{"title":"THD Analysis of Cascaded H-Bridge Inverter with Fuzzy Logic Controller","authors":"N. Sivakumar, A. Sumathi","doi":"10.4236/CS.2017.87011","DOIUrl":null,"url":null,"abstract":"In recent days, the multilevel inverter technology is widely applied to domestic \nand industrial applications for medium voltage conversion. But, the power \nquality issues of the multilevel inverter limit the usage of much sensitive \nequipment like medical instruments. The lower distortion level of the output \nvoltage and current can generate a quality sinusoidal output voltage in inverters \nand they can be used for many applications. The harmonics can cause \nmajor problems in equipments due to the nonlinear loads connected with the \npower system. So, it is necessary to minimize the losses to raise its overall efficiency. \nIn this paper, a new topology of seven level asymmetrical cascaded \nH-bridge multilevel inverter with a Fuzzy logic controller had been implemented \nto reduce the Total Harmonic Distortion (THD) and to improve the \noverall performance of the inverter. The proposed model is well suited for use \nwith a solar PV application. In this topology, only six IGBT switches are used \nwith three different voltage ratings of PV modules (1:2:4). The lower number \nof semiconductor switches leads to minimizing overall di/dt ratings and voltage \nstress on each switches and switching losses. The gate pulses generated by \nSinusoidal Pulse Width Modulation (SPWM) technique with a Fuzzy logic \ncontroller are also introduced. A buck-boost converter is used to maintain the \nconstant PV voltage level integrated by an MPPT technique followed by Perturb \nand Observer algorithm is also implemented. The MPPT is used to harness \nthe maximum power of solar radiations under its various climatic conditions. \nThe new topology is evaluated by a Matlab/Simulink model and compared \nwith a hardware model. The results proved that the THD achieved by \nthis topology is 1.66% and realized that it meets the IEEE harmonic standards.","PeriodicalId":63422,"journal":{"name":"电路与系统(英文)","volume":"08 1","pages":"171-183"},"PeriodicalIF":0.0000,"publicationDate":"2017-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"电路与系统(英文)","FirstCategoryId":"1093","ListUrlMain":"https://doi.org/10.4236/CS.2017.87011","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 1
Abstract
In recent days, the multilevel inverter technology is widely applied to domestic
and industrial applications for medium voltage conversion. But, the power
quality issues of the multilevel inverter limit the usage of much sensitive
equipment like medical instruments. The lower distortion level of the output
voltage and current can generate a quality sinusoidal output voltage in inverters
and they can be used for many applications. The harmonics can cause
major problems in equipments due to the nonlinear loads connected with the
power system. So, it is necessary to minimize the losses to raise its overall efficiency.
In this paper, a new topology of seven level asymmetrical cascaded
H-bridge multilevel inverter with a Fuzzy logic controller had been implemented
to reduce the Total Harmonic Distortion (THD) and to improve the
overall performance of the inverter. The proposed model is well suited for use
with a solar PV application. In this topology, only six IGBT switches are used
with three different voltage ratings of PV modules (1:2:4). The lower number
of semiconductor switches leads to minimizing overall di/dt ratings and voltage
stress on each switches and switching losses. The gate pulses generated by
Sinusoidal Pulse Width Modulation (SPWM) technique with a Fuzzy logic
controller are also introduced. A buck-boost converter is used to maintain the
constant PV voltage level integrated by an MPPT technique followed by Perturb
and Observer algorithm is also implemented. The MPPT is used to harness
the maximum power of solar radiations under its various climatic conditions.
The new topology is evaluated by a Matlab/Simulink model and compared
with a hardware model. The results proved that the THD achieved by
this topology is 1.66% and realized that it meets the IEEE harmonic standards.