## 3 Features and Advantages of Smart Grid  
A smart grid consists of many different state-of-the art information and communication technology (ICT) and sensory devices and offers a wide range of advantages to both the utilities and the customers, which are, for example [29; 30; 31; 32; 33; 34; 35], Lowering the utility bills; Reduction of the peak demand; Economic and job growth; Integration of more renewable energy resources; Self-governing control, which increases the system reliability; Enhancing capacity and efficiency; Enhanced resilience against malicious attacks; Integration of different types of energy storages including plug-in electric vehicles; The communication between the service provider and customers is two-way; Improved market efficiency; Better power quality and reliability; Better utilization of facilities and deferring building of new power stations; Empower predictive maintenance and self-curing; Accommodate of decentralized power generations; Automated maintenance and operation; Reduce GHG emission; Several varieties for consumer; Providing opportunities for new services, products and markets. The features of the SG which individuates itself from conventional grids, are the sophisticated devices that it uses and the services that it provides in return which are unattainable in conventional grid systems [28]. Some of the prominent features of the SG include:  
* AMI: Smart meters rigged with advanced communication protocols are utilized in SG to record energy consumption over an interval of an hour or less. AMI devices lay the foundation for SG. The functionalities of these meters include sending information to the utility for system monitoring and controlling, as well as for preparing financial statements for the customers [36]. The customers can monitor and adjust the energy consumption in real time. In addition, the remote operation capability of these meters allows the energy providers to control the customer loads in order to manage loads and demands. A metering system that includes the aforementioned features is called AMI. The benefits of AMI are shown in Figure 2[37]. * Smart Monitoring and Measurement: Measuring system parameters using sensors is very essential for monitoring, controlling and operating the system efficiently and reliably. Sensor networks equipped with communication protocols are widely used in measuring, monitoring and controlling the systems. Such systems include electrical, electro-mechanical, communications, and oil and gas, etc. [38]. Specifically, in [39], it was recommended to embed sensor networks into the power grids in order to monitor conditions such as the failure of conductors, hot spots, and acute mechanical circumstances in the power grids. Such networks along with the Internet of things (IOT) can certainly enhance the monitoring and controlling process of the physical and electrical conditions of the modern grid network in real time. Hence, a combination of sensor network and IOT in smart grid application will elevate the capability of the SG in determining the proper control steps that the system operators need to execute. * Phasor Measurement Unit (PMU): PMU is an advanced measuring instrument that is integrated with a widely available communication technology such as global positioning system (GPS). It has the capability to monitor and measure synchronized system parameters from different locations around the power network based on a common reference time. Such parameters include voltage constraints, low frequency oscillation, thermal constraints, frequency deviation etc. The system operators utilize such devices to collect high frequency sampled measurement data in order to identify the system status so that the system operator can initiate the protective/controlling measures quickly and dynamically [30]. The schematic diagram of the PMU is shown in Figure 3[40]. This device has been used for wide area monitoring system in many countries around the world. Such countries are China, France, Brazil, South Korea, Mexico, Japan, Norway, and USA [38].