Ezzidin Hassan Elmabrouk Aboadla

Selective Harmonics Elimination technique in single phase unipolar H-bridge inverter

Specific odd harmonics can be mitigated by operating the semiconductor switches in H-bridge inverters at optimized switching angles of the PWM signals. These switching angles can be achieved by deriving a number of nonlinear equations using Selective Harmonic Elimination Pulse Width Modulation (SHE-PWM) method. Modulation index (m) is a significant parameter used to control the amplitude of the fundamental output voltage of DC-AC inverter. By changing the value of modulation index the Total Harmonics Distortion (THD) also will change. In this paper, the performance of single phase full-bridge inverter using SHE-PWM scheme with varying the modulation index is evaluated. In order to achieve a minimum THD, a different number of nonlinear equations are used to calculate the switching angles. The performance of a single phase unipolar inverter is simulated in Matlab.

Effect of modulation index of pulse width modulation inverter on total harmonic distortion for sinusoidal

Knowing Total Harmonic Distortion (THD) content of voltage source inverter (VSI) is important and must be within the allowable range. Several schemes are suggested to mitigate THD and to produce as much a sinusoidal output signal as would be possible. One of such schemes is using a Sinusoidal Pulse Width Modulation SPWM-based inverter. SPWM is usually used in inverters for industrial applications. In this paper, a study of the performance of the SPWM technique is presented for a single phase H-bridge inverter. The SPWM scheme is modeled in MATLAB - Simulink. A bipolar and unipolar PWM technique are compared in this project as such techniques offer the features of effectively doubling the switching frequency of the output voltage. Under different conditions of modulation index, the pattern is utilized to estimate the harmonics. Simulation results for a full bridge single phase inverter using bipolar and unipolar SPWM schemes are presented.

Modulation Optimization Effect on Total Harmonic Distortion of Single Phase H-Bridge Inverter Based Selective Harmonics Elimination Technique

Specific odd harmonics can be mitigated by operating the simeconductor switches in H-bridge inverters at optimized switching angles of the PWM signals. These switching angles can be achieved by calculating a set of nonlinear equations using Selective Harmonic Elimination Pulse Width Modulation (SHE PWM) technique. Modulation index (m) is a significant parameter used to control the amplitude of the fundamental output voltage of DC-AC inverter. By changing the value of modulation index the Total Harmonics Distortion (THD) also will change. In this paper, the influence of varying modulation index on the THD, and the performance of H-bridge inverter using SHE PWM scheme is evaluated. To investigate the effect different conditions of modulation index and different number of nonlinear equations to calculate the switching angles to achieve a minimum THD, single phase H-bridge inverter is simulated in Matlab-Simulink.

Stepped Waveform Generation for Multilevel Inverter Topology Applications

This paper presents a review of the various inverter topologies, showing their utility in generating stepped waveform. The role of the PWM is highlighted in the operation of inverter for generating stepped-wave forms. The results show how similarly generated PWM used by different topologies can result into a stepped-waveform output capable of producing and AC closer to single fundamental component of 50Hz. The total harmonic Distortion (THD) is given for each set of simulation result with a relatively marked, though marginal utility, of the PWM used.