An Active Compensator to Counteract the Effects of Grid Impedance in Grid-Connected Inverter with an LCL Filter

This paper presents a design procedure for Proportional-Resonant (PR) controller and a third order LCL filter which decide the performance of the converter that is used to interface the renewable energy source to the grid. The primary focus of the paper is to evaluate the performance of the controller with the filter for a microgrid application. A scaled down model of microgrid available in the department laboratory is considered for the performance evaluation of the designed controller. The system is simulated with a 2kVA PWM inverter and tested under conditions such as change in grid impedance, grid frequency and step change in reference current. The simulation results show that the PR controller with LCL filter tracks the reference with zero steady state error and the controller is found to be immune to grid frequency and micro-grid configuration changes.

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An Integrated Design Approach for LCL-Type Inverter to Improve Its Adaptation in Weak Grid

Energies ◽

10.3390/en12132637 ◽

2019 ◽

Vol 12 (13) ◽

pp. 2637

Author(s):

Zheng ◽

Liu ◽

Li ◽

Dai ◽

...

Keyword(s):

Design Method ◽

Robustness Analysis ◽

Integrated Design ◽

System Stability ◽

Lcl Filter ◽

Weak Grid ◽

Grid Impedance ◽

Integrated Design Approach ◽

Simulation And Experiment ◽

Grid Connected Inverter

To improve the robustness of grid-connected inverter against grid impedance in a weak grid an integrated design method of LCL-filter parameters and controller parameters is proposed. In the method the inherent relation of LCL-filter parameters and controller parameters is taken into consideration to realize their optimized match. A parameter normalization scheme is also developed to facilitate the system stability and robustness analysis. Based on the method all normalization parameters can be designed succinctly according to the required stability and robustness. Additionally, the LCL parameter and controller parameter can be achieved immediately by restoring normalization parameters. The proposed design method can guarantee the inverter stability and robustness simultaneously without needing any compensation network, additional hardware, or the complicated iterative computations which cannot be avoided for the conventional inverter design method. Simulation and experiment results have validated the superiority of the proposed inverter design method.

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Resonance damping for an LCL filter type grid-connected inverter with active disturbance rejection control under grid impedance uncertainty

International Journal of Electrical Power & Energy Systems ◽

10.1016/j.ijepes.2019.02.004 ◽

2019 ◽

Vol 109 ◽

pp. 444-454 ◽

Cited By ~ 7

Author(s):

Muhammad Saleem ◽

Ki-Young Choi ◽

Rae-Young Kim

Keyword(s):

Disturbance Rejection ◽

Active Disturbance Rejection Control ◽

Lcl Filter ◽

Active Disturbance Rejection ◽

Disturbance Rejection Control ◽

Grid Impedance ◽

Filter Type ◽

Resonance Damping ◽

Grid Connected Inverter

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Robustness Investigation of Multi-Inverter-Paralleled Grid-Connected System with LCL-Filter Based on the Grid-Impedance Allocation Mechanism

IEEE Transactions on Power Electronics ◽

10.1109/tpel.2021.3088992 ◽

2021 ◽

pp. 1-1

Author(s):

Tianzhi Fang ◽

Shuheng Shen ◽

Yinglin Jin ◽

Xinbo Ruan

Keyword(s):

Allocation Mechanism ◽

Lcl Filter ◽

Grid Impedance

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Voltage Sensorless Model Predictive Control for a Grid-Connected Inverter with LCL Filter

IEEE Transactions on Industrial Electronics ◽

10.1109/tie.2021.3050395 ◽

2021 ◽

pp. 1-1

Author(s):

Nguyen Ngoc Ngoc Nam ◽

Ngoc-Duc Nguyen ◽

Changwoo Yoon ◽

Minho Choi ◽

Young Il Lee

Keyword(s):

Model Predictive Control ◽

Predictive Control ◽

Lcl Filter ◽

Grid Connected Inverter

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Modeling and Control of a Single-Phase Grid-Connected Inverter with LCL Filter

IEEE Latin America Transactions ◽

10.1109/tla.2021.9443067 ◽

2021 ◽

Vol 19 (02) ◽

pp. 250-259

Author(s):

Jakson Paulo Bonaldo ◽

Jose de Arimateia Olimpio Filho ◽

Augusto Matheus dos Santos Alonso ◽

Helmo Kelis Morales Paredes ◽

Fernando Pinhabel Marafao

Keyword(s):

Single Phase ◽

Lcl Filter ◽

Modeling And Control ◽

Grid Connected Inverter ◽

And Control

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A novel current controller design for grid-integrated PV inverter system

SN Applied Sciences ◽

10.1007/s42452-021-04290-4 ◽

2021 ◽

Vol 3 (3) ◽

Author(s):

Ayaz Ahmad ◽

L. Rajaji ◽

A. Iqbal

Keyword(s):

Controller Design ◽

Vital Role ◽

Current Feedback ◽

Lcl Filter ◽

Design Algorithm ◽

Grid Voltage ◽

Pv Inverter ◽

Current Controller ◽

Experimental Implementation ◽

Grid Connected Inverter

AbstractDistributed generators are playing a vital role in supporting the grid in ever-increasing energy demands. Grid code regulation must be followed when integrating the photovoltaic inverter system to the grid. The paper investigates and analyzes a controller model for grid-connected PV inverters to inject sinusoidal current to the grid with minimum distortion. To achieve better tracking and disturbance rejection, a DSP-based current controller is designed with LCL filter. The controller gets the current feedback from the grid, compares it with reference current, and calculates duty cycle to generate PWM pulses to trigger H-bridge converters. The grid voltage is loaded to the initial value in proposed PR controller to ensure the initial inverter voltage to match the grid voltage. The paper presents a novel current controller algorithm for grid-connected inverter system, and simulation is done. A detailed analysis has been carried out to validate the proposed design algorithm. Experimental implementation of the current controller in the DC/AC converter circuits with an LCL filter is done for 5.4 kW to validate and match the simulation model.

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