Communication Networks and Systems In Substations IEC 61850 Primer - Communication Networks and Systems In Substations February 16, 2005

61850 Scope

Abstract Communications Service Interface ACSI Defines a set of Objects Defines a set of Services to manipulate and access those objects Defines a base set of data types for describing objects

Functional Constraint Anatomy of an IEC61850 Object Name MMXU1 MX V MMXU2 MX A Logical Device (e.g. Relay1) Physical Device (network address) Functional Constraint Logical Nodes “MMXU2$MX$A” = Feeder #2 Current Measurements

Logical node groups M Metering and measurement (8) S Sensor and monitoring (4) X Switchgear (2) T Instrument transformers (2) Y Power transformers (4) Z Further power system equipment (15) L System LN (2) P Protection (28) R Protection related (10) C Control (5) G Generic (3) I Interfacing and archiving (4) A Automatic control (4) Examples: PDIF: Differential protection RBRF: Breaker failure XCBR: Circuit breaker CSWI: Switch controller MMXU: Measurement unit YPTR: Power transformer

Services Examples GetData – Read SetDataValues – Write GetDataDirectory – Read list of object names

ACSI Services Enable Self Describing Devices

IEC61850 Profiles

IEC61850 Documents Mapping to MMS and Ethernet Basic principles Part 1 Glossary Part 2 General Requirements Part 3 System and project management Part 4 Communication requirements Part 5 Substation Automation System Configuration Part 6 Basic Communication Structure Part 7 Mapping to MMS and Ethernet Sampled Measured Values Part 8 Part 9 Mapping to Ethernet Conformance testing Part 10

IEC61850 – Primary Parts Part 6-1: Substation Configuration Language (SCL) Part 7-2: Abstract Communications Service Interface (ACSI) and base types Part 7-3: Common Data Classes (CDC) Part 7-4: Logical Nodes Part 8-1: Specific Communications Service Mappings (SCSM) - MMS & Ethernet Part 9-2: SCSM - Sampled Values over Ethernet Part 10-1: Conformance Testing

IEC61850 Substation Architecture MU = Merging Unit MU PT1 Optical CT PT2 CT2 PT Relay MU Publishes V/I/Status Datasets Relay(s) Subscribe to I/O Station Bus - 10/100/1000 MB Ethernet Process Bus .1/1/10GB Ethernet Clk1 Clk2 Remote Access Network IED

Sampled Measured Values

Peer to Peer Communications Functional Requirements Relay Relay Relay Relay . . . Bkr 1 Bkr 2 Bkr 3 Bkr N Trip BFI Message delivery to multiple devices simultaneously Fast Delivery (< 4ms)

IEC61850 Generic Object Oriented Substation Event - GOOSE Device to multi-device communication – Local or Wide Area Bridgeable but Non-routable User-defined Dataset sent in an Ethernet Multicast message Message sent on change of state as well periodically to enable detection of device failure Reliability effected through message repeat GOOSE Header: Multicast Address Name Time Until Next GOOSE Etc. User-Defined Dataset Status Information Analog Values Data Quality Time

SCL – Substation Configuration Language Description language for communication in electrical substations related to the IEDs XML based language that allows a formal description of Substation automation system and the switchyard and the relation between them IED configuration

SCL File Types SSD: System Specification Description. XML description of the entire system. SCD: Substation Configuration Description. XML description of a single substation. ICD: IED Capability Description. XML description of items supported by an IED. CID: Configured IED Description. XML configuration for a specific IED.

Benefits of IEC61850 High-level services enable self-describing devices & automatic object discovery saving $$$$$ in configuration, setup and maintenance. Standardized naming conventions with power system context eliminates device dependencies and tag mapping saving $$$$ in config., setup, and maint. Standardized configuration file formats enables exchange of device configuration saving $$$$ in design, specification, config., setup, and maint.

Benefits of IEC61850 - 2 Higher performance multi-cast messaging for inter-relay communications enables functions not possible with hard wires and save $$$$ in wiring and maintenance. Multi-cast messaging enables sharing of transducer (CT/PT) signals saving $$$$ by reducing wiring and connection costs