience, such as problems like overheated or overcooled smoke or difficult-to-control duration, and the experience is not good.

[0003] For the scheme of detecting temperature based on the load characteristics, most are applicable to single-boiling point systems (such as water). Even if a highly non-linear metal material is used, an ultra-high-precision ADC chip still needs to be equipped, and its cost often far exceeds the overall cost of the e-cigarette. In addition, the heating module and the detection module are independent of each other. Even without using an additional temperature sensor, the overall occupied space is still large. Moreover, due to the uncertainty of the boiling point of the e-cigarette oil, it may exceed the working range of the ADC chip. If a wide-range ADC chip is replaced, the cost will be further increased. Therefore, this technology is difficult to be applied to e-cigarettes.

[0004] High-end e-cigarettes often collect data through an external temperature sensor, transmit it to a microcontroller (MCU), and adjust the load power after processing to achieve temperature control. However, this scheme has obvious defects: First, the temperature sensor has a response lag. When the load temperature changes rapidly, due to the limitation of the heat exchange efficiency, accurate data cannot be obtained in time, and it is difficult to achieve high-order control and prediction. Second, the sensor is easily affected by the ambient temperature. In extreme temperatures or when the temperature changes violently, the data reliability decreases, and exceeding the designed temperature range will cause the sensor to fail and the feedback system to collapse. Third, the sensor needs to be attached to or indirectly attached to the load. In some special scenarios (such as the heating filament), it is difficult to install due to space limitations or load characteristics requirements, and the practicability is poor. Fourth, adding a temperature sensor will increase the material and space costs, and the algorithm processing difficulty will increase. In an extreme and difficult-to-maintain environment, the damage of the sensor will seriously affect the system reliability and it is difficult to meet the requirements of low-cost and miniaturized devices.

[0005] In summary, when designing a low-cost and high-efficiency multi-boiling point temperature heating control system for e-cigarettes, traditional sensor schemes face many challenges in terms of cost, speed, and efficiency, and the non-temperature sensor detection scheme based on the ADC chip also has the problem of too high cost. The most potential optimization direction is to develop a system without a temperature sensor, integrating heating and detection functions, and using the temperature load characteristics to achieve precise heating and control of the critical boiling point of multi-boiling point e-cigarette oil with the lowest chip cost and the smallest space occupation. Summary of the Invention

[0006] In view of the above technical problems, the present invention discloses a heating control method and device for multi-boiling-point substances, solving the reliability problems of relative detection of the boiling points of multiple substances, heating rate, temperature control, and cost integration.

[0007] For this, the technical solution adopted by the present invention is as follows:

[0008] A heating control device for multi-boiling-point substances, which includes a heating control circuit for multi-boiling-point substances. The heating control circuit for multi-boiling-point substances includes:

[0009] A MOS switch chip with a current detection function, which is used to proportionally copy the current of the heating wire branch in real time and obtain the power and resistance information of the heating wire;

[0010] A control unit, which is used to store a calibration curve model and an adaptive algorithm, and control the pulse drive heating parameters;

[0011] A heating wire, which is used to contact the multi-boiling-point substance and realize heating through pulse drive;

[0012] The adaptive algorithm includes:

[0013] A temperature state difference module, which is used to determine the difference state between the current temperature and the target boiling point temperature according to the obtained power and resistance information of the heating wire;

[0014] A PID module, which is used to generate an adjustment signal according to the difference state;

[0015] A data processing module, which is used to perform data processing;

[0016] A comparator module, which is used for data comparison to obtain the increase or decrease value of the positive pulse step length;

[0017] An adaptive increment step module, which dynamically adjusts the duty cycle step lengths of the positive pulse and the negative pulse;

[0018] A load temperature rise state determination module, which judges the temperature rise trend based on the change rate of the power dissipation of the heating wire.

[0019] The present invention also discloses a heating control method for multi-boiling-point substances, which is controlled by using the above-mentioned heating control device for multi-boiling-point substances, and includes the following steps:

[0020] Step S1, calibrating data: obtaining a calibration curve by means of a constant pulse or a constant heating superimposed pulse, establishing a model, and obtaining the load power dissipation turning points corresponding to multiple boiling points; obtaining the relative levels of multiple boiling points through the time of the pulse energy of the heating wire, and recording the optimal working boiling point temperature of the multi-boiling-point substance in this calibration state as the target;

[0021] Step S2, using an adaptive pulse driving algorithm to drive the heating wire, the adaptive pulse driving algorithm dynamically adjusts the positive pulse duty cycle according to the power dissipation change rate, gradually increases the pulse width when the target is not reached, and reduces the pulse width when approaching the target to suppress overheating; during the heating process, the adaptive algorithm repeatedly adjusts the ratio and step size of the positive pulse and the negative pulse to maintain the temperature at each time point at the target value.

[0022] As a further improvement of the present invention, in step S2, the adaptive pulse driving algorithm calculates the time required for the next positive half-cycle in the negative half-cycle based on the change in power dissipation in the positive half-cycle, and the time required for the next positive half-cycle is the time of the previous positive half-cycle plus or minus a step size limited by the maximum and minimum values.

[0023] As a further improvement of the present invention, in step S2, when it is necessary to maintain a specific temperature or to lower the temperature, a dynamic balance is achieved by relying on natural heat dissipation and the value of the positive half-cycle of the power pulse.

[0024] As a further improvement of the present invention, the pulse width is gradually increased when the target is not reached, and the pulse width is reduced when approaching the target to suppress overheating, including: increasing the positive duty cycle time until it approaches the target value, and determining the proportion of the positive pulse width and the proportion of the negative pulse width in the next cycle by the rising change of temperature.

[0025] As a further improvement of the present invention, in step S2, if the temperature gradually approaches the target value and the temperature rise rate is less than the set threshold, the proportion of the positive pulse width is reduced and the proportion of the negative pulse width is increased, so as to suppress the temperature from rising too quickly. At this time, the proportion of the negative pulse width can be appropriately increased so that natural heat dissipation can play a cooling role.

[0026] The technical solution of the present invention utilizes a MOS chip with integrated current detection function and a heating wire combination circuit with strong nonlinearity to integrate the heating module and the detection module. The controller's adaptive dynamic PWM pulse energy algorithm drives the acquisition of transient power differentiation, and then predicts the multiple boiling points of electronic cigarette oil substances to achieve high-efficiency heating.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] By adopting the technical solution of the present invention, the heating system and the detection system can be integrated at a very low cost, and the optimal boiling operating point can be found through an adaptive algorithm, thereby solving the problem of heating and controlling multi-boiling point substances such as electronic cigarette oil without the need for additional temperature sensors at a low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a boiling point calibration curve of boiling points of multiple substances in the embodiment of the present invention.

[0030] Figure 2 This is the pulse change diagram adjusted by the adaptive pulse driving algorithm according to the curve in the embodiment of the present invention.

[0031] Figure 3 This is the control flow chart of the heating control device for multi-boiling point substances in the embodiment of the present invention. Detailed implementation manners

[0032] The following further elaborates on the preferred embodiments of the present invention.

[0033] In order to solve the reliability problem of the integrated relative detection of the heating speed, temperature control, and cost of the boiling points of multiple substance states mentioned above, the present invention proposes a heating control device for multi-boiling point substances, which can be used for the efficient heating of multi-boiling point substances in e-cigarette oil.

[0034] The device includes a heating control circuit for multi-boiling point substances, and the heating control circuit for multi-boiling point substances includes:

[0035] A MOS switch chip with a current detection function, which is used to proportionally copy the current of the heating wire branch in real time and obtain the power and resistance information of the heating wire. The MOS switch combination non-linear heating wire circuit with the high-precision current detection ability integrated in the chip is used to obtain the power and resistance information of the heating wire. The way to obtain the current is that there is a small MOS transistor with an N:1 (N is the ratio of the actual current to the output current) inside, which proportionally copies the current of the heating wire branch in real time.

[0036] A control unit, which is used to store a calibration curve model and an adaptive algorithm, and control the pulse drive heating parameters; the control unit includes an MCU;

[0037] A heating wire, which is used to contact the multi-boiling point substance and realize heating through pulse drive; the MOS switch chip with a current detection function is connected to the heating wire, and the heating wire is immersed in contact with the multi-boiling point substance. At this time, it is connected to the current detection and the output end of the MOS through the MCU. At this time, the adaptive algorithm is written into the storage of the MCU to ensure the normal operation of the system.

[0038] The adaptive algorithm includes:

[0039] A temperature state difference module, which is used to determine the difference state between the current temperature and the target boiling point temperature according to the obtained power and resistance information of the heating wire;

[0040] A PID module, which is used to generate an adjustment signal according to the difference state;

[0041] A data processing module, which is used to perform data processing;

[0042] A comparator module, which is used to compare data and obtain the increased or decreased value of the positive pulse step;

[0043] An adaptive incremental step module that dynamically adjusts the duty cycle step of positive and negative pulses;

[0044] A load temperature rise state determination module that judges the temperature rise trend based on the change rate of the power dissipation of the heating wire.

[0045] The control method using the above-mentioned heating control device for multi-boiling point substances includes:

[0046] First, calibrate the data. Obtain the boiling point calibration curve of the multi-boiling point substance in the form of constant pulse heating or constant heating superimposed with constant pulse heating, as Figure 1 shown, and establish a model in the microcontroller (MCU). At this time, the turning points of the load power dissipation corresponding to multiple boiling points will be obtained. Since the energy dissipation will change significantly when heating to the boiling point of the substance, it can be judged by the time of the pulse energy of the heating wire, the relative levels of multiple boiling points of the e-cigarette oil are obtained, and the optimal working boiling point temperature of the multi-boiling point substance of the e-cigarette oil in this calibration state is automatically recorded, for example, near the third boiling point, as the heating target temperature.

[0047] Secondly, drive using an adaptive pulse drive algorithm, which specifically includes: Since the heating wire is pulse-driven, different from the constant heating form on the market, there are differences between the positive half-cycle and the negative half-cycle during the heating process. Assume that the positive half-cycle is for heating and the negative half-cycle is in the off state. As Figure 2As shown, the algorithm will use the heating data change rate during the positive half-cycle (i.e., the change in power dissipation during this cycle). Assuming it is in the state of waiting to be heated, the algorithm will calculate the time required for the next positive half-cycle during the negative half-cycle time (i.e., the time of the last positive half-cycle plus or minus a step size, and this step size has maximum and minimum limits). Therefore, it will be realized that when not approaching the target value, it will gradually increase until heating with the maximum pulse energy. To maintain a specific temperature or cool down, it depends on the dynamic balance between natural heat dissipation and the value of the positive half-cycle of the power pulse, and at this time, the temperature can be maintained or controlled to decrease. As shown in the following figure, when not reaching the target value of the multi-boiling point, the time of the positive duty cycle will be increased until approaching the target value. And by judging the rising change of the temperature, it is determined that more energy needs to be given in the next cycle, so the proportion of the positive pulse width in the next cycle is increased (since it is found that the temperature needs to rise, the proportion of the negative pulse width can be appropriately reduced at this time). When the temperature gradually approaches the target value (i.e., near a certain boiling point), it is found that the rising speed of the temperature is slow, so the proportion of the positive pulse width will be reduced to inhibit the too-fast rise of the temperature (at this time, the proportion of the negative pulse width can be appropriately increased so that natural heat dissipation can play a role in cooling). By continuously feeding back the above process, finally, the adaptive search and balance of the boiling point can be realized at a specific pulse frequency and pulse width. It should be noted that we do not need to know exactly the specific value of the boiling point, nor do we need to fix the heating time, because the heating state and the maintenance of the optimal boiling working point are completely found by itself.

[0048] The flowchart of the whole process is as Figure 3 shown, that is, through the PID algorithm of the loop, according to the algorithm to adjust the proportion and step size design of the positive and negative pulses, the heating of the e-liquid and the temperature constancy are carried out efficiently to ensure that the target value data can be maintained at all times.

[0049] In the above device and method, the output of the heating control circuit for multi-boiling point substances is the reference target value of the boiling point of the multi-boiling point substances detected by the algorithm, and the input of the adaptive algorithm part is the reference target value of the multi-boiling point substances. During operation, it will continuously repeat in the adaptive algorithm part module.

[0050] The temperature control module allows multiple heating devices to work simultaneously, crosswise, or partially. The multiple load environments can be in the same thermal stability system, or partially in the thermal stability system, or each in an independent thermal stability system. The MCU module is connected to different heating devices or loads at the same time, allowing the detection of the temperature of multiple different areas, constant temperature control, and the prediction of the load temperature in the local area.

[0051] Further, the heating control device for multi-boiling-point substances further includes a user interaction and monitoring module, which is configured to receive the monitoring information of different load environments from the MCU, and allows the user to detect, stabilize, and predict the load temperature status for different regions respectively.

[0052] Further, the heating control device for multi-boiling-point substances in this embodiment allows multiple heating devices to work simultaneously, crosswise, or partially, in multiple load environments. The multiple load environments can be in the same thermal stability system, or partially in the thermal stability system, or each in an independent thermal stability system. The MCU module can be connected to multiple temperature control modules simultaneously, allowing the detection of temperatures, constant temperature control, and prediction of load temperatures in partial areas of multiple different regions. The user interaction and monitoring module is configured to receive the monitoring information of different load environments from the MCU, and allows the user to detect, stabilize, and predict the load temperature status for different regions respectively.

[0053] The above content is a further detailed description of the present invention in combination with specific preferred embodiments. It cannot be determined that the specific implementation of the present invention is only limited to these descriptions. For those of ordinary skill in the technical field to which the present invention belongs, without departing from the concept of the present invention, several simple deductions or substitutions can be made, and all should be regarded as belonging to the protection scope of the present invention.

Claims

1. A heating control device for multi-boiling-point substances, characterized in that: It includes a heating control circuit for multi-boiling-point substances. The heating control circuit for multi-boiling-point substances includes: A MOS switch chip with current detection function, which is used to proportionally copy the current of the heating wire branch in real time and obtain the power and resistance information of the heating wire; A control unit, which is used to store the calibration curve model and adaptive algorithm and control the pulse drive heating parameters; A heating wire, which is used to contact the multi-boiling-point substance and realize heating through pulse drive; The adaptive algorithm includes: A temperature state difference module, which is used to determine the difference state between the current temperature and the target boiling point temperature according to the obtained power and resistance information of the heating wire; A PID module, which is used to generate an adjustment signal according to the difference state; A data processing module, which is used to process data; A comparator module, which is used to compare data and obtain the increase or decrease value of the positive pulse step length; An adaptive increment step module, which dynamically adjusts the duty cycle step lengths of the positive pulse and the negative pulse; A load temperature rise state determination module, which judges the temperature rise trend based on the power dissipation change rate of the heating wire.

2. A heating control method for multi-boiling-point substances, characterized in that: Controlling by using the heating control device for multi-boiling-point substances as described in claim 1, including the following steps: Step S1, calibrating data: obtaining a calibration curve by means of a constant pulse or a constant heating superimposed pulse, establishing a model, and obtaining the load power dissipation turning points corresponding to multiple boiling points; obtaining the relative levels of multiple boiling points through the time of the heating wire pulse energy, and recording the optimal working boiling point temperature of the multi-boiling-point substance in this calibration state as the target; Step S2, driving the heating wire by using an adaptive pulse drive algorithm. The adaptive pulse drive algorithm dynamically adjusts the positive pulse duty cycle according to the power dissipation change rate, gradually increases the pulse width when the target is not reached, and decreases the pulse width when approaching the target to suppress overheating; during the heating process, the adaptive algorithm repeatedly adjusts the ratio and step lengths of the positive pulse and the negative pulse to keep the temperature at each moment at the target value.

3. The heating control method for multi-boiling-point substances according to claim 2, characterized in that: In step S2, the adaptive pulse drive algorithm calculates the time required for the next positive half cycle in the negative half cycle based on the power dissipation change amount of the heating wire in the positive half cycle. The time required for the next positive half cycle is the time of the previous positive half cycle plus or minus a step length limited by the maximum value and the minimum value.

4. The heating control method for multi-boiling point substances according to claim 2, characterized in that: In step S2, when it is necessary to maintain a specific temperature or cool down, it relies on the natural heat dissipation and the value of the positive half cycle of the power pulse for dynamic balance.

5. The heating control method for multi-boiling point substances according to claim 2, characterized in that: The step of gradually increasing the pulse width when the target is not reached and decreasing the pulse width when approaching the target to suppress overheating includes: increasing the time of the positive duty cycle until approaching the target value, and determining the proportion of the positive pulse width and the proportion of the negative pulse width in the next cycle through the rising change of the temperature.

6. The heating control method for multi-boiling-point substances according to claim 5, characterized in that: In step S2, if the temperature gradually approaches the target value and the rising speed of the temperature is less than the set threshold, the proportion of the positive pulse width is reduced and the proportion of the negative pulse width is increased.

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