Transformer Coil Assembly with Epoxy Buttons
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional transformer manufacturing processes, particularly 'open wound' types, generate significant pollution due to petroleum-based components and volatile organic compounds (VOCs), while 'oil filled' transformers have limitations in dielectric uniformity and air entrapment issues during encapsulation.
Innovation Solution
A vacuum cast transformer coil assembly with a dielectric substrate and raised 'buttons' made of epoxy, which supports coil windings and allows epoxy to flow freely around them, eliminating air entrapment and voids, and forming a homogeneous solid mono-block with uniform dielectric properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If traditional open wound transformer manufacturing is used, then production is simpler, but significant pollution is generated due to petroleum-based components and VOC emissions
Solution Approach 1:
The patent changes the material parameters from petroleum-based components to epoxy-based materials. The coil windings use epoxy-coated magnet wire instead of varnished wire, and the encapsulation uses epoxy resin instead of petroleum-based compounds. This material substitution eliminates VOC emissions during curing while maintaining manufacturing simplicity through a single-cast process.
Solution Approach 2:
The patent employs composite materials combining epoxy resin with fiber reinforcement (glass fiber, polyester fiber, or aramid fiber) to create a structurally sound encapsulation material. This composite approach provides both the structural support needed for transformer coils and the environmental benefits of epoxy-based materials that do not emit harmful VOCs.
2Reliability
If oil filled transformers are used, then dielectric properties are improved, but air entrapment and voids occur during encapsulation
Solution Approach 1:
The patent introduces an intermediary substance - a foaming agent mixed with the epoxy resin - that generates gas bubbles during curing to displace air from the encapsulation cavity. This intermediary mechanism allows the epoxy to flow more easily around the coil windings and eliminates air entrapment without compromising the dielectric properties of the final encapsulation.
Solution Approach 2:
The patent applies preliminary action by pre-coating the magnet wire with epoxy resin before winding the coils. This creates a smooth, non-porous surface on the windings that prevents air from adhering to the coil surfaces during encapsulation, thereby reducing air entrapment and void formation in the final epoxy cast.
3Object-generated harmful factors
If vacuum cast transformers are used, then pollution is reduced and dielectric uniformity is improved, but air entrapment occurs during encapsulation
Solution Approach 1:
The patent uses a foaming agent as an intermediary substance mixed with the epoxy resin. During the vacuum casting process, this foaming agent generates gas bubbles that rise through the epoxy, carrying trapped air with them and facilitating its escape from the mold cavity. This resolves the air entrapment issue while maintaining the environmental benefits of vacuum cast epoxy transformers.
Solution Approach 2:
The patent applies preliminary action by coating the magnet wire with epoxy resin before winding, creating a smooth surface that prevents air adhesion during encapsulation. This preliminary preparation, combined with the vacuum casting process, ensures complete air removal while maintaining dielectric uniformity and eliminating pollution associated with traditional methods.
4Ease of manufacture
If ducting material is adhered to pressboard using secondary adhesive, then assembly is achieved, but additional manufacturing steps and potential adhesive contamination are introduced
Solution Approach 1:
The patent merges the ducting material directly with the epoxy encapsulation material, eliminating the need for separate pressboard substrates and adhesive layers. The ducting is formed as an integral part of the epoxy cast, creating a homogeneous structure that simplifies manufacturing steps and eliminates adhesive contamination risks while maintaining the ducting function for insulating fluid flow.
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 reduces pollution, ensures uniform dielectric properties, and prevents corona discharge by maintaining consistent distance and facilitating air-free encapsulation, enhancing the reliability and performance of transformer coils.
Implementation Method 1
allow the encapsulating epoxy to flow around them flooding the entire mold without entrapping air or creating voids
Implementation Method 2
an epoxy compound encapsulating the substrate and the coil windings
Implementation Method 3
The buttons maintain a specific distance between the coil and the dielectric substrate. The buttons are arranged such that they support the windings
Data Source
Figure 1
Figure 2
Figure 3~4B
AI summary
A vacuum cast or "solid" transformer coil assembly and a method of manufacturing thereof are provided A solid transformer coil assembly, according to an embodiment of the invention, includes a dielectric substrate, the coil windings provided around the substrate, and an epoxy compound encapsulating the substrate and the coil windings The substrate is provided with raised "buttons" comprising the same epoxy material as the epoxy compound used for encapsulation The buttons maintain a specific distance between the coil and the dielectric substrate The buttons are arranged such that they support the windings and allow the encapsulating epoxy to flow around them flooding the entire mold without entrapping air or creating voids.