Wind Turbines under Power-Grid Partial Islanding

The load demand to the power grid, as well as the interest in clean and low-cost energy resources, lead to the high integration of wind power plants into the power system grid. There are grid code standards that are set for the design and integration of these wind power plants. These codes often look at the design operation of the wind power plant in islanded mode, where possible analysis of the most sensitive power system quantities such as voltage, frequency, reactive power, etcetera is done. Therefore, attention needs to be paid to the application of these codes to keep the design and integration of wind power plants well standardized as much as possible. The purpose of this research is to review and discuss the literature and theory about the design of the wind turbine generators, model the wind power plant, and integrate it into the power system grid while adhering to the grid code requirements. Keywords— Integration, Point of Common Coupling (PoCC), Renewable Power Plant (RPP)...

EasyChair, 2021

The load demand to the power grid, as well as the interest in clean and low-cost energy resources, lead to the high integration of wind power plants into the power system grid. There are grid code standards that are set for the design and integration of these wind power plants. These codes often look at the design operation of the wind power plant in islanded mode, where possible analysis of the most sensitive power system quantities such as voltage, frequency, reactive power, etcetera is done. Therefore, attention needs to be paid to the application of these codes to keep the design and integration of wind power plants well standardized as much as possible. The purpose of this research is to review and discuss the literature and theory about the design of the wind turbine generators, model the wind power plant, and integrate it into the power system grid while adhering to the grid code requirements.

ARPN journal of engineering and applied sciences, 2015

This paper investigates the grid-connection problems for wind turbines and offers appropriate solutions. This paper provides a simulation for the power system during the faults by using PSCAD and MATLAB. A comparison between using PSCAD and MATLAB in electrical circuits is investigated in this paper. The power system simulation used in this paper consists of an AC generator of a power rating 1 MVA and a wind turbine generator 2MVA. The grid frequency before and after the fault is also investigated in this paper. It investigates many case studies and the corresponding analysis for the waveforms and the data involved. The results of the simulation study show that the location of the fault is a very important factor in the power system analysis. Faults in the transmission lines have a dangerous effect in the wind turbines, which are connected to the electrical grid. The results of the simulation also show that the wind turbine, in this case study, supported the electrical grid to maintain the frequency in the same value.

The Journal of Engineering, 2019

This article proposes a new control paradigm for the seamless operation of a permanent magnet synchronous generator (PMSG) based wind energy conversion system (WECS) in both islanded and grid-connected modes. Conventionally, grid-connected WECS are controlled to extract the maximum power from the wind, known as maximum power point tracking (MPPT). However, in islanded operation, the objective is to control the power generated from the WECS to match the load demand, which here is called load following power generation (LFPG). This article proposes a power management system (PMS) which integrates the MPPT and LFPG capabilities of the WECS into a single-control paradigm. This enables the WECS to seamlessly achieve MPPT in grid operation, LFPG in islanded mode and low-voltage ride-through (LVRT) during fault. The proposed scheme is validated using MATLAB/SIMULINK simulations.

Global Journal of Computer Sciences: Theory and Research, 2018

Wind energy generation has attracted great interests in recent years. Doubly-fed induction generator (DFIG) for wind turbines (WTs) are largely deployed, because variable-speed WTs have many advantages over fixed-speed generation such as increased energy capture, operation at maximum power point, improved efficiency and power quality. This paper presents the operation and vector control of a DFIG system, where the stator is connected directly to a stiff grid and the rotor is connected to the grid through bidirectional back-to-back AC–DC–AC converter. The basic operational characteristics, mathematical model of the aerodynamic system and vector control technique, which is used to obtain decoupled control of powers, are investigated using the software Matlab/Simulink. Keywords: Wind turbine, doubly-fed induction generator, active and reactive power controller.

2021 1st International Conference on Power Electronics and Energy (ICPEE), 2021

The cumulative infiltration of small sized Renewable Energy Sources (RES) into prevailing grid has generated novel challenges. µG (µG) is a controllable unit for the grid as well as for the user side. It can meet its distinctive demands, ease feeder loss and safeguard local voltage stability. They can be coupled and separated from the grid to facilitate both grid-connected and islanded mode of operation. Islanding is a condition in which a distribution system gets electrically secluded from the rest of the network, owing to a fault at inflow side or any other disturbance, and yet remains to be strengthened by the Distributed Generation (DG) system coupled to it. Keeping track of different parameters alike Voltage, frequency, Impedance, real power(P), reactive power(Q), voltage(V) at the point of common coupling (PCC) is of great use to decide about islanding at any desired location. In today's scenario islanding detection is a vital phase. This study reviews about various island...

2018

This thesis deals with the operation and control of VSC based grid connected wind farms. The fast growth of wind generation has led to concern about the effect of wind power on the stability of the electric grid. Therefore, it is essential to analyze the effect of wind farm penetration into power system on its frequency and other characteristics, especially frequency drop when unexpected generation loss due to a fault in the grid system or load increase occurs. During severe network disturbance such as a short circuit fault, the terminal voltage of wind farm decreases significantly and active power from wind farm cannot be supplied to the grid system. New studies must be performed in order to evaluate the behavior of the wind farms after severe faults and improve the design of the wind farms in an efficient and economical way. Therefore, the interaction between wind farm and grid system from points of view of transient and steady state characteristics has become a very important issue to be analyzed. The Fixed Speed Wind Turbines with Squire Cage Induction Generators (FSWT-SCIGs) are widely used in wind farm due to their advantages of mechanical simplicity, robust construction, and lower cost. However, the FSWT-SCIG directly connected to the grid does not have any LVRT

EasyChair, 2021

The load demand to the power grid, as well as the interest in clean and low-cost energy resources, lead to the high integration of wind power plants into the power system grid. There are grid code standards that are set for the design and integration of these wind power plants. These codes often look at the design operation of the wind power plant in islanded mode, where possible analysis of the most sensitive power system quantities such as voltage, frequency, reactive power, etcetera is done. Therefore, attention needs to be paid to the application of these codes to keep the design and integration of wind power plants well standardized as much as possible. The purpose of this research is to review and discuss the literature and theory about the design of the wind turbine generators, model the wind power plant, and integrate it into the power system grid while adhering to the grid code requirements.

European Transactions on Electrical Power, 2008

Modern power generation systems for wind turbines are often based on the rotor fed slip-ring machines. Power electronics converter provides the slip power, and also the reactive power for excitation of the generator during standalone operation. This way the isolated load can be supplied even if the grid has failed. Stator voltage in an autonomous operation is controlled using vectorial phase locked loop (PLL) structure; therefore the information about mechanical speed or angular position of the rotor is eliminated from the control method. The second PLL is also used for synchronization of the generated voltage with the grid voltage. Voltages synchronization is necessary for soft connection and protection of the supplied load from the rapid change of the supply voltage phase. The grid-connected doubly fed induction generator (DFIG) can be useful after grid fault; however, the mains outage detection methods are necessary for fast disconnection after grid failures.

IEEE Transactions on Energy Conversion, 2006

Due to its many advantages such as the improved power quality, high energy efficiency and controllability, etc. the variable speed wind turbine using a doubly fed induction generator (DFIG) is becoming a popular concept and thus the modeling of the DFIG based wind turbine becomes an interesting research topic. Fundamental frequency models have been presented but these models are often complex with significant numerical overhead as the power converter block consisting of power control, rotor side and grid side converter control and DC link are often simulated in detail. This paper develops a simple DFIG wind turbine model in which the power converter is simulated as a controlled voltage source, regulating the rotor current to meet the command of real and reactive power production. This model has the form of traditional generator model and hence is easy to integrate into the power system simulation tool such as PSS/E. As an example, the interaction between the Arklow Bank Wind Farm and the Irish National Grid was simulated using the proposed model. The model performance and accuracy was also compared with the detailed model developed by DIgSILENT. Considering the simplification adopted for the model development, the limitation and applicability of the model were also discussed in this paper.