Smart Grid and Advanced Metering Infrastructure (AMI)
One of the key tenets of Grid Modernization is the implementation of Smart Grid and Smart Grid technologies. Smart Grid can be thought of as instrumenting the traditional electric grid with much more sensor and control technology to allow for two-way communication between the utility and its customers. Integration of information, telecommunications and new power engineering technology provides for a much more dynamic two-way communicating grid, where generation and consumption can be much more tightly aligned. This allows for faster outage identification and resolution (response and recovery) by rerouting electricity to isolate the smallest possible portion of the grid which is out. With more sensor infrastructure the grid can be more closely monitored to improve predicative failure analysis and reliability.
One core component of the smart grid is the implementation of an AMI system. AMI systems have three primary components:
- Software headend
- Network Communication System
The headend is specific to the solution installed. It typically has deep integration with the connected metering infrastructure or any endpoints within the solution. The Network Communication System is likely one or combinations of several different technologies, including cellular, mesh (many-to-many communication) and star (many-to-one communication) radio configurations and Power Line Carrier (PLC) solutions. Different meter types can be integrated within a given solution. Meters tend to be standards-based and fall into two broad categories (1) ANSI-based C12.22/C12.19, where C12.22 is the networking protocol and C12.19 is the table structure for data that is passed between the meter and headend and it’s partner (2) IEC-based DLMS/COSEM.
Typically all AMI systems have a common functionality set which encompasses:
- Solution Provisioning (including Security)
- Data collection – Push/Pull (Readings/Events)
- Alarming – Push
- Configuration Management
- Firmware Management
Push indicates data is generated at the meter and sent to the headend without a request, while for pull the headend will request data be sent from the end device.
AMI system technology continues to evolve. New systems are being introduced where small applications (apps) can be executed on field devices at the edge of the network, performing analytics on much higher frequency data. This eliminates the issue of trying to bring back large amounts of data from each device to perform analytics in the back-office. New, faster Field Area Networks (FAN) are being implemented, yielding as much as 1.2Mbps of throughput.
In general, AMI systems have proprietary head-ends, meaning that the integration of head-end to the back office is different for each solution. Although utilities often procure from a single vender, consolidation within the industry is leading to single utilities needing to support multiple AMI solutions including multiple head-ends, with different interfaces into the utility back office. This is likely to continue to proliferate as more advanced DA devices running on FAN are introduced in Grid Modernization. Common protocols and processes are becoming necessary in order to alleviate this overabundance. Another potential solution is to include a new Advanced Control Center as proposed by Wise Men Consultants. Here, an integration of system-of-systems allows for simpler and more cohesive management of the overall solution.
Further discussions concerning more advanced FAN technologies and Edge computing will be included in later blogs.