scholarly journals A Genetic-Based Hybrid Algorithm Harmonic Minimization Method for Cascaded Multilevel Inverters with ANFIS Implementation

2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Seyed Yahya Nikouei ◽  
Behzad Mirzaeian Dehkordi ◽  
Mehdi Niroomand
Keyword(s):  
Hybrid Algorithm ◽  
Pulse Width Modulation ◽  
Stochastic Methods ◽  
Switching Frequency ◽  
Harmonic Amplitude ◽  
Amplitude Equations ◽  
Minimization Method ◽  
Distortion Factor ◽  
Multilevel Inverters ◽  
Harmonic Elimination

Selective harmonic elimination pulse-width modulation (SHEPWM) is a widely adopted method to eliminate harmonics in multilevel inverters, yet solving harmonic amplitude equations is both time consuming and not accurate. This method is applied here for a 7-level cascaded multilevel inverter (CMLI) with erroneous DC sources. To meet the seven harmonic amplitude equations, two notches are applied with the use of higher switching frequency than nominal. These notches can be placed in six different positions in the voltage wave, and each was assessed in a separate manner. In order to solve the equations, a hybrid algorithm composed of genetic algorithm (GA) and Newton–Raphson (N-R) algorithm is applied to achieve faster convergence and maintain the accuracy of stochastic methods. At each step of the modulation index (M), different positions for the notches are compared based on the distortion factor (DF2%) benchmark, and the position with lowest DF2% is selected to train an artificial neural fuzzy interface system (ANFIS). ANFIS will receive the DC sources’ voltages together with required M and will produce one output; thus, eight ANFISs are applied to produce seven firing angles, and the remaining one is to determine which one of the notches’ positions should be used. Software simulations and experimental results confirm the validity of this proposed method. The proposed method achieves THD 8.45% when M is equal to 0.8 and is capable of effectively eliminating all harmonics up to the 19th order.

MSHE-PWM Control of Modular Multilevel Direct Current Transmission System

2015 ◽  
Vol 9 (1) ◽  
pp. 553-559
Author(s):  
HU Xin-xin ◽  
Chen Chun-lan
Keyword(s):  
Pulse Width Modulation ◽  
Reactive Power ◽  
Balance Control ◽  
Electric Energy ◽  
Access Point ◽  
Experimental Result ◽  
Switching Frequency ◽  
Pwm Control ◽  
Harmonic Elimination

In order to optimize the electric energy quality of HVDC access point, a modular multilevel selective harmonic elimination pulse-width modulation (MSHE-PWM) method is proposed. On the basis of keeping the minimum action frequency of the power device, MSHE-PWM method can meet the requirement for accurately eliminating low-order harmonics in the output PWM waveform. Firstly, establish the basic mathematical model of MMC topology and point out the voltage balance control principle of single modules; then, analyze offline gaining principle and realization way of MSHEPWM switching angle; finally, verify MSHE-PWM control performance on the basis of MMC reactive power compensation experimental prototype. The experimental result shows that the proposed MSHE-PWM method can meet such performance indexes as low switching frequency and no lower-order harmonics, and has verified the feasibility and effectiveness thereof for optimizing the electric energy quality of HVDC access point.

scholarly journals Experimental validation of new self-voltage balanced 9L-ANPC inverter for photovoltaic applications

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
M. Jagabar Sathik ◽  
Dhafer J. Almakhles ◽  
N. Sandeep ◽  
Marif Daula Siddique
Keyword(s):  
Output Voltage ◽  
Pulse Width Modulation ◽  
Superior Performance ◽  
Modulation Scheme ◽  
Switching Frequency ◽  
Switched Capacitor ◽  
Renewable Energy Resources ◽  
High Quality ◽  
Multilevel Inverters ◽  
Blocking Voltage

AbstractMultilevel inverters play an important role in extracting the power from renewable energy resources and delivering the output voltage with high quality to the load. This paper proposes a new single-stage switched capacitor nine-level inverter, which comprises an improved T-type inverter, auxiliary switch, and switched cell unit. The proposed topology effectively reduces the DC-link capacitor voltage and exhibits superior performance over recently switched-capacitor inverter topologies in terms of the number of power components and blocking voltage of the switches. A level-shifted multilevel pulse width modulation scheme with a modified triangular carrier wave is implemented to produce a high-quality stepped output voltage waveform with low switching frequency. The proposed nine-level inverter’s effectiveness, driven by the recommended modulation technique, is experimentally verified under varying load conditions. The power loss and efficiency for the proposed nine-level inverter are thoroughly discussed with different loads.

scholarly journals Multicarrier PWM Strategies for Hybrid Symmetrical Multilevel Inverter with Reduced Switch Count

2020 ◽  
Vol 9 (5) ◽  
pp. 860-866
Keyword(s):  
Electromagnetic Interference ◽  
Output Voltage ◽  
Pulse Width Modulation ◽  
Harmonic Distortion ◽  
Multilevel Inverter ◽  
Total Harmonic Distortion ◽  
Switching Frequency ◽  
Third Harmonic ◽  
Multilevel Inverters ◽  
High Switching Frequency

Multilevel inverters are widely used for high power and high voltage applications. The performance of multilevel inverters are superior to conventional two level inverters in terms of reduced total harmonic distortion, higher dc link voltages, lower electromagnetic interference and increased quality in the output voltage waveform. This paper presents a single phase hybrid eleven level multilevel inverter topology with reduced switch count to compensate the above mentioned disadvantages. This paper also presents various high switching frequency based multi carrier pulse width modulation strategies such as Phase Disposition PWM Strategy (PDPWM), Phase Opposition and Disposition PWM Strategy (PODPWM), Alternate Phase opposition Disposition PWM (APODPWM), Carrier Overlapping PWM (COPWM), Variable frequency carrier PWM (VFPWM), Third Harmonic Injection PWM (TFIPWM) applied to the proposed eleven level multilevel inverter and is analyzed for RL load. FFT analysis is carried out and total harmonic distortion, fundamental output voltage are calculated. Simulation is carried out in MATLAB/SMULINK.

scholarly journals Research on hybrid SHEPWM based on different switching patterns

2019 ◽  
Vol 10 (4) ◽  
pp. 1875 ◽  
Author(s):  
Tao Jing ◽  
Alexander Maklakov ◽  
Andrey Radionov ◽  
Sergei Baskov ◽  
Aleksandra Kulmukhametova
Keyword(s):  
Pulse Width ◽  
Pulse Width Modulation ◽  
Effective Means ◽  
Switching Frequency ◽  
Harmonic Elimination ◽  
Switching Patterns ◽  
Control Scheme ◽  
Selective Harmonic Elimination ◽  
Simulation Results ◽  
Additional Hardware

<span>This paper presents a hybrid pulse width modulation (HPWM) strategy based on different switching patterns of selective harmonic elimination pulse width modulation (SHEPWM) for the three-level neutral point clamped (3L-NPC) converter. Specific low-order harmonics can be eliminated by SHEPWM at low switching frequency, while the remaining high-order harmonics can be selected to be simply filtered by additional hardware. Large oscillation waveform usually occurs in the transition instant between two diverse modulation situations, therefore switching between distinct switching patterns can be problematic if no effective means is taken, especially when the effect of smooth and fast transition at any time is considerable. A universal and valid control strategy, which maintains the high-quality output voltage and current, is proposed and implemented in this paper to address this issue. Simulation results obtained from MATLAB/SIMULINK are presented to analyze the performance and validate the feasibility and effectiveness of this control scheme.</span>

New Selective Harmonic Elimination-Pulse-Width Modulation for Cascaded H-bridge Multilevel Inverters

2018 ◽  
Vol 19 (5) ◽  
Author(s):  
Piyush L. Kamani ◽  
Mahmadasraf A. Mulla
Keyword(s):  
Real Time ◽  
Pulse Width ◽  
Output Voltage ◽  
Pulse Width Modulation ◽  
Experimental Studies ◽  
Equal Area ◽  
Multilevel Inverters ◽  
Harmonic Elimination ◽  
Selective Harmonic Elimination ◽  
Selection Of

AbstractThis paper presents a univariate equation-based selective harmonic elimination-pulse-width modulation (USHE-PWM) method for cascaded H-bridge (CHB) multilevel inverters (MLIs). Using equal-area criteria, the selection of voltage rating of dc-links have been done. The output voltage is controlled by inserting switching notch at the centre of each level of output voltage. Instead of conventional transcendental SHE-PWM equations, all these calculations are accomplished using univariate equations. This simplifies the real-time implementation of the proposed method greatly, even for the MLI with a large number of levels. The USHE-PWM method can eliminate more harmonics compared with the conventional SHE-PWM methods. While controlling the output voltage, the harmonic pattern remains unaffected. The validity of the proposed method is confirmed by the simulation and experimental studies.

scholarly journals Analysis of a switching angle calculation by ANN for nine level inverter apply into experimental case study with elimination of lower and higher order harmonics

2020 ◽  
Vol 20 (2) ◽  
pp. 948
Author(s):  
Mohammed Rasheed ◽  
Rosli Omar ◽  
Marizan Sulaiman ◽  
Wahidah Abd Halim ◽  
Moataz M.A. Alakkad
Keyword(s):  
Output Voltage ◽  
Pulse Width Modulation ◽  
Harmonic Distortion ◽  
Digital Signal ◽  
Multilevel Inverters ◽  
Ac Drive ◽  
Harmonic Elimination ◽  
Bus Voltage ◽  
Design And Testing

This paper confers an investigation of a Selective Harmonic Elimination (SHE) technique has gained wide acceptance for many AC drive applications, due to a higher DC bus voltage utilization (higher output voltage compared with the Sinusoidal Pulse Width Modulation (SPWM), lower harmonic distortions and easy digital realization.” In recent years, the SHE technique was extensively adopted in multilevel inverters since it offers greater numbers of switching for obtaining further improvements of AC drive performances. “Nevertheless, the use of SHE-associated multilevel inverters will optimize the switching angles based on Artificial Neural Networks (ANN) compared with Particle Swarm Optimization (PSO) to reduce the Total Harmonic Distortion (THD) of the modified CHB-MLI output voltage within permissible limits. The main objectives of this paper are the design and testing of the CHB-MLI modified topology laboratory for a nine-level single-phase prototype.” Also demonstrated were the experimental effects of using Digital Signal Processing (DSP) TMS320F2812 into a prototype. The controls were applied to the modified multilevel inverter, based on ANN and PSO. The proposed controller was then coded onto a board of DSP TMS320F2812. Compared with the PSO method, the inverter gives fewer THD using ANN scheme.

scholarly journals Performance Evaluation of Eleven-Phase Induction Machine with Different PWM Techniques

2015 ◽  
Vol 12 (1) ◽  
pp. 1
Author(s):  
M.I. Masoud ◽  
A.S. Abdelkhalik
Keyword(s):  
Comparative Study ◽  
Pulse Width Modulation ◽  
Induction Machine ◽  
Single Pulse ◽  
Torque Ripple ◽  
Switching Frequency ◽  
Pulse Modulation ◽  
Medium Voltage ◽  
Harmonic Elimination ◽  
Power Switches

Multiphase induction machines are used extensively in low and medium voltage (MV) drives. In MV drives, power switches have a limitation associated with switching frequency. This paper is a comparative study of the eleven-phase induction machine’s performance when used as a prototype and fed sinusoidal pulse-width-modulation (SPWM) with a low switching frequency, selective harmonic elimination (SHE), and single pulse modulation (SPM) techniques. The comparison depends on voltage/frequency controls for the same phase of voltage applied on the machine terminals for all previous techniques. The comparative study covers torque ripple, stator and harmonic currents, and motor efficiency. 

scholarly journals Modeling and Compensation for Dead-Time Effect in High Power IGBT/IGCT Converters with SHE-PWM Modulation

Energies ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 4348 ◽  
Author(s):  
Jingling Cheng ◽  
Dongdong Chen ◽  
Guozhu Chen
Keyword(s):  
High Power ◽  
Pulse Width Modulation ◽  
Power Converters ◽  
Dead Time ◽  
Open Loop ◽  
Time Effect ◽  
Operating Conditions ◽  
Switching Frequency ◽  
Harmonic Elimination ◽  
The Dead

Research on applying selective harmonic elimination pulse width modulation (SHE-PWM) to high power converters has drawn tremendous interest, due to the advantages of low switching frequency and high output harmonic performance. In the fields of high power converters such as variable speed traction motor drives and static synchronous compensators (STATCOM), the adoption of high voltage but slow speed semiconductor devices, i.e., IGBT/IGCT, results in a longer dead time of several microseconds, which leads to a motor vibration in the former case or the distortion of grid current in the latter case. This paper analyzes in detail the mechanism of the dead-time effect on 3-level SHE-PWM with different operating conditions considered. For the first time, a general mathematical model describing the relationship between the dead time and harmonic distribution of SHE-PWM wave is established. Based on which an open-loop compensation method by inserting a margin time into the effective switching angles is proposed. Furthermore, a closed-loop controller that implements online adaptive adjustment of the margin time is designed in case of a variable frequency application. The effectiveness of the proposed method in different scenarios is verified through simulation results.

scholarly journals Application of SHEPWM in Helicopter Transient Electromagnetic Based on the Subsection Control Approach

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Lihui Gao ◽  
Shengbao Yu ◽  
Chunxia Jiang ◽  
Nan Chen ◽  
Renhui Chen ◽  
...  
Keyword(s):  
Mirror Symmetry ◽  
Pulse Width Modulation ◽  
High Efficiency ◽  
Switching Frequency ◽  
Detection Accuracy ◽  
Switching Loss ◽  
Control Approach ◽  
Time Frequency ◽  
Transient Electromagnetic ◽  
Harmonic Elimination

Guaranteeing the quality of the transmitting current under low switching frequency conditions is the crucial point in the helicopter transient electromagnetic (HTEM) system which affects the efficiency and exploration accuracy. HTEM requires high efficiency and low switching loss of the inverter power supply due to the facts that HTEM uses air-launched and air-received measurement methods, and the power storage capacity of the airborne transmitting system is limited. Paradoxically, low switching frequency directly affects the transmitting waveform quality and thereby affects the detection accuracy. In this study, we present a semiperiodic mirror symmetry selective harmonic elimination pulse width modulation (SHEPWM) based on the subsection control approach to balance transmitting current quality and switching loss. In the SHEPWM method, the semiperiodic mirror symmetry SHEPWM nonlinear equations are established by the time frequency domain information of the inverter output voltage and resolved by the artificial neural network (ANN) algorithm to attain switching time sequence of desired transmitting current. The simulation and experimental results verify the effectiveness of the SHEPWM subsection control strategy, which can reduce the switching loss while ensuring the current waveform quality and detection accuracy.

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