Diode Clamped Multilevel Inverter Research Articles

Solar Based Multilevel Inverter f o r BLDC Motor Drive

The BLDC motor is widely utilized in high power and low voltage applications because to its simple construction, great efficiency, low maintenance requirements, and low cost .Furthermore, considering their size, they have a lot of torque and power output. The BLDC motor is powered by an alternating current source and is operated straight from the AC supply port, despite being a DC motor in this case. The main drawback is that any disruptions in the source will have an impact on the applications that use BLDC motors in the industrial context. So, to avoid this, there should be a converter and an inverter intermediary between the motor and the source. One of three methods can be used to drive the BLDC motor. 1. Two-level inverters based on pulse width modulation (PWM). 2. An multiple-level working inverter. 3. A multilevel inverter with neutral clamping. Using a multicarrier PWM technique, the suggested inverter may lower the output signal's harmonic content. It is capable of generating very good motor currents. In this instance, a three-level diode clamped multilevel inverter can be used to accurately control the speed of a BLDC. This study's primary goal is to demonstrate how to run a BLDC drive with an inverter to lower harmonics. A diode clamped multi-level inverter is a device that converts voltage to current. An improved version of this strategy is provided by this research. Using the MATLAB Simulink software tool, one can assess the system's overall effectiveness by simulating the neutral clamp multilevel inverter-based drive system's functioning. In the event of a power outage, the entire application will cease to function and generate output. Under order to increase the output and supply reliability of power, renewable energies must be used under these circumstances. There are many renewable energy sources available; however solar photovoltaic systems are the better option because of their benefits over traditional power sources. A diode clamped multi-level inverter was used. A diode clamped multi-level inverter was used to drive the BLDC.

Formation of the Spectral Composition of the Output Voltage of Converters for Nuclear Magnetic Resonance

In this paper, we consider the construction of an asynchronous control system for semiconductor converters for nuclear magnetic resonance. The relevance of research in this direction, main problems that arise during the construction of these systems are shown. Derived the mathematical model of the inverter, on the basis of which a control system with asynchronous pulse-width modulation is constructed. Proposed an equivalent converter circuit with a constant structure, constant parameters, and an equivalent EMF generator. Established correspondence between the equivalent circuit of the converter and its mathematical model in the form of differential equations. On the basis of mathematical equations, a structural diagram of the converter with a control system was developed and the principle of operation of the device was described according to it. To develop an algorithm for the control system, the dependence of the frequency change relative to the resonant frequency on the phase shift between the current through the filter and the voltage on the antenna circuit is determined. For which the model was built in Simulink and the corresponding simulation was carried out. Numerical dependences of reference signal frequency change and phase shift were obtained. The increase in efficiency of device for nuclear magnetic resonance is considered due to the use of multilevel inverters with tuning the frequency of operation to the frequency of the resonant circuit. Simulation of a three-level diode-clamped inverter showed that when the capacitance of the resonant circuit changes and, therefore, the resonant frequency of the circuit, the input current increases. The work obtained specific numerical dependencies. Time diagrams of voltages and currents on the main elements of the converter are given, which illustrate the implementation asynchronous pulse-width modulation in the control system. After working out the automatic frequency control algorithm, the increase in current consumption can be leveled off. The simulation results also show that it is possible to reduce the amplitude of the third harmonic. The disadvantages of the proposed system include the fact that the frequency of the converter is adjusted at each subsequent period of its operation. At the same time, the parameters of the filter can change again, which leads us to believe that adjusting the frequency will never give a 100% result, but will only allow to get as close as possible to the set parameters of the sounding signal. The work also indicates that it is possible to improve the spectral composition of the probing voltage generated by the converter by using more levels of a diode-clamped multi-level inverter. However, increasing the number of levels reduces the action speed of the system and complicates the control system itself. Therefore, the need to maintain a balance between the number of levels of the inverter and the complexity of the system is indicated.

Performance analysis of FOC space vector modulation DCMLI driven PMSM drive

The effectiveness of a permanent magnet synchronous motor (PMSM) drive managed by an automatic voltage regulator (AVR) microcontroller using field oriented control (FOC) with space vector modulation (SVM) and a diode clamped multilevel inverter (DCMLI) is investigated. Due to its efficacy, FOC would be widely implemented for PMSM speed regulation. The primary drawbacks of a 3-phase classic bridge inverter appear to be reduced dv/dt stresses, lesser electromagnetic interference, and a relatively small rating, especially when compared to inverters. PMSMs have a better chance of being adopted in the automotive industry because of their compact size, high efficiency, and durability. The SVM idea states that an inverter's three driving signals are created simultaneously. Using MATLAB simulations, researchers looked into incorporating a DCMLI with a resistive load on an AVR microcontroller. Torque, current, and harmonic analysis were evaluated between the SVM and the inverter-driven PMSM drive in this research. In comparison to the prior art, the proposed PMSM drive has better speed and torque management, less output distortion, and less harmonic distortion.

Performance Analysis of Conventional IPMSM and NCPM Based IPMSM

This paper proposes a NCPM (Nano-composite coated permanent magnets)-based IPMSM (Interior Permanent Magnet Synchronous Motor) electric drive system, especially applicable for electric vehicles (EV). For an EV, an increase in the “T/A (torque per ampere)” condition is highly recommended, as it directly affects the maximum distance run by EV on a single charge. Due to NCPM, a substantial increase in magnetic flux intensity, resistance to corrosion and Curie temperature are observed. As a result, the proposed drive clearly exhibits a higher power to weight ratio. Also, it is capable of delivering higher T/A to the drive system without any considerable change in two important factors of EV: (1) mass and volume of the drive system (2) battery capacity of the drive system. Moreover, NCPM performance is less susceptible to temperature variation, which makes it an appropriate candidate for vehicular applications, where temperature inconsistency could be a common issue during working conditions. Also, NCPM-based IPMSM offers a quicker speed response than conventional IPMSM, thus providing higher acceleration, which is one of the important performance factors for vehicular applications. A vector controlled mathematical model of IPMSM and NCPM-based IPMSM is tested for various speed commands. Also, the NCPM-based IPMSM, in the proposed configuration, is fed from a three-level DCMLI (diode clamped multi-level inverter), as the drive system is considered for medium to high power applications. A comparative performance analysis is carried out between the proposed drive system and a conventional IPMSM-based drive system using MATLAB/SIMULINK to indicate the efficacy of the proposed configuration.

Comparison of Multilevel Inverters with T-type MLI: A Brief Review

This paper gives a comparative analysis of different types of Multilevel Inverters with T-Type inverters. The principal aim of the work is to analyse the T-type multilevel inverter operation with different multilevel inverters such as DiodeClamped Multilevel Inverter, Flying Capacitor Multilevel Inverter and Cascaded H-bridge Multilevel Inverter. All the inverters are compared and their advantages, disadvantages and usages are specified. The inverter used in our work runs on the multilayer bidirectional DC-DC converter. This can be used in Renewable Energy Sources and Electric Vehicle applications. The proposed design includes two power switches with an additional capacitor to balance the currents of the multilayer T-type (MLI) capacitor during an entire drive pattern or fault circumstances. In this design, the big capacitors being electrolytic in T-type Multilevel Inverter has been exchanged with longer-lasting film capacitors due to the highfrequency cycle-by-cycle current security between CN and CP. The converter’s dimensions and weight would be lowered by 20% because of this topology, as the number of switches and the capacitors used for balancing is reduced in this proposed design. The simulation analysis for five-level conventional T-type inverter and proposed T-type inverter with capacitor voltage balancing is done. The line-to-line voltages, line currents, phase voltages, three-phase voltages, and voltage total harmonic distortions are compared for conventional T-type inverter and proposed T-type inverter with capacitor voltage balancing. The simulation results shows that the proposed T-type inverter gives better performance compared to conventional T-type multilevel inverter.

Reduced Common Mode Multilevel Inverter Strategy in Photovoltaic Systems

Now-a-days, non-conventional energy sources are playing a vital role in the generation of electrical energy. This is due to the disadvantages in the conventional sources like pollution, non-availability of the resources, greenhouse effect. Hence more concentration is made by the researcher’s on these non-conventional sources so called as renewable energy sources. These renewable sources are used with the converters along with filters to give the best output. In this work, we are focusing on the renewable energy called solar energy and hence the converter is inverter in this case. Basically we have conventional inverters as well as multilevel inverters. Multilevel inverters are basically classified into three types and they are cascaded H-bridge multilevel inverter, diode clamped multilevel inverter, flying capacitor multilevel inverter. Among these cascaded multilevel inverter as many advantages like reduced number of components. This advantage is being used in this work and is simulated by using MATLAB.

Power quality improvement of microgrid fed electric ship using fuzzy controlled multi-pulse/multi-level converter-based VFD

This paper investigates a harmonic mitigation technique for modern electrical propulsion ships (EPS) microgrids (MG) using a fuzzy controlled multi-pulse rectifier (MPR) and multi-level inverter (MLI)-based variable frequency drive (VFD). In this paper, the proposed MPR-MLI-VFD system is studied using different-pulses rectifiers and different-level inverter-based VFD to achieve proper mitigation of the harmonics in the main generating power system of the ships within the marine classification society's limitations for harmonics. This is achieved using a proposed low harmonic multi-pulse rectifier based on zigzag transformers. Moreover, the voltage harmonic distortions at propulsion motor feeder buses are minimised using the proposed MLI. A simple fuzzy logic control system is proposed for the VFD speed control. The voltage balancing control system for the diode clamped multi-level inverters is implemented using a fuzzy control system. MATLAB/Simulink is used for the simulation and validation process.

An experimental realization of improved grid integrated multilevel inverter based PV systems with MPPT

AbstractThis research work explains a sliding mode controller‐based multilevel inverter for grid integrated photovoltaic power structure. A gravitational search algorithm based on maximum power point tracking has also been discussed for optimal photovoltaic power achievement. Moreover, a two‐stage cascaded interleaved boost converter has been employed, which provides minimised voltage/current ripple, higher current/power density, better efficacy, faster response, and reduced electromagnetic interference as major benefits. The multilevel inverter's proposed constant frequency‐based sliding mode controller provides better transient responses, high photovoltaic power tracking, and good robust behaviour under changing operating conditions. The proposed sliding mode controller has a fixed frequency operation and has low reactivity to parameter divergence. The proposed multilevel diode clamped inverter for grid integrated photovoltaic system provides a reduced number of components and a power rating. The gravitational search algorithm‐based swarm technique as a maximum power point tracking provides high convergence velocity, better accuracy, and good local search capability. The experimentation was carried out to implement control algorithms using the dSPACE platform. The designed multilevel inverter system with proposed control provides average 89.2% inverter efficiency under variation of sun insolations.

Dual Three Phase Multilevel Space Vector Modulation Control of Diode Clamped Inverter for Dual Star Induction Motor Drive

This work suggests a dual three-phase Space Vector Modulation (SVM) for the Diode Clamped Multilevel Inverter (DCMI) to ensure a robust control of Dual Star Induction Motor (DSIM). The principal scheme is investigated to apply the same control of the six-phase multilevel inverter by two three-phase multilevel inverter to drive the DSIM. The use of classic SVM control offers significant simplifications for controlling a six phase five levels inverter. The proposed control approach employs according to the hybridization of various conversion functions to establish the modulation strategy for each voltage vector and its placement in the plane of voltage modulation in distinctly and easy manner. A numerical simulation under MATLAB/Simulink is carried out to evaluate the Indirect Field Oriented Control (IFOC) of DSIM drive fed by multilevel inverters. The simulation outcomes clearly reveal good performance of the designed control strategy in terms of THD and control efficiency.

Hybrid Multi-Level Source Inverter Design and Validation in Solar Photo-voltaic Renewable Energy System

This paper proposes the hybrid multi-level source inverter in light of staggered coordinated framework for boosting photo voltaic power. Hybrid multi-level inverter (MLI) proposed to design less number of switches compare with other MLIs of diode clamped multi-level inverter, the smallest number of switches are required to accomplish the highest steps in staircase AC output voltage. HMLIs additionally include variable info voltage and carries out load guideline to keep up with consistent result voltage. The HMLIS intends to operate in multiple stages during shoot through stage exchanging beat width (PWM) adjustment keeps up with to work in buck and lift mode. The activity of proposed work implemented in MATLAB and discuss effectiveness with diminished sounds took care of inverter operation. Model of converter is planned and accomplished the most extreme effectiveness of 95.4% as information voltage goes from 10-60 volts and result of half breed staggered source inverter keeps up with steady of 230v dc. Trial results approve the exhibition of proposed half and half staggered source inverter for exchanged mode power supplies utilized in PC.

Multi-phase inverter-controlled induction machine at varied rotor parameters

<p>This paper presents a step-wise modelling of a symmetrical six-phase induction machine driven by a six-phase diode clamped multi-level inverter at a varying rotor resistance and motor inertia. The machine drive process was considered in two stages. The first stage presents the dynamic behavior of the machine when a load torque of 0 Nm and 100 Nm is applied at a varied rotor external resistance value of (0.8 and 3.2) Ω with constant motor inertia. The second stage showcased the variations in the speed, electromagnetic torque and rotor current when motor inertia is varied at (0.5 and 1.5) Kg-m2 with rotor resistance held constant. A six-phase five-level diode clamped converter phase displaced by sixty degrees with a modulation index of 0.8 was modeled to drive the poly-phase machine at a reduced %THD. All machine models were simulated in MATLAB 7.11. The simulation results showed that reduced oscillations in rotor current, motor speed and torque pulsations were achieved at a varied external rotor resistance and motor inertia.</p>

Performance analysis of capacitor voltage balancing in modular multilevel converter by sorting algorithm

<span lang="EN-US">Due to the modularity of modular multilevel converter (MMC), therefore it has been considered as a substitute for the diode-clamp multilevel inverter in applications of high-voltage high-power. Where it can obtain any level of voltage without imposing complexity on the control system. This study analyses in detail the operation principle and balances the capacitor voltage of sub-module (SM) in modular multilevel converter by sorting algorithm. The output voltage control and capacitor voltage balancing technique are confirmed by MATLAB/Simulink and the obtained result has been discussed, where the capacitor voltage of the sub-module has controlled within the acceptable deviation limit, which is 5-10%. In addition, the circulating current has been controlled and reduced.</span>

Performance enhancement of DCMLI fed DTC-PMSM drive in electric vehicle

This paper focus on the simulation and hardware analysis of a diode clamped multilevel inverter (DCMLI) fed direct torque control (DTC) permanent magnet synchronous motor (PMSM) drive in electric vehicle (EV) application. DTC-PMSM drive is more used for torque and speed control. The existing DTC PMSM drive consists of torque and flux hysteresis comparators and suffers from variable switching frequency and torque ripples. These problems can be solved by using carrier-based space vector modulation (CBSVM) about torque and flux. In this proposed approach a DCMLI fed 4 poles, 0.5 HP DTC PMSM drive system is designed and simulated using carrier-based CBSVM. Simulation and experimental implementation are carried out in MATLAB environment and AVR Microcontroller respectively. The simulated performances are studied in steady-state and transient conditions for varying load, speed, and torque. The results of the DTC-PMSM drive system using CBSVM show that the proposed method can effectively reduce the torque ripple and maintain a constant speed and also improved driving performance of drive for electric vehicle applications.

A Nonlinear Controller for Neutral Point Piloted (T-Type) Multilevel Inverter-Based Three-Phase Four-Wire DSTATCOM

In recent times, neutral point piloted (NPP) or half-leg T-type multilevel inverter (MLI) becomes a promising topology for medium-voltage high-power applications. This T-type MLI is the best substitute for diode clamped multilevel inverter (DCMLI) due to its simple structure and absence of clamping diodes. However, the neutral point voltage control or dc bus capacitors' balance of NPP T-type MLI is a challenging task. Therefore, this paper presents a nonlinear sliding mode controller (SMC) for dc-link voltage balance and reference current control in distribution static compensator (DSTATCOM). For this, a three-level T-type MLI-based three-phase four-wire DSTATCOM is considered to eliminate current-related power quality issues such as harmonics, reactive power, load unbalance, and neutral current. The proposed NPP T-type-based DSTATCOM is compared with DCMLI and active DCMLI-based DSTATCOMs in terms of switching losses and cost. Simulation studies are carried out in MATLAB Simulink environment and further corroborated with experimental studies. Furthermore, the ability of the proposed SMC-based controller is compared with the PI controller under different operating conditions.

Switching Sequence Control 31-Level Asymmetric Cascaded of Reduced Switch Count Multilevel Inverter with Multi Carrier Pulse Width Modulation

Various pulse width modulation techniques, including as cascaded multilevel inverters (MLI), diode clamped multilevel inverters, and flying capacitor multilevel inverters, can be used to simply operate common inverters. Due to increased switching losses, current MLIs cannot reach high efficiency. Due to lower losses and THD than standard MLI topologies, the asymmetric cascaded multi-level H-bridge inverter architecture examined in this white paper employs fewer switches and more output voltage levels (Total Harmonic Distortion). The THD is less than the IEEE standard because of the suggested architecture. In this instance, phase difference (PD) multi-carrier PWM techniques are used to control the gate pulses using sinusoidal reference. Each switch receives a different pulse pattern thanks to a method of decimal-to-binary conversion. It is possible to utilise the suggested circuit for applications requiring moderate to high power, and it is quite simple to evaluate. Utilize the MATLAB/SIMULINK environment to simulate time-domain behaviour for the 31-level and 33-level multilevel inverter topologies.

Novel multi-device unified powerquality conditioner for powerquality improvement

This paper describes the customizable multi-device unified power-quality conditioner (MD-UPQC) is designed especially for multi-feeder distribution networks. The proposed MD-UPQC can exchange the power between the multi-feeders and proficiently mitigates all voltage-current associated power-quality problems, make sure to maintain balanced power-flow to consumers. At recent days, various manufacturers recommend the provision of multilevel inverters in mid-range customized compensation devices with desirable control schemes. In distinct, the 5-level diode-clamped multi-level inverter (DCMLI) is best suited for MD-UPQC over traditional 3-level voltage source inverter (VSI) topology for attaining enhanced features. In this paper, MD-UPQC has been proposed with three 5-level DCMLI modules interfaced as back-to-back with a common direct current (DC) capacitor. The simplified phase-dispositional modulation technique is easily assembled with proposed universal voltage-current reference controller for significant functioning of DCMLI-MDUPQC device. The operation and performance of proposed model and its control scheme is evaluated with MATLAB/Simulink computational tool, simulation results are presented.

Power enhancement of transformer less single-phase grid connected solar-wind energy conversion system for various environmental conditions

Abstract This article presents the grid connected hybrid solar-wind energy conversion system (HSWECS) using the cascaded diode clamped multilevel inverter (CDCMLI). The advantage of CDCMLI over the conventional cascaded H-bridge multilevel inverter (CHBMLI) is that the power transfer capacity of the CDCMLI is doubled. The solar and wind energy conversion systems are connected individually to the DC-links of CDCMLI through the DC–DC converter which is used to get maximum power from solar and wind systems. Due to the fluctuating power supply by renewable sources, the isolated DC-links of separate inverters suffer from varying DC-link voltages. A control scheme is proposed which is capable of balancing these DC-link voltages under various power generation scenarios, extracting the maximum possible power from renewable energy sources (RES), and injecting it into the grid at near unity power factor. The proposed control also monitors the power quality of the injected current into the grid. Furthermore, it allows the system to be connected to the grid without any transformer. In addition, mathematical modeling of the CDCMLI has been presented. The performance of the system is analyzed with Matlab/Simulink and confirmed by a prototype model with dSpace 1104.

An Improved Conventional Diode-Clamped Multilevel Inverter Using Non-Zero Triangular- Based Unipolar Modulation Scheme

This paper presents an improved conventional diode-clamped multilevel inverter using non-zero triangular-based unipolar modulation scheme. The proposed scheme is meant to reduce the number of carrier waves, minimize the circuits of modulation scheme and obtain stabilized output voltage waveforms. Non-zero triangular-based unipolar modulation scheme is actualized by using two zero-free triangular wave carriers and two modulating sinewaves for line-to- line five level output voltage waveforms in single phase full bridge diode-clamped multilevel inverter unlike conventional multicarrier sinusoidal pulse width modulation that uses four triangular waves and one modulating sinewave for the same inverter type. The proposed system also used microcontroller in the combinational of its wave signals in order to generate the appropriate triggering signals for switching the power semiconductor switches. The proposed system has the following features: (i) It produces two distinct triggering trains (W1 and W2) meant to reduce the low and high harmonics unlike conventional modulation techniques (ii) All its carrier waves operate in continuous current mode which makes it unique from other multicarrier and other related modulation schemes (iii) it has low component counts. The proposed scheme on the conventional diode-clamped inverter produced the following results: voltage and current with total harmonic distortions of 0.4547%, stabilized 400V output voltage and 20A output current, probability results at each level of voltage and current occurrences are 0.10, 0.25, 0.25, 0.75 and 0.90; power output of 80kW, low component counts of modulation circuit scheme and experimental prototype.

Solar Photovoltaic System-Based Reduced Switch Multilevel Inverter for Improved Power Quality

This paper deals with a reduced switch multi-level inverter for the solar photovoltaic system-based 127-level multi-level inverter. The proposed technique uses the minimum number of switches to achieve the maximum steps in staircase AC output voltage when compared to the flying capacitor multi-level inverter, cascaded type multilevel inverter and diode clamped multi-level inverter. The use of a minimum number of switches decreases the cost of the system. To eliminate the switching losses, in this topology a square wave switch is used instead of pulse width modulation. Thereby the total harmonic distortion (THD) and harmonics have been reduced in the pulsating AC output voltage waveform. The performance of 127-level MLI is compared with 15 level, 31-level and 63-level multilevel inverters. The outcomes of the solar photovoltaic system-based 127-level multi-level inverter have been simulated in a MATLAB R2009b environment.

Switching Sequence Control 31-Level Asymmetric Cascaded of Reduced Switch Count Multilevel Inverter with Multi Carrier Pulse Width Modulation

Various pulse width modulation techniques, including as cascaded multilevel inverters (MLI), diode clamped multilevel inverters, and flying capacitor multilevel inverters, can be used to simply operate common inverters. Due to increased switching losses, current MLIs cannot reach high efficiency. Due to lower losses and THD than standard MLI topologies, the asymmetric cascaded multi-level H-bridge inverter architecture examined in this white paper employs fewer switches and more output voltage levels (Total Harmonic Distortion). The THD is less than the IEEE standard because of the suggested architecture. In this instance, phase difference (PD) multi-carrier PWM techniques are used to control the gate pulses using sinusoidal reference. Each switch receives a different pulse pattern thanks to a method of decimal-to-binary conversion. It is possible to utilise the suggested circuit for applications requiring moderate to high power, and it is quite simple to evaluate. Utilize the MATLAB/SIMULINK environment to simulate time-domain behaviour for the 31-level and 33-level multilevel inverter topologies.