Grid-forming inverters (GFMIs) are crucial for grids experiencing higher penetration of photovoltaics. Uncertainties in the utility grid make the GFMI system unstable. Thus, using a virtual synchronous generator (VSG) enhances system stability and grid stiffness by reducing the rate of change of frequency (RoCoF). Thus to deal with harmonics and oscillations caused by various uncertainties in the system, this article proposes an elevated adaptive integrated control strategy (EAICS) for a three-phase grid-tied VSG (TPGTVSG) system, which integrates a modified proportional resonant current (MPRC) controller and a phase-corrected reference current (PCRC) generator to further improve overall system performance. The MPRC controller also includes an adaptive power control for the VSG, which helps to reduce the injected grid current harmonics and dampens the power and frequency oscillations under distorted/unbalanced grid voltage conditions. Whereas, the PCRC serves the purpose of synchronization without a dedicated synchronization unit, thereby making the TPGTVSG self-synchronizing and thus reducing the computational burden and complexity. Furthermore, the grid frequency adaptability of the TPGTVSG system is enhanced by suitably modifying the control coefficients used in the VSG power control loop, thereby stabilizing the power oscillations. Additionally, the article also presents a small signal modeling analysis of VSG to examine how parameter perturbations affect power and system frequency. Finally, the suggested EAICS controller response to the system is examined experimentally using a laboratory prototype.

This article presents an off-board bidirectional battery charger for electric vehicles (EV s) that has been designed to perform various tasks beyond simply charging electric vehicles (EVs) like Grid-to-Vehicle (G2V), Vehicle-to-Grid (V2G) and Vehicle-to-Home (V2H) technologies and also improving the grid power quality (PQ). During charging mode, the G2V mode of operation takes place. Here, power flows from the utility grid to the vehicle with sinusoidal current and also maintains a unity power factor. Similarly, in discharging mode, the V2G mode of operation takes place. In this case, the power is delivered from the batteries of the EV to the utility grid. During the V2H mode of operation for the period of grid disruptions, EV s provide an uninterrupted power supply to domestic loads. The adopted topology and control technique is implemented to operate the laboratory-developed prototype electric vehicle charger (EVC) to verify the simulation results at various operating conditions.

This research paper discusses a bidirectional DC-DC fast charger (or level-3 charging system) to obtain a high-power level. However, two types of EV charging systems are available, i.e., an on-board charging system and an off-board charging system. For dc fast charging, it is essential to use the off-board charger to reduce the volume and weight of EVs significantly. This charger charges the EV battery using a Dual Active Bridge (DAB) topology for the DC-DC converter, which is better for bidirectional power flow, power density, and efficiency and has less passive component count than resonant circuits using inductors and capacitors. Furthermore, zero-voltage switching (ZVS) from light to medium load is challenging using Single-Phase Shift (SPS) control. This improves system reliability and efficiency by decreasing switch-bridge crosstalk caused by hard switching-ON. Optimizing phase shift reduces switch voltage stress. Double Phase Shift (DPS) and Triple Phase Shift (TPS) control may work but have disadvantages, like larger switching-OFF currents. Moreover, SPS is discussed with CCCV charging. The design for DAB includes two different voltage and current control loops using PI controllers to control the power flow between the two H-bridges of the DAB converter to charge the battery. All the results are presented, obtained from simulations done on MATLAB.

The grid-connected photovoltaic system (GCPVS) with distribution static compensator (DSTATCOM) capabilities plays a key role in providing an alternative way of power generation with enhanced power quality (PQ). For GCPVS, a three-phase, single-stage is considered in which local loads are connected at the point of common coupling (PCC). These loads create nonlinearities in the current, which are mitigated by GCPVS, thus enhancing the PQ. For the effective operation of GCPVS in satisfying the load requirement and feeding excess available PV power to the grid, a Weibull M-transform least mean square (WMLMS)- based control scheme is proposed in this article. This control scheme enables GCPVS to draw maximum power from the PV array, compensate for the load reactive power, load balancing, mitigate load current harmonics, and achieve sinusoidal grid currents at the unity power factor (UPF). However, during night time as PV power is absent, the system performs to operate as DSTATCOM. The GCPVS is developed using MATLAB/Simulink and simulated. The responses of GCPVS during various cases are found satisfactory, and THD of the grid currents are bound to IEEE-519-2022 standard.