# Enhancing Cybersecurity in Smart Grids: False Data Injection and Its Mitigation
## 1 Introduction  
The traditional electricity grid system of the 20 th century is insufficient to meet today's needs. Novel technologies such as Electric Vehicles (EVs), smart inverters and renewable energy-based generators are continually being deployed [1]. They change power system operation paradigms, introduce bi-lateral power flow and create a dynamic operation structure which was not originally envisioned [2]. To tackle these issues, power systems are equipped with more measurement, communication, and control capabilities. More accurate information about the grid's current state can be obtained in this fashion, and a decision can be made in pseudo-real time [3]. This modern power system structure is collectively called the Smart Grid (SG). There are many definitions of SG concept, such as \"A network where all consumers can reach efficient, cheap, accessible, and reliable energy by using control and communication technologies\" [4]. Alternatively, SG is a system that is adaptive, reliable, interactive and allows for renewable energy sources integration and optimization [5, 6]. In addition to these definitions, the National Institute of Standards and Technology (NIST) gives a high-level perspective and classifies SGs. Moreover, application characteristics and requirements of SG infrastructure are divided into different layers [7]:  
* Application;
* Security;* Communication;
* Control of Power;
* Power system. As shown in Figure 1, SGs are divided into generation, transmission, distribution, service providers, and consumers. According to fields of study, control of power and communication technologies should solve possible problems encountered in the SG [7]. The working principles of all power electronics elements integrated into the network should be well analysed to achieve effective SG system [8]. Stable and efficient transmission of energy to the end customer is crucial for a reliable network implementation. If it is made, energy efficiency and local renewable energy usage will increase, and the ideal grid system will be realised by reducing the transmission losses [9]. Considering the vast geographical span of SGs and the number of devices they host, it is inevitable that the cybersecurity vulnerabilities become more prevalent than the other. Furthermore, the consequences of security breaches in such critical infrastructure will have significant ramifications, as all organizations with energy-providing authorities agree [10]. According to [11], SG can be considered an electrical system that uses cyber secure information and communication technologies. The system works to obtain a safe, reliable, and efficient computational intelligence system integrated with electricity transmission, generation, and distribution substations. It is possible to classify cybersecurity into three systems, as shown below in Figure 2: Smart energy, information, and communication systems listed under smart infrastructure system. They must work simultaneously with the smart management system and support its protection system [12]. Existing cybersecurity solutions have difficulties in meeting the needs of SG communication systems. When recent research is examined, it can be understood that traditional cybersecurity methods and algorithms have usually studied, and there are separate studies on power and communication regarding cyber risks. If critical systems such as the power system communication infrastructure have cybersecurity risks, that can have severe consequences and traditional risks are now included in risk assessments. However, SG communication systems security is a relatively new topic; few academic and experimental studies have been found [13]. Figure 1: NIST SG Model. A general assessment of the vulnerabilities can split into five categories:  
* Interaction control framework security;
* Smart meter measurement security;
* Assessment of power system status security;
* Intelligent network communication convention security;
* Security analysis with SG simulation. Cybersecurity in SGs is an emerging field [14].