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Sinusoidal pulse width modulation (SPWM) is a method to generate the switching gate pulse of the converter. Overmodulation is a method where the modulation index exceeds the unity value and the system goes into the nonlinear region. To maintain the system in a linear region when operating in the overmodulation region, some techniques are developed. These techniques helped to operate the system in the linear range. Medium and high-power energy conversion systems mostly use a modular multilevel cascaded converter (MMCC), which has been an issue improving significantly in recent years. In this article, MMCC-based overmodulation techniques are compared with conventional PWM and analyzed on DC bus utilization (DBU), and total harmonic distortion (THD). MATLAB/Simulink digital platform used demonstrate overmodulation technique.

Background: Remote area electrification is a social responsibility that needs to be catered by research fraternity. One of the most viable technology as a solution, is the renewable energy source (RES) based power generation. However, RES is intermittent and thus, mostly ineffective without an energy storage device. Energy storage device comes at increased cost and may not be a cost-effective solution to the problem. Introduction: One solution that has been frequently proposed to reduce the intermittency of RES is hybridization. Hybridization of RES such as wind energy conversion system (WECS) with solar energy conversion system (SECS) is the most basic solution offered owing to their complementary nature. Therefore, this paper sees SECS in the role of supporting WECS in regions with highly intermittent wind conditions. In this paper, a novel technique of hybridization of WECS with SECS has been proposed. Method: The basic idea of the paper is to control the dc-link voltage from the generation side by regulating the power generated by RES as per load demand using minimum components. The underline principle is the relative lower time constant of solar panel and battery system in comparison to a wind turbine. Result: The experimental results on the proposed system shows that the SECS supports the WECS at higher wind turbulence and low wind conditions. Conclusion: This unique feature of the proposed system enables a WECS supported by a small rated SECS to attain high power reliability and thus, suitable for application such as remote area electrification.

Nowadays power crises in different countries are observed and the main cause of the power crisis is the huge gap between the supply and demand of electricity, renewable energy sources are identified as an alternative to overcome the power crisis gap. Renewable wind energy is the most promising energy source. Increasing the integration of wind energy into the grid causes the exploitation of power quality. Hence there is a need to deal with this issue. In this case, supercapacitors and custom power devices are introduced as smart energy storage devices in grid-connected wind energy systems for power quality enhancement features. The indirect current control scheme has interfered with custom power devices based on DSTATCOM. The optimal MATLAB-based smart energy storage model and hardware results are compared and validated. power quality improvement feature of grid-connected wind energy system using DSTATCOM is highlighted. The main aim of this study is to determine and interface the optimistic energy storage device into grid connected wind energy system. So that the stability of the wind energy system is to be maintained and also able to enhance the overall efficiency of the wind energy system.

This paper described a novel pulse width modulation (PWM) technique in reduced switch count multilevel inverter (MLI) for renewable power applications. Therefore, the proposed technique finds a better solution in the multilevel inverters used for improving power quality, efficiency and reduction of switching and conduction losses. It produces a smoother sinusoidal output waveform with reduced total harmonic distortion (THD) using different modulation technique. The novel PWM technique consists of nearest level control (NLC) and level shift pulse width modulation (LSPWM). Normally semiconducting devices are added for increasing number of levels. It affects the power quality and efficiency due to losses. In this work, MLI topology with reduced number of switches count for NLC and LSPWM is presented. The single-phase and three-phase inverter configuration is used in proposed mythology. Detailed simulation results for 7-level inverter of single and three-phase inverters are presented in this paper. It is observed that NLC method is better efficiency and reduced THD than LSPWM for better utilization in renewable power applications.