by Walter R. Phillips, GE Energy Management
As the smart grid grows bigger and smarter, electric utilities need flexible solutions to keep pace with its dynamic and increasingly sophisticated requirements. The efficient capture, communication and processing of meter data is critical to a smoothly functioning smart grid but involves several related issues: securing, controlling and managing the cost of transmitting the data and developing the capacity to transmit it throughout a utility network.
General Electric Co. (GE) has been collaborating since 2009 with Houston-based CenterPoint Energy to advance energy purchase, delivery and usage.
CenterPoint’s Advanced Metering System (AMS) project required it to meet an ambitious challenge in retrieving and collecting meter data: CenterPoint had to connect more than 5,500 Itron OpenWay meter data collection devices, or cell relays, with more than 2.2 million digital smart meters throughout its 5,000-square-mile Houston service territory to serve a dynamic, competitive marketplace.
CenterPoint needed an equipment and technology provider that could support cybersecurity, open networking standards and protocols and that could provide high reliability and system availability, bandwidth for network loading and future network capacity, robust network management tools and processes, and a record of meeting the needs of utility communications systems. The solution also had to be scalable to support CenterPoint’s multiyear build out and be rugged enough to cope with Houston’s heat, humidity and major weather activities.
CenterPoint chose GE’s Digital Energy business for its backhaul telecommunications system. GE provided MDS Mercury 3650 WiMax radios for the AMS communications network that links CenterPoint’s meter network to the meter collection devices , along with the engineering, program management and support services that map and execute the WiMax network.
The telecommunications process for the $530 million project begins with the AMS network’s gathering the meter data and passing it on to the more than 5,500 meter collection devices over a wireless mesh network. Each device then connects to a WiMax radio, which transmits the meter information to one of 140 MDS Mercury 3650 radio access points. Finally, the meter data is transferred to CenterPoint’s data center via microwave, fiber-optic cable or both for storage and processing.
“We opted for GE’s WiMax technology because it has the speed, durability, scalability and reliability we need in a private communications infrastructure that can support our vast smart grid coverage area,” said Kenny Mercado, CenterPoint’s senior vice president of advanced metering deployment.
Consumers can become more energy efficient. Customers have user-friendly access to their 15-minute interval consumption data, and the utility and consumers have benefited from more than 3 million service orders–move-ins, move-outs, re-reads, etc.–executed remotely, faster and cheaper. Retail electrical providers can expand service offerings, including pre-paid service and time-of-use rates, and establish platforms to offer future home appliance monitoring and control.
Multiple Solutions Focus
Other MDS technologies implement data communications in the smart grid. GE’s iNET-ll industrial wireless radio provides unlicensed, two-way, long-distance, point-to-multipoint communications that connect users with Ethernet and serial controllers. The design combines a high-speed digital transmission system with frequency-hopping spread spectrum (FHSS) technology to accommodate applications that require high data capabilities in a communications system. The radios have layers of cybersecurity, handle services in a single infrastructure and allow those services to operate simultaneously on the same network. A radio can roam among access point locations with unbroken data handling. It has high reception sensitivity for noisy environments and long-distance communications, and because it is industrially hardened, it is approved for use in hazardous locations and temperatures from 30 C to more than 60 C. The radios operate in the 900-megahertz (MHz) frequency band and are available in remote models that support serial-only, Ethernet-only or both interfaces. They can replace existing wired or wireless communication devices and transition from a serial-based supervisory control and data acquisition (SCADA) infrastructure to Internet Protocol/Ethernet without disrupting day-to-day operations.
GE’s 900-MHz 9710 digital radio transceiver is a data telemetry radio in the two-way, point-to-multipoint environment of SCADA and distribution automation. The radio’s microprocessor control and digital signal processing (DSP) technology are intended to make communications very reliable in adverse conditions such as interference or difficult signal paths. As DSP adapts to differences among components from unit to unit, it establishes a consistent, repeatable performance. The radio transceiver provides up to 19.2Kbps data throughput and has a range of up to 50 miles.
A 9710 radio system in a SCADA configuration can economically replace a network of remote monitors linked to a central location by an expensive leased telephone line.
The SD Series industrial wireless radio, GE’s latest generation of MDS-licensed narrowband wireless devices, contains features common to the iNET-ll, 9710 radios or both, including an interface with both serial and Ethernet devices and the ability to operate them on a single network, broad coverage flexibility up to 50 miles, reception sensitivity for long-distance communications, suitability for multiple industry protocols, capability to maintain performance and wide coverage support despite transmission obstructions, easy migration from serial to Internet Protocol/Ethernet communication, durability for hazardous locations and multilayered cybersecurity.
SD Series radios connect host systems to a single access point radio and multiple devices to a single remote radio. They send data at speeds up to 65Kbps for the SD2 and SD9 models and can detect and avoid collisions that would prevent complete transmissions without data loss.
The TransNET wireless receiver also has capabilities that overlap one or more of GE’s other wireless platform solutions for industrial communications within the smart grid. The TransNET wireless receiver uses FHSS for long-range data transportation–in this case at speeds up to 115.2Kbps. The DSP technology in the 9710 radio is here, too, and provides self-equalization, automatic CRC/ARQ and forward error correction. The receivers also have the same two-way, point-to-multipoint communications facility as their iNET-ll and 9710 counterpoints and can transmit data up to 30 miles. They work in the same temperature range as SD Series radios. TransNET communication systems also can be configured as repeaters to extend the network’s operating range and can be deployed as multiple repeaters at any level of the network to prevent a single radio failure from disabling the entire network.
A smarter smart grid demands devices that deliver secure, mobile and flexible data communications. This technology evolution is helping power providers worldwide find more efficient ways to communicate data and realize smart grid potential.
Walter Phillips is project director of meters and sensing systems at GE Energy Management. He and his execution team have been engaged and delivering the GE solution for more than three years in direct collaboration with CNP. Reach Phillips at firstname.lastname@example.org.