Sinusoidal Pulse Width Modulation Technique Research Articles

Bipolar DC output fed grounded DC-AC converter for photovoltaic application

Introduction. In recent years the usage of electricity has increased tremendously as the electrical needs and loads got increased. Hence the researchers focused on the electricity generation from renewable sources in order to promote sustainable green environment. Owing to the lesser cost and more reliable high efficiency system with reduced use of equipments became prominent for the grid connected photovoltaic single phase systems. The novelty of this proposed converters are to reduce total power loss and to analyze the performance of the converter under various modulation index and to have lesser harmonics using sinusoidal pulse width modulation technique for both T-type and F-type inverter. Interest of the work is to merge two DC-DC converters which have same output voltage in order to have transformer less utilization of power. This has given pathway to develop a new DC-DC converter network by merging the common input nodes of CUK and SEPIC converter. Purpose. This similar structure of both converters made it easy to combine the input stages of and to get bipolar output. Methods. Here we can get bipolar output without the utilization of transformer which minimizes the overall size of the proposed system. In this paper, a combined CUK-SEPIC based grid connected transformerless inverter for photovoltaic application is suggested. Results. The suggested converter is simulated using MATLAB and the results were discussed. Further the circuit is extended with a 1 kW F-type inverter to demonstrate grid connection of the converter. Practical value. This converter can be implemented for photovoltaic applications for obtaining the bipolar DC output from the DC source.

MATLAB-Simulink environment based power quality improvement in photovoltaic system using multilevel inverter

Introduction. In this world of technical advancement, conventional resources are at the stage of destruction. To avoid such problems, we are going to use an alternative energy source namely solar by photovoltaic effect. The demand for multilevel inverters increased as they are used for different dynamic (high) voltage and dynamic (high) power appliances as they are capable of producing the output wave shape with low total harmonic distortion. Novelty. A new multilevel inverter is used in adding a (bidirectional) two way switch in between the capacitor and a traditional H-bridge module. This produces a better sine wave. By series connection of these two H-bridge modules, nine levels output voltage including zero is possible. The purpose of the proposed topology is reduction in the number of switches and it gives the good result with comparatively less power loss when it is compared with the other normal basic traditional inverters of the same output quality. Methods. In this paper, sinusoidal pulse width modulation technique is used for the working of the switches in the multilevel inverter. The results are verified by using simulation and also experimental setup is done. From the results it is observed that the proposed topology with reduced number of switches gives lower electromagnetic interference, lower harmonic distortion. Practical value. The total harmonic distortion value in the simulation is 14.4 % and practically it is 13.8 %.

A Comparative Study of Total Harmonic Distortion betweenTwo Topologies 27- and 31 Multi Level Inverter

In recent times, Multilevel inverters are considered an essential component of power electronics with widespread use in a wide range of high-voltage and high-power industrial and commercial applications. The use of multi-level inverters, also known as MLIs, has been preferred over conventional inverters due to the characteristics that these MLIs possess. These characteristics include low harmonic distortion caused by satisfacory performance of MLIs. This paper is concerned with analyzing harmonics to gain a deeper understanding of the performance of cascaded H-Bridge multilevel inverters (CHB-MLI). The model was constructed by using MATLAB/SIMULINK. A comparison was made between an asymmetrical cascaded 27 and 31-level multi-level inverter (MLI) by using the Phase disposition sinusoidal Pulse Width Modulation (PD-SPWM)and Phase Opposition Disposition sinusoidal Pulse Width Modulation (POD-SPWM) techniques. According to the outcomes of the simulations, 31 levels are better than 27 where Total Harmonic Distortion ( THD) in 31 levels is lower than 27 levels. The best result obtained during this study is 31 levels that use (PD-SPWM) technology, where the percentage of total harmonic distortion is small compared to the rest of the results and equal to 3.63%.

Multi-Level Inverter Fed Induction Motors Based on Simplified and Efficient Modulation Techniques

Speed control of three phase and single phase induction motors represents a very important issue in residential and industrial applications. This paper presents a voltage to frequency speed control of both single phase and three phase induction motors derived by multi-level inverters (MLIs). 15-level and 31-level multi-level inverters are considered. Both MLIs are operated by applying two proposed simplified and efficient modulation techniques in addition to the application of conventional multicarrier sinusoidal pulse width modulation technique MC-SPWM. The proposed modulation techniques overcome several difficulties related to MC-SPWM. The scaler voltage to frequency control method operates very well during starting along with step changes in motor speeds. Simulation results verify the high performance of the proposed modulation techniques when controlling both induction motors based on 15-level and 31-level MLIs.

Performance of 7-level cascade H-bridge multi level inverter driven induction motor drive

In recent times, many of industrial applications require smooth control over a wide range of speeds or smooth torque control without effecting motor performance and efficiency. So, cascaded H-Bridge multilevel inverters convert the low or medium level voltage to medium or high level of output voltages. In this paper, a cascaded H-Bridge multilevel seven level inverter is operated by using sinusoidal pulse width modulation technique. This PWM technique will improves the smoothness of waveform by reducing the lower order harmonics. And analysed its performances like speed, torque, THD etc.

Performance evaluation of grid connected photovoltaic system using novel HTLB-WOA regulated VPFOTADF controller

The aim of this manuscript is the design of Hybrid Teaching Learning Based-Whale Optimization Algorithm -Variable Parameter Fractional Order Tilt Acceleration Derivative with Filter (HTLB-WOA regulated VPFOTADF) controller to reduce the harmonic distortion and improving performance of grid connected solar photovoltaic system. The solar photovoltaic system consists of components like photovoltaic array, interleaved fractional order boost converter, Reduced Switch Multilevel Inverter (RSMI) and HTLB-WOA regulated VPFOTADF controller. Interleaved fractional order boost converter is preferred over boost converter because of its low ripple voltage, faster transient response, high efficiency, low duty cycle, reduced EMC and improved reliability and stability. In this control strategy the control logic is formulated by using a Tilt Integral Derivative Controller (TIDC), whose control parameters are considered as a function of error to improve the robustness. The validation, better performance and superiority of HTLB-WOA regulated VPFOTADF is established by comparative result analysis with other state of the art controllers. HTLB-WOA regulated VPFOTADF along with Direct and Quadrature Control based Sinusoidal Pulse Width Modulation (DQC-SPWM) technique is implemented in this manuscript. This proposed model is analyzed for reduction in harmonic, improved system performance, better accuracy, improved stability, improved robustness and better capabilities to handle system uncertainties.

Improved Seven-Level Multilevel DC-Link Inverter with Novel Carrier PWM Technique

Multilevel inverters have emerged as a viable alternative for various power electronic applications. It offers significant features in terms of reduced total harmonic distortion (THD) due to more number of output voltage levels, lower filter size, and voltage stress and reduced switching losses when compared to conventional two-level inverters. The classical topologies such as neutral point clamped, flying capacitor and cascaded H-bridge (CHB) are very popular for industrial applications. All these topologies have limitations in terms of more component count, capacitor voltage balancing for increased number of voltage levels. In this regard, multi-level DC link (MLDCL) inverter has been introduced as an improvement with respect to CHB MLI in terms of reduced switch count and is considered here for the study. This paper presents a single-phase MLDC link inverter with a modified carrier-based level-shifted phase disposition sinusoidal pulse width modulation (LS-PD-SPWM) technique. The proposed novel carrier PWM is compared with the conventional modulation techniques in terms of THD. The performance of the proposed modulation technique is analyzed through simulation studies in MATLAB software. A laboratory prototype model is developed in order to validate the experimental results.

A New Transformer-Less Single-Phase Photovoltaic Inverter to Improve the Performance of Grid-Connected Solar Photovoltaic Systems

Photovoltaic (PV) energy systems have found diverse applications in fulfilling the increasing energy demand worldwide. Transformer-less PV inverters convert the DC energy from PV systems to AC energy and deliver it to the grid through a non-isolated connection. This paper proposes a new transformer-less grid-connected PV inverter. A closed-loop control scheme is presented for the proposed transformer-less inverter to connect it with the power grid. The proposed transformer-less inverter reduces extra leakage current and holds the common-mode voltage at a constant point. To eliminate extra leakage current, as well as achieve constant common-mode voltage, a midpoint clamping method is utilized to operate the inverter. The proposed transformer-less inverter is formed of seven insulated gate bipolar transistors (IGBTs) employing a unipolar sinusoidal pulse width modulation (SPWM) technique for switching purposes. An LCL filter is employed to reshape the two-level inverter output voltage and current to obtain closer sinusoidal waveforms. The output voltage and current total harmonic distortion (THD) of the proposed transformer-less inverter were found to be 1.25% and 0.94%, respectively, in the grid-connected mode. The leakage current elimination mechanism with the proposed transformer-less inverter is deeply analyzed in this paper. The performances of the proposed transformer-less inverter were evaluated with MATLAB/Simulink simulation and validated in a laboratory scale experiment.

A Novel Application of Random Hysteresis Current Control: Acoustic Noise and Vibration Reduction of a Permanent Magnet Synchronous Motor Drive

This article presents a novel application of the random hysteresis current control (RHCC) technique on a permanent magnet synchronous motor (PMSM) drive to reduce acoustic noise and vibration (ANV). The proposed RHCC approach brings a significant reduction in torque ripples and ANV in the motor, thereby enhancing the performance of the complete drive system under operation. Among various available spread-spectrum techniques, RHCC has recently applied to unipolar and bipolar pulsewidth modulation (PWM)-fed power electronics converters to reduce harmonics in voltage and currents, with promising results. Furthermore, in-depth theoretical background and analysis of the performance of RHCC in reducing the torque ripples, vibration, and acoustic noise of a PMSM drive are presented. Appropriate simulation as well as experimental analysis have been carried out. The results show a substantial reduction of ANV in a PMSM drive through the proposed RHCC technique. The performance of the proposed method is compared with pseudorandom triangular PWM, hysteresis current control (HCC), and sinusoidal PWM (SPWM) techniques.

Multioutput Hybrid Solar Inverter With No Right Half-Plane Zero and Reduced Common-Mode Leakage Current

In this article, a multioutput-based transformerless hybrid solar inverter (TLHSI) with no right half-plane zero (RHPZ) and reduced common-mode leakage/ground current is presented for photovoltaic (PV) based microgrid applications. In the proposed multioutput TLHSI, two magnetically coupled inductor coils are placed between the input and dc output sides along with a dc-link capacitor to continuously provide the stored energy to the dc load so that the RHPZ is eliminated and, thus, makes it a minimum phase system. Furthermore, a hybrid unipolar sinusoidal pulsewidth modulation technique is established to nullify the high-frequency components of common-mode voltage across the PV to ground stray capacitor. Also, it normalizes both dc and ac loads at the same instant from a single dc input during each operating state of the proposed TLHSI. The shoot-through issue is resolved in the proposed TLHSI, which increases the system reliability. Furthermore, as the deadtime is not required in between the switching pulses, the quality of the inverter output voltage improves. The performance analysis of the proposed TLHSI is compared with the existing topologies. To validate the performance of TLHSI, a scaled down 340 W laboratory prototype is developed.

A Switched Capacitor-Based Multilevel Boost Inverter for Photovoltaic Applications

In this paper, a single-phase 13-level switching capacitor multilevel boost inverter (SCMLBI) with less switches and a voltage boost gain of six times is presented. The main focus of this work is to present a single DC source SCMLBI topology, which can provide an AC output voltage with low harmonic distortion by suitable sinusoidal pulse modulation (SPWM) technique. The given SCMLBI boost topology is designed to provide 13 output voltage levels utilizing a single DC source and 14 power electronic switches, and it includes intrinsic capacitor self-voltage balancing. The presented SCMLBI inverter does not require any magnetic elements like inductors which do not make the system complex in IC fabrication. In this work, the DC source is provided with a solar PV array with maximum power point tracking (MPPT) algorithm. The proposed SCMLBI topology provides an output voltage larger than the input voltage by appropriately converting the capacitors in series and parallel combinations. Sinusoidal PWM technique is used to control the switches in SCMLBI. A solar PV array of 100 W with incremental and conductance MPPT algorithm is used in this work. The verification of the presented SCMLBI topology is simulated on MATLAB software. Hardware results are also presented for the validation of SCMLBI topology.

Modified unipolar SPWM inverter for solar PV applications using MATLAB/Simulink model interfaced with dSPACE DS1104

PurposeThe purpose of this paper is to check the Solar Photovoltaic (PV) inverter working condition with modified unipolar switching pulse. The gate pulse for the inverter switches is generated in MATLAB simulation and interfaced with hardware protype. Simulation results can be compared with hardware results.Design/methodology/approachA considerable amount of research has been done on different Pulse Width Modulation (PWM) techniques. Based on the findings, a modified Unipolar Sinusoidal PWM technique was created with one reference signal and two carrier signals+ (one for the positive half cycle and the other for the negative half cycle) and simulated in the MATLAB/Simulink platform. The prototype inverter module receives the simulated switching pulses via dSPACE DS1104 hardware software interfacing board. The hardware implementation has been done, and the hardware results compared with simulation results for various input voltage levels using resistive load.FindingsThis modified switching pulse has dead band and additional hardware setup is not required. 3-phase multi-level inverter output waveform has been achieved with six switches in this method and with low filter values, pure sine wave output can be obtained in simulation. By this method of switching pulse generation and testing, for every modification in switching pulse hardware gate driver is not required. Resulting time consumption and money investment are lower.Originality/valueModified Unipolar SPWM pulse generation technique is novel method for solar PV inverter. The switching pulse has been designed and tested in both MATLAB/Simulation and hardware prototype inverter. Hardware and software results are identical. This method of pulse generation and hardware implementation has not been done anywhere before.

Design and Implementation of a Single-Source 17-Level Inverter for a Single-Phase Transformer-Less Grid-Connected Photovoltaic Systems

Transformer-less multilevel inverters (MLIs) based on switched capacitors are gaining importance due to the voltage boosting ability from a single-input DC source and inherent capacitor voltage balancing capability. Most of the grid-connected transformer-less inverters are five-level and are commonly grounded so that their leakage current is zero. However, some major challenges like higher total standing voltage (TSV), more losses due to capacitor voltage ripples, higher charging current, and peak VA rating of the switches are comparatively higher. The motivation of the proposed work is to reduce the voltage ripple across the capacitors, minimum TSV, higher efficiency close to 98% at 1 kW, and lower cost. By using a modified sinusoidal pulse width modulation (SPWM) technique for the proposed single-phase 17-level inverter, a transformer-less grid-interfacing can be realized as the leakage current is (≈22 mA) well within the acceptable value (<300 mA) and is independent of the switching frequency. To validate the performance of the proposed structure, its performances are compared with the recently developed transformer-less inverters. The experimental prototype of a 1-kW single-phase 17-level inverter is designed and tested for grid-connected and standalone mode, and the corresponding results are verified.

Modelling and Control Development of a Cascaded NPC-Based MVDC Converter for Harmonic Analysis Studies in Power Distribution Networks

Today’s power distribution networks are predicted to incorporate more Power Electronics (PE)-based power conversion systems, widely acknowledged as harmonic sources. Concerns about power harmonic severity in the distribution networks can arise, especially with the growing numbers of Medium Voltage Direct Current (MVDC) systems, which are also facilitated by such power converters. Yet, an accurate harmonic model of the MVDC converter is required to investigate its harmonic emissions, propagations, effects, and solutions in today’s distribution networks. This article is devoted to the development of a detailed model of a cascaded Neutral Point-Clamped (NPC)-based MVDC converter for accurate harmonic analysis studies. An appropriate control system with a simple Proportional Integral (PI) controller tuned using the loop-shaping technique is developed. An interleaved Sinusoidal Pulse-Width Modulation (SPWM) scheme aiming to improve the harmonic performance of such an application is introduced. The detailed model of the MVDC system was developed using the Simulink/MATLAB simulation environment, for which the concept of operation was validated, control system performance was investigated, and the effectiveness of the harmonic reduction method was analysed. The key finding is that the interleaved SPWM technique has significantly reduced the Total Harmonic Distortion (THD) to 2% with no significant even-order harmonic components in comparison to the reported models.

Selective Harmonic Elimination for Variable Frequency Traction Motor Drives Using Harris Hawks Optimization

In this article, Harris hawks’ optimization (HHO) for selective harmonic elimination method (SHEM) of a voltage source inverter has been applied to a traction motor drive for light rail transportation. The main objective of SHEM's pulsewidth modulation (PWM) strategy is to remove the low-order harmonics by solving nonlinear equations while satisfying the required fundamental component's magnitude. The HHO applied in this article to a two-level, three-phase inverter aims at solving the associated nonlinear equations with a high accuracy and convergence probability as a strong metaheuristic algorithm. SHEM simulations are carried out via MATLAB/Simulink on a 125 kW traction motor drive platform for various SHEM angles to verify its performance in comparison with the SHEM with sinusoidal PWM (and space vector modulation (SVM) techniques. Experimental results obtained on a physical simulator of the light rail transportation system in the laboratory have shown remarkable findings in view of the dc-link voltage magnitude on the performance of the associated traction motor drive. In the light of different fundamental frequency operations, number of SHEM angles, and operating dc-link voltages, a general evaluation of the SHEM has been made in considering its application to a light rail traction motor drive. It has also been shown that the application of online SHEM on a GPU framework is possible in real-time.

Compact Quadratic Boost Switched-Capacitor Inverter

This article presents a new topology for a single-stage nine-level (9L) switched-capacitor inverter. The structure of the proposed topology is not only simple but also compact. The proposed topology is developed with self-voltage balancing and a low number of power components. The output voltage ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">v_o</i> ) gain is four times higher than the input voltage ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">v</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in</sub> ). Each mode of operation is discussed with a detailed current path. The conventional sinusoidal pulsewidth modulation technique is used to generate the gate pulses. Next, the experimental results are obtained from a 1 kW prototype setup. The proposed topology is tested under different scenarios such as load change, input voltage changes, and modulation variations. Both simulation and experimental results have good agreement in terms of efficiency. Finally, a detailed comparative study is performed with other recent 9L inverters to prove the merits of the proposed topology.

Implementation of SVM Based Multi-Level Inverter for Grid Connected PV System

Multilevel inverters are a novel type of dc–ac converter designed for medium and high voltage and power applications. Cascaded multilevel inverters are the most common inverters used in renewable energy applications. Despite the numerous advantages, the presence of extra circuit components in the design causes reliability concerns with these inverters. Researchers have faced a significant difficulty in constructing inverters with improved dependability by lowering total harmonic distortion (THD). This paper proposes a concept of Grid connected PV system with multilevel inverter topology. The PV system is implemented by using mathematical analysis and MPPT based dc-dc boost converter is used to improve the performance of PV system. In this paper, perturb and observe MPPT technique is implemented. For obtaining better harmonic distortions and proper synchronization with grid a multi-level inverter is implemented. This paper proposes a novel multilevel inverter topology for renewable energy operations which produces 31 and 51 level output voltages. The conventional topology is formed with 10 IGBT switches. A closed loop controller with sinusoidal pulse width modulation technique is implemented to generate gate signals required for 31-Level converter. The 51-Level converter is modelled with 8-IGBT switches and 4-diodes, also space vector and sinusoidal pulse width modulation techniques are used to generate the gate signals for switches. This proposed system is tested and verified in MATLAB and a comparative analysis made between sinusoidal and space vector modulation in 51-Level topology.

Rüzgâr Türbin Sisteminde İki ve Üç Seviyeli Dönüştürücü Tasarımı ve Güç Analizinin Yapılması

Günümüzde artarak devam enerji ihtiyacı ülkeleri yenilenebilir enerji kaynaklarından üretilen enerjilere yönlendirmiştir. Bu çalışmada, büyük güç gereksinimi duyulan rüzgâr türbinlerine uygun, çift beslemeli asenkron generatör (ÇBAG) tabanlı rüzgâr türbin sistemi incelenmiş ve benzetimi yapılmıştır. Bu türbin sistemi 6 adet 1,5 MW toplam 9MW gücünde 25 kV’luk dağıtım sistemine entegre, 30 km’lik bir hat uzunluğuna sahip, 25 kV’luk transformatör ile 120 kV’luk şebekeye güç üretmektedir. ÇBAG tabanlı rüzgâr türbin sistemi çift yönlü enerji akışına uygun olmasından dolayı arka arkaya bağlı iki adet dönüştürücüden oluşmaktadır. Matlab/ Simulink programında üç fazlı iki seviyeli dönüştürücü ve üç fazlı üç seviyeli dönüştürücünün tasarımı yapılmış ve sinüzoidal darbe genişlik modülasyon tekniği ile anahtarlama sinyalleri üretilmiştir. Bu dönüştürücüleri tasarladığımız ÇBAG tabanlı rüzgâr türbini modellemesinde kullanarak ve 15 m/sn rüzgar hızında toplam güç, reaktif güç ve sistemin çıkış gerilimleri değerleri kıyas edilmiştir. Benzetimi yapılan sistem için üç seviyeli dönüştürücü ile daha kararlı ve stabil sonuçlar alınmıştır.

Rapid Control Prototyping of Five-Level MMC based Induction Motor Drive with different Switching Frequencies

In this paper, Rapid Control Prototyping (RCP) of five-level Modular Multilevel Converter (MMC) based Induction Motor (IM) drive performance is observed with different switching frequencies. The Semikron based MMC Stacks with two half-bridge each are tested with the switching logic generated by phase and level shifted based Sinusoidal Pulse Width Modulation (SPWM) technique. The switching logic is generated by the Typhoon Hardware in Loop (HIL) 402. The disadvantages of Multilevel Converter like not so good output quality, less modularity, not scalable and high voltage and current rating demand for the power semiconductor switches can be overcome by using MMC. In this work, the IM drive is fed by MMC and the experimentally the performance is observed. The performance of the Induction Motor in terms of speed is observed with different switching frequencies of 2.5kHz, 5kHz, 7.5kHz, 10kHz, 12.5kHz and the results are tabulated in terms of Total Harmonic Distortion (THD) of input voltage and current to the Induction Motor Drive. The complete model is developed using Typhoon HIL 2021.2 Version Real-Time Simulation Software.

Multi-level inverter with novel carrier pulse width modulation technique for high voltage applications

&lt;span&gt;The present work deals with multilevel inverters (MLI) with modified carrier pulse width modulation technique and its application, especially in solar-based applications due to its modularity in structure and suitability for medium or high-power applications. Several multilevel inverters are introduced for various applications. One of the drawbacks of these inverters is high total harmonic distortion (THD) value in the output which impacts the power quality. The main objective of this work is to improve the power quality, thereby increasing the life and performance of the overall system at the consumer side. The most popular and compact cascaded multilevel DC-link inverter (CMDCLI) is considered for study and employed for 11-level operation. In general, sinusoidal pulse width modulation (SPWM) technique is used for control of inverter. However, the present work proposes a modified carrier-based hybrid pulse width modulation (HPWM) technique and has been tested with CMLDCLI. This novel technique compares the THD performance results with normal carrier wave considering R-L load. The results are analyzed in MATLAB environment and are validated with experimental results.&lt;/span&gt;