SMA-Actuated Enclosure Venting for Passive Electrical Cooling

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing low and medium voltage electrical enclosures face issues with temperature variations leading to performance decay, service interruptions, and electromagnetic compatibility problems due to cooling systems requiring cabling, maintenance, and additional certifications.

Innovation Solution

A low and medium voltage electrical enclosure with temperature-sensitive covers actuated by Shape Memory Alloy (SMA)-based actuators that open and close venting openings based on temperature changes, eliminating the need for dedicated cabling, power feed, and maintenance, while maintaining electromagnetic compatibility.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If forced air ventilation cooling system is used, then temperature control is improved, but device complexity and maintenance requirements increase due to cabling and power feed requirements

Engineering Contradiction:
Improvetemperature controlVSAvoidcabling system
Core Design Contradiction:
TemperatureVSDevice complexity

Solution Approach 1:

The patent extracts the cooling function from the electrical enclosure by providing separate venting openings in the external walls that allow air circulation outside the enclosure, eliminating the need for internal cooling equipment, cabling, and power feed systems while maintaining effective temperature control

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The cooling system operates autonomously using natural convective air circulation driven by temperature differences between the enclosure interior and exterior environments, eliminating the need for external power sources, control systems, and maintenance interventions

Inventive Principle:
Principle #25Self-service

2Temperature

If cooling system with electrical equipment is added, then temperature control is improved, but electromagnetic compatibility problems arise requiring additional tests and certifications

Engineering Contradiction:
Improvetemperature controlVSAvoidelectromagnetic compatibility
Core Design Contradiction:
TemperatureVSObject-affected harmful factors

Solution Approach 1:

The patent removes all electrical cooling equipment from the enclosure by implementing passive convective cooling through venting openings, thereby eliminating electromagnetic interference sources and the associated certification requirements while maintaining effective temperature management

Inventive Principle:
Principle #2Taking out (Extraction)

3Extent of automation

If Shape Memory Alloy actuators are used, then automation is improved, but manufacturing complexity increases

Engineering Contradiction:
Improveautomatic cover actuationVSAvoidmanufacturing complexity
Core Design Contradiction:
Extent of automationVSEase of manufacture

Solution Approach 1:

The patent utilizes the temperature-dependent dimensional change property of Shape Memory Alloy actuators to automatically actuate covers in response to temperature variations, achieving intelligent automation while maintaining relatively simple manufacturing through the use of commercially available SMA components

Inventive Principle:
Principle #35Parameter changes

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 SMA-based actuation system effectively controls temperature variations, ensuring reliable operation without additional components, reducing maintenance needs, and eliminating the need for EMC tests and certifications, while providing efficient convective air circulation.

Implementation Method 1

The actuating device (40) comprises an actuating mechanism (41) having a Shape Memory Alloy-based (SMA-based) actuating element (42) having a first dimension at said first predetermined temperatures reversibly changeable into a second dimension at second predetermined temperatures

Methodology Applied
Scientific EffectShape Memory Alloy: Shape Memory Alloy

Implementation Method 2

under very specific and predetermined temperature conditions the covers closing the one or more openings in the external and/or internal walls of the enclosure may be open, thereby creating a convective air circulation inside the enclosure

Methodology Applied
Scientific EffectConvection: Convection

Data Source

PatentEP3813208B1Low and medium voltage electrical enclosure with shape memory alloy-based cooling system
Publication Date: 2025.07.02 ABB SPA
  • EP3813208B1 patent drawingFigure 1
  • EP3813208B1 patent drawingFigure 2a~2b
  • EP3813208B1 patent drawingFigure 3

AI summary

A low and medium voltage electrical enclosure comprising a supporting structure which defines an internal space delimited by walls forming one or more compartments housing one or more electrical apparatuses. At least one of said walls is provided with one or more venting openings that put into communication said internal space with the outside of said low voltage electrical enclosure and/or one of said compartments with a second compartment. The venting openings are provided with a cover closing a corresponding venting opening in a first - closed - operating condition at first predetermined temperatures and the enclosure is provided with an actuating device adapted to open said cover in a second - open - operating condition at second predetermined temperatures. The actuating device comprises an actuating mechanism having a Shape Memory Alloy-based (SMA-based) actuating element having a first dimension at said first predetermined temperatures reversibly changeable into a second dimension at said second predetermined temperatures, the reversible change of dimension of said SMA-based actuating element from said first dimension to said second dimension determining the reversible movement of said cover from said first - closed -operating condition to said second - open - operating condition, and vice-versa.