Chapter14
Smart grid architecture model (SGAM)
Definition
The important reference regarding smart grid systems and architecture of the smart grid as whole provides the Smart Grid Architecture Model (SGAM).
Note
The original scope of the SGAM was created in the M/490 mandate of the European Commission (EC) to the European standardization bodies CEN (ComitéEuropéen de Normalisation), CENELEC (European Committee for Electrotechnical Standardization), and ETSI (European Telecommunications Standards Institute).
Definition
The SGAM acts as a reference designation system providing three main axis for the dimensions: Domains, Zones, and Interoperability Layers as depicted on Fig. 14.
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14. Smart Grid Architecture Model framework [8]
Fig. 14. Smart Grid Architecture Model framework [8]
As the key enabler of smart grid is seen the interoperability. The systems are considered as interoperable, if they are able to perform cooperatively a specific function by using information which is exchanged.
Definition
There are 5 layers of interoperability defined in SGAM:
  • Business Layer - Represents the business view on the information exchange related to smart grids. Can be used to map regulatory and economic (market) structures and policies, business models, processes, products and services.
  • Function Layer - Describes functions and services including their relationships from an architectural viewpoint. The functions are represented independent from actors and physical implementations in applications, systems and components.
  • Information Layer - Describes the information that is being used and exchanged between functions, services and components. It contains information objects and the underlying data models.
  • Communication Layer - Describes protocols and mechanisms for exchanging information between components
  • Component Layer – Describes physical distribution of all participating components in the smart grid context.
Definition
Domains basically represent the energy conversion chain similarly to the basic scheme of the electric grid as provided on Fig. 1, they can be described as follows:
  • Mass production - Represents generation of electrical energy in bulk quantities, such as by fossil, nuclear and hydro power plants, off-shore wind farms, large scale solar power plants, typically connected to the transmission system.
  • Transmission - Represents the infrastructure and organization which transports electricity over long distances.
  • Distribution - Represents the infrastructure and organization which distributes electricity to customers.
  • DER - Represents distributed electrical resources directly connected to the public distribution grid, applying small-scale power generation technologies (typically in the range of 3 kW to 10.000 kW). These distributed electrical resources may be directly controlled by DSO.
  • Customer premises – Represents both - end users of electricity, also producers of electricity. The premises include industrial, commercial and home facilities (e.g. chemical plants, airports, harbors, shopping centers, homes). Also represents the generation in form of e.g. photovoltaic generation, electric vehicles storage, batteries, micro turbines...
Definition
The Zones are orthogonal to the domains and basically represent the Information and Communication Technology (ICT) based power system management, controlling the energy conversion chain. There are two main concepts of aggregation:
  • Data aggregation – Data from the field zone is usually aggregated or concentrated in the station zone to reduce the amount of data to be communicated and processed in the operation zone.
  • Spatial aggregation – Aggregation from distinct locations to wider area (e.g. power system equipment is usually arranged in bays, several bays form a substation; multiple DER form a plant station, DER meters in customer premises are aggregated by concentrators for a neighborhood).
Definition
Based on this aggregation concepts an additional functional separation concept, the individual zones are described as follows [8]:
  • Process - Includes the physical, chemical or spatial transformations of energy (electricity, solar, heat, water, wind ...) and the physical equipment directly involved. (e.g. generators, transformers, circuit breakers, cables).
  • Field - Including equipment to protect, control and monitor the process of the power system, e.g. protection relays, bay controller, any kind of intelligent electronic devices which acquire and use process data from the power system.
  • Station - Represents the areal aggregation level for field level, e.g. for data concentration, functional aggregation, substation automation, local SCADA systems, equipment supervision...
  • Operation – Includes the operation of the energy system control in the relevant area, e.g. distribution management systems (DMS), energy management systems (EMS) in generation and transmission systems, microgrid management systems, virtual power plant management systems (aggregating several DER), electric vehicle (EV) fleet charging management systems.
  • Enterprise - Includes commercial and organizational processes, services and infrastructures for enterprises (utilities, service providers, energy traders ...), e.g. asset management, logistics, work force management, customer relation management, billing.
  • Market - Reflecting the market operations possible along the energy conversion chain, e.g. energy trading, mass market, retail market..
Interesting
It is possible to map all systems that are used in the smart grid to SGAM (e.g. the essential systems provided in Tab. 2).