Small-Sample-Learning-Based Lithium-Ion Batteries Health Assessment: An Optimized Ensemble Framework

IEEE Transactions on Industry Applications

Published On 2024/1/9

Machine Learning is widely studied in battery state of health (SOH) estimation due to its advantage in establishing the non-linear mapping between measurements and SOH. However, the requirement of a big dataset and the lack of robustness limit the practical application, especially in small sample learning. To tackle these challenges, an optimal ensemble framework called BaggELM (bagging extreme learning machine) is proposed for battery SOH estimation. Specifically, the required dataset is reduced by optimizing the input voltage and the hyperparameters of the BaggELM algorithm. Moreover, a statistical post-processing method is used to aggregate multiple ELMs, and the final estimate is determined by the maximum probability density value. As a result, the effects of random parameterization of ELM and the training data size on SOH estimation are suppressed, thus improving the robustness and accuracy of …

Journal

IEEE Transactions on Industry Applications

Published On

2024/1/9

Authors

Remus Teodorescu

Remus Teodorescu

Aalborg Universitet

Position

Professor at

H-Index(all)

104

H-Index(since 2020)

72

I-10 Index(all)

0

I-10 Index(since 2020)

0

Citation(all)

0

Citation(since 2020)

0

Cited By

0

Research Interests

Power Electronics

Smart Batteries

AI

University Profile Page

Xin Sui

Xin Sui

Aalborg Universitet

Position

H-Index(all)

14

H-Index(since 2020)

14

I-10 Index(all)

0

I-10 Index(since 2020)

0

Citation(all)

0

Citation(since 2020)

0

Cited By

0

Research Interests

Li-ion batteries

SOH estimation

RUL prediction

University Profile Page

Shan He

Shan He

Aalborg Universitet

Position

H-Index(all)

10

H-Index(since 2020)

10

I-10 Index(all)

0

I-10 Index(since 2020)

0

Citation(all)

0

Citation(since 2020)

0

Cited By

0

Research Interests

Grid-connected converter

DFIG

Multi-phase motor drive

Battery

Power-to-X

University Profile Page

Other Articles from authors

Shan He

Shan He

Aalborg Universitet

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Remus Teodorescu

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Remus Teodorescu

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Remus Teodorescu

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Aalborg Universitet

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Remus Teodorescu

Remus Teodorescu

Aalborg Universitet

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Remus Teodorescu

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Aalborg Universitet

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Remus Teodorescu

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Aalborg Universitet

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Remus Teodorescu

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Remus Teodorescu

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Aalborg Universitet

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Remus Teodorescu

Remus Teodorescu

Aalborg Universitet

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Remus Teodorescu

Remus Teodorescu

Aalborg Universitet

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Remus Teodorescu

Remus Teodorescu

Aalborg Universitet

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Remus Teodorescu

Remus Teodorescu

Aalborg Universitet

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IEEE Transactions on Industry Applications

Optimisation of Multi-Energy System Operation with Convex Efficiency Representation at Partial Loading

The optimal operation of multi-energy systems (MES) that supply a demand formed by different energy vectors can be determined based on a given objective function with the relevant constraints. An efficient approach formulated in the literature defines an optimisation model with linear constraints considering constant efficiency or constant coefficient of performance ( COP ) of the individual equipment. This paper extends this optimisation model by considering non-linear convex expressions of the equipment efficiencies and COP s. The optimisation with linear constraints is solved in an iterative way, by updating the efficiencies and COP s at each iteration until the convergence criterion is satisfied. The results of this approach are shown for a MES that supplies electricity, heat and cooling demand in representative cases for winter and summer periods. The relevant aspects are the possibility of determining more …

Afshin Rezaei-Zare

Afshin Rezaei-Zare

York University

IEEE Transactions on Industry Applications

Response of MMC-HVDC Systems to Geomagnetic Disturbances

This paper presents a detailed investigation of the performance of MMC-based HVDC systems in the event of a solar Geomagnetic Disturbance (GMD). Detailed models of an MMC and submodules are used to acquire the accurate behavior of the MMC during GMDs. Under such conditions, the current harmonics arising from the DC shift in the transformer flux are distributed between the MMC and grid, distorting the current and voltage waveforms. In this study, a model for the distribution of the current harmonics is developed. It is revealed that the distribution of the second harmonic current is affected not only by the MMC impedance but also by the output current and voltage of the converter. The simulation results in the EMTP show that with the constant power factor control strategy, the MMC does not respond to the increase in reactive power consumption by the transformer. Consequently, a solution approach is …

Jung-Ik Ha

Jung-Ik Ha

Seoul National University

IEEE Transactions on Industry Applications

Single-Sided Compensation Network Design Method for Capacitive Power Transfer System Considering Coupling Variation

In capacitive power transfer systems, coupling variation inevitably occurs due to air gap variation and coupler misalignment. This paper presents a single-sided compensation network design method for capacitive power transfer systems considering coupling variation. The proposed method adopts a single-sided compensation network to reduce the volume and weight of the receiver side circuit. The proposed compensation network, within a preselected narrow operational frequency range, effectively transforms the variable load impedance into a single resistive point, resulting in constant output power and zero-phase angle operation under coupling variation. The proposed method employs the impedance matching network design based on a twoport network analysis. The validity of the proposed design method is confirmed with a simulation and a 1.2 kW small air gap capacitive power transfer system prototype …

Sukumar Kamalasadan

Sukumar Kamalasadan

University of North Carolina at Charlotte

IEEE Transactions on Industry Applications

Parametrically Optimized Synchronous Condenser Coordinated Control Framework to Enhance Bulk Grid Stability With Renewables

The power grid complexity has increased with the expanded penetration of renewable energy resources, creating grid performance challenges. This work proposes a parametrically optimized coordinated control framework and investigates the impact of a synchronous condenser and its associated parameters on the oscillation characteristics and stability of a weak grid system integrated with renewable energy (e.g., wind). For analysis, a model of a power grid with a wind farm (Type 4), and a thermal power station lumped group approach (e.g., exciter system and steam governor) are developed to model the grid with a variable impedance network. Then, to evaluate the specific impact of the synchronous condenser parameters (e.g., exciter gain, transient reactance, and inertial constant), a linearized state-space model is constructed. A design guideline is proposed, based on the study outcomes, for the optimal …