Security of Electric Vehicle Charging Infrastructure

In recent years, the boundaries between the physical and the digital world have become increasingly blurry. Nowadays, many digital systems interact in some way with the physical world. Large and complex cyber-physical systems, such as autonomous and electric vehicles, combine the physical and the digital world and enable interaction between those two domains. Usually, such systems are equipped with numerous sensors to measure physical quantities, such as temperature, pressure, light, and sound. These physical quantities are vital inputs for the computations and can influence the decision-making process of the system. At the same time, the computations can affect physical processes by controlling actuators that alter physical quantities. In other words, in a cyber-physical system, the physical world influences the digital world and vice versa. 

In the context of electric vehicles, various sensors are used to ensure the safety of the vehicle. Besides temperature sensors, current and voltage sensors constantly monitor the electricity flow during a fast-charging session to ensure that the battery is not overcharged and is operating within safe limits. The measurements are sent to the charging station, which can adjust the current flow depending on the battery temperature. This enables a balance between safety and the maximum charging performance. 

Due to the nature of analogue sensors, it is not easily possible to authenticate the physical quantity that triggered a stimulus. This is a major concern as the integrity of sensor measurements is critical to ensuring that a system behaves as intended, and a violation of this principle can have serious security, safety, and reliability consequences. 

Evaluation of Signal Injection Attacks Against Electric Vehicle Charging 

This project will investigate more sophisticated, active signal injection attacks that target not only the communication but also the various sensor systems. It will analyse how intentional electromagnetic interference can affect sensors such as voltage, temperature, and current sensors, and how manipulated measurements can violate the safety of the vehicle during the charging session. The first step will be to develop a battery charging testbed, which would allow evaluation of attacks in a controlled manner. This will be followed by the investigation of new techniques, eg conductive coupling, to inject malicious electromagnetic signals onto the target circuit. 

Security Analysis of DC Rapid Charging Standards with V2G Capabilities  

While past research has uncovered inherent flaws in the Combined Charging System (CCS), this project intends to extend research to other charging standards. Besides CCS, three other conductive DC rapid charging technologies exist — CHAdeMO, Tesla’s supercharger, and GB/T 20234. The main difference between these standards and CCS is the use of CAN for the charging communication rather than power-line communication. To further enhance driver convenience and improve Vehicle-2-Grid capabilities, wireless charging, which uses Wi-Fi for communication, has been developed. However, an initial security analysis of a wireless charging station has revealed that the wireless charging communication lacks sufficient protection mechanisms. Given the V2G capabilities of these charging standards and their importance for the stability of the power grid, the project will investigate the attack surface of these charging technologies on the physical layer and against active attacks.