Equivalent circuit model of a battery [16]

Equivalent circuit model of a battery [16]

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Rechargeable batteries are critical components in many electrical systems nowadays. One has to ensure reliable diagnosis and assessment of the installed batteries for smooth and safe operations. Assessment of the remaining capacity of a battery is crucial diagnostic information. A battery management system (BMS) needs to reliably report the ability...

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... Contingency management for battery systems starts with prognostics and health management (PHM), and several researchers have studied precise estimation of battery remaining useful life (RUL) computed from battery SoC. Such methods have used extended Kalman filter (EKF) [19], unscented Kalman filter (UKF) [20], unscented transform [21], particle filter [22], neural network [23], and Gaussian process regression (GPR) [24,25] formulations. Sharma and Atkins [26] proposed a multibattery reconfiguration for UASs using a prognostics-informed MDP. ...
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... The safe region contains all the desired aspects; however, the failure region represents the undesired manners. Therefore, several battery harmful outcomes are avoided by detecting the transition from safe region to failure region [4], [5], [6], [7]. The battery capacity represented by the state of charge (SOC) plays a vital role in battery protection strategies represented by battery management systems (BMSs). ...
... However, the OCV method is suitable for low-current applications and the constructed lookup table and mathematical equation parameters should be updated to compensate for the battery aging effect. In contrast to simple methods, classification and machine learning approaches were employed to create early battery failure detection methods without utilizing the SOC in the real-time tests; however, the SOC was required in the labeling phase [7], [6]. Machine learning techniques require a considerable amount of training data, and this option is not always available. ...
... It is possible to generate model elements based on actual process. In [6], [7], supervised classification approaches were proposed, in which all observations with SOC in the range of 100%-10% were labeled in the safe region; however, the remaining observations with SOC in the range of 10%-0% were assigned to the failure region. To determine the required classes before starting the actual tests, the discussed labeling strategy based on the SOC criteria was employed in this study. ...
... Contingency management for battery systems starts with prognostics and health management (PHM), and several researchers have studied precise estimation of battery remaining useful life (RUL) computed from battery state of charge (SoC). Such methods have used Extended Kalman Filter (EKF) [10], Unscented Kalman Filter (UKF) [11], unscented transform [12], particle filter [13], neural network [14], and Gaussian Process Regression (GPR) [15,16] formulations. Sharma et al. [17] proposed multi-battery reconfiguration for UAS using a prognostics-informed Markov Decision Process (MDP). ...
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... Consequently, the estimated SOC has been utilized by battery management systems (BMSs) to ensure adequate performance of the battery unit [6]. Therefore, a battery model plays a vital role in BMS structure to protect the battery unit from abuse factors, such as an over-discharge scenario [7,8,9,10]. Moreover, battery models are important tools in charging and battery lifetime-extension algorithms [11,12]. ...
... As a result, the mean values of the individual parameter arrays were determined to obtain the required constant parameter values that were utilized by the model elements in Eqs. (6)- (9). ...
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In this study, the theoretical framework of optimal control was employed to construct an optimal parameter estimation (OPE) methodology that estimates the parameters of an equivalent-circuit battery model backward in time. In contrast, a forward adaptive parameter estimation (APE) method was utilized in the present study for comparison purposes. APE inspired this study to develop the proposed approach, because APE has been examined in previous studies and reported as a fast parameter estimation technique. Both techniques were tested and verified using simulation and experimental results, which showed that OPE exhibited a better performance than APE in terms of computational time and accuracy. Moreover, the proposed strategy was less affected by an increase in the number of samples of identification data. Therefore, the OPE approach is a reliable choice for recomputing the model parameters from time to time, especially when the battery model parameters vary with time owing to temperature and aging effects.
... In this context, machine learning algorithms may play a promising role. Different supervised [54][55][56][57], unsupervised [58], and reinforcement learning [59] strategies have already been addressed in the fields of individual battery system components. Yu [60] and Li et al. [61] propose prognostic state-of-health frameworks using Gaussian Process Regression (GPR). ...
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... The battery model was utilized without linearization in the UKF and PF algorithms. Battery models have a key function in battery management systems (BMSs) to ensure safe and reliable performance, as reported in [11] and [12]. Unlike BMSs, a battery model is also required in algorithms for charging control [13]. ...
... According to [37], the ML function behaves as a Nussbaum VOLUME 8, 2020 function if a ∈ (2, 3] and b = 1. Hence, the ML function is represented by Eq. (12), where (z + 1) = z (z), z > 0 is the standard gamma function. In [38], the Mittag-Leffler function was constructed in the MATLAB/Simulink environment. ...
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In this study, image feature extraction techniques based on principal component analysis (PCA) and QR factorization were employed to represent the measured terminal voltage of several batteries in terms of a few dominant features instead of raw data. In previous studies, directly measured terminal voltage was used to create the feature space by inputting raw sampled data to a supervised classifier. This was ineffective because it leads to false alarms owing to data overlap and requires a relatively considerable processing time. However, the proposed methods are useful for building a reduced and distinguishable feature space, where a classifier can quickly process and separate regions with small labeling errors. Therefore, different supervised machine learning classifiers, namely neural networks (NNs), k-nearest neighbors (kNNs), and support vector machines (SVMs), were trained based on the dominant features to distinguish between the safe and failure regions of battery units. Interestingly, the proposed technique requires no knowledge of the model parameters and state of charge (SOC) in the training and testing phases, although the SOC is necessary in the data labeling stage. The results showed that the nonlinear classifiers represented by NNs and kNNs demonstrated slightly better detection performance than the linear SVMs.
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Battery operated devices are common in everyday life. Deciding when a warning for impending battery voltage collapse should be triggered is not trivial. This paper develops an impending battery terminal voltage collapse detection system using a universal adaptive stabilizer (UAS) and a well-known trend filter. This eliminates requiring knowledge of battery model parameter values, or initial state-of-charge (SOC). The proposed approach overcomes the need for extensive training when compared to using neural-networks based techniques. Also, the developed trend filter when used with a UAS, eliminates the need for selecting windows of data to be processed. This is advantageous compared to earlier work, which uses a different trend filtering mechanism, because selection of window sizes is not straightforward. Further, the approach used in this work shows that the UAS based technique is implementable on a cell phone. Associated mathematical results, and experimental data from such an implementation are presented. Additionally, the technique is also applied to other larger capacity Li-ion batteries showing its versatility. The developed technique can also be used to detect when the state-of-health (SOH) of a Li-ion battery is about to enter an unsafe region.