scholarly journals Potential of Slip Synchronous Wind Turbine Systems: Grid Support and Mechanical Load Mitigation

Energies ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4995
Author(s):  
Dillan Kyle Ockhuis ◽  
Maarten Kamper
Keyword(s):  
Wind Turbine ◽  
Dynamic Stability ◽  
High Speed ◽  
Reactive Power ◽  
Low Voltage ◽  
Mechanical Load ◽  
Short Circuit ◽  
Power Converter ◽  
Grid Services ◽  
Grid Codes

Wind power penetration into existing electrical power systems continues to experience year-on-year growth. Consequently, modern wind turbine systems (WTS) are required to comply with relevant grid codes and provide ancillary grid services to assist with overall grid stability. Adhering to these grid codes and services can cause additional mechanical loading on WTS, which can result in a reduction in service life of some of the drivetrain components, and instability if a sufficient means of damping is not present in the drivetrain. In this paper, a dynamic simulation model of a Type 1, direct grid-connected, fixed-speed (FS) slip-synchronous wind turbine system (SS-WTS) is developed to investigate its dynamic stability in response to the additional mechanical loads imparted onto it during transient events on the grid. The SS-WTS is not equipped with a power converter and, consequently, an understanding of its dynamic stability is critical to evaluate its ability to assist with grid services and maintain stability during transient grid conditions such as low-voltage ride-through (LVRT) events. An analytical transfer function model of a 1.5 MW geared direct grid-connected SS-WTS was derived and implemented in MATLAB/Simulink. It was found that the SS technology provides significant damping to the WTS drivetrain while maintaining dynamic stability during a severe LVRT event. Moreover, it was found that the degree of damping is directly proportional to the value of rated slip, and that high-speed drivetrains provide a greater degree of damping for a given value of rated slip. Furthermore, it is shown that the SS-WTS has the ability to assist with grid services such as primary frequency response, short-circuit strength, and reactive power compensation.

scholarly journals Super-Twisting Sliding Mode Control for Gearless PMSG-Based Wind Turbine

Complexity ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-15 ◽  
Author(s):  
Mojtaba Nasiri ◽  
Saleh Mobayen ◽  
Quan Min Zhu
Keyword(s):  
Wind Turbine ◽  
Reactive Power ◽  
Low Voltage ◽  
Sliding Mode ◽  
Synchronous Generator ◽  
Voltage Regulation ◽  
Point Tracking ◽  
Chattering Free ◽  
Grid Codes ◽  
Grid Side

In recent years, the complexities of wind turbine control are raised while implementing grid codes in voltage sag conditions. In fact, wind turbines should stay connected to the grid and inject reactive power according to the new grid codes. Accordingly, this paper presents a new control algorithm based on super-twisting sliding mode for a gearless wind turbine by a permanent magnet synchronous generator (PMSG). The PMSG is connected to the grid via the back-to-back converter. In the proposed method, the machine side converter regulates the DC-link voltage. This strategy improves low-voltage ride through (LVRT) capability. In addition, the grid side inverter provides the maximum power point tracking (MPPT) control. It should be noted that the super-twisting sliding mode (STSM) control is implemented to effectively deal with nonlinear relationship between DC-link voltage and the input control signal. The main features of the designed controller are being chattering-free and its robustness against external disturbances such as grid fault conditions. Simulations are performed on the MATLAB/Simulink platform. This controller is compared with Proportional-Integral (PI) and the first-order sliding mode (FOSM) controllers to illustrate the DC-link voltage regulation capability in the normal and grid fault conditions. Then, to show the MPPT implementation of the proposed controller, wind speed is changed with time. The simulation results show designed STSM controller better performance and robustness under different conditions.

An Investigation of the Low Voltage Ride through Function of GE DFIG Wind Turbines for Electro-Mechanical Simulations

2012 ◽  
Vol 608-609 ◽  
pp. 537-542
Author(s):  
Zhao Jun Meng
Keyword(s):  
Wind Turbine ◽  
Large Scale ◽  
Low Voltage ◽  
Short Circuit ◽  
Wind Farms ◽  
Power Converter ◽  
System Stability ◽  
Total System ◽  
Detailed Model ◽  
Low Voltage Ride Through

Doubly-fed induction generator (DFIG) wind turbine has become the most widely used wind turbine in wind farms, since it presents noticeably advantages such as decoupled controls of active and reactive powers, and the use of a power converter with a rated power of 25% of total system power. As the penetration of wind power in power system increases, it is required that the wind turbine remained connected and actively contributed to the system stability during and after faults and disturbance. One common approach for a DFIG to obtain such low voltage ride through (LVRT) function is to install a crowbar circuit across its rotor terminals, which short circuit the rotor side converter when over-current is detected in the rotor. A detailed model of LVRT function normally requires electromagnetic simulations. However, the time consuming computational process is prohibitive for the studies of the integration of wind farms into large scale power systems. Electromechanical simulations are more suitable for such engineering applications. GE has incorporated the LVRT function into its recently released DFIG wind turbine model for Electro-mechanical simulations. This paper has implemented this model and verified the effectiveness of the LVRT function.

scholarly journals PMSM low voltage ride through based on Coordinated Control Strategy

2021 ◽  
Vol 248 ◽  
pp. 02005
Author(s):  
Zhang Zhaopeng ◽  
Suo Dongnan
Keyword(s):  
Wind Turbine ◽  
Permanent Magnet ◽  
Control Strategy ◽  
Reactive Power ◽  
Low Voltage ◽  
Short Circuit ◽  
Coordinated Control ◽  
System Control ◽  
Direct Drive ◽  
Grid Side

Based on the analysis of the operation characteristics of the fault of direct-drive permanent magnet wind turbine and the existing protection strategies, in order to improve the low-voltage operation capability of direct-drive permanent magnet wind turbine, a new coordinated control strategy for low-voltage crossing is proposed in this paper, which includes DC brake system control of unloading circuit, double second-order generalized integral phase-locked control, extracting positive and negative sequence of grid voltage and reactive power control on grid side. Based on the common three-phase symmetrical drop fault and asymmetrical fault caused by single grounding short circuit in power grid, PASCAD simulation experiment is conducted to verify the low voltage traversing ability of wind turbine.

Low Voltage Ride through of Wind Turbine Based on New SGSC Converter Structure

2013 ◽  
Vol 448-453 ◽  
pp. 2185-2190 ◽  
Author(s):  
He Nan Dong ◽  
Yun Dong Song ◽  
Gang Wang ◽  
Zuo Xia Xing
Keyword(s):  
Power Systems ◽  
Wind Turbine ◽  
Control Strategy ◽  
Large Scale ◽  
Reactive Power ◽  
Low Voltage ◽  
Short Circuit ◽  
Simulation Software ◽  
Low Voltage Ride Through ◽  
Doubly Fed

The proportion of wind power in power systems is increasing year by year. Large-scale wind turbine off the grid when grid system failures. So the wind turbine needs to low voltage ride through (LVRT) function of wind turbine. Aiming at this problem, which in this article by DIgSILENT simulation software build 1.5MW doubly-fed wind turbine(DFIG) model, using active Crowbar and series grid side converter (SGSC) control strategy to realize the simulation of low voltage ride through of wind turbine. The control strategy of active Crowbar is mainly through the short circuit of rotor side converter to realize LVRT, and needs to be matched with the active and reactive power control strategy. SGSC is a novel converter structure, which mainly through compensating stator flux drop to realize LVRT. Finally this two kinds of control strategies were compared, demonstrated SGSC control strategy can achieve the low voltage ride through capabilities of the doubly-fed wind turbine.

scholarly journals Validating Response of AC Microgrid to Line-to-Line Short Circuit in Islanded Mode Using Dynamic Analysis

2019 ◽  
pp. 1-15
Author(s):  
Maruf A. Aminu
Keyword(s):  
Dynamic Response ◽  
Wind Turbine ◽  
Power Flow ◽  
Reactive Power ◽  
Short Circuit ◽  
Operating Mode ◽  
Superior Performance ◽  
Induction Generators ◽  
Bidirectional Power Flow ◽  
Control Regime

This paper is presented in an attempt to validate the dynamic response of a microgrid to line-to-line short circuit. The microgrid components include two identical Wind Turbine Generators (WTGs) tied to a 100MVA, 13.8kV utility via a Point of Common Coupling (PCC). The utility-microgrid testbed is modeled in SIMPOWERSystems® using two Doubly-Fed Induction Generators (DFIGs) in the microgrid side. While in islanded operating mode, line-to-line short circuit fault is applied at 6.0s and withdrawn at 8.0s, obtaining a 50.0s dynamic response of the system for different fault locations, under voltage and reactive power control regimes of the wind turbine controller. For measurement purpose, the absolute value of the stator complex voltage is transformed to  reference frame. Bidirectional power flow between the two feeders is established in the study. The study also confirms that the microgrid composed of DFIGs offer reactive power management capability, particularly by presenting superior performance when stressed under Q control regime than under V control regime. Finally, the response of the testbed to line-to-line short circuit has been validated and shown to be consistent with established short circuit theory.

scholarly journals Research on Safety Technology for High-Speed Interruption for Mining Flameproof Movable Substation

Energies ◽  
2020 ◽  
Vol 13 (4) ◽  
pp. 934
Author(s):  
Yanwen Wang ◽  
Le Wang ◽  
Sven G. Bilén ◽  
Yan Gao
Keyword(s):  
Solid State ◽  
High Speed ◽  
Single Phase ◽  
Low Voltage ◽  
Short Circuit ◽  
Rate Of Change ◽  
Simulation Experiments ◽  
Gas Detonation ◽  
Ultra High Speed ◽  
Short Circuit Fault

Due to the working condition of low-voltage cabling from the mining flameproof movable substation to the loads of the mining face being poor, it is easy to cause various external mechanical damages to the cable sheaths. Furthermore, a single-phase earth leakage fault or short-circuit fault can occur when the low-voltage cable sheaths are damaged, and electric sparks caused by these faults can lead to a gas explosion. As the gas detonation time caused by the above faults is usually more than 5 ms, the high-speed interruption solid-state switch which controls the cables must cut off the current within 3 ms. This requires the action time of the solid-state switch to be less than 1 ms, and at the same time, the sampling and calculation time of the relay protection must be less than 2 ms. Based on these problems, this paper proposes the use of a high-speed solid-state circuit breaker (SSCB) topology at the neutral point of transformer, and analyzes the conduction mechanism and shut-off mechanism of the current of the SSCB. It presents an ultra-high-speed algorithm based on pattern recognition of single-phase earth leakage fault protection, and an ultra-high-speed algorithm of short-circuit fault which is based on the rate-of-change of the current. Finally, through computer simulation experiments and semi-physical simulation experiments, the feasibility of the above three technologies is verified to ensure that when a single-phase earth leakage fault or short-circuit fault occurs in the low-voltage cable, the solid-state switch which is installed in the mining flameproof movable substation will cut off the current within 3 ms.

scholarly journals Photovoltaic Power Converter Management in Unbalanced Low Voltage Networks with Ancillary Services Support

Energies ◽  
2019 ◽  
Vol 12 (6) ◽  
pp. 972 ◽  
Author(s):  
Fermín Barrero-González ◽  
Victor Pires ◽  
José Sousa ◽  
João Martins ◽  
María Milanés-Montero ◽  
...  
Keyword(s):  
Power Flow ◽  
Reactive Power ◽  
Low Voltage ◽  
Renewable Energy Sources ◽  
Distribution Network ◽  
Power Converter ◽  
Maximum Energy ◽  
Practical Implementation ◽  
Network Operation ◽  
The Impact

The proliferation of residential photovoltaic (PV) prosumers leads to detrimental impacts on the low-voltage (LV) distribution network operation such as reverse power flow, voltage fluctuations and voltage imbalances. This is due to the fact that the strategies for the PV inverters are usually designed to obtain the maximum energy from the panels. The most recent approach to these issues involves new inverter-based solutions. This paper proposes a novel comprehensive control strategy for the power electronic converters associated with PV installations to improve the operational performance of a four-wire LV distribution network. The objectives are to try to balance the currents demanded by consumers and to compensate the reactive power demanded by them at the expense of the remaining converters’ capacity. The strategy is implemented in each consumer installation, constituting a decentralized or distributed control and allowing its practical implementation based on local measurements. The algorithms were tested, in a yearly simulation horizon, on a typical Portuguese LV network to verify the impact of the high integration of the renewable energy sources in the network and the effectiveness and applicability of the proposed approach.

scholarly journals Techniques for Ensuring Fault Ride-Through Capability of Grid Connected DFIG-Based Wind Turbine Systems: A Review

2021 ◽  
Vol 18 (1) ◽  
pp. 39-46
Author(s):  
M. Shuaibu ◽  
A.S. Abubakar ◽  
A.F. Shehu
Keyword(s):  
Renewable Energy ◽  
Wind Turbine ◽  
Electricity Market ◽  
Energy Demand ◽  
Reactive Power ◽  
Short Circuit ◽  
Renewable Energy Sources ◽  
Dynamic Performance ◽  
Energy Sources ◽  
Fault Ride Through

Renewable energy sources (RES) are being integrated to electrical grid to complement the conventional sources to meet up with global electrical energy demand. Among other RES, Wind Energy Conversion Systems (WECS) with Doubly Fed Induction Generator (DFIG) have gained global electricity market competitiveness because of the flexible regulation of active and reactive power, higher power quality, variable speed operation, four quadrant converter operation and better dynamic performance. Grid connected DFIG-based WECS are prone to disturbances in the network because of direct connection of stator windings to grid. The ability of the Wind Turbine (WT) to remain connected during grid faults is termed the Fault Ride-Through (FRT) capability. The grid code requirement for integrating the DFIG-based WTs to power networks specified that they must remain connected and support the grid stability during grid disturbances of up to 1500 ms. The use of compensation devices offers the best FRT compliance thereby protecting the DFIG and the converters from voltage fluctuations and over currents during the grid fault. The paper presents a review of techniques employed in ensuring FRT compliance. The article also proposes the state-of-the-art techniques for compensating voltage sag/swell and limiting the fault short-circuit current. Keywords: Renewable energy sources, DFIG, wind turbine system, fault ride-through, grid codes, dual-functional DVR

scholarly journals Steady-state modeling and analysis of PWM current source drives

2021 ◽  
Author(s):  
Behrang Azizi Ghanad
Keyword(s):  
Steady State ◽  
Low Voltage ◽  
Mechanical Load ◽  
Short Circuit ◽  
Current Source ◽  
Parameter Tuning ◽  
Simulation Software ◽  
Drive System ◽  
State Condition ◽  
Steady State Condition

Current source converter based ac motor drives are increasingly used in medium voltage high power applications due to their simple converter topology, inherent four-quadrant operation, reliable short circuit protection and motor friendly waveforms. The behavior of the current source drive system in the steady state condition is studied in this thesis. The main objective of this investigation is to optimize the dc link inductance, which is one of the most expensive components of the drive system. The first research focus of this thesis is to model the current source drive system in steady state condition. Different parts of the drive system such as the induction motor, mechanical load and the complicated field oriented control (FOC) scheme are simplified for the steady state operation mode. This model has two main features: 1) substantially reduced simulation time, and 2) simplified control loop design without any control parameter tuning and control instability problem. Secondly, the characteristic of the dc link circuit is investigated using the developed steady state drive system model in MATLAB Simulink. The effect of the cd link inductance on the input LC resonant frequency is studied. The value of the dc current ripple is calculated under different conditions, and the effects of different system parameters on the ripple value is investigated. Furthermore, a user-friendly simulation software is developed for the dc choke optimization. Experiments are conducted on a low-voltage (30hp, 480V) current source drive system test setup at Rockwell Automation Canada, with which the developed simulation model is verified.

scholarly journals Enhancement of Low Voltage Ride through Capability for DFIG based Wind Turbine with STFCL, DVR and Energy Storage System

2019 ◽  
Vol 8 (2) ◽  
pp. 2882-2886
Keyword(s):  
Wind Turbine ◽  
Reactive Power ◽  
Low Voltage ◽  
Storage System ◽  
Energy Storage System ◽  
Low Voltage Ride Through ◽  
Induction Generators ◽  
Collaborative Control ◽  
Switch Type ◽  
Doubly Fed

A Switch type fault current limiter in coordination with DVR is presented in this paper for Wind turbine generators that consist of doubly fed induction generators in order to full fill Low voltage ride through requirements in grid systems. The position of in-statement, the simulation and the methods for enhancement of LVRT functioning are represented. Collaborative control between the STFCL and a combination of Reactive power control and Inductance emulating control are used to enable the doubly fed induction generator to generate reactive power and ensure that the system remains safe even during faults in the grid. A different type of fault conditions are examined under both normal conditions and while the proposed system is attached.

Sign in / Sign up

Export Citation Format

Share Document