Induction Hob Coil Frequency Control for Even Heating
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing induction hobs face inefficiencies at high power densities, particularly when only a few induction heating coils are covered by a cooking vessel, leading to energy wastage and uneven heating.
Innovation Solution
The method involves activating induction heating coils that are partially covered by the cooking vessel at the same power level to ensure even heating, and increasing the frequency of the least overlapped coils to reduce current and losses, while operating all coils in a network to distribute power evenly across the cooking vessel's surface.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If fewer induction heating coils are operated at very high power density to achieve high heating power, then heating power is improved, but energy efficiency deteriorates when coils are not fully covered
Solution Approach 1:
The system segments the induction heating coils into different operational groups: fully covered coils operate at maximum power density for high heating output, while partially covered coils operate at reduced power density or are switched off to minimize energy waste. This segmentation allows the system to optimize the balance between heating power and energy efficiency by treating different coil regions differently based on their coverage status.
2Productivity
If induction heating coils are operated at different power densities to optimize local heating, then heating effectiveness is improved, but heating uniformity deteriorates
Solution Approach 1:
The system applies local quality by assigning different power densities to different coil groups based on their coverage by the cooking vessel. Fully covered coils receive maximum power for intensive heating, while partially covered coils receive reduced power. The control system continuously monitors coverage and adjusts power distribution locally, ensuring that each region receives appropriate heating intensity while maintaining overall heating uniformity through coordinated control.
3Loss of energy
If induction heating coils are switched off to save energy when not fully covered, then energy efficiency is improved, but heating uniformity deteriorates
Solution Approach 1:
The system employs dynamic control by continuously monitoring the coverage status of each induction heating coil and adjusting its operational state in real-time. When a coil is fully covered, it operates at maximum power; when partially covered, it transitions to reduced power mode; and when insufficiently covered, it is switched off. This dynamic adaptation allows the system to optimize energy efficiency at each moment while maintaining heating uniformity through coordinated adjustment of multiple coils.
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 enhances energy efficiency and achieves more even heating, allowing for quicker boiling and improved heat distribution, reducing energy consumption and noise interference.
Implementation Method 1
an induction cooktop with a cooktop surface and, below it, a number of induction heating coils
Implementation Method 2
The induction heating coils that are at least partially covered by the cooking zone are controlled together to heat the entire vessel
Data Source
Figure 1
AI summary
To control an induction cooktop with a cooking zone and several induction heating coils underneath, each of which can be controlled individually or collectively, a cookware placed on the cooktop defines a cooking zone. Those induction heating coils that are at least partially covered by the cooktop are controlled collectively to heat the cookware. In a first operating mode, defined as operation with a very high power density, the control frequency is increased for at least the induction heating coil in the collective that has the least coverage by the cooktop. This induction heating coil thus operates at a higher frequency than other induction heating coils or than the remaining induction heating coils under this cooktop.