Aerosol-generating device and system comprising an inductive heating device and method of operating same

Abstract

A method for controlling aerosol production in an aerosol-generating device is provided, the device including an inductive heating arrangement and a power source, the method including: performing, during a first heating phase, a calibration process for measuring calibration values associated with a susceptor inductively coupled to the arrangement; during a second heating phase, controlling power such that a temperature of the susceptor is adjusted based on the calibration values; and performing a pre-heating process, during the first heating phase and before the calibration process, the process including: controlling the power provided to cause an increase of susceptor temperature, monitoring a power source parameter based on current, and interrupting provision of power at a first predetermined value of the parameter, the first predetermined value being associated with a current value greater than a minimum operating current, and the first value of the parameter being determined during manufacture.

1 .- 15 . (canceled) 
     
     
         16 . A method for controlling aerosol production in an aerosol-generating device, the aerosol-generating device comprising an inductive heating arrangement and a power source configured to provide power to the inductive heating arrangement, the method comprising:
 performing, during a first heating phase during user operation of the aerosol-generating device for producing an aerosol, a calibration process for measuring one or more calibration values associated with a susceptor inductively coupled to the inductive heating arrangement, wherein the susceptor is configured to heat an aerosol-forming substrate;   during a second heating phase during user operation of the aerosol-generating device for producing an aerosol, controlling power provided to the inductive heating arrangement such that a temperature of the susceptor is adjusted based on the one or more calibration values; and   performing a pre-heating process, during the first heating phase, wherein the pre-heating process is performed before the calibration process, and wherein the pre-heating process comprises the steps of:
 i) controlling the power provided to the inductive heating arrangement to cause an increase of the temperature of the susceptor, 
 ii) monitoring a power source parameter, wherein the power source parameter is based at least in part on current, and 
 iii) interrupting provision of power to the inductive heating arrangement at a first predetermined value of the monitored power source parameter, wherein the first predetermined value of the monitored power source parameter is associated with a current value that is greater than a minimum operating current, and wherein the first predetermined value of the monitored power source parameter is determined during manufacture of the aerosol-generating device. 
   
     
     
         17 . The method according to  claim 16 , further comprising storing at least the first predetermined value of the monitored power source parameter in a memory of the aerosol-generating device. 
     
     
         18 . The method according to  claim 16 , wherein, subsequent to interrupting the provision of power to the inductive heating arrangement, the pre-heating process further comprises the steps of:
 iv) at a second predetermined value of the monitored power source parameter, controlling the power provided to the inductive heating arrangement to cause an increase of the temperature of the susceptor, wherein the second predetermined value of the monitored power source parameter is associated with a current value that is less than the minimum operating current, and   vi) repeating steps i) to iv) for a predetermined duration of the pre-heating process.   
     
     
         19 . The method according to  claim 18 , wherein the predetermined duration of the heating process is between 10 seconds and 15 seconds. 
     
     
         20 . The method according to  claim 18 , further comprising ceasing operation of the aerosol-generating device if the monitored power source parameter does not reach a value corresponding to the minimum operating current of the susceptor during the predetermined duration of the pre-heating process. 
     
     
         21 . The method according to  claim 16 , wherein the one or more calibration values comprise a power source parameter value corresponding to a minimum operating temperature of the susceptor. 
     
     
         22 . The method according to  claim 21 , wherein the one or more calibration values further comprise a power source parameter value corresponding to a maximum operating temperature of the susceptor. 
     
     
         23 . An aerosol-generating device, comprising:
 a power source configured to provide a DC supply voltage and a DC current; and   power supply electronics connected to the power source, the power supply electronics comprising:   a DC/AC converter,   an inductor connected to the DC/AC converter and being configured to generate an alternating magnetic field, when energized by an alternating current from the DC/AC converter, the inductor being couplable to a susceptor, wherein the susceptor is configured to heat an aerosol-forming substrate, and   a controller configured to:
 perform, during a first heating phase during user operation of the aerosol-generating device for producing an aerosol, a calibration process for measuring one or more calibration values associated with the susceptor, 
 during a second heating phase during user operation of the aerosol-generating device for producing an aerosol, control power provided to the inductor such that a temperature of the susceptor is adjusted based on the one or more calibration values, and 
 perform a pre-heating process, during the first heating phase, wherein the pre-heating process is performed before the calibration process, and
 wherein the pre-heating process comprises the steps of:
 i) controlling the power provided to the inductor to cause an increase of the temperature of the susceptor, 
 ii) monitoring a power source parameter, wherein the power source parameter is based at least in part on current, and 
 iii) interrupting provision of power to the inductor at a first predetermined value of the monitored power source parameter, wherein the first predetermined value of the monitored power source parameter is associated with a current value that is greater than a minimum operating current, and wherein the first predetermined value of the monitored power source parameter is determined during manufacture of the aerosol-generating device. 
 
 
   
     
     
         24 . The aerosol-generating device according to  claim 23 , wherein the monitored power source parameter is conductance or resistance. 
     
     
         25 . The aerosol-generating device according to  claim 23 ,
 wherein the monitoring the power source parameter comprises measuring a plurality of values of the power source parameter, and   wherein interrupting provision of power to the inductor at a first predetermined value of the monitored power source parameter comprises determining that a difference between consecutive values of the plurality of values is below a threshold difference.   
     
     
         26 . The aerosol-generating device according to  claim 23 , wherein, subsequent to interrupting the provision of power to the power supply electronics, the pre-heating process further comprises the steps of:
 iv) at a second predetermined value of the monitored power source parameter, controlling the power provided to the inductor to cause an increase of the temperature of the susceptor, wherein the second predetermined value of the monitored power source parameter corresponds to a susceptor temperature that is less than the minimum operating current, and   vi) repeating steps i) to iv) for a predetermined duration of the pre-heating process.   
     
     
         27 . The aerosol-generating device according to  claim 26 , wherein the predetermined duration of the heating process is between 10 seconds and 15 seconds. 
     
     
         28 . The aerosol-generating device according to  claim 26 , wherein if the monitored power source parameter does not reach a value corresponding to the minimum operating current of the susceptor during the predetermined duration of the pre-heating process, the controller is further configured to cease operation of the aerosol-generating device. 
     
     
         29 . The aerosol-generating device according to  claim 23 ,
 further comprising a cavity configured to receive an aerosol-generating article,   wherein the aerosol-generating article comprises the susceptor, and   wherein the controller is further configured to perform the pre-heating process in response to detecting the aerosol-generating article.   
     
     
         30 . An aerosol-generating system, comprising:
 the aerosol-generating device according to  claim 16 ; and   an aerosol-generating article comprising the aerosol-generating substrate and the susceptor.