scholarly journals Harmonics reduction of a five-level inverter by unbalanced carriers and over-modulation techniques

2018 ◽  
Vol 7 (3) ◽  
pp. 1059
Author(s):  
Mustafa Fawzi Mohammed ◽  
Ali Husain Ahmad ◽  
AbdulRahim Thiab Humod
Keyword(s):  
Fundamental Frequency ◽  
Output Voltage ◽  
Single Phase ◽  
Harmonic Distortion ◽  
Total Harmonic Distortion ◽  
Modulation Method ◽  
Labview Software ◽  
Design And Implementation ◽  
Modulation Techniques ◽  
Multi Level

The most concerns in the inverter's design are about, how to make the output voltage of the inverter sinusoidal at the desired fundamental frequency with low total harmonic distortion (THD). This paper presents a design and implementation of single-phase five-level inverter which is powered by single dc source and based on T-type multi-level inverters construction. The proposed inverter is built mainly by six IGBTs and two diodes. The used modulation technique is based on using two triangular carriers at 2000 Hz frequency and shifted by phase opposition disposition (POD) method. The carriers are made slightly unbalanced with their amplitudes. The over-modulation method is also introduced in the design to get the lowest possible THD effect without using filters. The inverter is simulated by MATLAB SIMULINK, implemented practically, and tested with the help of LabVIEW software.  

scholarly journals Comparison of multiple modulation techniques for various topologies of multilevel converters for single phase AC motor drive

2019 ◽  
Vol 10 (2) ◽  
pp. 662
Author(s):  
Laith M. Akram Alsaqal ◽  
Ahmed M. T. Ibraheem Alnaib ◽  
Omar Talal Mahmood
Keyword(s):  
Output Voltage ◽  
Single Phase ◽  
Modulation Frequency ◽  
Harmonic Distortion ◽  
Modulation Method ◽  
Motor Drive ◽  
Comparison Study ◽  
Multilevel Converters ◽  
Performance Factors ◽  
Modulation Techniques

There are various types of Multilevel Converters (MCs) in addition to various types of modulation techniques for these types of MCs; the challenges in selecting the best one of them with regard to the amount of the required of components, and its harmonics content. So, a comparison study among these types has been done in this paper. For comparison study, the simulation of seven level of two popular topologies of MCs: Neutral Point Clamped (NPC) converter, and Cascaded-MCs were carried out with Matlab/Simulink software program. These converters are used to drive a single phase capacitor start motor drive. Multicarrier modulation control techniques are used for controlling the MCs; these techniques involve two main type: Level Shifted Carrier (LSC), and Phase Shifted Carrier (PSC). The comparison is made with respect to the performance factors as, the amplitude of  the Total Harmonic Distortion (THD), and the DC-bus utilization performance which measured by Root Mean Square of the output voltage Vrms at variable modulation indices and variable carrier frequency. Based on simulation results it's found, that the cascaded-MC with PSC modulation method gives best results, in addition to the Alternative Phase Opposition Disposition APOD-LSC modulation technique (with even number of modulation frequency) generate the output voltage with a lower harmonic content compared with the other techniques.

A Overlapping Carrier Based SPWM for a 5-Level Cascaded H-bridge Multilevel Inverter

2016 ◽  
Vol 1 (2) ◽  
pp. 221
Author(s):  
Kureve D. Teryima ◽  
Goshwe Y. Nentawe ◽  
Agbo O. David
Keyword(s):  
Pulse Width ◽  
Single Phase ◽  
Pulse Width Modulation ◽  
Harmonic Distortion ◽  
Switching Control ◽  
Multilevel Inverter ◽  
Total Harmonic Distortion ◽  
Control Technique ◽  
Control Techniques ◽  
Multi Level

<p>This paper proposes a switching control for a cascaded H-bridge inverter structure with reduced switches which is used to improve the THD performance of a single phase five level CHB MLI. The multi level inverter is simulated for the conventional carrier overlapping APOD and the proposed carrier overlapping APOD Pulse Width Modulation (PWM) switching control technique. The total harmonic distortion (THD) of the output voltages are observed for both PWM control techniques. The performance of the symmetric CHB MLI is simulated using MATLAB-SIMULINK. It is observed that the proposed carrier overlapping APODPWM provides output with relatively low THD as compared to the conventional carrier overlapping APODPWM.</p>

scholarly journals Control of Cascaded H-Bridge Multilevel Inverter Based on Optimum Regulation of Switching Angles, and the FPGA Implementation

2019 ◽  
Vol 3 (1) ◽  
Author(s):  
Hatef Firouzkouhi
Keyword(s):  
Output Voltage ◽  
Harmonic Distortion ◽  
Fpga Implementation ◽  
Multilevel Inverter ◽  
Total Harmonic Distortion ◽  
Switching Pattern ◽  
Multi Level ◽  
Simulation Results ◽  
Polynomial Term

A new concept in control of cascaded H-Bridge multi-level inverters is proposed in this paper. According to this concept, switching angles are considered to be independent from the fundamental voltage. A polynomial term is presented to show the relation between switching angles and DC voltages. Based on this concept, Total Harmonic Distortion (THD) calculations are updated and proved to be independent from the fundamental voltage. Thus, once calculated for minimum THD, the switching pattern can be used for any required level of output voltage. To examine the effectiveness of the proposed method, it is applied in control of an eleven level inverter. The simulation results are demonstrated and verified through experiments with a setup controlled by Xilinx SPARTAN3 family FPGA (XC3S400-PQG208).

A Overlapping Carrier Based SPWM for a 5-Level Cascaded H-bridge Multilevel Inverter

2016 ◽  
Vol 7 (2) ◽  
pp. 349 ◽  
Author(s):  
Kureve D. Teryima ◽  
Goshwe Y. Nentawe ◽  
Agbo O. David
Keyword(s):  
Pulse Width ◽  
Single Phase ◽  
Pulse Width Modulation ◽  
Harmonic Distortion ◽  
Switching Control ◽  
Multilevel Inverter ◽  
Total Harmonic Distortion ◽  
Control Technique ◽  
Control Techniques ◽  
Multi Level

This paper proposes a switching control for a cascaded H-bridge inverter structure with reduced switches which is used to improve the THD performance of a single phase five level CHB MLI. The multi level inverter is simulated for the conventional carrier overlapping APOD and the proposed carrier overlapping APOD Pulse Width Modulation (PWM) switching control technique. The total harmonic distortion (THD) of the output voltages are observed for both PWM control techniques. The performance of the symmetric CHB MLI is simulated using MATLAB-SIMULINK. It is observed that the proposed carrier overlapping APODPWM provides output with relatively low THD as compared to the conventional carrier overlapping APODPWM.

scholarly journals Modified Cascaded H-Bridge Multilevel Inverter using Trinary DC source

2018 ◽  
Vol 7 (2.24) ◽  
pp. 55
Author(s):  
Anuja Prashant Diwan ◽  
N Booma Nagarajan ◽  
T Murugan ◽  
S Ashrafudeen ◽  
G J. Jenito Paul
Keyword(s):  
Output Voltage ◽  
Single Phase ◽  
Harmonic Distortion ◽  
Multilevel Inverter ◽  
Total Harmonic Distortion ◽  
Voltage Source ◽  
Matlab Simulink ◽  
Switching Losses ◽  
Switching Pattern ◽  
Cascaded Multilevel Inverter

In this paper, single phase nine level cascaded multilevel inverter using trinary voltage source is described. Normally for getting nine level MLI output, four H-Bridges are required. But in proposed method, nine level output is achieved by using two H-Bridges only. Performance of Multilevel inverter is improved by using modular switching pattern. This method reduces the number of switches to the half and thus reduces switching losses. Since the number of levels at the output voltage is increased, Total Harmonic Distortion (THD) gets reduced significantly. This presents simple configuration is simple and can be controlled easily. MATLAB-SIMULINK is used to validate the results of proposed technic, simulation is carried out using. The proposed method has been exhaustively compared with classical cascaded H-Bridge topology. 

scholarly journals Total Harmonic Distortion Oriented Finite Control Set Model Predictive Control for Single-Phase Inverters

Energies ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 3467 ◽  
Author(s):  
Po Li ◽  
Ruiyu Li ◽  
Haifeng Feng
Keyword(s):  
Model Predictive Control ◽  
Cost Function ◽  
Predictive Control ◽  
Single Phase ◽  
Tracking Error ◽  
Harmonic Distortion ◽  
Total Harmonic Distortion ◽  
Finite Control ◽  
Control Set ◽  
The Cost

Inverters are commonly controlled to generate AC current and Total Harmonic Distortion (THD) is the core index in judging the control effect. In this paper, a THD oriented Finite Control Set Model Predictive Control (FCS MPC) scheme is proposed for the single-phase inverter, where a optimization problem is solved to obtain the switching law for realization. Different from the traditional cost function, which focuses on the instantaneous deviation of amplitude between predictive current and its reference, we redesign a cost function that is the linear combination of the current fundamental tracking error, instantaneous THD value and DC component in one fundamental cycle (for 50 Hz, it is 0.02 s). Iterative method is developed for rapid calculation of this cost function. By choosing a switching state from a FCS to minimize the cost function, a FCS MPC is finally constructed. Simulation results in Matlab/Simulink and experimental results on rapid control prototype platform show the effect of this method. Analyses illustrate that, by choosing suitable weight of the cost function, the performance of this THD oriented FCS MPC method is better than the traditional one.

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