# Smart Grid Fault Mitigation and Cybersecurity with Wide-Area Measurement Systems: A Review
## 1 Introduction
### Definitions of WAMS  
Multiple definitions of WAMS have been published, and many studies have been conducted on their vast potential and practical results. In a SCADA system, monitoring and control responsibilities are not provided in a probabilistic power reliability assessment. In WAMS, by contrast, reliability assessments have shown that successful operation was more certain when WAMS elements were deployed and utilized optimally in a power system network [12]. [PERSON] et al. deployed PMUs in the Jordanian National Grid and developed a WAMS architecture. They defined a WAMS as a network of PMUs and components that improves the situational awareness of a power system network for real-time monitoring and control [10]. PMUs, which make up the bulk of a WAMS, serve as connecting links when synchronized with a satellite-based Global Positioning System (GPS) [5]. Traditionally, WAMS that differ in certain components are deployed to increase the operational awareness of the system [21]. The integrity of the energy system is prioritized in these designs, and some research has even extended the WAMS infrastructure to under-frequency load-shedding schemes [22]. Researchers widely agree that any power system network, including those with WAMS technology, can be considered a smart grid even if they retain certain old, outdated components that are not hallmarks of modern smart grid networks [4; 5]. WAMS was defined by [PERSON] et al. as an enabling technology that includes PMUs as measuring devices coupled with supporting communication infrastructure like phasor data controllers (PDCs) [1]. However, their study posited this definition before going on to suggest that a combination of a PMU and enabling information infrastructure is termed Synchrophasor Measurement Technology (SMT) [1]. In contrast, some studies have found SMT a component of WAMS infrastructure instead. Numerous research studies on European energy systems have highlighted the integration of smart systems into aging infrastructure, including SCADA and energy management systems (EMS) alongside PMUs to form WAMS [3; 4; 5; 6; 8; 14; 21; 23; 24; 25; 26]. In their study, [PERSON] et al. included PDCs, which are designed to transmit data collected from the PMUs on the lines and the different interconnected units in the energy infrastructure [22]. All of these become imperative to articulate components that properly define a WAMS infrastructure and assess the position of numerous researchers on the advantages of these technologies in the WAMS infrastructure [12; 18; 19; 20; 27]. SMT consists of several arrays of PMUs on the grid and the PDCs whose role is to aggregate the data collected by the PMUs interconnected across the energy infrastructure [3; 10]. The similarity in the components led [PERSON] et al. to conclude that SMT is synonymous with WAMS [11]. Others disagree, as SMT includes data collection PMUs like WAMS, but an absence of communication infrastructure makes SMT fundamentally different [18]. Therefore, the integration of SMTs, including PMUs and PDCs, and a proper communication infrastructure is regarded as a WAMS. The definition of WAMS becomes imperative for a proper analysis of the development of technology through the integration of multiple advances in the modern world of technology attempting to increase the volume of data collected, synchronized, and communicated to Energy Control Centers (ECCs) (as shown in Table 1) [3; 4; 5; 6; 14; 21; 24; 25; 28; 29; 30]. The main responsibility of WAMS infrastructure is to boost the real-time awareness of the power system network [18; 24; 25]. The observability and monitoring potential of WAMS cannot properly achieve the system's overall goal when proper communication infrastructure is absent [25]. This review shows the progression from SCADA infrastructure to modern applications of WAMS in increasing the operability of the energy management system following the recent deployment of artificial intelligence (AI) in real-time awareness, control, and efficiency enhancement [34].