Sivaranjani Seetharaman

Purdue University | Purdue

We present a conic sector theorem for linear parameter varying (LPV) systems in which the traditional definition of conicity is violated for certain values of the parameter. We show that such LPV systems can be defined to be conic in an average sense if the parameter trajectories are restricted so that the system operates with such values of the pa...

Recent advances in distribution-level phasor measurement unit (D-PMU) technology have enabled the use of voltage phase angle measurements for direct load sharing control in distribution-level microgrid interconnections with high penetration of renewable distributed energy resources (DERs). In particular, D-PMU enabled voltage angle droop control ha...

We consider the problem of designing distributed controllers to guarantee dissipativity of a networked system comprised of dynamically coupled subsystems. Additionally, we require that the control synthesis is carried out locally at the subsystem-level, without explicit knowledge of the dynamics of other subsystems in the network. We solve this pro...

We consider the problem of identifying a dissipative linear model of an unknown nonlinear system that is known to be dissipative, from time domain input-output data. We first learn an approximate linear model of the nonlinear system using standard system identification techniques and then perturb the system matrices of the linear model to enforce d...

We consider the problem of identifying a dissipative linear model of an unknown nonlinear system that is known to be dissipative, from time-domain input–output data. We first learn an approximate linear model of the nonlinear system using standard system identification techniques and then perturb the system matrices of the linear model to enforce d...

This paper considers the problem of characterizing the stability region of a large-scale networked system comprised of dissipative nonlinear subsystems, in a distributed and computationally tractable way. One standard approach to estimate the stability region of a general nonlinear system is to first find a Lyapunov function for the system and char...

The electric grid is a key enabling infrastructure for the ambitious transition towards carbon neutrality as we grapple with climate change. With deepening penetration of renewable resources, the reliable operation of the electric grid becomes increasingly challenging. In this paper, we present PSML, a first-of-its-kind open-access multi-scale time...

The electrification of heavy-duty vehicles (HDEVs) is a nascent and rapidly emerging avenue for decarbonization of the transportation sector. In this paper, we examine the impacts of increased vehicle electrification on the power grid infrastructure, with particular focus on HDEVs. We utilize a synthetic representation of the 2000-bus Texas transmi...

The electrification of heavy-duty vehicles (HDEVs) is a nascent and rapidly emerging avenue for decarbonization of the transportation sector. In this paper, we examine the impacts of increased vehicle electrification on the power grid infrastructure, with particular focus on HDEVs. We utilize a synthetic representation of the 2000-bus Texas transmi...

Demand response (DR) is gaining attention to enhance the grid reliability with deep renewable energy penetration, as the grid recently experienced in Texas during the Feb 2021 winter storm. While studies demonstrated benefits of DR in mitigating price volatility, there is limited work considering the choice of locations for DR. We reveal that small...

In the article entitled “Distributed synthesis of local controllers for networked systems with arbitrary interconnection topologies” published in the IEEE Transactions on Automatic Control , vol. 66, pp. 683–698, 2021, there were some missing terms in Lemma 1 and the definition of the messenger matrices. Here, we include these terms and suitably...

The electric grid is a key enabling infrastructure for the ambitious transition towards carbon neutrality as we grapple with climate change. With deepening penetration of renewable energy resources and electrified transportation, the reliable and secure operation of the electric grid becomes increasingly challenging. In this paper, we present PSML,...

We consider the problem of guaranteeing that the transient voltages and currents stay within prescribed bounds in Direct Current (DC) microgrids, when the controller does not have access to accurate system dynamics due to the load being unknown and/or time-varying. To achieve this, we propose an optimization based controller design using control ba...

We consider the problem of guaranteeing that the transient voltages and currents stay within prescribed bounds in Direct Current (DC) microgrids, when the controller does not have access to accurate system dynamics due to the load being unknown and/or time-varying. To achieve this, we propose an optimization based controller design using control ba...

We consider the problem of designing distributed controllers to stabilize a class of networked systems, where each subsystem is dissipative and designs a reinforcement learning based local controller to maximize an individual cumulative reward function. We develop an approach that enforces dissipativity conditions on these local controllers at each...

Recent advances in distribution-level phasor measurement unit (D-PMU) technology have enabled the use of voltage phase angle measurements for direct load sharing control in distribution-level microgrid interconnections with high penetration of renewable distributed energy resources (DERs). In particular, D-PMU enabled voltage angle droop control ha...

We consider the problem of designing distributed controllers to stabilize a class of networked systems, where each subsystem is dissipative and designs a reinforcement learning based local controller to maximize an individual cumulative reward function. We develop an approach that enforces dissipativity conditions on these local controllers at each...

This paper studies a co-design of solar generation-based nano-grid and water treatment in remote areas. The goal is to provide the minimum essential drinking water and electricity needs to communities in remote, underdeveloped regions such as Colonias in South Texas at the United States-Mexico border. It is shown that a portable nanofiltration trea...

The novel coronavirus disease (COVID-19) has rapidly spread around the globe in 2020, with the US becoming the epicenter of COVID-19 cases since late March. As the US begins to gradually resume economic activity, it is imperative for policymakers and power system operators to take a scientific approach to understanding and predicting the impact on...

The novel coronavirus disease (COVID-19) has rapidly spread around the globe in 2020, with the U.S. becoming the epicenter of COVID-19 cases since late March. As the U.S. begins to gradually resume economic activity, it is imperative for policymakers and power system operators to take a scientific approach to understanding and predicting the impact...

The novel coronavirus disease (COVID-19) has rapidly spread around the globe in 2020, with the U.S. becoming the epicenter of COVID-19 cases and deaths in late March. In this context, there have been federal and state-level policy interventions aiming at mitigating the public health risks of this pandemic. These social distancing and work-from-home...

We consider the problem of designing distributed controllers to guarantee dissipativity of a networked system comprised of dynamically coupled subsystems. We require that the control synthesis is carried out locally at the subsystem-level, without explicit knowledge of the dynamics of other subsystems in the network. We solve this problem by derivi...

We consider the problem of designing distributed controllers to ensure passivity of a large-scale interconnection of linear subsystems connected in a cascade topology, where the control design process needs to be carried out locally at the subsystem-level with no direct knowledge of the dynamics of other subsystems in the interconnection. We presen...

We consider the problem of guaranteeing transient stability in angle droop controlled microgrid networks where voltage angle measurements from phasor measurement units (PMUs) may be lost. In the event of PMU measurement loss at some microgrids, the network may become unstable if there is a mismatch between load and power generation. To address this...

We synthesize performance-aware safe cruise control policies for longitudinal motion of platoons of autonomous vehicles. Using set-invariance theories, we guarantee infinite-time collision avoidance in the presence of bounded additive disturbances, while ensuring that the length and the cruise speed of the platoon are bounded within specified range...

We present an approach to passivate a class of discrete time switched nonlinear systems under arbitrary switching. Using switched storage functions, we derive a linear matrix inequality condition for strict input passivity of discrete time switched nonlinear systems. When the switched system is non passive, we design a state feedback controller to...

We design distributed control laws (to be followed by individual vehicles) that ensure the localization of shock waves (stop-and-go waves) in transportation networks to specified sections of the transportation network, and their elimination within a guaranteed period of time.

We propose novel fuel-optimal control algorithms for large-scale traffic flows that utilize measurements from V2V and V2I networks to localize shock waves to a small region around their origin, and eliminate them within a specified period of time.

We present a control strategy for localization and attenuation of disturbances in transportation systems. Sudden and large disturbances in a transportation network can lead to the creation and propagation of shock waves which spread throughout the system causing jams and decreasing system throughput. By considering the Cell Transmission Model of tr...

The integration of communication infrastructure into the smart grid has made available real-time measurements from around the network and provided opportunities for better control paradigms. However, the transmission of power system measurements and control signals via a communication network introduces issues like delays and packet dropouts that c...

This paper presents a networked control systems (NCS) framework for the coordinated control of distributed generation sources in smart power grids. The system measurements are transmitted to the controller through a realtime communication network. The effects of delays and packet dropouts due to the communication network are modeled and networked c...

This paper presents a networked control systems (NCS) framework for wide area monitoring control of smart power grids. We consider a scenario in which wide area measurements are transmitted to controllers at remote locations. We model the effects of delays and packet dropouts due to limited communication capabilities in the grid. We also design a r...

In the design of complex quantum systems like ion traps for quantum computing, it is usually desired to stabilize a particular system state or make the system state track a desired trajectory. Several control theoretical approaches based on feedback seem attractive to solve such problems. But the uncertain dynamics introduced by measurement on quan...