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In this paper, a real-time implementation of selective harmonic elimination pulsewidth modulation (SHEPWM) using generalized Hopfield neural network (GHNN) as applied to the single-phase inverter is designed and discussed. Finding the location of the switching instants in the case of SHEPWM involves the solution of a set of nonlinear algebraic transcendental equations. The problem is redrafted as an optimization problem, and it is solved by using GHNN. Though, in principle, the $n$ number of harmonics can be eliminated using the presented methodology, this paper tries for the case of the elimination of the 5th-, 7th-, 11th-, and 13th-order harmonics while retaining the desired fundamental. An energy function is formulated for this problem and the set of ordinary differential equations (ODEs) describing the behavior of GHNN is obtained. A program in KEIL C was developed to solve these systems of ODEs by the Runge–Kutta fourth-order method to give the switching instants for continuously varying modulation indexes $(M)$. A MATLAB simulation was carried out, and an experimental setup was also constructed in order to validate the simulated results. The fast Fourier transform analysis of the simulated output voltage waveform and the experimental output voltage waveform confirms the effectiveness of the proposed method. Hence, the proposed method proves that it is much applicable in the industrial applications by virtue of its suitability in real-time applications. [ABSTRACT FROM PUBLISHER]

A visible light communication (VLC) system that utilizes a single phosphorescent white light emitting diode (LED) under a 3 m line of sight (LOS) indoor free space transmission length has been established in this work. Proposed lattice pre-equalization circuit in it is opted to overwhelm the bandwidth constraint of LED. This VLC system allows non-return to zero on-off keying (NRZ-OOK) data transmission up to 1.3 Gbps with the bit error rate (BER) of 18.241e-009, which is under a pre-forward error correction limit of 3.8*10-03 by employing an optimized pre-equalizer. The concise assess on the characteristic features of an equalizer are also done. In addition, the intention of all the components in this scheme and its results are conferred. This VLC system clearly demonstrates the capability of constant resistance recurrent equalizer structure for this LED device. The upshots show that this scheme has immense prospective for a low cost and better indoor wireless broadband access VLC applications. To date, to the best of the authors' knowledge, this is an uppermost data rate reached by exploiting an optimized single stage lattice pre-equalization circuit for OOK modulated phosphorescent white LED based VLC system. [ABSTRACT FROM AUTHOR]