Aerosol generating device and control method

Abstract

One embodiment of the present application proposes an aerosol generating apparatus and a control method thereof. The aerosol generating apparatus includes a susceptor configured to be penetrated by a fluctuating magnetic field and generate heat to heat an aerosol-generating product, an oscillator including an induction coil and a capacitor configured to direct a fluctuating current through the induction coil to drive the induction coil and generate the fluctuating magnetic field, a peak detection unit configured to detect a peak voltage of the oscillator, and a controller configured to control the oscillator to direct a current based on the peak voltage. The aerosol generating apparatus monitors the peak voltage during the oscillator's oscillation process, and further controls the oscillator's oscillation based on the peak voltage.

Description

Technical Field

[0001] (Cross - reference to related applications) This application claims priority to Chinese Patent Application No. 202011442641.4, filed with the China National Intellectual Property Administration on December 8, 2020, with the title "Aerosol Generation Device and Control Method", and all of its contents are incorporated herein by reference.

[0002] Embodiments of the present application relate to the technical field of heated non - combustible low - temperature smoking devices, and more particularly to an aerosol generation device and a control method.

Background Art

[0003] Tobacco products (e.g., cigarettes, cigars, etc.) generate tobacco smoke by burning tobacco during use. As an alternative to these products that burn tobacco, attempts have been made to manufacture products that release compounds without burning.

[0004] Examples of such products include heating devices that release compounds by heating materials without burning them. For example, the material may be tobacco or other non - tobacco products, and these non - tobacco products may or may not contain nicotine. In known devices, a heater that generates heat by electromagnetic induction heats a tobacco product to generate smoking aerosols. As one prior art related to the above - mentioned heating device, in the embodiments of Chinese Patent No. 201580007754.2, an induction heating device for heating a special cigarette product by electromagnetic induction is proposed. Specifically, an induction coil and a capacitor are connected in series or in parallel to form an LC oscillation to form an alternating current, thereby generating an alternating magnetic field in the coil to inductively heat the susceptor to heat the cigarette product.

Summary of the Invention

[0005] Embodiments of the present application are aerosol generation devices configured to heat an aerosol - generating product to generate smoking aerosols, A susceptor configured to be penetrated by a variable magnetic field to generate heat and heat an aerosol generating product, An oscillator including an induction coil and a capacitor, configured to guide a variable current through the induction coil to drive the induction coil to generate a variable magnetic field, A peak detection unit configured to detect the peak voltage of the oscillator, A controller configured to control the oscillator to guide the variable current based on the peak voltage, and an aerosol generating device is provided.

[0006] The above aerosol generating device monitors the peak voltage in the oscillation process of the oscillator, and further controls the oscillator to guide the variable current based on the peak voltage.

[0007] Furthermore, the above circuit term "oscillator" is a circuit module composed of a capacitor and an inductor, which can generate periodically varying current and voltage. The term "peak voltage" is the maximum value in the period of the variable voltage.

[0008] In a preferred embodiment, the peak detection unit Includes a holding capacitor configured to hold the peak voltage of the oscillator.

[0009] In a preferred embodiment, the peak detection unit An operational amplifier located between the holding capacitor and the oscillator, and further an operational amplifier configured to output the voltage of the oscillator to the holding capacitor, A voltage follower configured to output the peak voltage of the oscillator held by the holding capacitor, and includes.

[0010] In a preferred embodiment, the peak detection unit Further includes a discharge switch configured to discharge the holding capacitor when turned on.

[0011] In a preferred embodiment, the sampling terminal of the operational amplifier is connected to the oscillator, the holding capacitor includes three paths, the first path of which is connected to the output terminal of the operational amplifier, the second path is connected to the discharge switch, and the third path is connected to the sampling terminal of the voltage follower.

[0012] In a preferred embodiment, the oscillator is a parallel LC oscillator including the inductor coil and the capacitor connected in parallel, the controller drives the parallel LC oscillator to oscillate using a pulse with a variable frequency, determines the optimal frequency of the parallel LC oscillator based on the peak voltage detected by the peak detection unit, and further controls the parallel LC oscillator to conduct the variable current based on the optimal frequency.

[0013] In a preferred embodiment, the controller is configured to determine the optimal frequency of the parallel LC oscillator based on the peak voltage detected by the peak detection unit when it is equal to or substantially close to a preset threshold voltage.

[0014] In a preferred embodiment, in the pulse with a variable frequency, the frequency gradually varies in descending order.

[0015] In a preferred embodiment, the oscillator is a parallel LC oscillator including the inductor coil and the capacitor connected in parallel, the controller drives the parallel LC oscillator to oscillate using a pulse with a variable duty ratio, determines the optimal duty ratio of the parallel LC oscillator based on the peak voltage detected by the peak detection unit, and further controls the parallel LC oscillator to conduct the variable current based on the optimal duty ratio.

[0016] In a preferred embodiment, the controller is configured to determine an optimal duty ratio of the parallel LC oscillator based on the peak voltage detected by the peak detection unit when the peak voltage is equal to or substantially close to a preset threshold voltage.

[0017] In a preferred embodiment, in the pulse of the variable duty ratio, the duty ratio gradually varies in ascending order.

[0018] In a preferred embodiment, the oscillator is a series LC oscillator or a series LCC oscillator including the inductor coil and the capacitor connected in series. The controller is configured to drive the oscillator to oscillate using a pulse of variable frequency and to determine the resonance frequency of the oscillator based on the peak voltage detected by the peak detection unit.

[0019] In a preferred embodiment, in the pulse of the variable frequency, the duty ratio is 50% and the frequency gradually varies in descending order.

[0020] In a preferred embodiment, the controller is configured to determine the resonance frequency of the oscillator based on the peak voltage detected by the peak detection unit when the peak voltage is at its maximum.

[0021] Another embodiment of the present application is a susceptor configured to be penetrated by a variable magnetic field to generate heat and heat an aerosol generating product, an oscillator including an inductor coil and a capacitor, the oscillator being configured to guide a variable current to flow through the inductor coil and drive the inductor coil to generate a variable magnetic field, and a control method for an aerosol generating device including the oscillator, the step of detecting a peak voltage of the oscillator, and the step of determining an oscillation frequency of the oscillator based on the peak voltage, further providing the control method.

[0022] In a preferred embodiment, the oscillation frequency of the oscillator is adjusted so that the oscillation frequency is equal to or substantially close to a preset frequency.

[0023] Another embodiment of the present application is a susceptor configured to be penetrated by a variable magnetic field to generate heat and heat an aerosol generating product, a parallel LC oscillator including an inductor coil and a capacitor connected in parallel, the parallel LC oscillator being configured to guide a variable current to flow through the inductor coil to drive the inductor coil to generate a variable magnetic field, and a control method of an aerosol generating device including the parallel LC oscillator, driving the parallel LC oscillator to oscillate according to a pulse whose frequency or duty ratio gradually varies; detecting a peak voltage of the parallel LC oscillator; comparing the peak voltage with a preset threshold voltage, and determining an optimal frequency or an optimal duty ratio of the parallel LC oscillator when the peak voltage is equal to or substantially close to the preset threshold voltage; driving the parallel LC oscillator to oscillate according to the optimal frequency or the optimal duty ratio, and further generating a variable magnetic field in the inductor coil. The control method is further provided.

[0024] Another embodiment of the present application is a susceptor configured to be penetrated by a variable magnetic field to generate heat and heat an aerosol generating product, a series LC oscillator or a series LCC oscillator having an inductor coil, the series LC oscillator or the series LCC oscillator being configured to guide a variable current to flow through the inductor coil to drive the inductor coil to generate a variable magnetic field, and a control method of an aerosol generating device including the series LC oscillator or the series LCC oscillator, driving the series LC oscillator or the series LCC oscillator to oscillate using a pulse having a constant duty ratio of 50% and a gradually varying frequency. A step of detecting the peak voltage of the series LC oscillator or the series LCC oscillator; A step of determining the resonance frequency of the series LC oscillator or the series LCC oscillator based on the maximum value of the peak voltage; A step of driving the series LC oscillator or the series LCC oscillator to oscillate according to the resonance frequency, and further generating a variable magnetic field in the induction coil, and further providing the control method.

[0025] In a preferred embodiment, in the pulse whose frequency gradually varies, the frequency gradually varies in descending order.

[0026] In a preferred embodiment, the step of determining that the peak voltage is the maximum value includes: Calculating a difference value between the currently detected peak voltage and the previously detected peak voltage; Determining whether the difference value is positive; When it is positive, reducing the frequency at which the series LC oscillator or the series LCC oscillator is driven to oscillate, and when it is not positive, determining that the previously detected peak voltage is the maximum value.

[0027] In a preferred embodiment, the step of reducing the frequency at which the series LC oscillator or the series LCC oscillator is driven to oscillate includes: Determining whether the difference value is greater than a predetermined value. When it is greater than the predetermined value, reducing the frequency at which the series LC oscillator or the series LCC oscillator is driven to oscillate according to a first amplitude. When it is not greater than the predetermined value, reducing the frequency at which the series LC oscillator or the series LCC oscillator is driven to oscillate according to a second amplitude, where the first amplitude is greater than the second amplitude. Here, the first amplitude is greater than the second amplitude.

[0028] Another embodiment of the present application is an aerosol generating device configured to heat an aerosol generating product to generate a smoking aerosol, A parallel LC oscillator including an inductive coil and a capacitor connected in parallel, configured to guide a varying current through the inductive coil to drive the inductive coil to generate a varying magnetic field, and a parallel LC oscillator; A susceptor configured to be penetrated by the varying magnetic field to generate heat and further heat an aerosol generating product received in the cavity; A transistor switch; A controller configured to control the on / off of the transistor switch by a pulse, further drive the parallel LC oscillator to oscillate, and guide a varying current to flow through the inductive coil, and includes; Further provided is an aerosol generating device in which a duty ratio of the pulse is greater than 50%.

[0029] In a preferred embodiment, the duty ratio of the pulse is greater than 70%.

Brief Description of the Drawings

[0030] One or more embodiments are exemplarily illustrated by the figures in the corresponding accompanying drawings. These exemplary descriptions do not limit the embodiments. Elements with the same reference numerals in the drawings represent similar elements. Unless otherwise specified, the figures in the accompanying drawings do not limit the scale.

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Mode for Carrying Out the Invention

[0031] To facilitate the understanding of the present application, the present application will be described in more detail below in association with the drawings and specific embodiments.

[0032] One embodiment of the present application proposes an aerosol generator, and its structure is as shown in FIG. 1, a cavity in which an aerosol generating product A is removably received, an induction coil L for generating a variable magnetic field under an alternating current, A susceptor 30 at least partially extending within the cavity, inductively coupled to the induction coil L, penetrated by a variable magnetic field to generate heat, and further configured to heat an aerosol generating product A, such as a cigarette, to volatilize at least one component of the aerosol generating product A to form a smoking aerosol. A rechargeable DC battery cell, a battery cell 10 capable of outputting a DC current. A circuit 20 that is appropriately electrically connected to the rechargeable battery cell 10 to convert the DC current output from the battery cell 10 into an alternating current having an appropriate frequency and then supply it to the induction coil L.

[0033] According to the settings in the use of the product, the induction coil L may include a cylindrical inductor coil wound in a spiral shape as shown in FIG. 1. The cylindrical induction coil L wound in a spiral shape may have a radius r within the range of about 5 mm to about 10 mm, and in particular, the radius r may be about 7 mm. The length of the cylindrical induction coil L wound in a spiral shape may be within the range of about 8 mm to about 14 mm, and the number of turns of the induction coil L is within the range of about 8 turns to 15 turns. Accordingly, the inner volume may be from about 0.15 cm 3 to about 1.10 cm 3 within the range.

[0034] In a more preferred embodiment, the frequency of the alternating current supplied from the circuit 20 to the induction coil L is in the range of 80 KHz to 400 KHz. More specifically, the frequency may be in the range of about 200 KHz to 300 KHz.

[0035] In a preferred embodiment, the DC supply voltage provided by the battery cell 10 is within the range of about 2.5 V to about 9.0 V, and the number of amperes of the DC current that can be provided by the battery cell 10 is within the range of about 2.5 A to about 20 A.

[0036] In a preferred embodiment, the susceptor 30 is substantially pin-shaped or blade-shaped, which is further advantageous for insertion into the aerosol generating product A. Also, the susceptor 30 may have a length of about 12 millimeters, a width of about 4 millimeters, and a thickness of about 0.5 millimeters, and may be made of stainless steel (SS430) of grade 430. As an alternative embodiment, the susceptor 30 may have a length of about 12 millimeters, a width of about 5 millimeters, and a thickness of about 0.5 millimeters, and may be made of stainless steel (SS430) of grade 430. In other modified embodiments, the susceptor 30 may further be structured in a cylindrical or tubular shape. In use, its internal space forms a cavity for receiving the aerosol generating product A, and generates a smoking aerosol by heating the outer periphery of the aerosol generating product A. These susceptors may further be made of stainless steel (SS420) of grade 420, and an iron / nickel-containing alloy material (e.g., permalloy).

[0037] In the embodiment shown in FIG. 1, the aerosol generating device further includes a holder 40 for arranging the induction coil L and the susceptor 30, and the material of the holder 40 may include a non-metallic material that can withstand high temperatures, such as PEEK or ceramic. In practice, the induction coil L is wound around and fixed to the outer wall of the holder 40. Also, as shown in FIG. 1, the holder 40 has a hollow tubular shape, and the space of its tubular hollow part forms the above-mentioned cavity for receiving the aerosol generating product A.

[0038] In an alternative embodiment, the susceptor 30 is made of the above-mentioned sensitive material, or a sensitive material coating is formed by electroplating or deposition on the outer surface of a heat-resistant base material such as ceramic.

[0039] The structure and basic components in a preferred embodiment of the above circuit 20 include, as shown in FIGS. 2 to 3, the following parallel LC oscillator 24 and transistor switch 23.

[0040] The parallel LC oscillator 24 is specifically formed by parallel connection of a capacitor C1 and an inductor coil L. Further, it oscillates by the provided pulse voltage, generates a fluctuating current supplied to the inductor coil L, thereby generates a fluctuating magnetic field to inductively heat the susceptor 30.

[0041] The transistor switch 23 includes a switch tube Q1, is alternately turned on and off, conducts current between the battery cell 10 and the parallel LC oscillator 24 to oscillate the parallel LC oscillator 24, forms a fluctuating current flowing through the inductor coil L, and thereby generates a fluctuating magnetic field in the inductor coil L. Naturally, in the preferred embodiment shown in FIG. 3, the switch tube Q1 is a general MOS transistor switch, and during connection, the MOS transistor switch receives the PWM drive signal of the switch tube driver 22 by the gate G and is turned on / off.

[0042] Furthermore, in a preferred embodiment, the on / off of the transistor switch 23 is controlled by the drive signal of the switch tube driver 22. Naturally, the drive signal of the switch tube driver 22 is issued based on the PWM-type pulse control signal from the received MCU controller 21.

[0043] In a preferred embodiment, the on-time and off-time of the switch tube Q1 are different, that is, the duty ratio for controlling and oscillating the parallel LC oscillator 24 in the PWM mode is not 50%. That is, the oscillation process of the parallel LC oscillator 24 is asymmetric, and the parallel LC oscillator 24 is maintained to have a sufficient oscillation voltage to maintain the strength of the magnetic field. In a preferred embodiment, the duty ratio for controlling the switch tube Q1 to be on in the PWM mode is about 70 - 80%. Specifically, FIG. 4 shows the variation process of the oscillation current / voltage in one cycle from time t1 to t5 when the parallel LC oscillator 24 of the circuit 20 shown in FIG. 3 is driven in a symmetric resonance mode with a duty ratio of 50%, which includes the following S1, S2, S3, and S4.

[0044] In S1, in the time period from t1 to t2, the switch tube driver 22 saturates and turns on the MOS transistor by sending a PWM pulse drive signal to the gate G of the MOS transistor Q1. After turning on, the current i1 flows from the positive electrode of the battery cell 10 through the induction coil L. Due to the inductive reactance of the coil, the current cannot change suddenly. Therefore, in the time period from t1 to t2, the induction coil L is charged to form a linearly increasing current i1.

[0045] In S2, in the time period from t2 to t3, at time t2, the PWM pulse ends and the MOS transistor Q1 is turned off. Similarly, due to the inductive reactance effect of the induction coil L, the current cannot immediately become 0, and the capacitor C1 is charged to generate a current i2 that charges the capacitor C1.

[0046] At time t3, the capacitor C1 is filled with charge and the current becomes 0. In this case, all the magnetic field energy of the induction coil L is converted into the electric field energy of the capacitor C1, reaching the peak voltage across both ends of the capacitor C1. The voltage formed between the drain D / source S of the MOS transistor Q1 is actually the sum of the reverse-phase pulse peak voltage and the positive electrode output voltage of the battery cell 10.

[0047] In S3, in the time period from t3 to t4, the capacitor C1 discharges until it is completed by the induction coil L. The current i3 reaches the maximum value, and the voltage across both ends of the capacitor C1 gradually decreases until it disappears. In this case, all the electrical energy in the capacitor C1 is also converted into the magnetic energy in the induction coil L. Similarly, due to the inductive reactance effect, the current flowing through the induction coil L gradually fluctuates, and the above S1 and S2 are in the opposite direction. The capacitor C1 discharges until the electromotive force across both ends of the induction coil L reverses.

[0048] In S4, in the time period from t4 to t5, when the MOS transistor Q1 is turned on again at time t4, a reflux is formed between the induction coil L and the filter capacitor C3. In this case, the energy of the induction coil L is kicked back to the filter capacitor C3 to form a current i4 that gradually decreases, and the cycle ends at time t5 when it decreases to 0. Then, the next oscillation cycle starts.

[0049] As can be seen from the description of the above process, the voltage between the drain D and source S of the MOS transistor Q1 crosses zero at time t4, and in the oscillation process, the on / off state of the MOS transistor Q1 is switched according to the zero-crossing point of the voltage between the drain D and source S.

[0050] Furthermore, in FIGS. 3 and 4, the synchronization detection unit 25 is for detecting the oscillation voltage of the parallel LC oscillator 24. Specifically, as shown in FIG. 3, the synchronization detection unit 25 mainly includes a zero-crossing comparator U1 for sampling and detecting the zero-crossing point of the drain D voltage signal of the MOS transistor Q1 so that only the MCU controller 21 controls the on / off switching of the MOS transistor Q1 according to the zero-crossing point.

[0051] In the embodiments of FIGS. 3 and 4, a peak detection unit 26 for detecting the peak voltage of the parallel LC oscillator 24 and controlling the output is further provided, which mainly includes the following operational amplifier U2, holding capacitor C2, and voltage follower U3.

[0052] The operational amplifier U2 has its sampling terminal in- connected to the drain D of the MOS transistor Q1, samples the voltage of the drain D of the MOS transistor Q1, and is used to output the operation result by the diode D2.

[0053] The holding capacitor C2 is connected to the output terminal of the operational amplifier U2, and the peak voltage output from the operational amplifier U2 can be held or locked by the holding capacitor C2. For example, in the time period from t2 to t3 of the voltage fluctuation period shown in FIG. 4, the operational amplifier U2 outputs a voltage value that gradually increases, and the holding capacitor C2 receives and accumulates the output voltage. Until the voltage value output from the operational amplifier U2 reaches the maximum at time t3, the voltage across the holding capacitor C2 also reaches the maximum synchronously. When time t3 passes, the output from the operational amplifier U2 gradually decreases to 0. However, since the holding capacitor C2 does not discharge, the voltage value across both ends is always held at the peak.

[0054] The voltage follower U3 follows and outputs the peak voltage held by the holding capacitor C2.

[0055] FIG. 5 shows a comparison between the input signal collected at the sampling terminal in- of the operational amplifier U2 of the peak detection unit 26 and the output signal output from the output terminal of the voltage follower U3 in two oscillation periods when driving the parallel LC oscillator 24 at a duty ratio of 70%. As can be seen from FIG. 5, what the peak detection unit 26 outputs is always the peak voltage of the parallel LC oscillator 24. Also, in FIG. 5, as can be seen from the waveform of the input signal, the time length during which a voltage peak appears in the input signal is much smaller than the time length close to substantially 0, that is, the oscillation is asymmetric. And as can be seen from the shape of the voltage peak in FIG. 5, the length of the time (t3) from the voltage close to substantially 0 (t2) to the peak voltage and the time length from the peak voltage to the voltage close to 0 (t4) are also different. Specifically, in FIG. 5, the rising speed to the peak is fast and the falling speed from the peak is slow. By adopting an asymmetric peak voltage much larger than the voltage in driving with a 50% duty ratio compared to the symmetric resonance with a 50% duty ratio in FIG. 4, further, in the process of driving and oscillating the parallel LC oscillator 24 at a 50% duty ratio, the problem of low efficiency due to the short charging time of the inductor coil L can be compensated. Based on the above tests of this application, in a preferred embodiment, the parallel LC oscillator 24 is driven to oscillate and heat with a pulse having a duty ratio greater than 50%. In a more preferred embodiment, the duty ratio is greater than 70%. By lengthening the charging time and shortening the discharging time in the oscillation period, the required power and voltage can be maintained.

[0056] With the above holding capacitor C2 and voltage follower U3, the output peak voltage can always be held at any time point during the oscillation process. Further, the MCU controller 21 can obtain or sample and detect the peak voltage of the oscillation at any time point.

[0057] In the preferred embodiment shown in FIG. 3, the operational amplifier U2 is used in the basic usage mode of a comparator. Specifically, when the reference signal input terminal in+ of the operational amplifier U2 is connected to one fixed signal of the output signal via a capacitor, the operational amplifier U2, as a comparator, outputs the result of the comparison operation between the oscillation voltage signal of the parallel LC oscillator 24 and the fixed reference signal. That is, when the voltage signal sampled at the sampling terminal in− of the operational amplifier U2 is higher than the reference voltage signal input at the input terminal in+, the operational amplifier U2 outputs the comparison result to the holding capacitor C2 for holding. When the voltage signal sampled at the sampling terminal in− reaches the peak, the voltage received by the holding capacitor C2 becomes the maximum, that is, the peak voltage.

[0058] Furthermore, in the preferred embodiment shown in FIG. 3, according to the conventional connection method of the follow - up output, the sampling terminal in+ of the voltage follower U3 is connected to the sampling terminal in+ of the operational amplifier U2. Also, the peak detection unit 26 further includes basic elements such as a plurality of resistors and capacitors used for the basic functions of voltage division, voltage stabilization, and current limiting.

[0059] Specifically, in the embodiment shown in FIG. 3, the negative terminal of the holding capacitor C2 in the peak detection unit 26 is grounded, and three paths are included in the connection of the positive terminal.

[0060] Among them, in the first path, it is connected to the output terminal of the operational amplifier U2 to receive the voltage output by the operational amplifier U2.

[0061] In the second path, it is connected to the sampling terminal in− of the voltage follower U3 so that the voltage follower U3 can output the peak voltage held by the holding capacitor C2.

[0062] In the third path, it is grounded through the switch tube Q2. The MCU controller 21 turns on the switch tube Q2 to discharge the positive terminal of the holding capacitor C2 to 0 so as to facilitate the sampling of the next oscillation peak voltage.

[0063] Another embodiment of the present application further provides a control method for automatically detecting or adjusting the oscillation frequency of the aerosol generator or the duty ratio of the pulse control signal based on the above peak detection unit 26.

[0064] FIG. 6 shows the steps of a control method for an aerosol generator that automatically detects and adjusts the oscillation frequency adapted to a predetermined duty ratio in the aerosol generator, including the following S10 and S20.

[0065] In S10, using a predetermined duty ratio, the MCU controller 21 transmits a series of pulse signals with gradually varying frequencies to the switch tube driver 22 to drive the switch tube Q1 to turn on / off, and further drives the parallel LC oscillator 24 to oscillate.

[0066] In S20, during the implementation of the above step S10, the peak detection unit 26 measures the peak voltage of the parallel LC oscillator 24, and when the measured peak voltage is equal to or very close to a preset voltage threshold, the desired optimal oscillation frequency is determined. Then, the MCU controller 21 inductively heats the susceptor 30 based on the determined optimal oscillation frequency.

[0067] In the above step S10, after setting a certain duty ratio (for example, 50% or 70%, etc.), a series of pulse signals including gradually varying frequencies are emitted to drive the parallel LC oscillator 24 to oscillate, searching for the relationship combination of the optimal frequency and duty ratio suitable for the desired output power by frequency sweeping. Subsequently, the parallel LC oscillator 24 is driven to oscillate according to this optimal frequency and duty ratio, and further controlled so that the susceptor 30 generates heat.

[0068] In the above preferred embodiments, as the pulse signal for frequency sweeping, it is preferable that the frequency of the pulse signal gradually decreases in descending order. When the duty ratio set in the frequency sweep is constant, when the frequency is high, the corresponding period is short, and the peak voltage of oscillation is proportional to the total current. The total current I is the integral of the current i and time t, denoted as Σ(di / dt). Accordingly, the peak voltage detected during the frequency sweep process varies in ascending order, which is advantageous for safely finding the frequency at a preset voltage threshold.

[0069] Also, in implementation, the number or count of pulses included in the pulse signal for frequency sweeping is maintained between 5 and 50, preferably between 5 and 10.

[0070] In a preferred embodiment, during the frequency sweep process, every time the peak voltage is detected, the switch tube Q2 is turned on to discharge the positive terminal of the holding capacitor C2 to 0, resetting the peak detection unit 26.

[0071] In the detection control where the circuit 20 operates, it is substantially unlikely that it is measured that the peak voltage is exactly the same as the preset voltage threshold. Further, usually, according to the implementation experience, when the error between the two is less than 0.25% of the preset voltage threshold, it is reasonable to determine that they are substantially close or very close and thus determine the detection result. For example, when the voltage peak at ideal optimal oscillation efficiency is 40V, in the actual frequency sweep measurement, if the detected peak voltage is 39V or more, it is almost considered that the optimal frequency has been found. Naturally, in other alternative embodiments, when there may be variations in each component and data stability during the operation of the circuit 20, if more accurate results can be achieved, the error determination criterion between the two may be further narrowed. For example, the error between the two may be less than 0.1% of the preset voltage threshold.

[0072] FIG. 7 shows the steps of a control method for an aerosol generator that automatically detects the duty ratio of the control signal of a parallel LC oscillator 24 that conforms to a predetermined frequency in another embodiment, including the following S11 and S21.

[0073] In S11, using a predetermined frequency, the MCU controller 21 emits a series of pulse signals with a gradually varying duty ratio to control the on / off of the switching tube Q1, and further drives the parallel LC oscillator 24 to oscillate. The above preset frequencies are, for example, 200KHz / 300KHz / 350KHz, etc. Of course, during the process of sweeping the duty ratio, the predetermined frequency is constant.

[0074] In S21, during the implementation of the above step S11, the peak detection unit 26 measures the peak voltage of the parallel LC oscillator 24, and when the measured peak voltage is equal to or very close to a preset voltage threshold, it is determined that the duty ratio corresponding to this peak voltage is the optimal duty ratio for the selected frequency. Subsequently, the parallel LC oscillator 24 is driven to oscillate according to the pulse signal of the duty ratio, and further the susceptor 30 is inductively heated.

[0075] In the above preferred embodiment, as the pulse signal for duty ratio sweeping, the duty ratio gradually increases in ascending order. When the frequency is constant during the duty ratio sweeping process, the larger the duty ratio, the longer the on-time of the corresponding switching tube Q1. Accordingly, the peak voltage detected during the duty ratio sweeping process varies in ascending order, which is advantageous for safely finding the frequency at the preset voltage threshold. Similarly, each time the peak voltage is detected during the detection process, the switching tube Q2 is turned on to discharge the positive end of the holding capacitor C2 to 0, and the peak detection unit 26 is reset.

[0076] In a specific embodiment, FIG. 8 shows a waveform diagram of the oscillation voltage of a pulse signal that sweeps and searches for the duty ratio at a predetermined frequency of 200 KHz (i.e., a period of 5 μs) and a threshold voltage of 40V. Starting from the on-time of 2 μs of the switch tube Q1 (i.e., a duty ratio of 2 μs / 5 μs = 40%), the on-time is increased by 0.2 μs for each pulse to sweep the duty ratio. When the sweep is performed with an on-time of 3.6 μs, the peak voltage is closest to 20V. Thereafter, if the parallel LC oscillator 24 is driven to oscillate at a duty ratio of 3.6 μs / 5 μs = 72% and a frequency of 200 KHz, it is optimal for obtaining the desired heating efficiency.

[0077] Here, the above threshold voltage of 40V is set based on the heating efficiency required for the product of an embodiment, and the value is taken based on the experience during the trial operation of the prototype. This value can not only ensure rapid temperature rise, but also cause no damage to the inverter circuit, and ensures a margin of about 25%.

[0078] In yet another embodiment, when the heating temperature or heating efficiency desired by the user changes, or when it is replaced with an aerosol generating product A that requires a different heating temperature, further, the required threshold voltage is adjusted, and the frequency sweep or duty ratio sweep is performed again as above to find a frequency or duty ratio suitable for the desired heating temperature or heating efficiency.

[0079] In the above method of the present application, the peak detection unit 26 can detect the peak voltage during the oscillation process. The peak voltage of the oscillation is correlated with the heating efficiency, and further, it can automatically search for an appropriate driving frequency or duty ratio according to the product or demand.

[0080] Another embodiment of the present application further provides a control method for an aerosol generating device that adaptively adjusts the oscillation frequency. As shown in FIG. 9, it includes the following S12 and S22.

[0081] In S12, the peak detection unit 26 detects the oscillation peak voltage of the parallel LC oscillator 24.

[0082] In S22, the MCU controller 21 determines the current oscillation frequency of the parallel LC oscillator 24 based on the detected oscillation peak voltage, and adjusts the magnitude of the drive frequency provided to the parallel LC oscillator 24 so that the oscillation frequency remains equal to or substantially close to the desired optimum frequency.

[0083] In this embodiment, the current oscillation frequency is calculated backward based on the correlation between the peak voltage and the frequency detected by the peak detection unit 26, and then the output frequency is adaptively adjusted to be equal to or substantially close to the preset oscillation frequency. In implementation, the object to be applied or detected can be applied to a series LC oscillator.

[0084] For example, FIG. 10 shows the structure and basic components of the circuit 20 of the series LCC oscillator 24a according to another embodiment of the present application. The series LCC oscillator 24a realizes resonance and further generates an alternating magnetic field in its internal induction coil L.

[0085] Here, in the oscillation process of the series LCC oscillator 24a, commutation is controlled by a half-bridge composed of the switch tube Q3 and the switch tube Q4. The on / off switching of the switch tube Q3 and the switch tube Q4 is controlled by the switch tube driver 22a. Specifically, the oscillation process of the series LCC oscillator 24a includes the following S100, S200, S300, and S400 as shown in FIGS. 11 to 12.

[0086] In S100, as shown in FIG. 11, when the switch tube Q3 is turned on and the switch tube Q4 is turned off, the battery cell 10 charges the capacitor C4 with the current i1, and the capacitor C3 discharges with the current i2. In this process, a current flowing through the induction coil L from left to right as shown in FIG. 11 is formed, which can be set as a positive current. In this stage S100, the capacitor C3 starts discharging when the switch tube Q3 is turned on and completes discharging until the voltage difference across both ends becomes 0, and the charging stops until the voltage across both ends of the capacitor C4 becomes equal to the output voltage of the battery cell 10. At this time, the current in the induction coil L has a resonance peak that is the largest.

[0087] In S200, even after the stage S100 is completed, the switching transistor Q3 remains turned on, and the switching transistor Q4 remains turned off. The inductor L discharges in the same direction as the current i2 in FIG. 1 to charge the capacitor C3. Thereby, the current flowing in the positive direction through the inductor L is gradually decreased, and the discharge of the inductor L ends until the current becomes zero. At this stage, since the discharge of the capacitor C3 is completed in the stage S100, the impedance between the inductor L and the circuit formed by the capacitor C3 via the switching transistor Q3 is basically zero. Therefore, in this stage S200, the inductor L mainly discharges to charge the capacitor C3, and the current flowing through the inductor L during the discharge process is the same as the current i2 in the stage S100. The capacitor C4 is charged to substantially the same output voltage as the battery cell 10 in the stage S100. In this stage S200, the inductor L compensates slightly for the second capacitor C2, but it may be basically ignored.

[0088] In the complete processes of the stage S100 and the stage S200, the total current flowing through the inductor L increases in the positive direction from zero to the maximum and then gradually decreases to zero due to the discharge of the inductor L. The direction of the current flowing through the inductor L is always in the positive direction from left to right.

[0089] In S300, after the step S200 is completed, the switching transistor Q3 is turned off, and the switching transistor Q4 is turned on. From the time when the switching transistor Q2 is turned on, a circuit of the current i3 and the current i4 shown in FIG. 12 is formed in the LCC oscillator 24a. According to the current path shown in FIG. 12, the current i3 forms a loop from the positive electrode of the battery cell 10, sequentially passing through the capacitor C3, the inductor L, the switching transistor Q4, and then returning to the negative electrode of the battery cell 10 through the ground. Also, the current i4 forms a loop from the positive terminal of the capacitor C4 in the counterclockwise direction shown in the figure, sequentially passing through the inductor L, the switching transistor Q4, and then returning to the negative terminal of the capacitor C4. During this process, a current flowing through the inductor L from right to left as shown in FIG. 12 is formed, which is opposite to the current direction in FIG. 11 and can be regarded as a negative-direction current.

[0090] In step S300, charging of capacitor C3 and discharging of capacitor C4 are both included simultaneously. The voltage of capacitor C3 increases until it becomes equal to the output voltage of battery cell 10. When the voltage difference across capacitor C4 is 0, the current in induction coil L has a resonance peak that is maximized.

[0091] In S400, even after step S300 is completed, the on state of switch tube Q2 is continuously maintained. Induction coil L charges capacitor C4 in the reverse direction, thereby gradually reducing the current flowing in the negative direction through induction coil L until the current becomes 0 due to the discharge of induction coil L.

[0092] In the complete process of these steps S300 and S400, the total current flowing through induction coil L similarly increases in the reverse direction from 0 to the maximum and then gradually decreases to 0 due to the discharge of induction coil L.

[0093] Therefore, in the oscillation process of the above LCC oscillator 24a, as shown in FIG. 13, the variation of the current flowing through induction coil L is such that one complete current cycle includes four parts corresponding to the above steps S100 / S200 / S300 / S400 in FIG. 13. From step S100 to step S400 above, the on / off states of switch tube Q3 and switch tube Q4 are alternately and cyclically switched, thereby cyclically generating the above oscillation process within LCC oscillator 24a and forming an alternating current flowing through induction coil L.

[0094] Therefore, as can be seen from the above control process, the LCC oscillator 24a in this embodiment undergoes inverse conversion by a ZCS (zero current switch) inverter topology different from the ZVS (zero voltage switch) inverter topology of the above parallel LC oscillator 24. And switch tube Q3 and switch tube Q4 are configured to perform on / off switching when the current flowing through induction coil L is 0.

[0095] During the commutation of the above LCC oscillator 24a during oscillation, the commutation is controlled by a half-bridge composed of the switch tube Q3 and the switch tube Q4. Naturally, based on the same embodiment, a person skilled in the art can drive the oscillation of the LCC oscillator 24a by replacing it with or adopting a full-bridge circuit including four switch tubes.

[0096] Furthermore, referring to the embodiment shown in FIG. 3, the half-bridge driver 22a employs a switch tube driver of the general model number FD2204, which is controlled in a PWM manner by the MCU controller 21. According to the pulse width of the PWM, high level / low level is alternately output by the third and tenth I / O ports respectively, and further drives the on-time of the switch tube Q3 and the switch tube Q4 to control the oscillation of the LCC oscillator 24a.

[0097] And, as can be seen from the above process, in the oscillation process of the above series LCC oscillator 24a, the current or voltage is a sine or cosine resonance change curve with symmetry, the duty ratio is substantially constant at 50%, and the corresponding MCU controller 21 drives the switch tube Q3 and the switch tube Q4 to be on or off with a PWM pulse signal of 50% duty ratio. In practice, the intensity of the resonant voltage and current progresses correlatively. For example, it varies as shown in FIG. 14. The resonant voltage progresses about 1 / 4 of the period ahead of the resonant current, and the entire LCC oscillator 24a shows weak inductance. "Capacitive" and "inductive" are electrical terms related to the series-parallel circuits of electronic devices (for example, LC oscillators or the above LCC oscillator 24a). When the capacitive reactance of a series-parallel circuit is greater than the inductive reactance, the circuit is "capacitive", and when the inductive reactance is greater than the capacitive reactance, the circuit is inductive. The state of "weak inductance" is a state where the inductive reactance and the capacitive reactance are substantially close, and the inductive reactance is not much larger but slightly larger than the capacitive reactance.

[0098] Similarly, in the embodiment shown in FIG. 10, the circuit 20 further includes a peak detection unit 26a for detecting the peak voltage of the LCC oscillator 24a.

[0099] In the above embodiment shown in FIG. 10, for example, a plurality of conventional basic elements are also included, such as resistors for voltage division, current limiting, and diodes for blocking reverse current, and capacitors for voltage stabilization or filtering.

[0100] Furthermore, the MCU controller 21 of the aerosol generator can similarly utilize the detection of the above peak detection unit 26a to search for the optimal output power or the frequency of the heating efficiency in a frequency sweep manner. In a specific embodiment, similar to the frequency sweep of the above parallel LC oscillator 24, a series of pulsed signals with varying frequencies are emitted to drive the LCC oscillator 24a to oscillate, and based on the one that reaches the maximum from the detected peak voltage itself, the resonance frequency of the LCC oscillator 24a is determined. The LCC oscillator 24a is controlled to oscillate at the resonance frequency obtained by the frequency sweep, and the susceptor 30 is inductively heated.

[0101] Naturally, during the frequency sweep process of the LCC oscillator 24a, the LCC oscillator 24a itself has a sinusoidal resonance with a duty ratio of 50%. Therefore, during the corresponding frequency sweep process, when the driving frequency is equal to or very close to the resonance frequency of the LCC oscillator 24a, the resonance voltage can be maximized. When the driving frequency deviates from the resonance frequency of the LCC oscillator 24a, the resonance voltage becomes smaller and smaller. Only when the driving frequency is equal to or very close to the resonance frequency, the LCC oscillator 24a resonates substantially completely, and in this case, the resonance voltage can be achieved. That is, there is an obvious corresponding relationship between the driving frequency and the resonance voltage when the driving frequency is higher than the resonance frequency.

[0102] For example, FIG. 15 shows a diagram of peak voltages detected when frequency sweeping is performed in descending order from 333 KHz to 200 KHz in one embodiment. During the frequency sweeping process, the peak voltage gradually increases and reaches its maximum up to the region of 217 KHz to 227 KHz. When the driving frequency continues to be lowered to 200 KHz, the peak voltage decreases. Under relatively relaxed or ambiguous accuracy requirements, the range of 217 KHz to 227 KHz is considered to be the resonance frequency range of the LCC oscillator 24a of this embodiment. According to the accuracy needs, in implementation, the user can select the width by themselves each time the frequency is adjusted by frequency sweeping. Naturally, the larger the width, the relatively lower the accuracy, but the frequency sweeping time can be shortened to increase the detection efficiency. On the other hand, the lower the width for each adjustment, the relatively higher the accuracy, but it takes time and the efficiency decreases. In an alternative embodiment, it is appropriate to perform frequency sweeping with an adjustment width of 1 to 30 KHz.

[0103] Naturally, if it is necessary to further improve the accuracy of the detected resonance frequency, the above frequency sweeping operation can be further continued between 217 KHz and 227 KHz at a frequency change rate of 0.5 KHz until the frequency of the maximum peak voltage, that is, a more accurate resonance frequency, is found.

[0104] Based on the above, another embodiment of this application further provides a frequency sweeping method for quickly searching for the resonance frequency by a variable step size algorithm. As shown in FIG. 16, the steps of this method include the following S1000, S2000, S3000, S4000, S5000, S5100, and S5200.

[0105] In S1000, start frequency sweeping from the set initial frequency value.

[0106] In S2000, drive the LCC oscillator 24a with the current sweeping frequency to oscillate.

[0107] In S3000, detect the peak voltage during the oscillation of the current LCC oscillator 24a, and calculate the difference value between the peak voltage and the previously detected peak voltage.

[0108] In S4000, it is determined whether the calculated difference value is a positive value. If it is a positive value, step S5000 is further executed. If it is not a positive value, it is determined that the current sweep frequency is the resonance frequency to be searched.

[0109] In S5000, it is determined whether the above difference value is greater than a predetermined value. If so, step S5100 is executed. If not, step S5200 is executed.

[0110] In S5100, the sweep frequency is decreased according to the first amplitude and the frequency sweep continues.

[0111] In S5200, the sweep frequency is decreased according to the second amplitude and the frequency sweep continues.

[0112] Here, the above first amplitude is larger than the second amplitude. For example, the first amplitude may be 5KHz / 10KHz / 15KHz / 20KHz / 22KHz / 25KHz / 30KHz, etc., and the second amplitude may be 0.5KHz / 1KHz / 1.5KHz / 2KHz / 5KHz, etc.

[0113] In the above embodiments, by using peak voltage detection and a high-speed search algorithm, in the frequency sweep process, based on the magnitude of the difference value between the current peak voltage and the previous peak voltage, the frequency decrease width is automatically adjusted. When the adjacent two detected peak voltages tend to be the same, the frequency decrease width of the sweep frequency becomes smaller and smaller. In the early stage, the time can be significantly shortened, and in the later stage, the accuracy can be significantly improved. Furthermore, it becomes possible to quickly and accurately capture the resonance frequency of the LCC oscillator 24a before initial heating.

[0114] In other modified embodiments, the process of the series LC oscillator and the LCC oscillator 24a is similar, and during the oscillation process, the voltage / current is also a sinusoidal or cosine resonance change curve with symmetry. Also, the efficiency of the series LC oscillator is maximum at resonance. Furthermore, according to the above frequency sweep and peak voltage detection methods, all can be used for the control of the aerosol generating device having a series LC oscillator.

[0115] It should be noted that although the preferred embodiments of the present application are shown in the specification and drawings of the present application, it is not limited to the embodiments described in this specification. Furthermore, those skilled in the art can make improvements or changes based on the above description, and all of these improvements and changes shall fall within the scope of protection of the claims appended to the present application.

Claims

1. An aerosol generating device configured to heat an aerosol generating product to generate an aerosol for smoking, comprising: a susceptor configured to be penetrated by a variable magnetic field and generate heat to heat the aerosol generating product; a parallel LC oscillator including an induction coil and a capacitor connected in parallel, the parallel LC oscillator being configured to guide a variable current through the induction coil to drive the induction coil to generate a variable magnetic field; a peak detection unit configured to detect the peak voltage of the parallel LC oscillator; a controller configured to drive and oscillate the parallel LC oscillator using a pulse of variable frequency, determine an optimum frequency of the parallel LC oscillator based on the peak voltage detected by the peak detection unit, and further control the parallel LC oscillator to guide the variable current based on the optimum frequency, and / or a controller configured to drive and oscillate the parallel LC oscillator using a pulse of variable duty ratio, determine an optimum duty ratio of the parallel LC oscillator based on the peak voltage detected by the peak detection unit, and further control the parallel LC oscillator to guide the variable current based on the optimum duty ratio.

2. The aerosol generating device according to claim 1, wherein the controller is configured to determine an optimum frequency of the parallel LC oscillator based on the peak voltage detected by the peak detection unit when the peak voltage is equal to or substantially close to a preset threshold voltage.

3. The aerosol generating device according to claim 1, wherein in the pulse of variable frequency, the frequency gradually varies in descending order.

4. The aerosol generating device according to claim 1, wherein the controller is configured to determine an optimum duty ratio of the parallel LC oscillator based on the peak voltage detected by the peak detection unit when the peak voltage is equal to or substantially close to a preset threshold voltage.

5. The aerosol generating device according to claim 1, wherein in the pulse of variable duty ratio, the duty ratio gradually varies in ascending order.

6. The aerosol generating device according to claim 1, wherein the variable duty ratio is greater than 50%.

7. The aerosol generating device according to claim 6, wherein the variable duty ratio is greater than 70%.

8. An aerosol generating device configured to heat an aerosol generating product to generate an aerosol for smoking, a susceptor configured to be penetrated by a variable magnetic field and generate heat to heat the aerosol generating product; an oscillator that is a series LC oscillator or a series LCC oscillator including an induction coil and a capacitor connected in series, and is configured to guide a variable current to flow through the induction coil to drive the induction coil to generate a variable magnetic field; a peak detection unit configured to detect the peak voltage of the oscillator; a controller configured to drive and oscillate the oscillator using a pulse whose frequency gradually varies, detect the peak voltage of the oscillator, calculate a difference value between the currently detected peak voltage and the previously detected peak voltage, determine whether the difference value is positive, if positive, decrease the frequency at which the oscillator is driven and oscillated, if not positive, determine that the previously detected peak voltage is the maximum value, determine the resonance frequency of the oscillator based on the maximum value of the peak voltage, drive and oscillate the oscillator according to the resonance frequency, and further generate a variable magnetic field in the induction coil.

9. The aerosol generating device according to claim 8, wherein in the pulse whose frequency gradually varies, the frequency gradually varies in descending order.

10. Reducing the frequency at which the oscillator is driven and oscillated includes determining whether the difference value is greater than a predetermined value, and if it is greater than the predetermined value, reducing the frequency at which the oscillator is driven and oscillated according to a first amplitude, and if it is not greater than the predetermined value, reducing the frequency at which the oscillator is driven and oscillated according to a second amplitude, wherein the first amplitude is greater than the second amplitude. The aerosol generating device according to claim 8.

11. An aerosol generating device configured to heat an aerosol generating product to generate an aerosol for smoking, a susceptor configured to be penetrated by a variable magnetic field and generate heat to heat the aerosol generating product; an oscillator including an induction coil and a capacitor, and is configured to guide a variable current to flow through the induction coil to drive the induction coil to generate a variable magnetic field, and a peak detection unit configured to detect the peak voltage of the oscillator; A controller configured to detect a peak voltage of the oscillator, determine an oscillation frequency of the oscillator based on the peak voltage, and adjust the oscillation frequency of the oscillator so that the oscillation frequency remains equal to or substantially close to a preset frequency, and an aerosol generating device including the same.

12. The peak detection unit The aerosol generating device according to any one of claims 1 to 11, including a holding capacitor configured to hold the peak voltage of the oscillator.

13. The peak detection unit An operational amplifier located between the holding capacitor and the oscillator, and further an operational amplifier configured to output the voltage of the oscillator to the holding capacitor, The aerosol generating device according to claim 12, including a voltage follower configured to output the peak voltage of the oscillator held by the holding capacitor.

14. The peak detection unit The aerosol generating device according to claim 13, further including a discharge switch configured to discharge the holding capacitor when turned on.

15. The sampling terminal of the operational amplifier is connected to the oscillator, The holding capacitor includes three paths, a first path of which is connected to the output terminal of the operational amplifier, a second path is connected to the discharge switch, and a third path is connected to the sampling terminal of the voltage follower. The aerosol generating device according to claim 14.

16. A susceptor configured to be penetrated by a variable magnetic field to generate heat and heat an aerosol generating product, An oscillator including an induction coil and a capacitor, the oscillator being configured to guide a variable current to flow through the induction coil and drive the induction coil to generate a variable magnetic field, and a control method for an aerosol generating device including the same, Detecting a peak voltage of the oscillator; Determining an oscillation frequency of the oscillator based on the peak voltage; and Adjusting the oscillation frequency of the oscillator so that the oscillation frequency remains equal to or substantially close to a preset frequency. The control method includes the above steps.

17. A susceptor configured to be penetrated by a variable magnetic field to generate heat and heat an aerosol generating product, A parallel LC oscillator including an inductive coil and a capacitor connected in parallel, the parallel LC oscillator configured to guide a varying current through the inductive coil to drive the inductive coil to generate a varying magnetic field, and a control method for an aerosol generating device including the parallel LC oscillator, driving and oscillating the parallel LC oscillator using a pulse whose frequency or duty ratio gradually varies, detecting a peak voltage of the parallel LC oscillator, comparing the peak voltage with a preset threshold voltage, and determining an optimum frequency or optimum duty ratio of the parallel LC oscillator when the peak voltage is equal to or substantially close to the preset threshold voltage, driving and oscillating the parallel LC oscillator according to the optimum frequency or optimum duty ratio, and further generating a varying magnetic field in the inductive coil, the control method including the steps.

18. The control method according to claim 17, wherein in the pulse whose frequency gradually varies, the frequency gradually varies in descending order.

19. a susceptor configured to be penetrated by a varying magnetic field to generate heat and heat an aerosol generating product, a series LC oscillator or a series LCC oscillator including an inductive coil and a capacitor connected in series, the series LC oscillator or the series LCC oscillator configured to guide a varying current through the inductive coil to drive the inductive coil to generate a varying magnetic field, and a control method for an aerosol generating device including the series LC oscillator or the series LCC oscillator, driving and oscillating the series LC oscillator or the series LCC oscillator using a pulse whose duty ratio is constant at 50% and whose frequency gradually varies, detecting a peak voltage of the series LC oscillator or the series LCC oscillator, calculating a difference value between the currently detected peak voltage and the previously detected peak voltage, determining whether the difference value is positive, when positive, decreasing the frequency at which the series LC oscillator or the series LCC oscillator is driven and oscillated, and when not positive, determining that the previously detected peak voltage is the maximum value, determining a resonance frequency of the series LC oscillator or the series LCC oscillator based on the maximum value of the peak voltage, driving and oscillating the series LC oscillator or the series LCC oscillator according to the resonance frequency, and further generating a varying magnetic field in the inductive coil, the control method including the steps.

20. The control method of the aerosol generator according to claim 19, wherein in the pulse whose frequency gradually varies, the frequency gradually varies in descending order of magnitude.

21. The step of reducing the frequency for driving and oscillating the series LC oscillator or the series LCC oscillator is to determine whether the difference value is greater than a predetermined value, and if it is greater than the predetermined value, to reduce the frequency for driving and oscillating the series LC oscillator or the series LCC oscillator according to the first amplitude, and if it is not greater than the predetermined value, to reduce the frequency for driving and oscillating the series LC oscillator or the series LCC oscillator according to the second amplitude, wherein the first amplitude is greater than the second amplitude, the control method of the aerosol generator according to claim 19.

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