Future ageing trajectory prediction for lithium-ion battery considering the knee point effect

IEEE Transactions on Energy Conversion

Published On 2021/11/25

Lithium-ion batteries have been widely applied in energy conversion sectors, where effective future ageing prediction is crucial to guarantee their safety and performance. Due to the highly nonlinear ageing behaviours, developing a reliable method that could not only consider the knee point effect but also predict the future ageing trajectory with uncertainty quantification poses a formidable task. This paper derives a machine learning solution, based on the migrated Gaussian process regression (GPR), for predicting future battery two-stage ageing trajectory. Specifically, a base model is first offline identified from the easier collected accelerated-speed ageing data, through which the long life ageing information can be effectively learned. With this base model, a migrated mean function is then designed and coupled within the GPR framework for battery ageing predictions. Experimental data from three different …

Journal

IEEE Transactions on Energy Conversion

Published On

2021/11/25

Volume

37

Issue

2

Page

1282-1291

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

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Remus Teodorescu

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Remus Teodorescu

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Remus Teodorescu

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IEEE Transactions on Energy Conversion

Dual MRAS for Robust Rotor Time Constant Compensation in IFOC IM Drives

The induction motor drive with indirect field-oriented control (IFOC) is widely adopted due to its simple structure and easy implementation. The rotor time constant plays the most crucial role in IFOC. However, the rotor resistance varies with temperatures, and the rotor inductance changes with the current magnitude in practice. Furthermore, an accurate estimation of such parameters is challenging. The parameter mismatch between the actual and the estimated rotor time constant deteriorates the performance of the IFOC vector control due to an error in the estimated rotor flux position. This paper presents the theoretical analysis of the effects of the inductance errors in the conventional Q-MRAS method, which is widely used to compensate for the rotor time constant. Next, this paper proposes the dual MRAS consisting of a novel stator flux-based MRAS and the conventional Q-MRAS. The proposed dual MRAS method …

Lijian Wu

Lijian Wu

Zhejiang University

IEEE Transactions on Energy Conversion

A Computationally-Efficient Analytical Model for SPM Machines Considering PM Shaping and Property Distribution

Nowadays, various analytical models (AMs) have been developed to analyze SPM machines with magnet shaping technique consideration, but their mechanism are all based on division and superposition theory, and numerous repetitive model calculations are required, which greatly attenuates the inherent speed superiority of AMs. In this article, a new fast AM is proposed, which can analytically solve the magnetic field generated from an arbitrary number of currents to obtain the magnetic field solution for shaping PM without any repetitive model calculation. Besides, five existing typical AMs considering shaping PMs are implemented and compared with the new model, viz., radial and tangential PM segmented method, traditional equivalent current method, and conformal mapping models. The comparison study investigates the adjustable model parameters, the dimension of the stiffness matrix, the number of …

Xu Cai

Xu Cai

Shanghai Jiao Tong University

IEEE Transactions on Energy Conversion

Control of Virtual Synchronous Generator with Improved Transient Angle Stability Under Symmetric and Asymmetric Short Circuit Fault

Implementation aspects of fault-ride-through (FRT) operation in voltage source converter with virtual synchronous generator (VSG) control are discussed in this paper. The phenomenon of voltage decline during fault periods is recognized to be intricately associated with the interplay between power angle movement and the trajectory of current saturation resulting from the application of current limiters. It is explained how the output reactive power is restricted once the current reaches its limit, thus rendering the manipulation of reactive power not unconditionally achievable. It is also revealed that preferably voltage support and robust transient angle stability can be attained by minimizing power angle movement and allowing reactive power to be naturally generated instead of explicitly specifying reactive power commands from the controller. Motivated by these findings, a novel FRT strategy is proposed to attain the …

Maarten de Boer

Maarten de Boer

Carnegie Mellon University

IEEE Transactions on Energy Conversion

Evaluation of Rotational Speed Limits in an Axial Flux-Switching Motor Constructed from Metal Amorphous Nanocomposite Magnetic Cores

Given the promising high frequency magnetic properties of metal amorphous nanocomposite (MANC) soft magnetic materials (SMMs), recent efforts seek to use MANCs in electric motors to achieve high specific power utilizing elevated magnetic frequency. Such motors can operate at high rotational speed, as eddy current losses pose less limitations on their performance. It is thus important to understand mechanical stress distributions in a motor constructed from MANCs and to predict the likelihood of failure for such a machine at high speeds. Here, we model the residual stress due to the manufacturing process and the operating rotational stress of a MANC rotor. Previously reported failure distributions of laminated MANC ribbons are then used in conjunction with stress results to predict MANC motor failure rates. Because of brittle MANC failure, a design philosophy based on statistics rather than factor of safety …

Yao Sun

Yao Sun

Central South University

IEEE Transactions on Energy Conversion

Implementation and Stability Analysis of An Improved V/f Induction Motor Control Scheme based on Constant Rotor Flux

An improved volts per hertz ( V/f ) control scheme based on constant rotor flux for induction motors is proposed in this paper to improve the low-speed performance and solve the problem of speed droop when loaded. A voltage drop compensation method is adopted to ensure correct excitation and a slip compensation method is proposed to decrease speed error. Different from adopting ideal excitation voltage in most previous research, the actual excitation voltage calculated from induction motor model is applied. Meanwhile, an oscillation suppression method is incorporated to mitigate current oscillation and ensure stability. And system's stability is proved with the small signal model analysis method. Finally, the effectiveness and correctness of the proposed scheme is verified by the experimental results on 5.5kW induction motor experimental platform.

Ratik Mittal

Ratik Mittal

University of South Florida

IEEE Transactions on Energy Conversion

Stability Enhancement for IBRs Operating in Weak Grids Through Proper Coordination and Control

In this work, a coordination and control scheme for multiple inverter-based resources (IBRs) operating in weak grids is proposed to improve stability margin close to the steady-state power transfer limit. The scheme can achieve further stability enhancement even with well-designed individual IBR's control. The key philosophy is to have one set of IBRs providing modulated reactive current that can mitigate weak grid oscillations. This philosophy is realized through coordination or implementing a voltage feedback control to modulate the reactive current order of a set of IBRs. To test its robustness, three testbeds experiencing 3-Hz to 7-Hz oscillations are examined. Additionally, a grid-forming converter is also tested. In electromagnetic transient (EMT) computer simulation, the proposed coordination scheme is shown to improve both small-signal stability margin and large-signal stability. Furthermore, experiments have …