PRIME Alliance goes Hybrid
The PRIME Alliance is a membership-based organisation that includes utilities, research institutes, chipset and software companies, smart meter and data concentrator suppliers, integrators and consultants. It is committed to addressing smart grid communication challenges for the low-voltage (LV) grid with an ecosystem of interoperable devices based on open and proven technologies.
The power line communications (PLC) channel poses a communications challenge as it is designed to carry power and not data. But the evolution of technology in recent decades has also made it possible to use it as an effective channel for communications in the low-voltage network.
Radio frequency (RF) technologies have also been used in other areas, providing good solutions to the same challenge. Both technologies have their strengths and weaknesses, so the PRIME Alliance has merged them to offer a hybrid solution, building a stronger and more versatile communications network.
The hybrid solution selected by the PRIME Alliance has been realized by integrating both physical (PHY) layers into a common PHY layer that is used by the same media access control (MAC) layer of the previous versions. A hybrid node can use both physical layers and maintain connectivity with neighbouring nodes with different technologies. For each connection the technology chooses the most suitable medium and modulation to provide stable and fast communication.
PLC-only protocols remain unchanged, making the integration fully backward compatible. The new solution allows hybrid and PLC-only devices to be integrated on the same network and is also fully compatible with RF-only devices, enabling new applications.
ADVANTAGES OF HYBRID
One of the main advantages of a hybrid solution is the extension of coverage, but it is not the only one. Power line communication (PLC) has many properties that make it a successful technology. The signal flows through the low-voltage network over long distances, reaching subway locations, easily passing through metal structures such as cabinets or reinforced concrete. For utilities, PLC networks use a proprietary medium that does not have to be shared by other applications and does not generate additional operating costs.
The main challenge is noise, but the advanced modulation techniques used in PRIME, which have enabled the evolution of electronics, allow good communication properties in most cases.
RF communication also has many properties that make it a suitable and complementary solution to situations where the PLC may have problems. Although both technologies have proven to be effective, it is not possible to guarantee full coverage with either technology. By combining both technological approaches, virtually full coverage can be achieved even in the face of changing media conditions.
As long as any link in a topology has coverage, whether through PLC or RF, the communication network will extend its coverage.
The combination of the two outperforms the separate technologies because the hybrid solution will choose the most appropriate technology for each link. But it also allows its use in new applications.
By using the PLC channel, the devices can provide valuable information for in-phase and line power network topology discovery. Using the RF interface, the devices can be used in low power scenarios or even working with batteries for gas and water metering. For example, hybrid technology can help solve local low-voltage power outages.
The PRIME Alliance offers an open, interoperable hybrid solution that caters to the new utility needs.
For more info, visit: https://www.prime-alliance.org/ solutions/prime-hybrid/.
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