Susceptor Pulse Duty Control for Puff Cooling Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In aerosol-generating systems with inductive heating arrangements, there is a risk of overheating during cooling events such as user puffs, due to changes in the relationship between susceptor conductance and temperature.
Innovation Solution
A method of controlling the inductive heating arrangement by providing pulses of electrical current to maintain a target conductance or resistance, detecting cooling events, determining a maximum duty cycle limit, and increasing the duty cycle of the pulses within this limit to compensate for cooling events and prevent overheating.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If apparent resistance or conductance is used to monitor susceptor temperature, then temperature monitoring is achieved without direct electrical connection or dedicated temperature sensor, but the relationship between apparent resistance/conductance and temperature may change during cooling events leading to overheating risk
Solution Approach 1:
The system continuously monitors apparent conductance and uses this feedback to adjust the duty cycle of heating pulses in real-time. During cooling events, the controller detects changes in conductance-temperature relationship and dynamically adjusts power delivery to maintain safe operating temperatures, preventing overheating while adapting to varying thermal conditions.
Solution Approach 2:
The system changes the operational parameters by adjusting the duty cycle of heating pulses based on detected cooling events. When a cooling event is detected (indicated by abnormal conductance changes), the controller modifies the heating parameters to compensate for the altered conductance-temperature relationship, ensuring reliable temperature control despite the changing conditions.
2Productivity
If duty cycle is increased to compensate for cooling events, then optimal aerosol generation is maintained, but the risk of overheating increases if the duty cycle exceeds maximum limits
Solution Approach 1:
The system dynamically adjusts the duty cycle within safe operational boundaries. Rather than using a fixed duty cycle, the controller continuously adapts the heating power based on real-time conductance monitoring, allowing the duty cycle to vary between minimum and maximum limits to maintain optimal aerosol generation while preventing overheating during cooling events.
Solution Approach 2:
The closed-loop control system uses apparent conductance feedback to regulate duty cycle adjustments. When cooling events are detected, the system increases duty cycle to maintain aerosol generation, but the feedback mechanism ensures the duty cycle remains within maximum limits to prevent the susceptor temperature from exceeding safe operating thresholds.
3Productivity
If more power is provided to the inductor to counteract cooling effect during user puff, then optimal aerosol generation is maintained, but the possibility of overheating increases
Solution Approach 1:
The system uses real-time monitoring of apparent conductance to provide feedback on actual thermal conditions. This feedback enables the controller to precisely modulate power delivery, increasing power only when and where needed to counteract cooling effects while maintaining temperature within safe limits, thereby preventing overheating while sustaining aerosol generation during user puffs.
Solution Approach 2:
The system applies partial compensation for cooling events by adjusting the duty cycle within defined limits rather than providing full compensation. This partial action approach is sufficient to maintain optimal aerosol generation during cooling events while deliberately limiting the compensation to prevent excessive power delivery and associated overheating risks.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach effectively reduces the risk of overheating during cooling events by dynamically adjusting the power supply to the inductive heating arrangement, ensuring optimal aerosol generation and delivery.
Implementation Method 1
The inductor generates an alternating magnetic field that causes heating in the susceptor
Implementation Method 2
inductive heating arrangement that comprises an inductor and a susceptor, the susceptor coupled to the inductor so that the provision of an alternating electrical current to the inductor causes heating of the susceptor
Implementation Method 3
heat is transferred from the susceptor to the aerosol-forming substrate primarily by conduction
Implementation Method 4
The vapour cools in the airflow to generate the aerosol
Data Source
AI summary
A method of controlling an inductive heating arrangement is provided, the arrangement including an inductor and a susceptor coupled to the inductor so that provision of an alternating electrical current to the inductor causes heating of the susceptor, the method including providing pulses of electrical current to the inductor to maintain a conductance or resistance associated with the susceptor at a target conductance or resistance; detecting a cooling event associated with the susceptor; determining a maximum duty cycle limit for the pulses of electrical current for a duration of the cooling event; and increasing a duty cycle of the pulses of electrical current for the duration of the detected cooling event, to compensate for the detected cooling event, to a duty cycle at or below a maximum duty cycle limit.