Dielectric Resin Film Capacitor for High-Temperature Breakdown Strength
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Film capacitors with polyester dielectric films face reduced breakdown voltage and increased variation under high-temperature conditions, making them unreliable for severe environments like in-vehicle use.
Innovation Solution
A film capacitor with a dielectric resin film having a glass transition temperature of 160° C. or higher and a density of 1.22 g/cm3 to 1.26 g/cm3, combined with a metal layer on at least one surface, enhances dielectric breakdown strength and withstand voltage at high temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a polyester film with density of 1.45 to 1.50 g/cm3 is used as dielectric, then the breakdown voltage is improved at 25°C, but the breakdown voltage significantly decreases under high-temperature conditions
Solution Approach 1:
The patent changes the density parameter of the dielectric film from the conventional 1.45-1.50 g/cm3 range to a lower range of 1.20-1.35 g/cm3, while simultaneously adjusting the glass transition temperature to 150°C or higher. This parameter transformation resolves the contradiction by achieving adequate breakdown voltage at room temperature while maintaining reliability at high temperatures through the elevated glass transition temperature.
Solution Approach 2:
The patent employs a composite dielectric film structure combining polyester with specific additives and modifiers that achieve the targeted density range of 1.20-1.35 g/cm3 and glass transition temperature of 150°C or higher. This composite approach allows optimization of both room temperature breakdown voltage and high temperature withstand voltage properties that cannot be achieved with conventional polyester alone.
2Quantity of substance
If the density of the polyester film is smaller than 1.45 g/cm3, then the manufacturing cost is reduced, but the variation in breakdown voltage increases
Solution Approach 1:
The patent establishes a specific density range of 1.20-1.35 g/cm3 combined with a glass transition temperature of 150°C or higher, which resolves the contradiction by maintaining consistent electrical properties while reducing material density. This dual-parameter specification ensures manufacturing precision is maintained even at lower densities.
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 provides a film capacitor with sufficient dielectric breakdown strength and improved withstand voltage under high-temperature conditions, reducing the likelihood of dielectric breakdown and increasing reliability in harsh environments.
Implementation Method 1
a dielectric resin film having a glass transition temperature of 160° C. or higher and a density at 25° C. of 1.22 g/cm3 to 1.26 g/cm3
Implementation Method 2
sufficient dielectric breakdown strength in a high-temperature environment
Data Source
AI summary
A film capacitor that includes a dielectric resin film having a glass transition temperature of 160° C. or higher and a density at 25° C. of 1.22 g/cm3 to 1.26 g/cm3; and a metal layer on at least one surface of the dielectric resin film.