Distribution Automation (DA) will further drive optimal regulation of the grid, maintaining security, reliability of supply and efficiency right down to the end consumers’ premises. The specific design priority of a particular ‘smart grid sensor’ will be determined by its usage mode, be it Protective Relaying, Quality Monitoring, Metering, or some combination of all three. Analog Devices provides a family of multi-channel, 3-phase analog-to-digital converter frontends (AFEs) optimally designed for power grid, monitoring, protection and metering. The high speed AD7606 enables both precision monitoring and protective relaying for up to 8 simultaneously sampled channels of I & V. The 6-channel, ADE7878, incorporates all the signal processing required to measure and calculates total active, reactive and apparent energy.
Control / Processing
As well as providing optimized ADCs that interface to the various physical sensors including current transformers, voltage transformers, shunt based schemes, active/passive optical architectures and Rogowski coils, Analog Devices also provides the necessary digital processing engines, covering the gamut from ARM® based processors through its family of Blackfin® processors(ADSP-BF53x/54x) to its most high performance SHARC® DSPs (ADSP-21469).
Aside from the local requirement to speedily actuate the protective relay, all the other data on the condition of the grid must be communicated back to the SCADA system. This will be through a combination of means that will include both wireless and wired communications. In the distribution part of the grid, with many dispersed 10KV level transformer stations, using Analog Devices' Short Range RF transceivers whose high sensitivity and immunity to interferers enable convenient and reliable communication of measured data to the grid’s communication backbone.
Isolation, whether it be for current/voltage sensing of the mains, or interconnection to the signal processing and communications infrastructure, Analog Devices iCoupler® technology is available as both standalone isolator products (ADuM148x) and embedded into a large range of functions including A/D Converters (AD7400A), CAN bus Transceivers (ADM3052/ADM3053) and RS-485/RS-422 Interfaces (ADM248xE/ADM258xE/ADM268xE). Precision, low noise, low power op amps like ADI's Opx177 family completed the signal conditioning demanded by the different current sensor signals while a broad portfolio of power management products ensures IC level power is reliably available for the entire signal processing chain.