Designing an Intrusion Detection for an Adjustable Speed Drive System Controlling a Critical Process

In this article, we address the cyber-security problem of industrial control systems (ICSs) when their sensor measurements may be compromised due to an attacker who has intercepted those via a network. We introduce general-purpose method “Dynamic Watermarking (DW)” detect potential cyber-intrusions on speed within systems, which deploy adjustable drive (ASD) critical process. The DW is injecting random private low-amplitude signal with zero mean Gaussian distribution, “watermark”, into one input phase voltages powering ASD system. watermark propagates through system including pulse width modulation (PWM) power conversion stage and motor, then ultimately appears in measurements. By deploying two statistical tests proper thresholds, can or unobservable cyber-attacks such as replay attacks false data injection (FDIA). tested laboratory-scale experimentally protect against cyber-intrusions. This system, powered by commercial PWM operating at 208 V, 3-phase, 3.7 kW, served our experimental platform.