The microgrid is a group of smaller renewable energy sources (REs), which act in a coordinated manner to provide the required amount of active power and additional services when required. This article proposes coordinated power management for a microgrid with the integration of solar PV plants with maximum power point tracking (MPPT) to enhance power generation and conversion using a hybrid MPPT method based on particle swarm optimization-adaptive neuro-fuzzy inference system (PSO-ANFIS) to acquire rapid and maximum PV power along with battery energy storage control to maintain the stable voltage and frequency (V-f) of an isolated microgrid. In addition, it is proposed to provide active and reactive power (P-Q) regulation for the grid connected. The approach used provides more regulation due to the least root mean square error (RMSE), which improves photovoltaic (PV) potential extraction. The comparison results of the PSO-ANFIS and P&O controllers of the MPPT and the controller of the energy storage devices combined with the V-f (or P-Q) controller of the inverter all show effective coordination between the control systems. This is the most important need for contemporary microgrids, considering the potential of changing irradiance in the grid following mode, the grid forming mode under an island scenario, and back-to-grid synchronization. With the test model, the islanded and grid-islanded-grid connected modes are investigated separately. The results demonstrate conclusively that the proposed strategies are effective. To run the simulations, MATLAB and SimPowerSystems are utilized.

A converter with high voltage gain is generally necessary for interfacing the photovoltaic (PV) systems with grid. However, more semiconductor components are needed to obtain a higher voltage gain, which results in increased losses. This article proposes a novel non-isolated cubic boost (NNICB) DC-DC converter for high-voltage PV applications with a wide voltage gain at a lower duty ratio. Compared to traditional high-gain DC-DC converter, the NNICB converter counters the drawbacks of increased component count and high voltage stress. The NNICB DC-DC converter has a continuous source current for PV applications with low-voltage stress across the diodes and switches. A detailed steady-state analysis of the NNICB topology is carried out for the ideal and non-ideal models, and their corresponding voltage gain equations are computed. Furthermore, the analysis is performed using MATLAB/Simulink and is validated using a 230 W laboratory prototype. The experimental results show that the efficiency of the proposed NNICB topology is 94.42% with a voltage gain of 10.5 at 45% duty ratio. This proves the superior performance of the proposed novel converter in comparison with the existing topologies.

In this paper, a new PWM gating scheme and a zero-voltage transition (ZVT) auxiliary circuit is proposed for a fixed frequency full-bridge CLL DC-DC resonant converter with a capacitive output filter. An approximate complex ac circuit approach is used for the steady state analysis of the converter. The optimum design of the converter is described with the help of design curves for a sample converter of 200 W power rating operating at a switching frequency of 100 kHz. The converter with applied gating scheme and ZVT auxiliary circuit provides zero-voltage switching (ZVS) to all the switches for the entire variations in loading and input voltage conditions ensuring higher conversion efficiency. PSIM simulations are carried out to verify theoretical predictions about the performance of the converter for various operating conditions. Finally, experimental results are provided to verify the feasibility of the proposed converter. The theoretical, simulation and experimental results are given and discussed.

In this paper, grid interactive photovoltaic (PV) system is designed for an electric vehicle (EV) charging application and stability of the system is analyzed. The small signal model for the system is derived by averaging and linearizing the state space equations and the condition for stable operation of PV integrated charger system is identified from the transfer functions. The proposed charger system implements a coordinated control between the converters to maintain a power balance between the sources and load. System stability is examined using root-locus plots and in addition, the controller is designed to improve the overall stability and reliability of the system. The proposed method provides a general framework for modelling EV charging systems which also details the importance of deriving the model with multiple energy sources. Further, proposed topology has bi-directional capability, which transfers excess PV power to the grid during off-charging hours. The efficacy of the proposed method is verified using the MATLAB Simulink environment for the different scenarios i.e., variation in the irradiation and disturbances in the grid voltage. The experimental study is conducted on a 1.5 kW laboratory prototype using a low-cost digital signal processing (DSP) controller (launchpad TMS320F28027F) and the measured results authenticate the simulation findings.

A novel space vector-based approach is introduced in this paper to selectively eliminate the lower order harmonics from the DC-AC converter output waveform by making use of double switching clamping sequences. This technique uses a volt-second balance for control of fundamental voltage while using the dwell time rearrangement of the active vector in a sub-cycle to obtain the elimination of fifth or seventh harmonics. Further, the closed-form expression of the dwell time-division coefficient (DTDC) for the active vector dwell time division rearrangement is expressed. The proposed PWM technique is compared with other space vector-based PWM techniques in terms of voltage weighted total harmonic distortion, switching power loss, and lower order harmonic magnitudes. Further, the experimental results are presented to show the effectiveness of the proposed PWM techniques in terms of harmonic elimination.

This paper discusses the operation and performance comparison of LCL-T DC-DC resonant power converter when controlled with fixed-frequency phase-shifted gating (PSG) and modified-gating signals (MGS) schemes. The converter is designed to operate in lagging power factor mode to accomplish zero-voltage switching (ZVS) of the inverter switches. The operating principle of the converter with the two proposed gating schemes is explained. A brief steady-state analysis of the converter using Fourier series approach is presented. The choice between PSG and MGS schemes is made by comparing the performance of the converter. It is found that both the gating schemes are effective in regulating the output voltage for variable input voltage and loading conditions. However, the efficiency of the converter is found to be higher with MGS due to the fact that only one switch loses ZVS as compared to two with the PSG when operated with maximum input voltage. Also, the variation in pulse-width angle (ä) required to regulate the output voltage is small in MGS as compared to that with PSG. A 300 W experimental prototype of the converter has been built and tested to verify the theoretical results. It is experimentally confirmed that the MGS control gives the better performance than the PSG control for different input voltage and loading conditions.