Publications by Martand Singhal

A note on efficient computation of privileged directions in modifier adaptation

Dominique Bonvin, Martand Singhal, Timm Faulwasser, Alejandro Gabriel Marchetti

In the presence of plant-model mismatch, the estimation of plant gradients is key to the performance of measurement-based iterative optimization schemes. However, gradient estimation requires time-consuming experiments, wherein the plant is sequentially pe ...

PERGAMON-ELSEVIER SCIENCE LTD2020

On enforcing the necessary conditions of optimality under plant-model mismatch - What to measure and what to adapt?

Martand Singhal

Industrial processes are run with the aim of maximizing economic profit while simultaneously meeting process-critical constraints. To this end, model-based optimization can be performed to ensure optimal plant operations. Usually, inevitable model inaccura ...

EPFL2018

Active directional modifier adaptation for real-time optimization

Dominique Bonvin, Timm Faulwasser, Martand Singhal

2018

Active Directional Modifier Adaptation with Trust Region - Application to Energy-Harvesting Kites

Dominique Bonvin, Colin Neil Jones, Matthieu Jonin, Sanket Sanjay Diwale, Martand Singhal

Many real-time optimization schemes maximize process performance by performing a model-based optimization. However, due to plant-model mismatch, the model-based solution is often suboptimal. In modifier adaptation, measurements are used to correct the mode ...

IEEE2018

Adaptation strategies for tracking constraints under plant-model mismatch

Dominique Bonvin, Timm Faulwasser, Martand Singhal

Optimal operating conditions for a process plant are typically obtained via model based optimization. However, due to modeling errors, the operating conditions found are often sub-optimal or, worse, they can violate critical process constraints. Hence, mod ...

ELSEVIER SCIENCE BV2018

Enforcing Model Adequacy in Real-Time Optimization via Dedicated Parameter Adaptation

Dominique Bonvin, Martand Singhal, Afaq Ahmad

Iterative real-time optimization schemes that employ modifier adaptation add bias and gradient correction terms to the model that is used for optimization. These affine corrections lead to meeting the first-order necessary conditions of optimality of the p ...

ELSEVIER SCIENCE BV2018

Modifier adaptation with guaranteed feasibility in the presence of gradient uncertainty

Dominique Bonvin, Timm Faulwasser, Alejandro Gabriel Marchetti, Martand Singhal

In the context of real-time optimization, modifier-adaptation schemes use estimates of the plant gradients to achieve plant optimality despite plant-model mismatch. Plant feasibility is guaranteed upon convergence, but not at the successive operating point ...

Pergamon-Elsevier Science Ltd2017

Improved Directional Derivatives for Modifier-Adaptation Schemes

Dominique Bonvin, Timm Faulwasser, Alejandro Gabriel Marchetti, Martand Singhal

The modifier-adaptation methodology enables real-time optimization (RTO) of plant operation in the presence of considerable plant-model mismatch. It requires the estimation of plant gradients. Obtaining these gradients is expensive as it involves potential ...

2017

Real-Time Optimization Based on Adaptation of Surrogate Models

Dominique Bonvin, Timm Faulwasser, Alejandro Gabriel Marchetti, Martand Singhal

Recently, different real-time optimization (RTO) schemes that guarantee feasibility of all RTO iterates and monotonic convergence to the optimal plant operating point have been proposed. However, simulations reveal that these schemes converge very slowly t ...

Elsevier Science Bv2016

On Handling Cost Gradient Uncertainty in Real-Time Optimization

Dominique Bonvin, Timm Faulwasser, Martand Singhal

This paper deals with the real-time optimization of uncertain plants and proposes an approach based on surrogate models to reach the plant optimum when the plant cost gradient is imperfectly known. It is shown that, for processes with only box constraints, ...

2015