Energy

Estimation of Cyclable Lithium for Li-ion Battery State-of-Health Monitoring

Park, Saehong
Zhang, Dong
Klein, Reinhardt
Moura, Scott
2021

State of health (SOH) estimation for Li-ion batteries enables high-fidelity monitoring and high-performance in advanced battery management systems for applications such as mobile devices, electrified transportation, and energy storage. In order to achieve accurate SOH information, this paper improves the output voltage prediction by considering state-dependent parameters for a reduced-order electrochemical model. In addition, the SOH information is defined as the total moles of lithium in both solid-phase and electrolyte-phase, which directly affects the initial conditions of the...

Integrating Electrochemical Modeling with Machine Learning for Lithium-Ion Batteries

Tu, Hao
Moura, Scott
Fang, Huazhen
2021

Mathematical modeling of lithium-ion batteries (LiBs) is a central challenge in advanced battery management. This paper presents a new approach to integrate a physics-based model with machine learning to achieve high-precision modeling for LiBs. This approach uniquely proposes to inform the machine learning model of the dynamic state of the physical model, enabling a deep integration between physics and machine learning. We propose two hybrid physics-machine learning models based on the approach, which blend a single particle model with thermal dynamics (SPMT) with a feedforward neural...

A Vector Auto-Regression Based Forecast of Wind Speeds in Airborne Wind Energy Systems

Keyantuo, Patrick
Dunn, Laurel N.
Haydon, Ben
Vermillion, Christopher
Chow, Fotini K.
Moura, Scott J.
2021

This paper presents two wind energy forecast methods for control of an airborne wind energy system (AWE). The primary objective is to maximize the energy production of the AWE system under a spatio-temporally varying environment with uncertainty in the future wind speed. The controller for the AWE system is formulated as a model predictive controller (MPC). We employ data-driven models to generate probabilistic forecasts of the wind using vector auto-regression (VAR) and time-of-day forecasts. Bayesian optimization is employed to find the optimum of an unknown and expensive to evaluate...

Electrode-Level State Estimation in Lithium-Ion Batteries via Kalman Decomposition

Zhang, Dong
Couto, Luis D.
Moura, Scott J.
2021

Lithium-ion battery electrode-level online state estimation using high-fidelity nonlinear electrochemical models remains a key challenge. This is particularly due to weak observability inherited from the complex model structure, even for reduced-order electrochemical models. This letter presents a systematic and rigorous strategy to analyze the local observability of a single particle model (SPM) with both electrodes, which is commonly known to be locally unobservable from current-voltage measurements. Estimating the essential states, e.g., state of charge (SOC) and solid-phase lithium...

Battery Internal Temperature Estimation via a Semilinear Thermal PDE Model

Zhang, Dong
Dey, Satadru
Tang, Shu-Xia
Drummond, Ross
Moura, Scott J.
2021

Accurate Lithium-ion (Li-ion) battery internal temperature information enables high-fidelity monitoring and safe operation in battery management systems, thus prevents thermal faults that could cause catastrophic failures. This paper proposes an online temperature estimation scheme for cylindrical Li-ion batteries based on a one-dimensional semilinear parabolic partial differential equation (PDE) model subject to in-domain and output uncertainties, using temperature measurements at the battery surface only. The thermal state observer design exploits PDE backstepping method, with a mild...

Dynamic Coverage Meets Regret: Unifying Two Control Performance Measures for Mobile Agents in Spatiotemporally Varying Environments

Haydon, Ben
Mishra, Kirti D.
Keyantuo, Patrick
Panagou, Dimitra
Chow, Fotini
Moura, Scott
Vermillion, Chris
2021

Numerous mobile robotic applications require agents to persistently explore and exploit spatiotemporally varying, partially observable environments. Ultimately, the mathematical notion of regret, which quite simply represents the instantaneous or time-averaged difference between the optimal reward and realized reward, serves as a meaningful measure of how well the agents have exploited the environment. However, while numerous theoretical regret bounds have been derived within the machine learning community, restrictions on the manner in which the environment evolves preclude their...

Generalized Empirical Regret Bounds for Control of Renewable Energy Systems in Spatiotemporally Varying Environments

Haydon, Ben
Cole, Jack
Dunn, Laurel
Keyantuo, Patrick
Chow, Fotini K.
Moura, Scott
Vermillion, Chris
2022

This paper focuses on the empirical derivation of regret bounds for mobile systems that can optimize their locations in real-time within a spatiotemporally varying renewable energy resource. The case studies in this paper focus specifically on an airborne wind energy system, where the replacement of towers with tethers and a lifting body allows the system to adjust its altitude continuously, with the goal of operating at the altitude that maximizes net power production. While prior publications have proposed control strategies for this problem, often with favorable results based on...

Exploration vs. Exploitation in Airborne Wind Energy Systems via Information-Directed Sampling Control

Goujard, Guillaume
Keyantuo, Patrick
Badoual, Mathilde
Moura, Scott J.
2022

Airborne Wind Energy systems (AWEs) are an emerging wind generation technology. They differ from conventional turbines in that they are attached to the ground by a tether and can evolve from low to high altitudes (approx. 1km). Informed altitude control of AWEs is key to track favorable wind speed and maximize power output in a time-varying and partially-observable environment. Leveraging recent advances in Multi-Armed Bandit problems, we recursively estimate the wind profile distribution and use the residuals to fit the noise covariance in an online fashion. This filtering approach paves...

Investigating the “Whole-Life Performance” of Representative Profile Extraction for Microgrid Planning

Xie, Linfeng
Ju, Yi
Wang, Zhe
Su, Zhihan
Moura, Scott
Lin, Borong
2023

Numerous innovations emerge for decarbonization in energy systems. Practitioners and policymakers look for reliable methodology to evaluate their actual contributions unbiasedly. Usually, such evaluation starts from extracting a collection of profiles, which represents the actual application scenarios and certainly influences the ultimate results. However, such a fundamental task has seemingly long been treated casually. Limited literature on this topic rarely extends their attention beyond clustering methods. In this paper, we present mainly three innovations. First, we make a systematic...

Improved Power Grid Stability and Efficiency with a Building-Energy Cyber-Physical System

Piette, Mary Ann
Sohn, Michael
Bayen, Alexandre M.
2009

This position article outlines some challenges of demand response in the context of the power grid and its interaction with buildings. We describe significant issues in energy-efficient operation of buildings, in particular questions such as system reliability, risk management and environmental impact. We also outline a strategy for the development of new technologies for a cyber-physical infrastructure system that integrates management of smart buildings with management of the power grid. Specific emphasis is given to the interaction of physical and computational processes through sensing,...