Design of lcl filter for photovoltaic grid-connected inverter

How a LCL filter is used to connect an inverter to the grid?

A LCL filter is often used to interconnect an inverter to the utility grid in order to filter the harmonics produced by the inverter. This paper deal design methodology of a LCL filter topology to connect à inverter to the grid, an application of filter design is reported with m-file in Matlab.

What is a L filter in a grid-connected inverter?

An L filter or LCL filter is usually placed between the inverter and the grid to attenuate the switching frequency harmonics produced by the grid-connected inverter. Compared with L filter, LCL filter has better attenuation capacity of high-order harmonics and better dynamic characteristic [2, 3].

What is a power converter & LCL filter?

The use of power converters is very important in maximizing the power transfer from renewable energy sources such as wind, solar, or even a hydrogen-based fuel cell to the utility grid. An LCL filter is often used to interconnect an inverter to the utility grid in order to filter the harmonics produced by the inverter.

Why are LCL filters used in grid-connected inverters and PWM active rectifiers?

LCL filters have been used in grid-connected inverters and pulse width-modulated (PWM) active rectifiers because they minimize the amount of current distortion injected into the utility grid Good performance can be obtained in the range of power levels up to hundreds of kilowatts, with the use of small values of inductors and capacitors. Fig.3.

Do LCL filters affect the stability margins of grid-connected inverters?

LCL filters are applied to reduce the total harmonic distortion of grid-injected current by inverters. The stability margins of the LCL-filtered grid-connected inverter will be affected by the resonance frequency of LCL filters. This paper design optimal active damping of capacitor current feedback and optimal proportional resonant controller.

Why is a LCL filter used in a transformerless inverter?

Thus, an LCL filter is normally installed at the inverter output to efficiently reduce the current harmonics. Among different PWM switching schemes, double-frequency unipolar PWM has drawn little attention due to the issue of common-mode leakage current in transformerless inverters.