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Relay Network is most suited wireless communication technique for future Smart Grid, because it has a lot of advantages such as reliability against failures and offers redundancy, self-configuring and self-healing. For example if one nod or path is blocked, it can find a neighbour node, by different algorithms schemes. The purpose of this paper is to simulate wireless relay channel model in presence of impulse noise and computing the BER performance of channel data. It makes to be useful for a designer to predicting error and behaviour of a channel for optimum design, to be able choose a robust channel.

The role that a Smart Substation Automation System (SSAS) plays as a bridge between a power system and the Smart Grid (SG) is very important for the stable application of a SG in the field. A variety of SG functions affect the power system, and as the number of these functions increases, the influence of the SG in a power system increases as well. Therefore, SSAS will become increasingly important for the application of SG in power systems. Most reported work on this subject has been on the implementation of conventional protection and automation schemes in the IEC 61850 environment. However, these studies did not indicate the importance of a SSAS or define a SSAS in the context of a SG; a conceptually ambiguously SSAS formed the basis on which their algorithms and systems were proposed. In order to clarify this ambiguity, this paper proposes both a definition and a concept of SSAS. This paper proposes the concept from two perspectives; the first perspective addresses the change required in a powerful new system environment that considers SG. The second perspective involves the use of smart functions that enhance the operational efficiency of a SSAS. The concept of the system environment takes into consideration the type of communication network, network topology, protocol, cyber security, IEDs and other automation devices, and the influence of Distributed Generation (DG). In addition, the concept of smart functions takes into account optimized operation, protection, restoration, a distributed control operation, and microgrid operation.

An IEC 61850 based Substation Automation System (SAS) changed existing substation environment to a digital system environment using Ethernet based communication network and microprocessor based IED. Although, system environment has changed to a new environment, but operation and protection schemes have not taken full advantage of the new system environment. In this paper, a Multi-type Protection IED (MPI) is proposed that can be remotely change its protection type without IED reboot or field control. The proposed MPI is designed by using SCL (Substation Configuration Language) engineering based IED and a file transfer service in IEC 61850. The proposed MPI remotely receives a new SCD (Substation Configuration Description) file from station and changes protection type through a parsing of the received SCD file, destruction of existing logical node memories and threads for protection, initialization of new memories for new protection elements, and start of threads for new protection components according to parsing results which are names of logical nodes without recompile or system reboot. Benefits of such MPI are various. For example, a substation operator doesn't need to consider a type of protection IED when substation is designed because the MPI can be set remotely to any type at the station. The number of backup IEDs can be reduced because MPI can be changed to protection IED of any type. A substation operator can reconstruct configuration of protection IEDs suitable for a special or the worst case. The proposed MPI was implemented by SISCO library and Windows programming. For testing the performance of the proposed MPI, two case studies that change the logical nodes of an MPI without reboot and that makes an MPI as a backup IED when primary IED fails are considered. Test results rom these case studies are presented.