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Multilevel inverters have the capability to produce an AC staircase output waveform without using a bulky passive filter. Therefore, the multilevel inverters are gaining more and more popularity, among the different types of inverters, for photovoltaic applications in the modern era of technology. However, if the switching angle arrangement technique is not selected appropriately then the total harmonic distortion of the voltage output waveform may become undesirable. In this paper, Half-Equal-Phase, Feed-Forward and Selective Harmonics Elimination Pulse Width Modulation switching angle arrangement techniques at different power factors (i.e., 1.0, 0.75 and 0.50) are applied to a cascaded battery-boost inverter. PSIM software is used to evaluate and compare the performance of a 9-level cascaded battery-boost inverter with three switching angle arrangement techniques at power factors of 1.0, 0.75, and 0.50, respectively. Simulation results show that the Selective Harmonics Elimination Pulse Width Modulation technique can produce an output voltage and current waveform with the lowest total harmonic distortion. On the other hand, the output current waveform produced by power factor 0.50 had the lowest total harmonic distortion.

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High temperature stability of band-gap energy of active layer material of a semiconductor device is one of the major challenges in the field of semiconductor optoelectronic device design. It is essential to ensure the stability in different band-gap energy dependent characteristics of the semiconductor material used to fabricate these devices either directly or indirectly. Different models have been widely used to analyze the band-gap energy dependent characteristics at different temperatures. The most commonly used methods to analyze the temperature dependence of band-gap energy of semiconductor materials are: Passler model, Bose–Einstein model and Varshni’s model. This paper is going to report the limitation of the Bose–Einstein model through a comparative analysis between Bose–Einstein model and Varshni’s model. The numerical analysis is carried out considering GaN as it is one of the most widely used semiconductor materials all over the world. From the numerical results it is ascertained that below the temperature of 95o K both the models show almost same characteristics. However beyond 95o K Varshni’s model shows weaker temperature dependence than that of Bose–Einstein model. Varshni’s model shows that the band-gap energy of GaN at 300o K is found to be 3.43eV, which establishes a good agreement with the theoretically calculated band-gap energy of GaN for operating at room temperature.