Rotating Machine Rotor Winding with Rectangular and Circular Sections

Solution Overview

Problem

Current rotor designs for rotating electrical machines, such as alternators, face challenges in achieving optimal electrical performance, heat management, and simplifying design while maintaining conventional connections and potentially dispensing with magnets.

Innovation Solution

The rotor features a winding with a first portion having a rectangular cross-section with flats and a second portion with a circular cross-section, allowing for efficient filling and connection, reducing air gaps, and enabling the use of conventional stripping processes, with a guide member for electrical connection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a wire of rectangular cross-section is used for the winding, then the filling rate and electrical performance are improved, but the connection to conventional collectors becomes difficult

Engineering Contradiction:

Improvefilling rateVSAvoidconnection ease

Core Design Contradiction:

ProductivityVSEase of manufacture

Solution Approach 1:

The wire is divided into two distinct portions: a first portion with rectangular cross-section for the winding turns, and a second portion with circular cross-section for the connection to the collector. This segmentation allows each portion to be optimized for its specific function while maintaining overall manufacturability.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different sections of the wire have different cross-sectional shapes tailored to their local requirements: rectangular section where high filling rate is needed (winding turns) and circular section where conventional connection is needed (collector connection). This local differentiation resolves the contradiction between optimization and compatibility.

Inventive Principle:

Principle #3Local quality

2Ease of manufacture

If a wire of circular cross-section is used for the winding, then the connection to collectors is simplified, but the filling rate and electrical performance deteriorate

Engineering Contradiction:

Improveconnection easeVSAvoidfilling rate

Core Design Contradiction:

Ease of manufactureVSProductivity

Solution Approach 1:

The wire is divided into two distinct portions: a first portion with rectangular cross-section for the winding turns, and a second portion with circular cross-section for the connection to the collector. This segmentation allows each portion to be optimized for its specific function while maintaining overall manufacturability.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different sections of the wire have different cross-sectional shapes tailored to their local requirements: rectangular section where high filling rate is needed (winding turns) and circular section where conventional connection is needed (collector connection). This local differentiation resolves the contradiction between optimization and compatibility.

Inventive Principle:

Principle #3Local quality

3Temperature

If air space between turns is increased, then the heat management is simplified, but the electrical performance and filling rate deteriorate

Engineering Contradiction:

Improveheat managementVSAvoidelectrical performance

Core Design Contradiction:

TemperatureVSProductivity

Solution Approach 1:

The rectangular cross-section of the wire with its flat surfaces allows turns to pack tightly together with minimal air gaps, maximizing the filling rate and electrical performance while the flats facilitate heat conduction paths between adjacent turns.

Inventive Principle:

Principle #14Spheroidality (Curvature)

Data Source

PatentEP3005533B1Electrical rotating machine for motor vehicle

Publication Date: 2022.11.09 VALEO EQUIP ELECTRIC MOTEUR

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AI summary

The invention relates to a rotor (2), especially for an electrical rotating machine, for example for an alternator, comprising an electric winding (100) formed by at least one electric wire (101), said wire comprising: at least one first portion (104) wound as at least one turn of the winding; a transverse section with at least one flat (115) along said first portion; at least one second portion (105) allowing the connection of the winding to an electric circuit; and an essentially circular transverse section along said second portion.