Integrated Inverter Driver Modules for Electric Motors

Solution Overview

Problem

Existing electric motor systems face issues with parasitic impedance in electrical cables, leading to power loss, high-voltage transients, and electromagnetic interference, which are typically addressed by oversizing components or reducing switching frequencies, resulting in increased size, cost, and reduced reaction time.

Innovation Solution

The integration of driver modules directly connected to stator windings without significant parasitic impedance, using inverter circuits with silicon-carbide transistors, snubber circuits, and capacitance circuits to reduce unwanted wave effects and enhance efficiency, allowing the driver module to act as a filter and improve motor performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If electrical cables are used to connect driver circuitry to stator windings, then the system is easier to manufacture and assemble, but parasitic impedance causes power loss, high-voltage transients, and electromagnetic interference

Engineering Contradiction:

Improvepower lossVSAvoidcable connections

Core Design Contradiction:

Loss of energyVSDevice complexity

Solution Approach 1:

The driver module is merged with the stator winding assembly by mounting the driver module directly on the stator core or stator housing in immediate proximity to the stator winding. This integration eliminates or minimizes electrical cable connections, thereby reducing parasitic impedance and associated power losses while maintaining manufacturing feasibility through modular assembly procedures

Inventive Principle:

Principle #5Merging (Combining)

2Loss of energy

If cable length is reduced to minimize parasitic impedance, then power loss and electromagnetic interference are reduced, but manufacturing and assembly become more difficult

Engineering Contradiction:

Improvepower lossVSAvoidassembly

Core Design Contradiction:

Loss of energyVSEase of manufacture

Solution Approach 1:

The driver module is merged with the stator winding assembly by mounting the driver module directly on the stator core or stator housing in immediate proximity to the stator winding. This integration eliminates or minimizes electrical cable connections, thereby reducing parasitic impedance and associated power losses while maintaining manufacturing feasibility through modular assembly procedures

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

A printed circuit board serves as an intermediary substrate that mounts the driver module components and provides electrical connections to the stator winding terminals. This PCB intermediary consolidates multiple connection points into a single integrated component that can be easily mounted to the stator, simplifying assembly while maintaining short electrical path lengths

Inventive Principle:

Principle #24Intermediary (Mediator)

3Object-affected harmful factors

If switching frequency is reduced to minimize wave effects, then electromagnetic interference is reduced, but reaction time and performance decrease

Engineering Contradiction:

Improveelectromagnetic interferenceVSAvoidreaction time

Core Design Contradiction:

Object-affected harmful factorsVSProductivity

Solution Approach 1:

The driver module incorporates snubber circuits that convert harmful high-voltage transients and electromagnetic interference into manageable energy dissipation through controlled resistance elements. This allows the system to operate at high switching frequencies for improved reaction time while the snubber circuits suppress the harmful wave effects that would otherwise result

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

4Reliability

If components are oversized to compensate for parasitic impedance effects, then reliability is improved, but device size and cost increase

Engineering Contradiction:

Improvesystem reliabilityVSAvoidmotor size

Core Design Contradiction:

ReliabilityVSVolume of moving object

Solution Approach 1:

The driver module is merged with the stator winding assembly by mounting the driver module directly on the stator core or stator housing in immediate proximity to the stator winding. This integration eliminates or minimizes electrical cable connections, thereby reducing parasitic impedance and associated power losses while maintaining manufacturing feasibility through modular assembly procedures

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The system operates at optimized switching frequencies and voltage levels that account for the minimized parasitic impedance of the integrated driver module. By changing these operating parameters and eliminating cable-induced impedance, the system achieves reliable operation without requiring oversized components, thereby maintaining compact motor dimensions

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

This configuration significantly reduces unwanted wave effects, enables miniaturization, and increases the efficiency and performance of electric motors by eliminating major sources of parasitic impedance and allowing direct impedance matching, resulting in a more compact and cost-effective design.

Implementation Method 1

driver circuitry coupled to the plurality of stator windings for creating a rotating magnetic field for driving the rotor

Methodology Applied

Scientific EffectElectromagnetic induction: Electromagnetic Induction

Implementation Method 2

The integration of driver modules directly connected to stator windings without significant parasitic impedance, using inverter circuits with silicon-carbide transistors

Methodology Applied

Scientific EffectSemiconductor switching:

Implementation Method 3

snubber circuits, and capacitance circuits to reduce unwanted wave effects

Methodology Applied

Scientific EffectEnergy dissipation:

Implementation Method 4

capacitance circuits to reduce unwanted wave effects and enhance efficiency

Methodology Applied

Scientific EffectCapacitance filtering: Capacitance

Data Source

PatentUS11689084B2Electromotor having integrated inverter

Publication Date: 2023.06.27 FECREATE AS

AI summary

An electric motor has a stator and a rotor for rotation relative to the stator. The stator has a plurality of stator windings distributed along the circumference of the stator. Each stator winding is connected to a respective end terminal. Driver circuitry is coupled to the plurality of stator windings for creating a rotating magnetic field for driving the rotor. The driver circuitry has one driver module per stator winding. Each driver module is mounted close to its respective stator winding. Each driver module is connected to the respective end terminal of its respective stator winding without a parasitic impedance of any significance being present in between said driver module and said stator winding.