MMS Server

The MMS Server equips the M1 controller with the capability of communicating in accordance with the standards IEC 61850 or IEC 61400-25. These standards describe manufacturer-independent communication between plants for energy generation and distribution. They enable the seamless integration of an ever-increasing number of heterogeneous plants, such as wind turbines or CHPs, in a control station or in a mixed network. 

The standards IEC 61850 and IEC 61400-25 extend far beyond pure data communication. They also define the data modeling and thus offer an object-oriented view of the system. Objects such as generator, power switch, transformer, voltage controller, or rotor are standardized. For each of these objects the designation, data points, and services for access to the data are specified. 

Communication between Server and Clients may be secured and encrypted by means of TLS certificates. This enables end-to-endprotection for critical infrastructure applications.

While TCP/IP-based MMS is mostly used as a SCADA interface, the multicast-based GOOSE is also available for automation with real-time requirements for fast transmission of spontaneous value alterations. 
Both processes are configured via the same standardized XML file, which can also be used for scheduling the entire network.

The MMS Server from Bachmann electronic maps the automation process variables to the attributes of the IEC 61850 or IEC 61400-25 address space. The user of the MMS Server determines the standardized ICD file (ICD = Intelligent Electronic Device Capability Description), what information of the plant is represented by the server, and are therefore visible to the client (e.g. the control station). This enables individual adaptation to different plants or modular expansion stages. 

The GOOSE Publisher feature enables, in addition or as an alternative, the selected process data to be distributed as prioritized multicast messages in the network. To do this, only the corresponding GOOSE control blocks need to be configured in the ICD file.

Capabilities according to IEC 61850/IEC 61400-25

• Support for Ed. 1 and Ed. 2 of IEC 61850
• The object definition decides between IEC 61850 or IEC 61400-25
• Transport layer MMS (Manufacturing Message Specification) according to ISO 9506
• GOOSE (Generic Object-Oriented Substation Event) Publisher in accordance with performance class 3
• Generating reports and GOOSE messages
• Browsing of objects with presentation of structures and elements in plain text 
  (self-describing system)
• Reading and writing of values (Get / Set data values)
• Managing data sets
• Direct operate, Select before operate (single and multi-level command control, each with »normal« or »enhanced« security)
• File transfer

Features

• It is started as a stand-alone software module
• No special hardware required; purely software solution for all M1 CPUs except for ME 203
• Simultaneous operation of client, server, GOOSE Publisher, and GOOSE Subscriber on one controller
• Configuration of the variable set via standardized ICD file (XML format)
• Mapping of process variables to IEC variables in a CSV file
• Cyclic scan of report and GOOSE data to automatically detect and send value alterations
• In addition, triggering is also available from the application software
• Automatic deadband calculation (db, zeroDb) for analog measured values (MV, CMV) for reducing network load
• Integrated into the mechanisms in the controller for rights validation and logging write accesses and connections
• Customer application has been certified successfully as per IEC 61850 Ed. 2 by TÜV SÜD
• Can be operated together with other protocols (OPC, QSOAP, Telnet etc.) on the same Ethernet interface of the M1 controller
• CPU load can be limited

IT Security for MMS

• Secure communication according to IEC 62351
• TLS Certificates are stored in file-based PKI (Public Key Infrastructure) on the controller
• Authentication of clients by certificate (TLS or MACE) or by connection parameters
• Key length of 1024 and 2048 Bit supported
• Encryption of communication with session key
  Exchange of session key (re-keying) is possible after connection, this must be supported by the client
• XML Configuration of expected clients with their individual connection parameters and certificates, enables easy roll-out in substations and wind parks
• Sample configuration and certificates for testing reasons are included. For productive systems, own certificates must be used