Semitech power line communications used in Chinese smart grid meter deployments

SINGAPORE: Semitech Semiconductor, a provider of power line communications solutions that enable the transformation of the electricity grid into a smart grid, announced that its GS18 power line communications (PLC) semiconductor is now deployed in volume in LangFang Gao Shan smart meters installed on the China State Grid in Hebei Province.

In its initial deployment phase, Gao Shan has installed over 5,000 Semitech-based PLC smart meters in two residential sites for building sub metering and one village site for remote-reading of meters, demonstrating PLC performance and reliability unmatched in China. The meters have a power line node to node distance of up to 3 KM and implement real-time reading of meters reaching as high as 18 floors in buildings.

Data communications is at a sustained throughput data rate of 18 Kbps. Semitech's GS18 uses 18 independent OFDM channels for data transfer. To ensure the highest reliability, Gao Shan uses the GS18's redundancy capability to implement 18 times redundancy, using all 18 channels to send and receive the same data. This results in sustained throughput at 1 Kbps with no errors. The raw data rate of the GS18 is 125 Kbps. This is an AMI (advanced metering infrastructure) system with bidirectional communications with each meter and the controller every 30 minutes. There are 500 meters per network controller.

The GS18's reliability and data throughput enables connection of more meters per node than existing solutions, which reduces the installation cost of large numbers of meter deployments by decreasing the number of concentrators and network controllers. With the reliability and performance of this smart meter installation, the Northern China (Huabei) Power Supply Bureau can implement AMI to provide energy management capabilities throughout the Huabei Province.

To achieve reliability and performance, Semitech's GS18 uses modulation and signal processing technology that is adjustable in speed but also 'frequency agile' to deliver highly robust and reliable communications. The GS18 adapts to noisy environments, choosing the most effective transmission frequency. It also employs a Multi Access scheme to provide additional robustness and enables communication with multiple nodes simultaneously -- thus providing the customer better results via the highest throughput, most reliable communication available. Energy management using the smart grid is critical to the City of LangFang and the China State Grid. These initial installations enable the Government of LangFang to implement reliable and effective power management in the city.

Headquartered in LangFang of Hebei province, China, LangFang Gao Shan is a leader in smart grid infrastructure solutions. LangFang Gao Shan has used the Semitech power line communications in its medium voltage (MV) products to provide the highest power line communications reliability, range and throughput on to the China State Grid since 2007. Gao Shan has recently brought this same reliability and performance to the volume low voltage smart metering market with introduction of its PLC Smart Meters using the GS18 PLC modem.

"Until now, smart meters in China have been used for lower performance meter reading applications. To enable the benefits of the smart grid, higher reliability, data through put and range are required," noted Chen Yong Shan, chairman of LangFang Gao Shan. "This is what the Gao Shan meters using the Semitech GS18 PLC achieve." Gao Shan, Semitech and Harbin University architected the GS18 to implement the most reliable power line communications.

Unique capabilities of Semitech's GS18 include:
* Programmable modulation to improve communications reliability: OFDMA transceiver with 54 carriers and up to 18 channels.
* High data transfer rates in noisy environments: User selectable between BPSK modulation for higher carrier voltages and higher noise immunity and QPSK modulation for higher data rate dynamically.
* Narrow band emulation and low frequency mode putting channels in CENELEC frequency range.
* Selectable frequency range for each carrier dynamically.
* Transmit power regulation.
* Error correction.