Smart E-Meter: AMR/AMI

Block Diagram

Design Considerations

Smart Electronic Meter (also known as Smart E-Meter) requirements around the world are rapidly evolving in response to market forces and governmental regulations mandating Smart Grid deployments in most areas of the globe.  Smart Grid applications such as dynamic pricing, demand response, remote connect and disconnect, outage management, network security, and reduction of non-technical losses are driving the need for increasing technological sophistication in today’s smart e-meter solutions.

Advanced Metering Infrastructure (AMI) projects are being deployed by utilities around the world and are rapidly proliferating after the early adopter projects in Western Europe and the United States. Today we see AMI projects being planned and in deployment in all regions of the world including countries such as China, Japan, Brazil, and South Africa.

At the heart of any smart meter is the basic energy measurement function. It is critical that utilities and consumers can rely on the accuracy, security, and reliability of this metering capability. Texas Instruments’ energy measurement products are designed to meet all of the requirements ANSI C12.20 and IEC 62053 accuracy for Class 0.2 and Class 0.5 meters – across the entire temperature range and a full 2000:1 dynamic input range. TI’s solutions are programmable and offer meter OEMs the ability to customize their products simply and easily using TI’s Energy Library software.

The requirements for a separate metering host, or applications processor vary by market and product. This is where the evolving Smart Grid requirements across the world significantly impact meter architectures. In some products an inexpensive 16-bit MCU with 128KB of flash is suitable as a host while other products can require a 32-bit MCU with 1MB of flash to support more advanced metering functions or multiple communications stacks. The most advanced of today’s e-meters may use an embedded microprocessor that operates a high-level operating system such as Linux with multiple megabytes of memory on the board. TI’s wide portfolio of MCU’s and microprocessors includes individual components suitable for any particular smart e-meter requirement.

AMI networks require robust communications between the individual meters and the data concentrators which aggregate meter data in a neighborhood area before sending that information to the utility’s central office through a backhaul link. AMI networks are either RF (mesh or star topology) or Powerline Communications (PLC). The choice between RF or PLC networks is usually driven by grid topology and geographical environment as these factors have enormous influence on network performance and infrastructure cost.  TI’s solutions for AMI networks span both RF and PLC and support most industry standards including IEEE-802.15.4g, PRIME, G3, IEEE-P1901.2, and ITU-G.990x.

TI’s RF transceivers for AMI networks offer industry-best performance for blocking and adjacent channel rejection which means that e-meter solutions have a larger link budget and can communicate over longer distances and in noisier RF environments. This improves network performance and lowers infrastructure costs for utilities.

PLC modems from TI are built upon the programmable TMS320C2000 MCU platform and provide the most flexible offering available. A single hardware platform can support multiple PLC standards including PRIME, G3, and IEEE-P1901.2. This makes it easier for smart e-meter OEMs to develop products for multiple markets quickly.  Smart electronic meter solutions are the bridge from the utility’s AMI network to the consumer’s Home Area Network (HAN). Just as with the AMI network, the HAN can use different physical layers across different global regions. RF networks for HAN often utilize low-power mesh networks with ZigBee. WiFi is becoming another option for HAN in some cases. A key consideration for HAN networks is the availability of a standardized application profile which allows all devices linked to the network to communicate. Smart Energy Profile is perhaps the most common HAN application profile. Smart Energy Profile 1.x runs on top of a ZigBee PRO stack but the upcoming Smart Energy Profile 2.0 standard will support multiple networking protocols and physical layers that use IPv6. TI’s hardware and software solutions for HAN cover all of the physical networks being deployed today.