Wind energy conversion system using perturb&observe-based maximum power point approach interfaced with T-type three-level inverter connected to grid

In this paper,the performance of a permanent magnet synchronous generator(PMSG)-based wind energy conversion system(WECS)supplied to an uncontrolled rectifier-fed boost converter(BC)interfaced with a three-phase T-type three-level inverter(TLI)has been analysed.The proposed WECS involves three converters,namely an uncontrolled rectifier that is used for conversion from AC to DC;a BC supplied by a PMSG-fed rectifier used to enhance the voltage gain;and a grid-connected three-phase T-type TLI is proposed to eliminate power-quality issues with synchronization of grid voltage and current.The main goal of this research is to model and control the grid-connected T-type TLI using a d-q synchronous frame for wind energy for regulating the DC-link voltage and transferring the generated wind power from the BC to the grid.Furthermore,the perturb&observe(P&O)-based maximum power point(MPP)approach is recommended to keep track of the MPP for a BC that is supplied from a PMSG-based WECS under constant and variable wind speeds.The proposed PMSG-based WECS interfaced with grid-connected T-type TLI using d-q control has been computationally modelled,simulated and validated with constant and variable speeds using MATLAB®and Simulink®.It is confirmed that the P&O-based MPP approach ensures maximum power for varying wind speeds,and the total harmonic distortion of the T-type TLI grid current value is 3.18%,which is within IEEE-519 limits.Furthermore,with grid synchronization,the power factor of the T-type TLI is maintained at unity to avoid power-quality issues.

Evaluation of On-Line MPPT Algorithms for PV-Based Battery Storage Systems

This paper presents a novel Simulink models with an evaluation study of more widely used On-Line Maximum Power Point tracking(MPPT)techniques for Photo-Voltaic based Battery Storage Systems(PV-BSS).To have a full comparative study in terms of the dynamic response,battery state of charge(SOC),and oscillations around the Maximum Power Point(MPP)of the PV-BSS to variations in climate conditions,these techniques are simulated in Matlab/Simulink.The introduced methodologies are classified into two types;the first type is conventional hill-climbing techniques which are based on instantaneous PV data measurements such as Perturb&Observe and Incremental Conductance techniques.The second type is a novel proposed methodology is based on using solar irradiance and cell temperature measurements with pre-build Adaptive Neuro-Fuzzy Inference System(ANFIS)model to predict DC–DC converter optimum duty cycle to track MPP.Then evaluation study is introduced for conventional and proposed On-Line MPPT techniques.This comparative study can be useful in specifying the appropriateness of the MPPT techniques for PV-BSS.Also the introduced model can be used as a valued reference model for future research related to Soft Computing(SC)MPPT techniques.A significant improvement of SOC is achieved by the proposed model and methodology with high accuracy and lower oscillations.

Interleaved high-gain boost converter powered by solar energy using hybrid-based MPP tracking technique

This paper presents a solar-powered interleaved high-gain boost converter(IHGBC)that increases voltage gain with fewer ripples in the output voltage in comparison to existing DC-DC converters.The goal of this research is to develop a hybrid-based maximum power point tracking(MPPT)approach with the combination of a flower pollination(FP)algorithm assisted with a perturb&observe(P&O)MPPT approach for solar photovoltaic(SPV)systems integrated with IHGBC.To ensure effective usage of both FP and P&O algorithms,this study incorporates and validates the hybrid-based MPPT approach.The proposed solar-powered IHGBC with a hybrid-based MPPT algorithm has been computationally modelled and simulated using MATLAB®and Simulink®for both uniform and non-uniform irradiation and analysed for voltage gain,ripples in the output waveforms and convergence time.The proposed hybrid-based MPPT is based on a number of flowers that forecast the initial global peak,assisted by P&O in the last stage for faster convergence to attain the maximum power point(MPP).As a result,the hybrid-based MPPT approach alleviates the computational issues encountered in P&O and FP-based MPP approaches.The proposed hybrid MPPT is compared with conventional MPPT for SPV and the results show that the solar-powered IHGBC using a hybrid-based MPPT technique has negligible oscillations of 0.14%with a high-voltage gain of 7.992 and a fast convergence rate of 0.05 seconds compared to individual P&O-based MPPT and FP-based MPPT techniques.The simulation results of the proposed MPPT with IHGBC outperform the conventional MPPT with high-gain converters.