A new eight switch seven level boost active neutral point clamped (8S-7L-BaNPC) inverter

A new boost Active-Neutral-Clamped (ANPC) voltage boosting inverters are appealing for low dc-link voltage demand. Recent boost ANPC topology has demonstrated a 1.5 times voltage gain, but the number of switches has a higher number. This paper proposed an improved boost ANPC topology with 1.5 voltage gain using the least number of switches. Further, the number of conducting switches has been reduced remarkably which enhances the system efficiency. The seven-level (7L) output voltage levels are achieved using a floating capacitor with self-voltage balancing capability. The proposed topology has been analyzed and compared to the ANPC topologies proposed in recent years. For the validation of the theoretical aspect of the proposed topology, the experimental findings have been compiled in the paper.This work was supported by the Qatar University-Marubeni Concept to Prototype Development Research grant # [MCTP-CENG-2020-2] from the Qatar University and the publication charges is paid by the Qatar National Library, Doha, Qatar.Scopu

A new boost switched capacitor seven-level grid-tied inverter

In this paper, a new switched capacitor-based multilevel inverter structure is suggested. The proposed topology can generate seven-level output voltage waveform using ten power electronic switches and two floating capacitors. This structure has the ability to boost the input DC voltage, up to 1.5 times. Although this topology can generate an output waveform with large number of levels, it does not increase the voltage stress on the power electronic switches. There is no need for capacitor voltage balancing in this structure since the capacitors are balanced through charging and discharging modes of operation. In addition, the suggested switched capacitor inverter reduces the number of input dc power supplies and uses a single dc source such as a photovoltaic (PV) panel. Since the proposed inverter is an neutral point clamp based multilevel inverter topology, the leakage current is minimized and as a result the overall efficiency of the proposed system is increased. The operation modes and steady-state analysis of the proposed structure are explained in detail. In order to validate the feasibility of the proposed topology, some experimental results are presented in the grid connected mode of operation

Performance analysis and control of a novel 7-level active neutral point clamped (ANPC) topology

This paper introduces a novel 7-level active neutral-point clamped (ANPC) switched capacitor multilevel inverter (SCMLI) with voltage-boosting capabilities. The proposed converter can produce seven levels and a voltage boosting of 1.5 times with a single dc source. For boosting the voltage, two self-balanced switched capacitors and two dc link capacitors with active neutral point are used with nine switches. For controlling the output voltage, the level-shifted modulation technique and modified nearest level control technique is used. The performance of the converter is evaluated with both modulation techniques. The operation of the proposed SCMLI and the design of capacitors for the proposed circuit is discussed in detail. The proposed topology can eliminate the leakage current and has reduced voltage stress across switches which makes it suitable for solar photovoltaic applications. The proposed converter is compared with some other recently introduced converters in terms of voltage gain, the number of components used, and the voltage stress across the switches. For verifying the performance of the proposed circuit, the experimental and simulation results are presented in the paper. The experimental results closely agree with the simulation and theoretical studies. The total harmonic distortion (THD) in the output voltage and efficiency is compared with both modulation techniques. 2023 The Authors. IET Power Electronics published by John Wiley & Sons Ltd on behalf of The Institution of Engineering and Technology.Scopu

A New Step-Up Switched-Capacitor Voltage Balancing Converter for NPC Multilevel Inverter-Based Solar PV System

This paper proposed a grid connected solar Photovoltaic (PV) Systems with a new voltage balancing converter suitable for Neutral-Point-Clamped (NPC) Multilevel Inverter (MLI). The switched-capacitors used in the proposed converter is able to balance the DC link capacitor voltage effectively by using proper switching states. The proposed balancing converter can be extended to any higher levels and it can boost the DC input voltage to a higher voltage levels without using any magnetic components. This feature allows the converter to operate with the boosting capability of the input voltage to the desired output voltage while ensuring the self-balancing. In this paper the proposed converter is used for a grid connected solar PV system with NPC multilevel inverter, which is controlled using vector control scheme. The proposed grid connected solar PV system with associated controllers and maximum power point tracking (MPPT) is implemented in Matlab/SimPowerSystem and experimentally validated using dSPACE system and designed converters. The simulation and experimental results show that the proposed topology can effectively balance the DC link voltage, extract maximum power from PV module and inject power to the grid under varying solar irradiances with very good steady state and dynamic performances

7L-SCBI topology with minimal semiconductor device count

In this work, a seven-level switched capacitor boost inverter (7L-SCBI) is proposed with minimal resource count. The proposed inverter requires only eight switches and two capacitors to generate a seven-level voltage. The proposed 7L-SCBI is capable of generating a multilevel voltage as well as boost the input DC-link voltage up to 1.5 times with a reduced blocking voltage of switches and capacitors. The comparison in terms of efficiency and device count with other switched capacitor topologies is presented in detail. The performance validation of the proposed 7L-SCBI is done with the help of a laboratory prototype. reserved.This publication was made possible by Qatar University-Marubeni Concept to Prototype Development Research grant # [M-CTP-CENG-2020-2] from the Qatar University. The statements made herein are solely the responsibility of the authors.Scopu

New Topologies and Advanced Control of Power Electronic Converters for Renewable Energy based Microgrids

Solar energy-based microgrids are increasingly promising due to their many features, such as being environmentally friendly and having low operating costs. Power electronic converters, filters, and transformers are the key components to integrate the solar photovoltaic (PV) systems with the microgrids. The power electronic converters play an important role to reduce the size of the filter circuit and eliminate the use of the bulky and heavy traditional power frequency step-up transformer. These power converters also play a vital role to integrate the energy storage systems such as batteries and the superconducting magnetic energy storage (SMES) unit in a solar PV power-based microgrid. However, the performance of these power converters depends upon the switching technique and the power converter configuration. The switching techniques can improve the power quality, i.e. lower total harmonic distortion at the converter output waveform, reduce the converter power loss, and can effectively utilize the dc bus voltage, which helps to improve the power conversion efficiency of the power electronic converter. The power converter configuration can reduce the size of the power converter and make the power conversion system more efficient. In addition to the advanced switching technique, a supervisory control can also be integrated with these power converters to ensure the optimal power flow within the microgrid. First, this thesis reviews different existing power converter topologies with their switching techniques and control strategies for the grid integration of solar PV systems. To eliminate the use of the bulky and heavy line frequency step-up transformer to integrate solar PV systems to medium voltage grids, the high frequency magnetic linkbased medium voltage power converter topologies are discussed and compared based on their performance parameters. Moreover, switching and conduction losses are calculated to compare the performance of the switching techniques for the magnetic-linked power converter topologies. In this thesis, a new pulse width modulation technique has been proposed to integrate the SMES system with the solar PV system-based microgrid. The pulse width modulation technique is designed to provide reactive power into the network in an effective way. The modulation technique ensures lower total harmonic distortion (THD), lower switching loss, and better utilization of dc-bus voltage. The simulation and experimental results show the effectiveness of the proposed pulse width modulation technique. In this thesis, an improved version of the previously proposed switching technique has been designed for a transformer-less PV inverter. The improved switching technique can ensure effective active power flow into the network. A new switching scheme has been proposed for reactive power control to avoid unnecessary switching faced by the traditional switching technique in a transformer-less PV inverter. The proposed switching technique is based on the peak point value of the grid current and ensures lower switching loss compared to other switching techniques. In this thesis, a new magnetic-linked multilevel inverter has been designed to overcome the issues faced by the two-level inverters and traditional multilevel inverters. The proposed multilevel inverter utilizes the same number of electronic switches but fewer capacitors compared to the traditional multilevel inverters. The proposed multilevel inverter solves the capacitor voltage balancing and utilizes 25% more of the dc bus voltage compared to the traditional multilevel inverter, which reduces the power rating of the dc power source components and also extends the input voltage operating range of the inverter. An improved version magnetic-linked multilevel inverter is proposed in this thesis with a model predictive control technique. This multilevel inverter reduces both the number of switches and capacitors compared to the traditional multilevel inverter. This multilevel inverter also solves the capacitor voltage balancing issue and utilizes 50% more of the dc bus voltage compared to the traditional multilevel inverter. Finally, an energy management system has been designed for the developed power converter and control to achieve energy resiliency and minimum operating cost of the microgrid. The model predictive control-based energy management system utilizes the predicted load data, PV insolation data from web service, electricity price data, and battery state of charge data to select the battery charging and discharging pattern over the day. This model predictive control-based supervisory control with the advanced power electronic converter and control makes the PV energy-based microgrid more efficient and reliable

Four-Level Three-Phase Inverter With Reduced Component Count for Low and Medium Voltage Applications

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