The increasing grid integration of wind power has led to the compulsory requirement of low-voltage ride through capability (LVRT) in wind turbines. Grid codes for LVRT capability of wind turbines are proposed in all major wind-energy-producing countries. The testing of LVRT capability compliance of the wind generators as per the specified grid codes during different fault conditions is essential to ensure its reliability. The testing process is generally done by the manufacturers and crucial for certification as per the IEC 61400-21 international standard for measurement of power quality characteristics of wind turbines. This review analyses the various testing tools under the software- and hardware-based categories. The review helps in understanding the present challenges in implementation of wind turbines, to alleviate the difficulty in LVRT testing procedures. © 2017, © 2017 Informa UK Limited, trading as Taylor &amp; Francis Group.

Palanisamy K

Department of Energy and Power Electronics

School of Electrical Engineering

Vellore Campus

Jerin A R.A

Subramaniam U.

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Testing of low-voltage ride through capability compliance of wind turbines – a review

International Journal of Ambient Energy

Fault-ride-through (FRT) is an imperative capability in wind turbines (WTs) to ensure grid security and transient stability. However, doubly fed induction generator-based WTs (DFIG-WTs) are susceptible to disturbances in grid voltage, and therefore require supplementary protection to ensure nominal operation. The recent amendments in grid code requirements to ensure FRT capability has compelled this study of various FRT solutions. Therefore, for improving FRT capability in pre-installed WTs, re-configuration using external retrofit-based solutions is more suitable and generally adapted. The most relevant external solutions based on retrofitting available are classified as (a) protection circuit and storage-based methods and (b) flexible alternating current transmission system-based reactive power injection methods. However, for new DFIG-WT installations, internal control modification of rotor-side converter (RSC) and grid-side converter (GSC) controls are generally preferred. The solutions based on modifications in RSC and GSC control of DFIG-WT are classified as (a) traditional control techniques and (b) advanced control techniques. This study ensures to curate and compare the FRT solutions available based on external retrofitting-based solutions and internal control modifications. Also, the future trends in FRT augmentation of DFIG-WTs are discussed in this study. © 2018 The Institution of Engineering and Technology.

Fulltext

IET Renewable Power Generation

Review on FRT solutions for improving transient stability in DFIG-WTs

This paper investigates the fault ride through (FRT) capability improvement of a doubly fed induction generator (DFIG)-based wind turbine using a dynamic voltage restorer (DVR). Series compensation of terminal voltage during fault conditions using DVR is carried out by injecting voltage at the point of common coupling to the grid voltage to maintain constant DFIG stator voltage. However, the control of the DVR is crucial in order to improve the FRT capability in the DFIG-based wind turbines. The combined feed-forward and feedback (CFFFB)-based voltage control of the DVR veries good transient and steadystate responses. The improvement in performance of the DVR using CFFFB control compared with the conventional feed-forward control is observed in terms of voltage sag mitigation capability, active and reactive power support without tripping, dc-link voltage balancing, and fault current control. The advantage of utilizing this combined control is veried through MATLAB/Simulink-based simulation results using a 1.5-MW grid connected DFIG-based wind turbine. The results showgood transient and steady-state response and good reactive power support during both balanced and unbalanced fault conditions. © 2017 IEEE.

IEEE Access

Improved Fault Ride Through Capability in DFIG Based Wind Turbines Using Dynamic Voltage Restorer With Combined Feed-Forward and Feed-Back Control

This paper proposes a single phase multilevel inverter configuration that conjoins three series connected full bridge inverter and a single half bridge inverter for renewable energy application especially photo-voltaic system. This configuration of multilevel inverter reduces the value of total harmonic distortion. The half bridge inverter utilized in the proposed configuration increases the output voltage level to nearly twice the output voltage level of a conventional cascaded H-bridge multilevel inverter. This higher output voltage level is generated with lesser number of power semiconductor switches compared to conventional configuration, thus reducing the total harmonic distortion and switching losses. The effectiveness of the proposed configuration is illustrated by replacing the isolated DC sources in multilevel inverter with individual photo-voltaic panels using separate perturb and observer based maximum power point tracking and boost converters. The verification of the proposed system is demonstrated successfully using MATLAB/Simulink based simulation with different irradiation and temperature conditions. Also, the transient operation of the system is verified with results depicted using step change in standard test condition. In the proposed system, total harmonic distortion of the output voltage is 9.85% without using passive filters and 3.91% with filter inductance. Theoretical calculation of the power losses and total harmonic distortion with mathematical equations are discussed. Selective experimental results are presented to prove the effectiveness of proposed system. © 2016 Elsevier Ltd

Energy Conversion and Management

Analysis and integration of multilevel inverter configuration with boost converters in a photovoltaic system

IEEE Transactions on Sustainable Energy

On-Site LVRT Testing Method for Full-Power Converter Wind Turbines

Wind Turbines - Design, Control and Applications

Standard Calculation of Fault Current Contribution of Doubly Fed Induction Generator-Based Wind Turbine

Renewable and Sustainable Energy Reviews

A comprehensive review of low voltage ride through capability strategies for the wind energy conversion systems

A comprehensive review of low-voltage-ride-through methods for fixed-speed wind power generators

Journal	International Journal of Ambient Energy
Publisher	Informa UK Limited
ISSN	0143-0750
Open Access	0