Motor Driving Device Board Segmentation for Noise Reduction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional motor-driving devices have a noise-vulnerable structure due to the intersection of power and signal flows, leading to interference and potential device malfunction and burnout, particularly due to high-frequency noise absorption by grounding wires.

Innovation Solution

The solution involves separating power and signal flow paths by positioning power-related and signal-related elements on distinct regions of the board assembly and using connectors or bolts for board coupling, eliminating wires and reducing assembly tolerance, while placing the DC link stage adjacent to the heat-dissipating means to improve temperature control and durability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If power and signal flows are separated into distinct regions on the board assembly, then electrical interference is minimized and reliability is improved, but device complexity increases due to the need for separate positioning and coupling structures

Engineering Contradiction:
Improveelectrical interference resistanceVSAvoidboard assembly structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The board assembly is divided into distinct power flow and signal flow regions, with power-related elements (rectifying section, inverter section, DC link) positioned in one region and signal-related elements (control board, sensing circuits) positioned in another region. This spatial segmentation prevents electrical interference between high-power and low-power circuits while maintaining functional integration within each region.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

A coupling structure (connector or bolt) is introduced as an intermediary element to join the power board and control board. This mediator enables electrical connection between the separated power and signal flows while maintaining physical separation, thus reducing interference without completely isolating the functional blocks.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Temperature

If grounding wires are used to connect the control board to the heat-dissipating means, then heat dissipation is improved, but high-frequency noise is absorbed and device malfunction may occur

Engineering Contradiction:
Improveheat dissipation performanceVSAvoidnoise vulnerability
Core Design Contradiction:
TemperatureVSReliability

Solution Approach 1:

The grounding wire connection between the control board and heat-dissipating means is removed entirely. Instead, the control board is coupled to the power board through a dedicated coupling structure that provides electrical connection without creating a noise-vulnerable path to the heat-dissipating means. This extraction eliminates the harmful noise absorption effect while maintaining necessary electrical connections.

Inventive Principle:
Principle #2Taking out (Extraction)

3Ease of manufacture

If wires are used for board coupling, then electrical connections are established, but assembly tolerance increases and production efficiency decreases

Engineering Contradiction:
Improveassembly efficiencyVSAvoidassembly tolerance
Core Design Contradiction:
Ease of manufactureVSManufacturing precision

Solution Approach 1:

Wire-based electrical connections are replaced with a rigid coupling structure (connector or bolt) that directly joins the power board and control board. This mechanical substitution eliminates the need for flexible wires, reduces the number of assembly steps, and provides more precise and stable electrical connections with reduced tolerance requirements.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

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 minimizes electrical interference, enhances heat-dissipating performance, improves assembly efficiency, and allows for device miniaturization, thereby improving durability and space utilization.

Implementation Method 1

heat-dissipating means 20 disposed below the base 10

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 2

heat-dissipating means 20 disposed below the base 10

Methodology Applied
Scientific EffectConvection: Convection

Data Source

PatentEP3565393B1Device for driving motor
Publication Date: 2021.04.07 LSIS CO LTD
  • EP3565393B1 patent drawingFigure 1
  • EP3565393B1 patent drawingFigure 2
  • EP3565393B1 patent drawingFigure 3

AI summary

A motor-driving device includes a middle base; a first board disposed above the middle base; power-related components disposed on the first board and in a first region thereof, wherein the power-related components include a power input terminal, a rectifying module, an initial charging circuit, an inverting module, and an output terminal block; signal-related components disposed on the first board and in a second region thereof opposite to the first region, wherein the signal-related components include a switching mode power supply (SMPS), a gate drive circuit, and a sensing and protection circuit; a second board electrically connected to the first board; a direct-current (DC) link stage mounted on the second board, wherein the DC link stage is configured for storing power from the initial charging circuit and for supplying the power to the inverting module or the SMPS; and a third board electrically connected to the first board , wherein the third board is configured for receiving a sign DC link stage DC link stage al from the gate drive circuit, and the sensing and protection circuit.