976 citations · 2.8k across the 41 of their papers we have counts for
28 papers · 1 filter
Automated Lyapunov Analysis of Primal-Dual Optimization Algorithms: An Interpolation Approach
Bryan Van Scoy, John W. Simpson-Porco, Laurent Lessard
Primal-dual algorithms are frequently used for iteratively solving large-scale convex optimization problems. The analysis of such algorithms is usually done on a case-by-case basis…
Low-Gain Stabilizers for Linear-Convex Optimal Steady-State Control
John W. Simpson-Porco
We consider the problem of designing a feedback controller which robustly regulates an LTI system to an optimal operating point in the presence of unmeasured disturbances. A genera…
Diagonal Stability of Systems with Rank-1 Interconnections and Application to Automatic Generation Control in Power Systems
John W. Simpson-Porco, Nima Monshizadeh
We study a class of matrices with a rank-1 interconnection structure, and derive a simple necessary and sufficient condition for diagonal stability. The underlying Lyapunov functio…
Low-Gain Stability of Projected Integral Control for Input-Constrained Discrete-Time Nonlinear Systems
John W. Simpson-Porco
We consider the problem of zeroing an error output of a nonlinear discrete-time system in the presence of constant exogenous disturbances, subject to hard convex constraints on the…
A Dynamic Stability and Performance Analysis of Automatic Generation Control
John W. Simpson-Porco
Automatic generation control (AGC) is one of the most important coordinated control systems present in modern interconnected power systems. Despite being heavily studied, no interc…
On Stability of Distributed-Averaging Proportional-Integral Frequency Control in Power Systems
John W. Simpson-Porco
Distributed consensus-based controllers for optimal secondary frequency regulation of microgrids and power systems have received substantial attention in recent years. This paper p…
Analysis and Synthesis of Low-Gain Integral Controllers for Nonlinear Systems
John W. Simpson-Porco
Relaxed conditions are given for stability of a feedback system consisting of an exponentially stable multi-input multi-output nonlinear plant and an integral controller. Roughly s…
Quadratic Performance Analysis of Secondary Frequency Controllers
Bala Kameshwar Poolla, John W. Simpson-Porco, Nima Monshizadeh +1
This paper investigates the input-output performance of secondary frequency controllers through the control-theoretic notion of norms. We consider a quadratic objective accou…
Towards robustness guarantees for feedback-based optimization
Marcello Colombino, John W. Simpson-Porco, Andrey Bernstein
Feedback-based online optimization algorithms have gained traction in recent years because of their simple implementation, their ability to reject disturbances in real time, and th…
Optimal Steady-State Control for Linear Time-Invariant Systems
Liam S. P. Lawrence, Zachary E. Nelson, Enrique Mallada +1
We consider the problem of designing a feedback controller that guides the input and output of a linear time-invariant system to a minimizer of a convex optimization problem. The s…
Linear-Convex Optimal Steady-State Control
Liam S. P. Lawrence, John W. Simpson-Porco, Enrique Mallada
We consider the problem of designing a feedback controller for a multivariable linear time-invariant system which regulates an arbitrary system output to the solution of an equalit…
Resilient Estimation and Control on -Nearest Neighbor Platoons: A Network-Theoretic Approach
Mohammad Pirani, Ehsan Hashemi, Baris Fidan +3
This paper is concerned with the network-theoretic properties of so-called -nearest neighbor intelligent vehicular platoons, where each vehicle communicates with vehicles, b…
Input-Output Performance of Linear-Quadratic Saddle-Point Algorithms with Application to Distributed Resource Allocation Problems
John W. Simpson-Porco, Bala Kameshwar Poolla, Nima Monshizadeh +1
Saddle-point or primal-dual methods have recently attracted renewed interest as a systematic technique to design distributed algorithms which solve convex optimization problems. Wh…
Equilibrium-Independent Dissipativity with Quadratic Supply Rates
John W. Simpson-Porco
Equilibrium-independent dissipativity (EID) is a recently introduced system property which requires a system to be dissipative with respect to any forced equilibrium configuration.…
High-voltage solution in radial power networks:Existence, properties and equivalent algorithms
Krishnamurthy Dvijotham, Enrique Mallada, John W Simpson-Porco
The AC power flow equations describe the steady-state behavior of the power grid. While many algorithms have been developed to compute solutions to the power flow equations, few th…
System-Theoretic Performance Metrics for Low-Inertia Stability of Power Networks
Mohammad Pirani, John W. Simpson-Porco, Baris Fidan
As bulk synchronous generators in the power grid are replaced by distributed generation interfaced through power electronics, inertia is removed from the system, prompting concerns…
A Theory of Solvability for Lossless Power Flow Equations -- Part II: Conditions for Radial Networks
John W. Simpson-Porco
This two-part paper details a theory of solvability for the power flow equations in lossless power networks. In Part I, we derived a new formulation of the lossless power flow equa…
A Theory of Solvability for Lossless Power Flow Equations -- Part I: Fixed-Point Power Flow
John W. Simpson-Porco
This two-part paper details a theory of solvability for the power flow equations in lossless power networks. In Part I, we derive a new formulation of the lossless power flow equat…
Lossy DC Power Flow
John W. Simpson-Porco
The DC Power Flow approximation has been widely used for decades in both industry and academia due to its computational speed and simplicity, but suffers from inaccuracy, in part d…
A Graph Theoretic Approach to the Robustness of k-Nearest Neighbor Vehicle Platoons
Mohammad Pirani, Ehsan Hashemi, John W. Simpson-Porco +2
We consider a graph theoretic approach to the performance and robustness of a platoon of vehicles, where each vehicle communicates with its -nearest neighbors. In particular, we…
Distributed Monitoring of Voltage Collapse Sensitivity Indices
John W. Simpson-Porco, Francesco Bullo
The assessment of voltage stability margins is a promising direction for wide-area monitoring systems. Accurate monitoring architectures for long-term voltage instability are typic…
Voltage stress minimization by optimal reactive power control
Marco Todescato, John W. Simpson-Porco, Florian Dörfler +2
A standard operational requirement in power systems is that the voltage magnitudes lie within prespecified bounds. Conventional engineering wisdom suggests that such a tightly-regu…
Improving performance of droop-controlled microgrids through distributed PI-control
Emma Tegling, Martin Andreasson, John W. Simpson-Porco +1
This paper investigates transient performance of inverter-based microgrids in terms of the resistive power losses incurred in regulating frequency under persistent stochastic distu…
Voltage Stabilization in Microgrids via Quadratic Droop Control
John W. Simpson-Porco, Florian Dorfler, Francesco Bullo
We consider the problem of voltage stability and reactive power balancing in islanded small-scale electrical networks outfitted with DC/AC inverters ("microgrids"). A droop-like vo…