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A grid connected photovoltaic (PV) based electric vehicle (EV) charging station is proposed that provides uninterrupted power supply to EV and non-linear domestic load. Here, PV is responsible for power transfer to the EV and household load. The proposed Normalized Gaussian Kernel Least Mean Square (NGKLMS) control technique mitigates several power quality (PQ) issues arising due to non-linear load, unbalanced load or change in solar irradiance (G). This technique lowers the harmonic content of the grid parameters based on IEEE 519 standard and maintains unity power factor (UPF). The superiority in performance of the proposed control is validated by comparing with conventional techniques like Least Mean Fourth (LMF) and Least Mean Square (LMS) in MATLAB/SIMULINK.

This paper investigates the application of a grid-connected off-board Electric vehicle (EV) battery charger on the reactive power compensation and simultaneously use as a battery charger (grid-to-vehicle (G2V)) and power generator (vehicle-to-grid (V2G)). The topology of the charger consists of a grid facing front-end AC-DC cascaded H-bridge bidirectional converter, which controls the power flow between the grid and EV battery using a back-end DC-DC bidirectional converter. The charger configuration provides galvanic isolation at the user end from the rest of the system as a safety measure. The proposed control algorithm follows the active power command for G2V and V2G operation along with reactive power command from the utility grid when requested, by controlling EV current and battery current. Furthermore, an adaptive notch filter based controller is designed for system phase estimation and generated reference current synchronization. The proposed control algorithm eliminates phase locked loop (PLL) from the controller design. As a result, the computational complexity of the controller reduces with improved steady-state and trainset performance. Furthermore, a 12.6 kVA off-board charger simulation model is developed in MATLAB/Simulink environment and the performance of the proposed control algorithm is tested during G2V, V2G, and reactive power compensation operation of the EV charger.

This paper presents a new super twisting sliding mode control for the isolated DC-DC bi-directional dual active bridge (DAB) power converter for enhanced output voltage regulation. The sliding mode control (SMC) is well known for its robustness and improved dynamics for non-linear systems. Still, it includes the drawback of high-frequency chattering and degradation of tracking performance. The suggested super twisting sliding mode control (ST-SMC) scheme incorporates the advantages of a sliding mode controller and eliminates the problem of chattering. Thus, improved dc-link voltage stability and high robustness for accurate reference voltage tracking are obtained. The output voltage in the DAB converter depends upon the power transferred through the transformer. The transferred power is a function of the phase shift of the voltage waveform of two H-bridges. The phase shift ratio is computed through the ST-SMC controller presented here utilizing the output voltage dynamic equation and power transfer equations for DAB converter. The proposed scheme which provides a robust control and an improved reference voltage tracking to the DAB converter performance. The proposed ST-SMC scheme is validated by simulation for 1 kW DAB converter in MATLAB-Simulink environment.

This paper presents a DC-DC bi-directional dual active bridge (DAB) power converter, and simulating direct power control (DPC) control for the power converter. The DPC control enables it to have an enhanced dynamic response with improved dc-link voltage stability while controlling the power flow. The output voltage is controlled by the amount of power flow while the power flow depends on the phase shift ratio between primary and secondary bridge. With the DPC control presented here, the control reference is calculated from output voltage and load current, and subsequently phase shift ratio is computed, thereby controlling the power flow. The fast control over the amount power flow provides an overall enhanced performance with improved reference voltage tracking as well as robustness against input voltage fluctuation and load variation. The proposed control scheme is simulated in Matlab Simulink environment.

This paper presents proportional integral direct torque control (PIDTC) and fuzzy direct torque control (FDTC) of induction motor (IM) using bus clamped space vector modulation (BCSVM), in which BCSVM always clamps any phase of the inverter for given switching period. Conventionally, the total cost of control scheme significantly increases in real time applications as it needs to sense three voltages, three currents, and speed of the IM. The proposed control scheme (PIDTC/FDTC) uses only single voltage and single current sensors are enough to estimate all voltages, currents, and speed of the IM using the phase locked loop control (PLLC) and the transport delay. The PLLC estimates frequency and amplitude of respective voltage/current waveform of the IM. The other two voltages/currents are estimated by providing proper delay using transport delay. In addition, the IM speed is estimated from the frequency command of PLLC. The PIDTC provides considerable distortion in current, flux, torque, and speed due to poor performance of PI-controllers. In order to improve the dynamic performance of IM drive the FDTC is used. In FDTC, the fuzzy controller estimates the control variable very close to practical values using Mamdani and Centroid methods. Also, the switching duty ratios of the inverter are independent of the switching period with FDTC.