Its about Advanced Metering Infrastructure Functionality, AMI Functions, Unified Modeling Language, AMI Communications Infrastructure, Instrumentation in AMI.
Advanced Metering Infrastructure Functionality – AMI Functions
What is meant by the term “functions”, with respect to an AMI Functions or any other system concept, in the Unified Modeling Language (UML). It is thought that any functions enacted in an AMI are likely to be performed for one of four main purposes, Instrumentation, IT Infrastructure, Data Acquisition and Control and User Interaction.
By defining what the system should do (desired functionality of Advanced Metering Infrastructure) we can ultimately specify how it should work.
1. Unified Modeling Language (UML) Context
The functions of a system are the interactions that can occur between the system and its actors (through an interface). Actors are external agents to a system that are capable of making autonomous decisions and providing asynchronous inputs to the system.
An interaction is a sequence of actor inputs (e.g., a user clicking a mouse button) and system outputs (e.g., displaying some data on the user’s screen). Typically, the actor is trying to achieve some objective (log in, search for data, update data, perform a calculation, etc.) when they interact with the system.
2. Instrumentation in AMI
The following is a list of functions that the AMI should exhibit from an Instrumentation perspective:
2.1. Smart Meters in the home will be made tamper proof to malicious damage or general meter fraud/electricity theft.
2.2. Local clock at all equipment will be synchronized to a single, reliable time source within the AMI.
This facilitates a practice of consistent time-stamping of information across the AMI.
2.3 Smart Meters will be read on a regular basis for billing purposes. An acceptable level of accuracy must be specified.
Refer to §6 for specific guidelines on accuracy.
2.4 Smart Meters will be able to transmit instantaneous voltage and current measurements, to the Utility.
2.5 Smart Meters will be able to transmit instantaneous power measurements (W and VAr), which are import and export specific (i.e., 4-Quadrant), to the Utility.
2.6 Smart Meters will be able to transmit energy balances (kWh and kVArh), which are import and export specific (i.e., 4-Quadrant), to the Utility.
2.7 Smart Meters will be able to transmit Power Quality measurements to the Utility, as required.
2.8 The AMI shall make provision for the logging of persistent Power Quality issues, such as outages.
2.9 The AMI (in Instrumentation Aspect) shall incorporate advanced price tariff structures, e.g., Time-Of-Use, the nature of which can be viewed remotely by end-users.
2.10 For premises within which embedded generation and load require quantification, import and export measurements (Energy, Power, etc.) for both activities shall be distinguishable within the AMI.
This point has relevance regarding the integration of DER (Rooftop PV, etc.). Net metering of such examples is undesirable as future energy policy may dictate that different price tariffs shall apply to embedded generation and load from the same building.
Alternatively, a net export tariff may be assigned to any net units of grid-exported generation. Future direction on this point (ECRA, et al) is unclear and so this point seeks to cater for either eventuality (i.e., feed-in-tariff or net-metering approach).
2.11 All equipment will be able to function in the presence of Electromagnetic Interference (EMI).
2.12 All equipment will be able to function in the presence of extreme environmental conditions.
2.13 The AMI shall possess functionality to help it validate data received, identify potential errors or inconsistencies, and auto-recover from minor disturbances.
2.14 Equipment will be robust to mis-configuration or firmware corruption.
3. AMI Communications Infrastructure
The following is a list of functions that the AMI should exhibit from a communications and interface perspective:
3.1 The AMI shall feature bi-directional communications, allowing both data collection and control functions to be implemented across any channel connecting two, or more, devices.
3.2 All equipment will be able to automatically register to the AMI.
3.3 The firmware of Smart Meters can be updated remotely by the Utility.
3.4 The communications network shall be able to automatically reconfigure to adapt to changes in either the power network infrastructure or the communications network itself.
For instance, in cases for which Power Line Carrier (PLC) communications are used, if the local grid topology changes due to Normally Open Points (NOPs) closing to form a new configuration, or other similar Utility imposed instructions, the end-point devices in the AMI (Smart Meters, etc.) should still be able to communicate to the Utility.
3.5 AMI shall be able to eliminate cyber security threats 3.
3.6 Metered data taken from customer devices shall be reported to the Utility in such a way that the data privacy of customers is preserved.
3.7 AMI shall have data retention capability to preserve metered data in the event of communications or power supply interruptions.
3.8 No metered data shall be lost during brief power interruptions.
3.9 The AMI shall be compatible with existing legacy systems. For example, pre-existing billing and/or enterprise software.
3.10 The AMI shall be based on standard interfaces and data exchange formats to enable integration between different vendor solutions.
The installation of one group of meters (plus accompanying software) by a particular vendor should not preclude the use of another vendor to install meters and software. The top-level architecture of the AMI shall be able to handle the integration of multiple Head-End software systems.
3.11 The AMI may be composed of separate individual sub-systems, designed by different manufacturers. These systems should be inter-operable, using open standards and interfaces wherever possible.
3.12 Equipment shall support more than one port and/or communications media interface (e.g., Serial link, Ethernet, F.O., Infrared, etc.) option.
3.13 A potentially wide range of controllable, “smart” devices may be deployed within the home. The integration of these devices shall be simple and not require external supervision in the home by trained personnel (from the Utility).
Smart devices will be “plug-and-play” by nature. Simple integration means that a home user should be able to buy a smart device and, with minimal effort, be able to use the device and utilize its “smart” functionality via connectivity to the AMI.
3.14 Smart Meters will be able to access information from “smart” devices in the HAN via a Communications Gateway device.
4. Data Acquisition and Control
The following is a list of functions that the AMI should exhibit from a data acquisition and control capability perspective:
4.1 Price tariffs can be programmed remotely by the Utility.
4.2 The Utility shall be able to monitor all AMI performance, connectivity and diagnostic data concurrently, via a NOC or other means. This will give an overview of the communications health of the system.
4.3 The AMI shall report interruption information (outages, etc.) to the Utility.
4.4 Smart Meters can be remotely disconnected or re-connected by the Utility via the AMI.
This functionality shall be extended to energized PV inverters, i.e., these devices cannot remain energized whilst the electricity supply to home, or wider neighborhood, has been disconnected.
4.5 The Utility will be able to directly control the power within an agreed selection of houses and/or commercial buildings.
Loads can be managed interactively via demand set-point control commands issued by the Utility. This may be useful in situations where the Utility needs to urgently correct for an imbalance of load and generation, denoted by a drop in system frequency.
Controllable homes/business premises must be willing participants in any control scheme. This might be enacted as part of different tariff regimes. Thus, a derived function from this will be to activate or deactivate power control within a particular property.
For such premises the Utility shall be able to control devices within the home/business, i.e., behind the Smart Meter.
4.6 Smart Meters can be read on an ad-hoc basis.
The reading of Smart Meters does not have to be scheduled in advance (but can be). An “on-demand” read of Smart Meters can be performed, as required, in addition to the billing cycle.
4.7 The Utility shall be able to obtain load profile information for any metered area in the AMI.
4.8 The Utility shall be able to monitor devices within the home, behind the main Smart Meter.
The control of such devices is catered for separately within Function §3.4.5
4.9 The AMI shall be able to filter data received and identify trends for back-office analysis 3.4.10 Smart Meters shall be able to send Alarms and Events to the Utility
4.11 Historical metered data can be retained for instant recall and use at a later date for on-line analysis and trend identification.
4.12 The data historian shall be able to retain compressed data for at least 5 years.
5. User Interaction
The following is a list of functions that the AMI should exhibit from a user-interaction perspective.
5.1 Customers will be able to observe their current price tariff and any alerts or recommendations broadcast to them by the Utility.
For instance, customers should be warned if they are close to breaching their current tariff threshold.
5.2 Customers will be able to arrange for the pre-payment of their energy supply under particular tariff regimes.
5.3 Device operation schedules can be programmed by the residential user via an In-Home Display (IHD).
5.4 Smart Meters shall provide warnings to customers/suppliers if Voltage Quality (e.g., high harmonic content or persistent sags/swells) falls to such a level that electrical appliances could be damaged.
5.5 The system shall provide different levels of user access and support entity access, with complete logs of each session being retained.
All article related to Smart Metering Technology are linked below step by step.
Advanced Metering Infrastructure | Smart Metering Technology
Advanced Metering Infrastructure Functionality – AMI Functions
Advanced Metering Infrastructure System Design Architecture
Advanced Metering Infrastructure Components
Advanced Metering Infrastructure Functional Requirements
Domestic Smart Meter Installation – ANSI 12.20 Electricity Meters
Data Concentrator Unit | DCU Principle with Technical Specification
Head End System for Advance Metering Infrastructure
Meter Data Management System – IEC 61968-9
Wireless Communications Principles and Industrial Practice