Smart Grid Communication Protocols

Present power grids are getting replaced by smart grids, mainly for improving performance of existing power grid. Integration of electrical, electronics and computer science have led this technology more popular. Smart grid technology is characterized by full duplex communication, automatic metering infrastructure, renewable energy integration, distribution automation and complete monitoring and control of entire power grid. Wireless sensor networks (WSNs) are small micro electrical mechanical systems that are deployed to collect and communicate the data from surroundings. Security of wireless sensor based communication network is a major concern for researchers and developers. The address oriented design and development approach for usual communication network requires a paradigm shift to design data oriented WSN architecture. This paper is presents different communication protocols used in smart grid technology.


Fig. 1 Smart Grid
The unidirectional nature of communication and centralized generation makes the traditional grids less efficient, thus reengineering of current grid is required in such a way that they are able to meet increasing demand, are less prone to faults and power loss, reduce electricity thefts and air pollution, extends life of equipment etc. This bidirectional grid with integrated communication system, highly efficient sensors and measuring units, advanced components and control methods, decentralized generation and smart distribution is called smart grid. They are self-healing, have efficient OMS, reduce greenhouse gas emission and focus on improving the PQ. Their main objective is smart and optimal utilization of all available resources.
The major characteristics of smart grid are -It allows informed participation of consumers to modify their use and purchase of electricity and monitor their consumption pattern. It allows use of all generation and storage options i.e. centralized as well as distributed (incorporates renewable energy resources also). It enables new services, markets and products. Provides real time pricing. It improves power quality by self-healing, load forecasting, fault prediction and control and monitoring of frequency. Asset utilization and operating efficiency is optimized by the use of latest technologies.

II. Architecture of Smart Grid
The bidirectional smart grid is composed of a smart generating system, smart transmission and smart distribution system and an advanced metering infrastructure with highly efficient meter data management system. Below figure shows the basic architecture of smart grid. @ IJTSRD | Unique Reference Paper ID -IJTSRD21344 | Volume -3 | Issue -2 | Jan-Feb 2019 Page: 336

B. Neighborhood Area Network
The function of Neighborhood Area Network (NAN) is to communicate the information collected by smart meters to central controller. The NANs may contain few hundreds of smart meters deployed in HANs. Smart meters are linked with different gateways through NANs. The coverage region of NANs is around 1-10 square miles.

IV. Communication Standards for Wireless Sensor Networks
The address oriented traditional communication network is based on dedicated physical and network identification of transmitter and receiver. As WSNs include redundant nodes to compensate for degraded signal strengths of the nodes or node failure, in a WSN, the specific address of a node is of least concern. Measured values must be communicated between nodes irrespective of an address of the node. Thus, WSN communication is data oriented. WSN communication architecture design entails a conceptual paradigm shift based on applications. The communication standards applicable for WSN are described as below

A. Zigbee
Zigbee is based on IEEE 802.15.4 standard. It is an energy proficient short range wireless communication technology. It functions in the ISM (Industrial, scientific and medical) band which is allocated for industrial, scientific and medical applications. Zigbee operates in the band of 2.4 GHz, 868 and 928 MHz with full duplex wireless data transmission. IEEE 802.15.4 standard describes physical layer and media access layer and Zigbee Alliance has expanded the configuration of an application layer and network layer. The maximum throughput achievable by Zigbee is 250 Kbps. Zigbee can play an imperative role in operation and maintenance of power grid, data accumulation, parameter measurement, security, monitoring and consumer interface.

D. Z-Wave
Z-Wave protocol is specifically designed for smart home applications. It can be adopted in Home area networks of smart grid. Z-Wave is a low data rate, short range radio frequency mesh networking standard operating on 908 MHz band. The maximum coverage area is 30 m indoor. It does not require central coordinator but employs master and slave nodes. It can support 232 devices. The data rate is from 9.6 Kbps to 40 Kbps.

Conclusion
In this paper we presented the different communication protocols that can be used for smart grids. The method to be used mainly depends on the various parameters such as distance, speed, cost etc. There still many protocols which are used for the smart grid application and are mainly depending on the fried such as automation, robotics medical etc.