A Novel EMI Attack Exploiting the Control Vulnerability of Photovoltaic Inverters

Abstract

With the rapid development of distributed generation(DG), the penetration rate of photovoltaics(PVs) in the power grid continues to increase. Therefore, various security issues faced by PV inverters have also become a major challenge to ensure the stability of the power grid.Due to the complex and open environment of PVs, attackers are more likely to access key devices such as grid-tied inverters, thereby causing damage to the entire power grid. Taking advantage of the above characteristics, this paper proposes a novel electromagnetic interference(EMI) attack against inverters, instead of cyber attacks that have been explored well in many other research works. It injects a bias signal into the PV inverter sensor through EMI, so as to change the sensor value finally transmitted to the controller. An attacker can tamper with the sensor value in this way. This paper also analyzes the vulnerability in the inverter control algorithm, and exploits the vulnerability to cause damage to the inverter through EMI attacks.The attack was verified on a commercial inverter from Texas Instruments. We present the induced DC voltage offset corresponding to different EMI frequencies of different sensors to demonstrate that EMI attacks can independently control different sensors on the inverter. In addition, we also analyze the inverter control algorithm and the possible consequences of attacks, further evaluate the consequences of the attack through simulations (we do simulations instead of real device tests to ensure safety). And the results show that this novel attack can shut down/burn the PV inverter.