No abstract

PV generating sources are one of the most promising power generation systems in today’s power scenario. The inherent potential barrier that PV possesses with respect to irradiation and temperature is its nonlinear power output characteristics. An intelligent power tracking scheme, e.g., maximum power point tracking (MPPT), is mandatorily employed to increase the power delivery of a PV system. The MPPT schemes experiences severe setbacks when the PV is even shaded partially as PV exhibits multiple power peaks. Therefore, the search mechanism gets deceived and gets stuck with the local maxima. Hence, a rational search mechanism should be developed, which will find the global maxima for a partially shaded PV. The conventional techniques like fractional open circuit voltage (FOCV), hill climbing (HC) method, perturb and observe (P&O), etc., even in their modified versions, are not competent enough to track the global MPP (GMPP). Nature-inspired and bio-inspired MPPT techniques have been proposed by the researchers to optimize the power output of a PV system during partially shaded conditions (PSCs). This paper reviews, compares, and analyzes them. This article renders firsthand information to those in the field of research, who seek interest in the performance enhancement of PV system during inhomogeneous irradiation. Each algorithm has its own advantages and disadvantages in terms of convergence speed, coding complexity, hardware compatibility, stability, etc. Overall, the authors have presented the logic of each global search MPPT algorithms and its comparisons, and also have reviewed the performance enhancement of these techniques when these algorithms are hybridized.

Maximum Power Point Trackers (MPPTs) are power electronic conditioners used in photovoltaic (PV) system to ensure that PV structures feed maximum power for the given ambient temperature and sun's irradiation. When the PV panels are shaded by a fraction due to any environment hindrances then, conventional MPPT trackers may fail in tracking the appropriate peak power as there will be multi power peaks. In this work, a shuffled frog leap algorithm (SFLA) is proposed and it successfully identifies the global maximum power point among other local maxima. The SFLA MPPT is compared with a wellentrenched conventional perturb and observe (P&O) MPPT algorithm and a global search particle swarm optimisation (PSO) MPPT. The simulation results reveal that the proposed algorithm is highly advantageous than P&O, as it tracks nearly 30% more power for a given shading pattern. The credible nature of the proposed SFLA is ensured when it outplays PSO MPPT in convergence. The whole system is realised in MATLAB/Simulink environment.

No abstract

This paper proposes modeling and simulation of photovoltaic model. Taking in to account the temperature and sun"s irradiance, the PV array is modeled and its voltage current characteristics and the power and voltage characteristics are simulated. This enables the dynamics of PV system to be easily simulated and optimized. It is noticed that the output characteristics of a PV array are influenced by the environmental factors and the conversion efficiency is low. Therefore a maximum power tracking (MPPT) technique is needed to track the peak power to maximize the produced energy. The maximum power point in the power-voltage graph is identified by an algorithm called perturbation & observation (P&O) method or Hill climbing. This algorithm will identify the suitable duty ratio in which the DC/DC converter should be operated to maximize the power output. The results confirm that the photo voltaic array with proposed MPPT controller can operate in the maximum power point for the whole range of assumed solar data (irradiance and temperature).

Induction heating (IH) applications aided by power electronic control system have become very attractive in the recent past. The power electronics circuits succumb to severe switching loss, lower power density if proper switching methodology is not adhered. A state of uncertainty is indispensable in IH application as the power required by the load varies depending upon the nature of work piece. This uncertain issue makes the selection of the control algorithm and controller very vital. The mundane controllers may not be compatible to combat the uncertainties and leads to exhibit dynamic problems say transients, peak overshoot and poor response. Henceforth, the IH system requires a superlative converter topology and control scheme in order to have reduced switching loss and to improve the system performance there by negating the uncertainties. Here, in this work, a direct AC–AC boost resonant converter fed by pulse density modulation (PDM) is realized in a single stage mode. A fuzzy logic-based PDM control technique improves the efficiency and provides the versatile power control with reduced time domain specifications for dynamic changes in load. The proposed system has been studied using MATLAB/SIMULINK and validated using a hardware prototype employing dsPIC30F4011 microcontroller. The results reveal that efficient control over power can be accomplished by varying the density of the switching pulses, and thereby the efficiency is enhanced even with reduced component count. Also, the single-stage conversion is effective than its two-stage counterpart.

The concept of induction heating is slowly entrenching as it has the traits of homogeneous heating, zero pollution and higher power density. To achieve these traits convincingly in reality, there is a need to develop energy efficient converter topologies, which aid in achieving power regulation of soft switching and very high frequency operation. This paper presents the salient features of converter topologies used for domestic and industrial heating applications with a focus on its stage-wise power conversion, power density, load handling capacity, soft switching, reliability and size. The performance of these topologies is analysed in terms of converter switching frequency, power rating, modulation techniques, flicker, user performance and efficiency. Moreover, this review paper predicts the future trends associated with the adaptation of wide band-gap power semiconductor materials, multi-output topologies, variable frequency control scheme with minimum losses and filter design to improve source-side power factor. The detailed technology review will be extremely useful for researchers, designers and engineers in choosing the appropriate topology for the chosen application.

No abstract