Method for controlling an aerosol generating device

Abstract

A method 200 for controlling an aerosol generating device 100 is disclosed. The method 200 includes receiving operating parameters of the aerosol generating device 100, where the operating parameters include an ambient temperature and an aspect of power supplied to an inductor 102 of the aerosol generating device 100, determining an estimated temperature of a susceptor 108 disposed within a consumable 106 of the aerosol generating device 100 based on the operating parameters, where the estimated temperature is determined during inductive heating of the susceptor 102 by the inductor 108, and controlling the power supplied to the inductor 102 based on the estimated temperature of the susceptor 108.

Description

[Technical Field]

[0001] The present invention relates to a method and apparatus for controlling an aerosol generating device. In particular, the method involves estimating the temperature within a consumable of the aerosol generating device. The present disclosure is particularly applicable to portable aerosol generating devices that can heat, rather than burn, tobacco or other suitable aerosol substrate material through inductive heating of a susceptor located within the consumable. [Background technology]

[0002] The popularity and use of risk-reducing or risk-modifying devices (also known as vaporizers) has grown rapidly in recent years as an aid to assisting regular smokers who wish to quit using traditional tobacco products, such as cigarettes, cigars, cigarillos, and rolling cigarettes. A variety of devices and systems are available that heat or warm aerosolizable substances, as opposed to burning tobacco in traditional tobacco products.

[0003] A commonly available risk reduction or risk modification device is the substrate heated aerosol generator or heat-not-burn (HNB) device. This type of device generates an aerosol or vapor by heating an aerosol substrate (i.e., consumable), which typically contains moist tobacco or other suitable aerosolizable material, to temperatures typically ranging from 150°C to 300°C. By heating rather than burning or combusting the aerosol substrate, an aerosol is released that contains the components desired by the user but is free of the by-products of combustion and burning. Furthermore, aerosols produced by heating tobacco or other aerosolizable material typically do not contain the burnt or bitter taste that can result from combustion, which can be unpleasant to users.

[0004] In certain non-heated combustion devices, an induction coil may be used to inductively heat a susceptor disposed within the aerosol substrate, transferring thermal energy from the susceptor to the surrounding substrate. However, in such devices, the susceptor is insulated within the aerosol substrate, which can make it difficult to monitor the heating process and precisely control the aerosol generation characteristics of the device.

[0005] For example, inadequate information about conditions within the aerosol substrate may result in vapor temperatures that are too high or too low, potentially resulting in an unpleasant user experience or a user safety hazard. Furthermore, it may not be possible to ensure a consistent inhalation experience, i.e., to provide the same inhalation quality from puff to puff, consumable to consumable, and / or flavor to flavor. Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention aims to address one or more of these problems. [Means for solving the problem]

[0007] According to a first aspect of the present invention, there is provided a method for controlling an aerosol generating device, the method comprising: receiving operating parameters of the aerosol generating device, wherein the operating parameters include an ambient temperature and an aspect of power supplied to an inductor of the aerosol generating device; determining an estimated temperature of a susceptor disposed within a consumable of the aerosol generating device based on the operating parameters, wherein the estimated temperature is determined during inductive heating of the susceptor by the inductor; and controlling the power supplied to the inductor based on the estimated temperature of the susceptor.

[0008] In this manner, a method for monitoring an induction heating process is provided that does not require the placement of a temperature sensor within the consumable. As a result, the power supplied to the inductor can be varied according to the estimated temperature of the susceptor to regulate the temperature of the consumable and control the aerosol generation characteristics of the device. The temperature of the susceptor can be estimated using a thermal model that outputs a value for the internal temperature within the consumable. Advantageously, the ambient temperature and the power supplied to the inductor are readily measurable parameters that can provide a reliable estimate of the internal temperature of the consumable, and therefore the temperature of the susceptor located within the consumable.

[0009] The temperature of the consumables may be controlled using a closed-loop control system. Thus, the temperature and heating of the consumables may be adjusted without the need for human interaction. The heat generated by the susceptor and transferred to the surrounding consumables may be controlled according to the estimated temperature of the susceptor. Advantageously, this may protect the susceptor and consumables from overheating or ensure that steam at an optimal temperature is produced. In one example, the heating of the susceptor may be controlled so that the temperature of the susceptor follows a pre-characterized temperature profile.

[0010] Preferably, the method further comprises measuring the ambient temperature and the manner in which the power is supplied to the inductor of the aerosol generating device.

[0011] Preferably, the aspect of the power supplied to the inductor includes at least one of a current supplied to the inductor, a voltage supplied to the inductor, and a wattage supplied to the inductor.

[0012] Preferably, the power supplied to the inductor is controlled using a proportional-integral-derivative, PID, controller, thus using a control loop feedback mechanism to provide accurate and responsive correction of the susceptor temperature based on the estimated susceptor temperature.

[0013] Preferably, the power supplied to the inductor is controlled based on the difference between the estimated temperature of the susceptor and the target temperature of the susceptor. For example, a PID controller may continuously calculate an error value as the difference between the target temperature and the estimated temperature and apply a correction based on a proportional term, an integral term, and a derivative term.

[0014] Preferably, the method further comprises cutting off power to the inductor when the estimated temperature of the susceptor reaches a threshold value, thereby preventing overheating of the consumable.

[0015] Preferably, the estimated temperature of the susceptor is determined based on the operating parameters of the aerosol-generating device and on the thermal properties of the consumable. Preferably, the thermal properties of the consumable include heat capacity and thermal resistance. In particular, the thermal properties of the consumable may be properties of the aerosol substrate or aerosol-generating material within the consumable, such as the heat capacity and thermal resistance of tobacco. In this way, a thermal model can be used to estimate the temperature at the center of the consumable using the ambient temperature and the power supplied to the inductor as measurands and the heat capacity and thermal resistance of the consumable as fixed parameters.

[0016] Preferably, the method further includes updating the thermal properties of the consumable during induction heating of the susceptor. It is known that the properties (e.g., thermal properties) of the consumable can change throughout the heating operation. For example, the heat capacity of tobacco is known to increase as the moisture content of the tobacco increases or as the temperature of the tobacco increases. Furthermore, the thermal resistance of tobacco is known to decrease as the temperature of the tobacco increases. Therefore, it is advantageous to correct and update the thermal properties of the consumable during the heating operation. In this way, a more accurate estimate of the temperature of the susceptor can be provided.

[0017] Preferably, the method further includes measuring the temperature of the outer surface of the consumable using a temperature sensor, and updating the thermal properties of the consumable based on the measured temperature. The temperature measured at the outer surface of the consumable depends on the internal temperature of the consumable, the power induced in the susceptor, the heat capacity of the consumable, and the thermal resistance of the consumable. Therefore, the heat capacity and thermal resistance can be updated during the heating process based on the relationship between the temperature measured at the outer surface of the consumable and the operating parameters of the aerosol generation device.

[0018] Preferably, the method further includes calculating an estimated temperature of the exterior surface of the consumable, and updating the thermal properties of the consumable based on the difference between the measured temperature of the exterior surface of the consumable and the estimated temperature of the exterior surface of the consumable.

[0019] Preferably, the updated characteristics of the consumable are determined using at least one of an extended Kalman filter, a recursive least squares filter, a constant variation method, or a characteristic mapping method.

[0020] According to another aspect of the present invention, there is provided an aerosol generating device including processing circuitry configured to perform the above method and a temperature sensor configured to measure ambient temperature.

[0021] According to another aspect of the invention, there is provided a computer readable medium containing executable instructions that, when executed by a processing circuit, cause the processing circuit to perform the above-described method.

[0022] According to another aspect of the invention, there is provided a computer program product comprising instructions that, when executed by a processing circuit, cause the processing circuit to perform the method described above. [Brief explanation of the drawings]

[0023] Embodiments of the present invention will be described with reference to the following drawings.

[0024] [Figure 1] 1 is a schematic diagram of the internal components of an aerosol generating device in accordance with one embodiment of the present invention. [Figure 2] 1 is a flowchart illustrating method steps for operation of an aerosol generating device in accordance with one embodiment of the present invention. [Figure 3] FIG. 1 is a schematic diagram illustrating a thermal model used to estimate the temperature of a susceptor in a consumable aerosol generating device. [Figure 4] 1 is a flowchart illustrating method steps for updating thermal properties of a consumable in one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0025] FIG. 1 is a schematic diagram of the internal components of an aerosol-generating device 100 according to one embodiment of the present invention. The aerosol-generating device 100 is a heat-non-combustion device that uses an induction heating system to generate an aerosol (also known as a vapor). In particular, the aerosol-generating device 100 includes one or more inductors 102 and a heating chamber 104 configured to receive a consumable 106. Each inductor 102 typically includes a wire or other conductor wound into a coil around a magnetic core. The consumable 106 includes an aerosol-generating material, such as tobacco or another suitable material, that releases an aerosol when heated to an aerosolization temperature. A susceptor 108 is positioned within the consumable 106 such that the susceptor 108 is surrounded by the aerosol-generating material. Preferably, the susceptor 108 is located at the center or core of the consumable 106. For example, the consumable 106 may include a rod of aerosol-generating material, with the susceptor 108 located at a central position along the cylindrical axis of the rod. The susceptor 108 comprises a conductive material such as graphite, silicon carbide, molybdenum, or stainless steel.

[0026] In use, a power source, such as a battery (not shown), is used to generate a high-frequency alternating current. The current is supplied to one or more inductors 102, generating a time-varying magnetic field. The susceptor 108 is positioned within the generated magnetic field, and the alternating electromagnetic field induces eddy currents within the susceptor 108. This heats the susceptor 108, which transfers thermal energy to the aerosol-generating material surrounding the consumable 106, thereby increasing the temperature of the consumable 106. When the consumable 106 (i.e., the aerosol-generating material) exceeds the aerosolization temperature, an aerosol is generated that can be inhaled by a user.

[0027] The aerosol-generating device 100 further includes a temperature sensor 110 disposed within (or adjacent to) the heating chamber 104. The temperature sensor 110 contacts the consumable 106 received within the heating chamber 104 and is configured to measure the temperature of the consumable 106. In this manner, the temperature sensor 110 is operable to measure the temperature of the consumable 106 at an exterior surface 112 of the consumable 106. Preferably, the exterior surface 112 is an exposed surface of the aerosol-generating material such that the temperature sensor 110 contacts the aerosol-generating material held within the consumable 106.

[0028] In one example, the temperature sensor 110 may be a resistance temperature detector, such as a platinum resistance thermometer (PRT). In other examples, the temperature sensor 110 may be another type of temperature sensor, such as a thermocouple, a negative temperature coefficient (NTC) thermistor, or a semiconductor-based sensor.

[0029] Those skilled in the art will appreciate that in some embodiments, the temperature sensor 110 may be absent.

[0030] The aerosol generating device 100 may further include processing circuitry (not shown) for controlling the operation of the components of the aerosol generating device 100.

[0031] FIG. 2 illustrates a method 200 of operating the aerosol generating device 100 in accordance with one embodiment of the present invention.

[0032] In step 202, a target temperature for the susceptor 102 is received at the aerosol-generating device 100. For example, the target temperature may be predefined in the processing circuitry. Additionally or alternatively, a target temperature profile may be received at the aerosol-generating device 100 such that the target temperature varies throughout the heating operation. For example, the target temperature may be higher in the early stages of the heating operation.

[0033] In step 204, an error (e.g., difference) between the target temperature and the estimated temperature of the susceptor 108 is calculated. The estimated temperature of the susceptor 108 is described further below. The error may be calculated by processing circuitry.

[0034] In step 206, the power supplied to the one or more inductors 102 is controlled based on the estimated temperature of the susceptor 108. In particular, the power supplied to the one or more inductors 102 is controlled based on the error between the target temperature of the susceptor 108 and the estimated temperature. For example, if the estimated temperature of the susceptor 108 is below the target temperature of the susceptor 108, the power supplied to the one or more inductors 102 may be increased. Similarly, if the estimated temperature of the susceptor 108 is above the target temperature of the susceptor 108, the power supplied to the one or more inductors 102 may be decreased. In this manner, the temperature of the susceptor 108 can be determined without having to place a temperature probe within the consumable 106, and the temperature of the consumable 106 can then be adjusted to protect the susceptor 108 and consumable 106 from overheating and / or to ensure that steam is generated at an optimal temperature.

[0035] The power supplied to the one or more inductors 102 may be controlled using a proportional-integral-derivative (PID) controller, which calculates an error value as the difference between the target temperature and the estimated temperature of the susceptor 109, and adjusts the power supplied to the one or more inductors 102 based on a proportional term, an integral term, and a derivative term.

[0036] In some examples, the amount of power supplied to the one or more inductors 102 may also be controlled based on the energy transfer efficiency from the one or more inductors 102 to the susceptor 108. The energy transfer efficiency is the ratio of energy converted to useful heat energy at the susceptor 108 compared to the total energy supplied to the one or more inductors 102. For example, if the energy transfer efficiency is 0.4, then 40 W of power supplied to the one or more inductors will produce 16 W of power at the susceptor. The energy transfer efficiency of the aerosol generating device 100 may be pre-characterized during product development.

[0037] In step 208, operating parameters of the aerosol generation device 100 are received at the aerosol generation device 100. The operating parameters include (and optionally consist of) the power supplied to the one or more inductors 102 and the ambient temperature of the aerosol generation device 100. In particular, the ambient temperature corresponds to the temperature of the aerosol generation device 100 away from the heating chamber 104 (i.e., a location not affected by the heating effect of the susceptor 108). For example, the ambient temperature may correspond to a temperature measured at a processing circuit (e.g., a circuit board or controller) of the aerosol generation device 100. Thus, the ambient temperature preferably corresponds to the initial temperature of the consumable 106 before the heating process begins.

[0038] Optionally, the method 200 may further include measuring the power supplied to the one or more inductors 102 and measuring the ambient temperature of the aerosol generation device 100. For example, the power supplied to the one or more inductors 102 may be measured using a power meter (e.g., a current and voltage sensor) at the one or more inductors 102. The ambient temperature may be measured using a temperature sensor located at a location away from the heating effects of the susceptor 108, for example, in the processing circuitry.

[0039] In step 210, an estimated temperature of the susceptor 108 is determined. This is accomplished by estimating the internal temperature of the consumable 106. In particular, the temperature of a single point within the consumable 106 corresponding to the location of the susceptor 108 may be estimated. In one example, the temperature of the center of the consumable 106 may be estimated.

[0040] The estimated temperature of the susceptor 108 is calculated based on the power supplied to the one or more inductors 102 and the ambient temperature of the aerosol-generating device 100, i.e., the operating parameters. The calculation is also based on the thermal properties of the consumable 106. In particular, the thermal properties include (and optionally consist of) the thermal resistance and heat capacity of the consumable 106 (i.e., the thermal resistance and heat capacity of the aerosol-generating material within the consumable 106, e.g., the cigarette).

[0041] The initial (e.g., default) values ​​of thermal resistance and heat capacity may be measured and / or calculated before the aerosol generating device 100 is first operated, i.e., before the consumable 106 is heated. For example, the initial values ​​may be pre-characterized during product development of the aerosol generating device 100.

[0042] However, it is known that the thermal properties of the consumable 106 tend to change during the heating process. For example, the heat capacity of tobacco is known to increase as the moisture content of the tobacco increases or as the temperature of the tobacco increases. Furthermore, the thermal resistance of tobacco is known to decrease as the temperature of the tobacco increases. Thus, in some embodiments, the thermal properties of the consumable 106 may be updated or adjusted during the heating operation. That is, method 200 may further include steps 212 and 214.

[0043] In step 212, the temperature of the exterior surface 212 of the consumable 106 is measured by the temperature detector 110. Preferably, the exterior surface 212 is an exposed surface of the aerosol-generating material such that the temperature of the aerosol-generating material is measured by the temperature detector 110.

[0044] In step 214, the thermal properties of the consumable 106 (e.g., the thermal properties of the aerosol-generating material) are updated. In particular, the thermal resistance and heat capacity of the consumable 106 are updated based on the temperature measured at the exterior surface 212 of the consumable 108. This may be accomplished by comparing the measured temperature of the exterior surface 112 of the consumable 108 with the estimated temperature of the exterior surface 112 of the consumable 108 and calculating corrective values ​​for the thermal resistance and heat capacity based on the error, e.g., calculating adjusted values ​​for the thermal resistance and heat capacity that minimize the error. The process of updating the thermal properties is described in further detail below with reference to FIG. 4.

[0045] The updated thermal properties are then used in step 210 where an estimated temperature of the susceptor 108 is calculated based on the operating parameters of the aerosol generating device 100 and the thermal properties of the consumable 106 .

[0046] Of course, one skilled in the art will appreciate that steps 212 and 214 are optional, and that in some embodiments, the thermal properties of the consumable 106 may not be updated during the heating process, in which case initial (e.g., default) values ​​for thermal resistance and heat capacity are always used when calculating the estimated temperature of the susceptor 108 in step 210, not just during the first cycle of the method 200.

[0047] The temperature estimation may be performed by a processing circuit that may utilize a thermal model such as that described with reference to FIG. 3 . For example, the thermal model may receive as input the power supplied to the one or more inductors 102 and the ambient temperature of the aerosol generation device 100 (i.e., operating parameters). The thermal model may also receive and / or access the thermal resistance and heat capacity of the consumable 106. Initially, the thermal model may receive initial (e.g., default) values ​​for the thermal resistance and heat capacity of the consumable 106. However, once a heating operation begins, the thermal model may receive updated values ​​for the thermal resistance and heat capacity of the consumable 106. The thermal model may use these values ​​to output an estimated temperature of the susceptor 108.

[0048] In one example, power to one or more inductors 102 may be stopped when the estimated temperature of the susceptor 108 reaches a threshold value. For example, this may prevent overheating of the consumable 106 or may allow for an adaptive preheat period of the consumable 106 in which the consumable 106 is preheated until the internal temperature of the consumable 106 reaches a threshold value.

[0049] After step 210, the method 200 returns to step 204, where the estimated temperature of the susceptor 108 determined in step 210 is compared to the target temperature of the susceptor 108 and a new error is calculated. The power supplied to the one or more inductors 102 is adjusted using the newly calculated error in step 206, and an adjusted value for the power supplied to the one or more inductors 102 is received in step 208, and so on.

[0050] 3 is a schematic diagram illustrating a thermal model 300 that can be used to estimate the temperature of the susceptor 108. The thermal model 300 can be implemented using processing circuitry in the aerosol generating device 100. For example, the thermal model 300 can be implemented using software or can be implemented by physical circuitry, e.g., without the need for an external controller.

[0051] The thermal model 300 is a thermal circuit model that models the flow of heat by analogy with an electric circuit. The flow of heat is represented by a current, the temperature is represented by a voltage, the heat source is represented by a constant current source, the thermal resistance is represented by a resistor, and the thermal capacitance is represented by a capacitor.

[0052] As can be seen in Figure 3, - TIFF0007762170000001.tif7170 is the power dissipated in the susceptor 108 (i.e., the rate of heat flow from the susceptor 108), - C T is the heat capacity of the consumable 106, -R cond is the thermal resistance of the consumable 106 to heat transfer by conduction, -R convis the thermal resistance of the consumable 106 to heat transfer by convection, -R rad is the thermal resistance of the consumable 106 to heat transfer by radiation, -T int is the internal temperature of the consumable 106 (corresponding to the temperature of the susceptor 108), -T sensor is the temperature measured at the exterior surface 112 of the consumable 108 by the temperature sensor 110; -T amb is the ambient temperature measured away from the heating influence of the susceptor 108.

[0053] The power dissipated in the susceptor 108 is equal to the ratio of the heat flow in the two parallel paths. TIFF0007762170000002.tif11170

[0054] The heat capacity of the consumable 106 is defined as: where ΔQ is the amount of heat that must be added to the consumable 106 body (of mass M) to raise the temperature of the consumable 106 body (of mass M) by ΔT. Therefore, TIFF0007762170000004.tif7170 can be represented as follows:

number

[0055] Therefore, the internal temperature of the consumables, T C of, TIFF0007762170000012.tif8170,R total , T amb and C T A person skilled in the art can estimate the It will be appreciated that the power delivered to the one or more inductors 102 and the efficiency of energy transfer to the susceptor 108 can be calculated based on pre-characterized values.

[0056] The thermal model 300 may also be used to update the thermal resistance and capacitance values ​​based on the temperature measured at the exterior surface 112 of the consumable 108. Again, for a given heat flow The temperature drop ΔT at a given absolute thermal resistance R in TIFF0007762170000014.tif8170 is Using the general principle given by TIFF0007762170000015.tif8170, The file name would be TIFF0007762170000016.tif8170. If you replace TIFF0007762170000017.tif10170, This gives TIFF0007762170000018.tif15170.

[0057] Therefore, using this relationship, C T and R cond The value of T sensor , i.e., the temperature measured at the exterior surface 112 of the consumable 106. For example, T sensor The measured value of is the T estimated using the above formula. sensor can be compared with the estimate of CT and R cond The value of can be adjusted to minimize the error between the measured and estimated values.

[0058] Of course, it will be understood that thermal model 300 is just one possible thermal model according to the present invention, and that other thermal models may be used to determine the estimated temperature and obtain updated thermal properties of susceptor 108.

[0059] 4 illustrates a method 400 for updating thermal properties of a consumable 106 in one embodiment of the present invention. Method 400 may form part of method 200.

[0060] While initial (e.g., default or pre-characterized) values ​​of the thermal resistance and thermal capacitance of the consumable 106 may be used to estimate the temperature of the susceptor 108, the thermal properties of the consumable 106 are known to change over time, and therefore it is advantageous to continuously update the thermal properties during operation of the aerosol generation device 100. For example, factors such as dirt in the heating chamber 104, aging of parts, moisture content, manufacturing tolerances, or different compositions of the consumable 106 can lead to fluctuations in the values ​​of thermal resistance and thermal capacitance over the life of the aerosol generation device 100. Therefore, updating the values ​​of thermal resistance and thermal capacitance during operation of the aerosol generation device 100 leads to more accurate temperature estimation of the susceptor 106 and, therefore, improved performance of the aerosol generation device 100.

[0061] Initially, the thermal resistance and thermal capacitance values ​​used to calculate the estimated temperature of the susceptor 108 may be initial (e.g., default) values ​​pre-characterized during product development. However, once heating operations of the aerosol generating device 100 begin, updated values ​​of the thermal resistance and thermal capacitance can be obtained using method 400. The updated values ​​of the thermal resistance and thermal capacitance can then be used to calculate the estimated temperature of the susceptor 108.

[0062] The method 400 begins at step 402, where an estimated temperature of the exterior surface 112 of the consumable 106 is calculated. For example, the temperature of the exterior surface 112 of the consumable 106 may be calculated using a thermal model, such as the thermal model 300 described above.

[0063] In step 404 , the actual temperature of the exterior surface 112 of the consumable 106 is measured using the temperature sensor 110 .

[0064] In step 406, the measured temperature of the exterior surface 112 of the consumable 106 is compared to the estimated temperature of the exterior surface 112 of the consumable 106, and the thermal properties of the consumable 106 are updated based on the difference between these values. In particular, the thermal capacity and thermal resistance values ​​of the consumable 106 may be adjusted to minimize the error between the measured temperature and the estimated temperature of the exterior surface 112 of the consumable 106.

[0065] In one example, the error may be minimized (thermal properties may be updated) using an extended extended Kalman filter. In another example, a recursive least squares filter may be used. In another example, a constant variation method may be used. In another example, a property mapping method may be used.

[0066] Thereafter, in step 210 of method 200, the updated values ​​of thermal resistance and thermal capacitance may be used to calculate an estimated temperature of susceptor 108. For example, the updated values ​​of thermal resistance and thermal capacitance may be fed back to thermal model 300 or another suitable thermal model. The updated values ​​may replace the initial values ​​of thermal resistance and thermal capacitance or may replace the current values ​​(i.e., the previous updated values) of thermal resistance and thermal capacitance.

[0067] Of course, those skilled in the art will understand that if the initial (or current) values ​​of thermal resistance and thermal capacitance are optimal, i.e., the values ​​already minimize the error between the measured temperature and the estimated temperature of the exterior surface 112 of the consumable 106, the values ​​of thermal resistance and thermal capacitance may not need to be updated.

Claims

1. 1. A method of controlling an aerosol generating device, comprising: receiving operating parameters of the aerosol generating device, wherein the operating parameters include: Ambient temperature, and Aspects of power supplied to the inductor of the aerosol generating device Including, determining an estimated temperature of a susceptor disposed within a consumable of the aerosol generating device based on the operating parameters and based on thermal characteristics of the consumable, wherein the thermal characteristics of the consumable include a heat capacity and a thermal resistance, and the estimated temperature is determined during inductive heating of the susceptor by the inductor; controlling the power supplied to the inductor based on the estimated temperature of the susceptor; A method comprising:

2. The manner in which the power is supplied to the inductor is a current supplied to the inductor; the voltage supplied to the inductor; and The wattage supplied to the inductor The method of claim 1 , comprising at least one of:

3. The method of claim 1 or 2, wherein the power supplied to the inductor is controlled using a proportional-integral-derivative, PID, controller.

4. The method of claim 1 , wherein the power supplied to the inductor is controlled based on a difference between the estimated temperature of the susceptor and a target temperature of the susceptor.

5. The method of claim 1 , further comprising: deactivating power to the inductor when the estimated temperature of the susceptor reaches a threshold value.

6. The method of claim 1 , further comprising updating the thermal properties of the consumable during the inductive heating of the susceptor.

7. measuring the temperature of an exterior surface of the consumable using a temperature sensor; updating the thermal properties of the consumable based on the measured temperature; The method of claim 6 further comprising:

8. calculating an estimated temperature of the exterior surface of the consumable; updating the thermal characteristic of the consumable based on a difference between the measured temperature of the exterior surface of the consumable and the estimated temperature of the exterior surface of the consumable; The method of claim 7 further comprising:

9. The updated thermal property of the consumable is: Extended Kalman filter, Recursive least squares filter, Constant variation method, or Feature Mapping Method The method of any one of claims 6 to 8, wherein the temperature is determined using at least one of:

10. 10. An aerosol generating device comprising a processing circuit configured to carry out the method of any one of claims 1 to 9.

11. A computer readable medium comprising executable instructions that, when executed by a processing circuit, cause the processing circuit to perform the method of any one of claims 1 to 9.

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