Satish M. Mahajan

Grid-following inverter (GFLI) systems equipped with LLCL filters offer superior harmonics attenuation but suffer from significant resonance issues and stability challenges under varying grid conditions. Traditional damping strategies, such as proportional-resonant (PR) controllers with active or passive damping, partially address these issues but often introduce added system complexity, increased losses, or degraded performance due to digital control delays. Moreover, these approaches typically lack guarantees of global asymptotic stability during transient disturbances. To overcome these limitations, this paper proposes a novel control strategy based on Lyapunov function-based current (LFBC) control for LLCL-filtered GFLI systems. The proposed approach ensures global asymptotic stability, robust dynamic performance, and effective resonance suppression without relying on passive loss components. The control framework integrates an active damping mechanism and a PR controller for reference signal generation, enhancing adaptability and eliminating the need for differentiation or explicit knowledge of filter parameters. Theoretical analysis using root-locus and Bode plots validates the controller's stability, and comprehensive design guidelines are provided. The experimental findings confirm that the presented LFBC controller markedly improved stability, fast dynamic response, and grid current response while minimizing total harmonic distortion.

Electric vehicle (EV) loads impact on the electric power utility distribution network (DN) can be best investigated when studying the corresponding EV charging stations (EVCS) in the DN. However, different types of data/metadata need to become available for properly modeling EVCSs for relevant power system studies. One metadata is EV users’ behavior or charging pattern. Generative AI synthetic data can be utilized to replicate EV user behavior as an alternative to metered EV data. In this paper, we first present the EVCS electrical data requirements for cyber-physical modeling and its impact on two main categories of power distribution system studies, i.e., operational planning and electromagnetic transient studies. Distribution planners can benefit by ensuring these data requirements are met prior to delving into relevant studies. We then describe the methods for generating synthetic EV data, along with sample results. Synthetic EV charging data have the potential to be utilized as input EVCS load-shapes to inform distribution grid techno-economic and offline/real-time cyber-physical simulations.

Inductive Wireless Power Transfer (WPT) technologies are advancing significantly in the electric vehicle (EV) charging applications. Misalignment between transmitting and receiving coils can considerably affect power transmission efficiency in WPT systems. Prior research involved power electronics as well as electromagnetic couplers. This work focuses on the coil design aspect of electromagnetic couplers. A relatively new concept of Symmetrical Cross Double-D (SCDD) type of the coil design is introduced specifically to maximize tolerance to misalignment while sustaining significant amount of power transferred. Mutual inductance was determined for the perfect alignment and misalignment positions of the SCDD coils. Mutual inductance obtained from the simulation was validated from the experimental measurements. The SCDD electromagnetic coupler demonstrated almost 2.5 times superior tolerance to misalignment of coils compared to the conventional circular coupler while maintaining at least 78% of maximum power transfer even at a lateral misalignment of 40 mm.

The integration of battery energy storage systems (BESSs) within active distribution networks (ADNs) entails optimized day-ahead charge/discharge scheduling to achieve effective peak shaving.The primary objective is to reduce peak demand and mitigate power deviations caused by intermittent photovoltaic (PV) output. Quasi-static time-series (QSTS) co-simulations for determining optimal heuristic solutions at each time interval are computationally intensive, particularly for large-scale systems. To address this, a two-stage intelligent BESS scheduling approach implemented in a MATLAB–OpenDSS environment with parallel processing is proposed in this paper. In the first stage, a rule-based decision tree generates initial charge/discharge setpoints for community BESS units. These setpoints are refined in the second stage using an optimization algorithm aimed at minimizing community net load power deviations and reducing peak demand. By assigning each ADN community to a dedicated CPU core, the proposed approach utilizes parallel processing to significantly reduce the execution time. Performance evaluations on an IEEE 8500-node test feeder demonstrate that the approach enhances peak shaving while reducing QSTS co-simulation execution time, utility peak demand, distribution network losses, and point of interconnection (POI) nodal voltage deviations. In addition, the use of smart inverter functions improves BESS operations by mitigating voltage violations and active power curtailment, thereby increasing the amount of energy shaved during peak demand periods.

In this article, the effect of the dead-time on a single-phase wireless power transfer (WPT) system is studied in detail. In practice, the dead-time is always placed between the complementary switching pulses of the inverter phase-leg. At higher operating frequencies, the dead-time issues in the resonant inverter become critical, especially as the power level increases. The detailed analysis of the dead-time on a WPT system is discussed for different operating conditions of the inverter duty-cycle and power factor. The switching characteristics of the WPT system inverter are analyzed, and the notch phenomenon that appears at the output of the inverter is also discussed. A notch equation based on the observations is derived to predict the notch occurrence during the system operation. Furthermore, the mathematical expressions are presented for different notch conditions. Subsequently, the effect of the notches on the sensitivity and the power transfer of the series–series compensated WPT system is analyzed. Finally, the approach is verified experimentally on an 8-kW WPT system prototype, and the results are compared with the theoretical analysis.

This paper presents a methodology to evaluate transient stability constrained available transfer capability (ATC). A linear and fast line flow–based (LFB) method was adopted to optimize the ATC values. This enabled the direct determination of the system source–sink locations. This paper formulated different market transactions considering bilateral and multilateral impacts in the stability constrained ATC. The proposed method was demonstrated on the WECC 9-bus and IEEE 39-bus systems. The critical energy performance index (CEPI) enabled the direct identification of candidates for contingency screening based on ranking. This index helped to reduce the list of credible contingencies for ATC evaluation and, therefore, the computation time. The results of the proposed ATC method are consistent with the literature and can be deployed for fast assessment of the impact of transactions in an electric power system.