With the Sicam SGU, Siemens’ Smart Grid Division has launched a communications-capable field device on the market. The unit can be used to connect distributed energy resources to a grid control or energy management system by means of communications technology. Used as an input/output (I/O) unit, Sicam SGU allows power companies and public utilities to control and monitor decentralized power generation facilities and power consumers via the smart grid remote terminal unit. In particular, it can be used for bundling decentralized energy sources into a virtual power plant, for demand-response applications, and for setting up micro-grids.
Balancing out power generation and power consumption at all times is a bigger challenge for the control system in smart grids, with their many renewable energy sources and controllable loads, than in conventional grids. To meet this challenge, the system requires communications-capable I/O units such as the Sicam SGU to control and monitor the field level. To communicate with a control system such as Spectrum Power or the DEMS energy management system developed by Siemens, the field device uses an integrated mobile communications module or an Ethernet connection. Decentralized power generation facilities or power consumers can then be controlled via the device’s six I/O ports.
The integrated GPRS mobile communications card is also a cost-effective alternative to a fiber optic connection or to a separate external modem. Equipped with this card, Sicam SGU is able to connect distributed, renewable energy sources to control and energy management systems of all types. For example, the remote terminal unit can be used as a decentralized energy resources (DER) controller for virtual power plants in order to communicate with the energy management system. The Sicam SGU is also suited for integrating renewable energy sources in micro-grids. As a compact remote terminal unit, Sicam SGU enables the implementation of applications for energy flow control or data collection in local and distributed networks. In both cases, the IEC 60870-5-104 communications protocol is used for communication. When the Sicam SGU is utilized as a field device for demand-response management systems, it uses the interoperable, data-protected OpenADR (Automated Demand Response) communications protocol.
Siemens ensures that the required data privacy is maintained for all applications of its new remote terminal unit. A connection to a closed VPN (Virtual Private Network) based on IPsec (Internet Protocol Security) enables encrypted data transmission. When used without a mobile communications module, TLS (an integrated encryption protocol for secure data transmission via the Internet) establishes end-to-end data security for the OpenADR communications.