EtherCAT Double-Ring Switching for Fault-Tolerant Telegram Return

Solution Overview

Problem

Automation networks with EtherCAT protocol face limitations in maintaining communication between the master and slave participants when network distributors or switches are introduced, especially in error modes due to line faults, leading to unreliable data transmission and real-time capability issues.

Innovation Solution

A redundant double ring structure is implemented with switching devices and network distributors, allowing telegrams to be transmitted and received through multiple paths, ensuring continuous communication and reliability even in error modes by using a first and second master communication path and first and second slave communication paths, and incorporating error handling mechanisms to adapt to line faults.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a redundant data line network is implemented to maintain communication in error mode, then reliability is improved, but device complexity increases

Engineering Contradiction:

Improvecommunication reliabilityVSAvoidnetwork structure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The network is segmented into two independent ring structures: a first double ring structure for master participant communication and a second double ring structure for slave participant communication. This segmentation allows independent error handling in each ring, maintaining reliability while managing complexity through modular design.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Switching devices are introduced as intermediary components that intelligently route telegrams through available paths. The switching devices detect line faults and dynamically redirect communication flows, acting as mediators that maintain reliability without requiring complex configuration at each network participant.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Adaptability or versatility

If network distributors or switches are introduced to expand the automation network, then adaptability is improved, but communication reliability in error mode deteriorates

Engineering Contradiction:

Improvenetwork expandabilityVSAvoidcommunication reliability

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The network is segmented into two independent ring structures: a first double ring structure for master participant communication and a second double ring structure for slave participant communication. This segmentation allows independent error handling in each ring, maintaining reliability while managing complexity through modular design.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The network dynamically adapts to errors through automatic path switching. When a line fault is detected in either ring, the system dynamically redirects telegrams through alternative paths within the same ring structure, maintaining communication reliability while preserving network expandability.

Inventive Principle:

Principle #15Dynamics

3Productivity

If telegrams are transmitted through all slave participants in sequence, then real-time control is achieved, but loss of time increases due to error mode limitations

Engineering Contradiction:

Improvereal-time control capabilityVSAvoidcommunication delay

Core Design Contradiction:

ProductivityVSLoss of time

Solution Approach 1:

The network is segmented into two independent ring structures: a first double ring structure for master participant communication and a second double ring structure for slave participant communication. This segmentation allows independent error handling in each ring, maintaining reliability while managing complexity through modular design.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The dual-ring structure ensures continuous telegram transmission by providing alternative paths. When a line fault occurs, telegrams continue to circulate through the intact ring structure, maintaining real-time control capability without interruption or significant delay.

Inventive Principle:

Principle #20Continuity of useful action

Data Source

PatentEP4035315B1Automation network and method for transmitting data in an automation network

Publication Date: 2022.12.21 BECKHOFF AUTOMATION GMBH

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AI summary

An automation network (100) has at least one master station (205), at least one switching device (210) and at least one slave station (215). The master station (205) has master ports, the switching device (210) has switching ports, and the slave station (215) has slave ports, which each comprise a transmitting unit TX and a receiving unit RX. The master station (205) is configured to output a first telegram (220) to a first switching port (500) via a first master port (400) and a first master communication path (310) and to output a second telegram (225) to a second switching port (515) via a second master port (415) and a second master communication path (315). The switching device (210) is configured to forward the first telegram (220) to a first slave port (600) of a slave station (215) via a first slave communication path (320) and to forward the second telegram (225) to a second slave port (620) of a slave station (215) via a second slave communication path (325). When in fault mode, the switching device (210) and the slave station (215) are configured to send the first telegram (220) back to the master station (205) so that it receives the first telegram (220) via the first master port (400) and/or to send the second telegram (225) back to the master station (205) so that it receives the second telegram (225) via the second master port (415).