The Brushless Doubly Fed Induction Generator (BDFIG) has huge potential for wind power systems due to its high reliability and low maintenance cost. To add inertia for system stability enhancement, as well as to maintain the uninterrupted operation during symmetrical grid faults, this study proposes a Virtual Synchronous Control (VSC) with a transient current compensation strategy for BDFIG. The proposed VSC is realized by regulating the virtual inner electrical potential and angular velocity of BDFIG under Control Winding (CW) current oriented vector control, and compensating for the transient CW current to weaken the transient inner electrical potential under symmetrical grid faults. Modeling and analysis of such a VSC strategy are presented in this paper, and a simulation is also made to compare the performances of existing and proposed VSC strategies. It is shown that the merits of the proposed VSC can enhance the fault ride through the ability of the BDFIG system and support the recovery of grid voltage.

https://www.mdpi.com/1996-1073/12/2/319/pdf

Virtual Synchronous Control Based on Control Winding Orientation for Brushless Doubly Fed Induction Generator (BDFIG) Wind Turbines Under Symmetrical Grid Faults

The brushless doubly fed machine (BDFM) drive system based on a fractional unidirectional converter is a promising low-cost variable-speed drive system, which shows great potential in applications of driving fans and pumps. However, the harmonic current generated by a diode rectifier can flow into the machine and the grid under a weak grid, which will cause a 6th-order frequency torque ripple and lead to voltage distortion. A steady equivalent circuit considering the uncontrolled rectifier and the grid impedance is built firstly to study the harmonic distribution characteristics. To eliminate the influence of harmonic currents, the harmonic equivalent impedance of the machine system should be regulated to change the harmonic distribution characteristics. This paper improves the conventional control method through adding a harmonic control loop to prevent harmonic currents from being injected into the machine or the grid, which is then applied in the fundamental synchronous frame. Two indirect parameters are selected to realize the two control targets. Afterwards, the influence of the control system on the harmonic equivalent impedance of the machine system under the conventional method and the proposed method are compared. Finally, experimental results obtained from a 30 kW BDFM prototype verify the proposed method.

/pdf/bidirectional-harmonic-current-control-of-brushless-doubly-4k25sumjbh.pdf

Bidirectional Harmonic Current Control of Brushless Doubly Fed Motor Drive System Based on a Fractional Unidirectional Converter Under a Weak Grid

Grid codes require wind turbines to have capability to withstand a certain grid voltage unbalance without tripping. However, existing controls for brushless doubly-fed induction generator (BDFIG) based wind turbine under grid unbalance have many problems such as difficulty in realizing decoupling control, involvement with flux or current estimations, and complex control structure. Moreover, the existing studies only focused on the control of machine side converter (MSC), but the coordinated control between MSC and grid side converter (GSC) and the control objectives of overall BDFIG wind turbine system have not yet been addressed so far. To overcome these problems and improve the control capability, this paper proposes a coordinated control strategy by considering MSC and GSC together. First, the enhanced control objectives for overall BDFIG wind turbine system are determined. Second, the simple single current closed-loop controllers without involving with any flux or current estimations are designed for MSC and GSC, respectively. Meanwhile, in current loops, all the disturbances and cross-coupling terms on dq axes are derived and used for feedforward control so as to achieve decoupling control and improve system dynamic response. Further, a fast sequence decomposition approach is employed to enhance the control characteristics of the whole system. Finally, the effectiveness of proposed control is validated through case studies for a 2 MW BDFIG based wind generation system. The results demonstrate that the proposed control can effectively achieve the control objectives of overall wind turbine system under grid voltage unbalance and provide excellent dynamic and stable performance.

/pdf/modeling-and-coordinated-control-design-for-brushless-doubly-3z4o6um33c.pdf

Modeling and Coordinated Control Design for Brushless Doubly-Fed Induction Generator-Based Wind Turbine to Withstand Grid Voltage Unbalance

A brushless double-fed induction generator (BDFIG) has shown tremendous success in wind turbines due to its robust brushless design, smooth operation, and variable speed characteristics. However, the research regarding controlling of machine during low voltage ride through (LVRT) need greater attention as it may cause total disconnection of machine. In addition, the BDFIG based wind turbines must be capable of providing controlled amount of reactive power to the grid as per modern grid code requirements. Also, a suitable dynamic response of machine during both normal and fault conditions needs to be ensured. This paper, as such, attempts to provide reactive power to the grid by analytically calculating the decaying flux and developing a rotor side converter control scheme accordingly. Furthermore, the dynamic response and LVRT capability of the BDFIG is enhanced by using one of the very intelligent optimization algorithms called the Salp Swarm Algorithm (SSA). To prove the efficacy of the proposed control scheme, its performance is compared with that of the particle swan optimization (PSO) based controller in terms of limiting the fault current, regulating active and reactive power, and maintaining the stable operation of the power system under identical operating conditions. The simulation results show that the proposed control scheme significantly improves the dynamic response and LVRT capability of the developed BDFIG based wind energy conversion system; thus proves its essence and efficacy.

Dynamic response and low voltage ride-through enhancement of brushless double-fed induction generator using Salp swarm optimization algorithm

Fuel cells guarantee ecological ways of electricity production by promising zero emissions. Proton exchange membrane fuel cells (PEMFCs) are considered one of the safest methods, with a low operating temperature and maximum conversion efficiency. In order to harness the full potential of PEMFC, it is imperative to ensure the membrane’s safety through appropriate control strategies. However, most of the strategies focus on fuel economy along with viable fuel cell life, but they do not assure constant output voltage characteristics. A comprehensive design to regulate and boost the output voltages of PEMFC under varying load conditions is addressed with dynamic integral sliding mode control (DISMC) by combining the properties of both the dynamic and integral SMC. The proposed system outperforms in robustness against parametric uncertainties and eliminates the reaching phase along with assured stability. A hardware test rig consisting of a portable PEMFC is connected to the power converter using the proposed technique that regulates voltage for varying loads and power conditions. The results are compared with a proportional integral (PI) based system. Both simulation and hardware results are provided to validate the proposed technique. The experimental results show improvements of 35.4%, 34% and 50% in the rise time, settling time and robustness, respectively.

/pdf/fuel-cell-voltage-regulation-using-dynamic-integral-sliding-2a4m4a0r.pdf

Fuel Cell Voltage Regulation Using Dynamic Integral Sliding Mode Control

The brushless doubly-fed generator (BDFG) is a kind of novel machine, which can be regarded as a combination of conventional synchronous and asynchronous motors. Due to its absence of brush and slip rings, BDFG has potential in hydropower generation. The paper first evaluates the feasibility of BDFG for hydropower generation system and verify the proposed control strategy, based on a practical application in Daliang hydropower station.

Application of Brushless Doubly-Fed Machine System in Hydropower Generation

Based on the steady-state mathematical model of the brush-less double-fed machine (BDFM), this paper analyzes the mechanical characteristics of the motor in asynchronous operation mode. In this mode of operation, when the two sets of stator windings of the BDFM are respectively assigned as power winding, they both have characteristics similar to those of the conventional asynchronous motors with the corresponding pole pairs. And then, a 30 kW BDFM is modeled and simulated by finite element analysis. Finally, based on the above conclusions, an asynchronous soft start method suitable for brushless double-fed motor is proposed.

Asynchronous Starting Characteristics and Soft Start Method of the Brushless Doubly-Fed Motor

https://ietresearch.onlinelibrary.wiley.com/doi/pdf/10.1049/rpg2.12022

Dynamic analysis and oscillation elimination of brushless doubly fed wind power generation system during symmetrical voltage dips

The Brushless Doubly-fed Induction Generator (BDFIG) has potential in Wind Power generation due to its absence of brush and slip rings compared to the Doubly-Fed Induction Generator (DFIG). To promote its commercialization process, the BDFIG is required to be able to ride through the grid voltage dips. An improved control strategy using virtual inductance is proposed to reduce the overcurrent caused by grid faults. Theoretical analysis is given to calculate the value of virtual inductance and the utility of the proposed control scheme has been verified by experiment.

Virtual Inductance Control Strategy for Brushless Doubly-Fed Induction Generator During Grid Voltage Dips

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Ming Kong

Author Tools

Chat about Author