Steering Wheel Heating Voltage Control for EMC and Cable Flexibility
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing steering wheel heating devices for motor vehicles are limited in their ability to efficiently deliver power while maintaining flexibility and electromagnetic compatibility, as they often require high current levels and rapid pulse width modulation, which can lead to increased structural requirements and electromagnetic interference.
Innovation Solution
A steering wheel heating device with a controllable DC-DC converter that adjusts output voltage to control temperature, allowing for reduced line cross-sections and the use of pulse width modulation, enabling precise temperature control over a wide range without unnecessary high frequencies or shielding.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If a DC-DC converter with constant output voltage (e.g., 48V) is used, then the current intensity is reduced for a given heating power, but the temperature control precision deteriorates and requires rapid pulse width modulation
Solution Approach 1:
The patent applies parameter changes by making the DC-DC converter output voltage controllable rather than constant. The control unit adjusts the output voltage of the DC-DC converter dynamically based on the desired temperature setpoint, allowing precise power regulation without requiring rapid pulse width modulation. This resolves the contradiction by changing the voltage parameter from fixed to variable, enabling both efficient power delivery and precise temperature control.
2Measurement precision
If rapid pulse width modulation is used for temperature control, then the temperature control precision is improved, but electromagnetic interference increases and requires additional shielding
Solution Approach 1:
The patent converts the potential harm of electromagnetic interference from rapid pulse width modulation into a benefit by using the controllable DC-DC converter output voltage instead. By regulating temperature through output voltage adjustment rather than rapid switching, the system achieves precise temperature control without generating harmful electromagnetic interference, eliminating the need for additional shielding elements.
3Power
If high current levels are used for heating, then the heating power is sufficient, but the cable cross-sections must be larger and flexibility is reduced
Solution Approach 1:
The patent applies dynamics by making the DC-DC converter output voltage adjustable rather than fixed. By dynamically controlling the output voltage to match the desired temperature setpoint, the system delivers appropriate heating power without requiring consistently high current levels, thereby maintaining cable flexibility while ensuring sufficient heating capability when needed.
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
The solution allows for efficient power delivery to the steering wheel with reduced cable cross-sections, improved electromagnetic compatibility, and precise temperature control, enabling faster heating and extended temperature range without overloading the winding tapes.
Implementation Method 1
an electrical circuit output (4) for connecting a heating element (3) for heating the steering wheel (2)
Data Source
Figure 1~3
AI summary
The device (1) has an electrical circuitry input unit (11) attached to an electrical voltage source (12) of a motor car. An electrical circuitry output unit (4) attaches a heating element (3) for heating a steering wheel (2). An electronic control unit (8) adjusts temperature of the steering wheel on predeterminable reference value (Tsoll). Switched DC static converters (7) comprise a control terminal (71) that is coupled with a control unit (8). The control unit adjusts temperature of the steering wheel by controlling voltage level of the output voltage by the static converters. An independent claim is also included for a method for operating a heating device.