Embedded Power Inductor Temperature Sensing Against Liquid Interference

Solution Overview

Problem

Conventional power inductors, particularly those used in variable voltage converters, face challenges in accurately measuring temperature due to external interference from liquids, which can affect the reliability and efficiency of electric vehicle and hybrid electric vehicle systems.

Innovation Solution

The proposed solution involves a power inductor design with a thermal sensor embedded between the magnetic core and the electrically conductive winding, protected by a sensor-enclosure within the fixture, allowing for more accurate temperature monitoring and reduced susceptibility to external interference.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a thermal sensor is placed on the exterior of the power inductor, then the device complexity is reduced, but the measurement precision deteriorates due to external interference from liquids

Engineering Contradiction:

Improvetemperature measurement accuracyVSAvoidsensor enclosure structure

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The thermal sensor is nested within a sensor enclosure that is integrated into the power inductor structure. The enclosure contains the sensor while maintaining thermal contact with the magnetic core, allowing the sensor to measure core temperature directly without being exposed to external liquid interference. This nested configuration protects the sensor while preserving its measurement function.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The sensor enclosure acts as an intermediary between the thermal sensor and the external environment. It provides a protected interface that allows thermal conduction from the magnetic core to the sensor while blocking direct contact between the sensor and external liquids, thus eliminating measurement interference.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Measurement precision

If a thermal sensor is embedded between the magnetic core and the electrically conductive winding, then the measurement precision improves, but the device complexity increases due to the sensor enclosure structure

Engineering Contradiction:

Improvetemperature measurement accuracyVSAvoidexternal interference from liquids

Core Design Contradiction:

Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The thermal sensor is nested within a sensor enclosure that is integrated into the power inductor structure. The enclosure contains the sensor while maintaining thermal contact with the magnetic core, allowing the sensor to measure core temperature directly without being exposed to external liquid interference. This nested configuration protects the sensor while preserving its measurement function.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The sensor enclosure acts as an intermediary between the thermal sensor and the external environment. It provides a protected interface that allows thermal conduction from the magnetic core to the sensor while blocking direct contact between the sensor and external liquids, thus eliminating measurement interference.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Measurement precision

If the thermal sensor is disposed between the magnetic core and the electrically conductive winding, then the measurement precision improves, but the ease of manufacture deteriorates

Engineering Contradiction:

Improvetemperature measurement accuracyVSAvoidassembly process complexity

Core Design Contradiction:

Measurement precisionVSEase of manufacture

Solution Approach 1:

The sensor enclosure is pre-integrated into the fixture structure before the winding process. The thermal sensor is positioned within the enclosure, and the entire assembly is prepared in advance, allowing for streamlined assembly during manufacturing. This preliminary preparation reduces assembly complexity despite the embedded sensor configuration.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The sensor enclosure is merged with the fixture structure, creating an integrated component rather than separate parts. This consolidation reduces the number of discrete components and assembly steps, making the manufacturing process more efficient despite the embedded sensor requirement.

Inventive Principle:

Principle #5Merging (Combining)

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 design enhances temperature measurement accuracy and reliability, reducing the impact of external interference and optimizing the efficiency of power inductors in high-power applications, such as electric vehicles.

Implementation Method 1

The thermal sensor is disposed in a sensor-enclosure that is part of the fixture such that the thermal sensor is disposed between the magnetic core and the electrically conductive winding

Methodology Applied

Scientific EffectThermal conduction: Conduction (thermal)

Data Source

PatentUS12211639B2Embedded temperature sensor solution for power inductor

Publication Date: 2025.01.28 FORD GLOBAL TECH LLC

AI summary

A power inductor such as a variable voltage converter power inductor having a temperature sensor embedded therein is disclosed. In one or more embodiments, the sensor may be disposed between the core and the coil or winding. The sensor may be positioned in the cavity of a bobbin or the core itself.