IntelliGrid Architecture

System and Network Management Services

As can be seen in Figure 11 and Figure 12, two infrastructures must now be managed: the Power System Infrastructure and the Information Infrastructure. The management of the power system infrastructure is increasingly reliant on the information infrastructure as automation continues to replace manual operations, and is therefore affected by any problems that the information infrastructure might suffer.

Typical Simplistic Network Management by SCADA Systems–Electric power systems have been monitored and controlled by SCADA systems for many years. On the other hand, the information systems in the electric power industry have not been treated as a coherent infrastructure, but instead have been viewed as a collection of individual communication channels, separate databases, multiple systems, and different protocols.

Typically SCADA systems, in varying degrees, monitor whether communications are available with their (Remote Terminal Units (RTUs) and flag data as ‘unavailable’ if communications are lost. However, it is then up to maintenance personnel to track down the problem, which is a lengthy and ad hoc process. Every utility is different in the information available to its maintenance staff. Telecommunication technicians are generally responsible for tracking down any microwave or fiber cable problems; telecommunication service providers must track their networks; database administrators must determine if data is being retrieved correctly from substation automation systems or from GIS databases; protocol engineers must correct protocol errors; application engineers must determine if applications have crashed, have not converged, or are in an endless loop; and operators must filter through large amounts of data to determine if a possible ‘power system problem’ is really an ‘information system problem’.

System and Network Management Vision–Network and systems management are those functions required to manage the communication networks and the connected communications equipment. Systems management includes managing remote equipment. These are functions a system administrator uses in managing the distributed computing infrastructure and connected equipment. The development of these functions is taking place both within and outside of the energy community.

In the future, the problem of network and systems management will become increasingly complex as a variety of systems are anticipated as well as greater demands on the capabilities of these systems to assist system administrators. Traditional SCADA systems will no longer have exclusive control over the communications to the field, which may be provided by telecommunication providers, or by the corporate networks, or by other utilities. Intelligent Electronic Devices (IEDs) will have applications executing within them whose proper functioning is critical to power system reliability. Field devices will be communicating with other field devices, using channels not monitored by any SCADA system. Information networks in substations will rely on local ‘self-healing’ procedures that will also not be explicitly monitored or controlled by today’s SCADA systems.

The technology industry has developed two network management technologies: Simple Network Management Protocol (SNMP) for the Internet-based functions, and Common Management Information Protocol (CMIP) as an ISO standard. In each of these technologies, Management Information Base (MIB) objects must be specified representing the state of different equipment, applications, and systems. Although many MIB objects are generic enough to be used by electric power systems, some specialized MIB objects will need to be developed to represent some of the very specialized equipment used in power system operations.

Object Models for Network and System Management–Systems and network management functions are also supported by the application of object based communications. The IEC is currently working to develop network management objects for power system operations. In addition, the networking and telecommunications industries are working toward more sophisticated system administration infrastructures. Examples of possible types of network and systems management functions and objects for energy industry related IEDs are shown in Table 4 below.