IEC 61850 Digital Substation Architecture

IEC 61850 defines standardized communications for substation automation systems, enabling interoperability between protection relays, IEDs, SCADA platforms, and monitoring systems. Digital substations typically consist of two primary networks:

• Process Bus – transports sampled values and protection messaging from merging units and field devices.
• Station Bus – connects protection relays, gateways, and SCADA systems within the control network.

HSR (High-availability Seamless Redundancy)

HSR networks create ring-based topologies where each node forwards traffic in both directions. Frames are duplicated and transmitted along both paths to ensure that communication continues even if a network link fails.

• Zero recovery time for network failures
• Ring topology connecting protection relays and IEDs
• Commonly used in bay-level protection networks
• No need for spanning tree protocols

PRP (Parallel Redundancy Protocol)

PRP networks use two independent Ethernet networks operating in parallel. Devices transmit duplicate frames across both networks, ensuring seamless communication if either network fails.

• Two fully independent LAN networks
• Zero switchover time
• Ideal for station bus and control networks
• Supports integration with non-PRP devices via RedBoxes

Substation Network Design Considerations

• Define clear separation between process bus and station bus networks.
• Deploy redundant core switching infrastructure for SCADA and station control systems.
• Use HSR rings for protection relay communication where deterministic recovery is required.
• Use PRP architectures for station-level networks requiring extremely high availability.
• Segment networks using VLANs and Layer 3 routing to improve security and performance.

Cybersecurity for Digital Substations

Substation communication networks should be designed to support modern cybersecurity frameworks including IEC 62351 and IEC 62443. Recommended practices include network segmentation, secure remote access, centralized monitoring, and encrypted management communications.

ORing Networking Platforms for Digital Substations

ORing industrial Ethernet switches provide the rugged design, high availability, and advanced redundancy features required for modern substation automation networks.

• Support for IEC 61850 digital substation architectures
• HSR / PRP redundancy support (IEC 62439-3)
• Rugged hardware compliant with IEC 61850-3 and IEEE 1613
• Advanced Layer 3 routing and network segmentation
• Centralized management using Open Vision Pro