VLAN-ID Assignment for Substation Automation Networks

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In process control and substation automation systems, the existing Ethernet switch-based communication networks face challenges in efficiently managing multicast messages and VLAN configurations due to the large number of message sources and receivers, leading to increased network load and complexity, especially in large systems with critical real-time communication needs.

Innovation Solution

A method to determine and assign VLAN-IDs in an Ethernet switch-based communication network by retrieving receiver IEDs from a formal system description, identifying message subsets, and attributing the same VLAN-ID to messages with identical receiver IEDs, while assigning different VLAN-IDs to messages with differing receiver sets, optimizing data flow and reducing the number of VLAN-IDs needed for selective forwarding.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If each message source is assigned a unique VLAN-ID, then message filtering precision is improved, but the number of VLAN-IDs increases leading to increased device complexity

Engineering Contradiction:
Improvemessage filtering precisionVSAvoidnumber of VLAN-IDs
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

Multiple message sources that share common receiver IEDs are merged into a single VLAN-ID. The patent applies a merging algorithm that groups senders based on their receiver sets, assigning the same VLAN-ID to all senders within a group. This reduces the total number of VLAN-IDs while maintaining precise message filtering, as receivers still receive only messages from their designated sender groups.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent segments the message sources into distinct groups based on their receiver assignments. By analyzing the formal system description, the system divides senders into segments where each segment shares identical receiver IEDs. This segmentation enables efficient VLAN assignment while preserving the ability to filter messages at the receiver level.

Inventive Principle:
Principle #1Segmentation

2Device complexity

If the number of VLAN-IDs is reduced, then device complexity is decreased, but message filtering capability may be compromised

Engineering Contradiction:
Improvenumber of VLAN-IDsVSAvoidmessage filtering capability
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The patent introduces a configuration tool as an intermediary that analyzes the formal system description and automatically generates optimized VLAN assignments. This intermediary process ensures that VLAN-ID assignment maintains precise message filtering capabilities by carefully grouping senders based on their receiver sets, preventing any loss of filtering accuracy while reducing the total number of VLAN-IDs.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The system uses feedback from the formal system description to verify and adjust VLAN assignments. By continuously checking the message flow definitions and receiver assignments, the system ensures that each VLAN-ID assignment maintains the necessary filtering precision, allowing for reduced VLAN-ID count without compromising message delivery accuracy.

Inventive Principle:
Principle #23Feedback

3Adaptability or versatility

If manual VLAN configuration is performed, then configuration flexibility is improved, but engineering time and errors increase

Engineering Contradiction:
Improveconfiguration flexibilityVSAvoidengineering time
Core Design Contradiction:
Adaptability or versatilityVSLoss of time

Solution Approach 1:

The patent performs preliminary analysis of the formal system description to automatically determine optimal VLAN assignments before system deployment. The configuration tool pre-processes the message flow definitions and receiver assignments to generate VLAN configurations in advance, eliminating the need for manual configuration during engineering and reducing the likelihood of configuration errors.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system employs self-service configuration where the formal system description automatically provides the information needed for VLAN assignment. The configuration tool extracts receiver set information directly from the SCD file and autonomously generates VLAN-ID assignments without requiring manual intervention, thereby reducing engineering time while maintaining configuration accuracy.

Inventive Principle:
Principle #25Self-service

Data Source

PatentEP2564563B1Determining VLAN-ids for a switched-based communication network of a process control system
Publication Date: 2018.11.21 ABB (SCHWEIZ) AG
  • EP2564563B1 patent drawingFigure 1a~1b
  • EP2564563B1 patent drawingFigure 2~3

AI summary

The present invention is concerned with a Process Control (PC) or Substation Automation (SA) system with appropriate message filtering based on Virtual Local Area Network identifiers VLAN-IDs as communication sub-network identifiers. The VLAN-IDs are determined in order to optimize data flow in the sense that receiver IEDs only receive the intended messages, while at the same time the number of sub-network identifiers is reduced to a maximum extent. Restricting the real time traffic in such a way will ensure proper operation of the systems, and particular of large SA systems using GOOSE for interlocking and having sensors connected with the Sampled Value (SV) protocol according to IEC 61850-9-2.