Student: Sai Pushpak
Advisor: Umesh Vaidya
Title: Resiliency and Robust Control of Power Networks Against Communication Channel Uncertainty
Abstract: Advancement in sensing Phasor Measurement Units (PMU) technology has lead to their wide usage for real-time monitoring and feedback control in a networked power system. One of the important applications of PMU measurements is in the design of a wide area controller to damp the inter-area oscillations in a power network. The PMU measurements and control inputs are transferred across distance over communication channels. These communication channels are subjected to a natural source of uncertainty such as packet-drops and delays or can be a target for cyber attack, where the attacker tampers with the data transmitted. In this work, we develop an unified system theoretic framework to analyze the vulnerability and design of robust mitigation strategies against various sources of uncertainties that arise in communication channels. These communication channel uncertainties are modeled as stochastic random variables. We have developed systematic results based on Linear Matrix Inequalities (LMI) and optimization for stochastic stability verification and robust control design of power networks in the presence of communication channel uncertainties. The results provide guidelines for the maximum tolerable channel uncertainty and sensor/actuator noise for the purpose of wide area control. Application of the proposed framework is demonstrated on the IEEE 39 bus system. Apart from the stochastic stability verification and robust control design, the proposed framework is also used to rank order PMU measurements based on their criticality for wide area control.