Coordinated control of rotor and grid sides converters in DFIG based wind turbines for providing optimal reactive power support and voltage regulation

Doubly fed induction generator (DFIG) is a widely spread technology in modern wind turbines (WT) due to its capability to operate with variable speed, partial scale power converter, and ability to control active and reactive power independently. The main drawback of DFIG is its complicated protection systems. In the chapter, several strategies for DFIG protection are reviewed, and the authors provide a conclusion about their advantages. Penetration of renewable energy sources (in particular, wind power) have a huge impact on power systems; thus, wind turbines should be considered as conventional generation units in terms of frequency and voltage regulation. Modern grid codes require WT stay connected during grid fault and be capable to provide appropriate grid support. Therefore, it is important to implement a DFIG protection system that could meet grid code requirements.

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Coordinated Control of Active and Reactive Power Compensation for Voltage Regulation with Enhanced Disturbance Rejection Using Repetitive Vector-Control

Energies ◽

10.3390/en13112812 ◽

2020 ◽

Vol 13 (11) ◽

pp. 2812 ◽

Cited By ~ 1

Author(s):

Felipe J. Zimann ◽

Eduardo V. Stangler ◽

Francisco A. S. Neves ◽

Alessandro L. Batschauer ◽

Marcello Mezaroba

Keyword(s):

Vector Control ◽

Reactive Power ◽

Low Voltage ◽

Voltage Drop ◽

Coordinated Control ◽

Voltage Regulation ◽

Reactive Power Compensation ◽

Voltage Profile ◽

Promising Alternative ◽

Active And Reactive Power

Voltage profile is one of many aspects that affect power quality in low-voltage distribution feeders. Weak grids have a typically high line impedance which results in remarkable voltage drops. Distribution grids generally have a high R/X ratio, which makes voltage regulation with reactive power compensation less effective than in high-voltage grids. Moreover, these networks are more susceptible to unbalance and harmonic voltage disturbances. This paper proposes an enhanced coordinated control of active and reactive power injected in a distribution grid for voltage regulation. Voltage drop mitigation was evaluated with power injection based on local features, such loads and disturbances of each connection. In order to ensure disturbances rejection like harmonic components in the grid voltages, a repetitive vector-control scheme was used. The injection of coordinated active and reactive power with the proposed control algorithm was verified through simulations and experiments, demonstrating that it is a promising alternative for voltage regulation in weak and low-voltage networks subject to inherent harmonic distortion.

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Grid Voltage Regulation with Optimal Reactive Power Effort by Active Front End Converters

Mediterranean Conference on Power Generation, Transmission, Distribution and Energy Conversion (MEDPOWER 2018) ◽

10.1049/cp.2018.1834 ◽

2018 ◽

Cited By ~ 2

Author(s):

J. Chhor ◽

C. Sourkounis

Keyword(s):

Reactive Power ◽

Voltage Regulation ◽

Grid Voltage ◽

Front End

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Contribution of Voltage Support Function to Virtual Inertia Control Performance of Inverter-Based Resource in Frequency Stability

Energies ◽

10.3390/en14144220 ◽

2021 ◽

Vol 14 (14) ◽

pp. 4220

Author(s):

Dai Orihara ◽

Hiroshi Kikusato ◽

Jun Hashimoto ◽

Kenji Otani ◽

Takahiro Takamatsu ◽

...

Keyword(s):

Reactive Power ◽

Control Function ◽

Current Source ◽

Voltage Control ◽

Frequency Stability ◽

Voltage Regulation ◽

System Stability ◽

Voltage Source ◽

Apparent Difference ◽

Virtual Inertia

Inertia reduction due to inverter-based resource (IBR) penetration deteriorates power system stability, which can be addressed using virtual inertia (VI) control. There are two types of implementation methods for VI control: grid-following (GFL) and grid-forming (GFM). There is an apparent difference among them for the voltage regulation capability, because the GFM controls IBR to act as a voltage source and GFL controls it to act as a current source. The difference affects the performance of the VI control function, because stable voltage conditions help the inertial response to contribute to system stability. However, GFL can provide the voltage control function with reactive power controllability, and it can be activated simultaneously with the VI control function. This study analyzes the performance of GFL-type VI control with a voltage control function for frequency stability improvement. The results show that the voltage control function decreases the voltage variation caused by the fault, improving the responsivity of the VI function. In addition, it is found that the voltage control is effective in suppressing the power swing among synchronous generators. The clarification of the contribution of the voltage control function to the performance of the VI control is novelty of this paper.

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Using Energy Storage Inverters of Prosumer Installations for Voltage Control in Low-Voltage Distribution Networks

Energies ◽

10.3390/en14041121 ◽

2021 ◽

Vol 14 (4) ◽

pp. 1121

Author(s):

Rozmysław Mieński ◽

Przemysław Urbanek ◽

Irena Wasiak

Keyword(s):

Energy Storage ◽

Control Strategy ◽

Reactive Power ◽

Low Voltage ◽

Storage System ◽

Distribution Networks ◽

Energy Storage System ◽

Voltage Regulation ◽

Active Power ◽

Total Power

The paper includes the analysis of the operation of low-voltage prosumer installation consisting of receivers and electricity sources and equipped with a 3-phase energy storage system. The aim of the storage application is the management of active power within the installation to decrease the total power exchanged with the supplying network and thus reduce energy costs borne by the prosumer. A solution for the effective implementation of the storage system is presented. Apart from the active power management performed according to the prosumer’s needs, the storage inverter provides the ancillary service of voltage regulation in the network according to the requirements of the network operator. A control strategy involving algorithms for voltage regulation without prejudice to the prosumer’s interest is described in the paper. Reactive power is used first as a control signal and if the required voltage effect cannot be reached, then the active power in the controlled phase is additionally changed and the Energy Storage System (ESS) loading is redistributed in phases in such a way that the total active power set by the prosumer program remains unchanged. The efficiency of the control strategy was tested by means of a simulation model in the PSCAD/EMTDC program. The results of the simulations are presented.

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