scholarly journals Nonlinear Variable Resistor-Based FCL for Fault Ride-Through Performance Enhancement of DFIG-Based Wind Turbines

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Mehdi Firouzi ◽  
Mohammadreza Shafiee ◽  
Mojtaba Nasiri
Keyword(s):  
Wind Turbines ◽  
Performance Enhancement ◽  
Short Circuit ◽  
Variable Resistor ◽  
Fault Ride Through ◽  
Three Phase ◽  
Bridge Type ◽  
Doubly Fed ◽  
Grid Side ◽  
Short Circuit Fault

Fault ride-through (FRT) requirement is a matter of great concern for doubly fed induction generator (DFIG-) based wind turbines (WTs). This study presents a nonlinear variable resistor- (NVR-) based bridge-type fault current limiter (BFCL) to augment the FRT performance of DFIG-based WTs. First, the BFCL operation and nonlinear control design consideration of the proposed NVR-based BFCL are presented. Then, the NVR-BFCL performance is validated through simulation in PSCAD/EMTDC software. In addition, the NVR-based BFCL performance is compared with the fixed resistor- (FR-) based BFCL for a three-phase symmetrical short circuit fault at the grid side. Simulation results reveal that the NVR-based BFCL provides a smooth and effective FRT scheme and outperforms the FR-based BFCL.

scholarly journals Shafting Torsional Vibration Analysis of 1000 MW Unit under Electrical Short-Circuit Fault

2021 ◽  
Vol 11 (19) ◽  
pp. 9205
Author(s):  
Honggang Pan ◽  
Yunshi Wu ◽  
Zhiyuan Pang ◽  
Yanming Fu ◽  
Tianyu Zhao
Keyword(s):  
Short Circuit ◽  
Power Grid ◽  
Two Phase ◽  
Shaft System ◽  
Three Phase ◽  
Speed Fluctuation ◽  
Grid Side ◽  
Generator Terminal ◽  
The Impact ◽  
Short Circuit Fault

Taking a 1000 MW turbine generator as the research object, the short-circuit fault in electrical disturbance is analyzed. Since it is very difficult to carry out fault analysis experiments and research on actual systems, simulation analysis is one of the more effective means of electrical fault diagnosis; the simulation’s results approach the actual behavior of the system and are ideal tools for power system analysis, and can provide an empirical basis for practical applications. The short-circuit fault model of the SIMULINK power system is built to analyze the two types of faults of generator terminals short-circuit and power grid short-circuit. The impact load spectrum, fault current and speed fluctuation between low-voltage rotors were extracted and analyzed. The conclusion is that the impact value of electromagnetic torque at the generator terminal is greater than that on the power grid side. The impact value of a two-phase short-circuit at the generator terminal is the largest, and that of a three-phase short-circuit on the power grid side is the smallest. The transient impulse current of a three-phase short-circuit at any fault point is greater than that of a two-phase short-circuit; the impulse current of the grid side short-circuit is much greater than that of the generator terminal short-circuit; the speed fluctuation and fluctuation difference caused by the three-phase short-circuit in the grid side are the largest. The alternating frequency of the transient electromagnetic force of the four kinds of faults avoids the natural frequency of the torsional vibration of the shaft system, and the torsional resonance of the shaft system in the time domain of the short-circuit fault will not appear. However, after the fault is removed, the residual small fluctuation torque in the system has a potential impact on the rotor system. This research shows an analysis of the structural integrity and safe operation of turbine generator units after a short-circuit fault, which can not only be applied to engineering practice, but also provide a theoretical basis for subsequent research.

Variable-Speed Wind Turbines with Doubly-Fed Induction Generators Part III: Model with the Back-to-back Converters

2003 ◽  
Vol 27 (2) ◽  
pp. 79-91 ◽  
Author(s):  
Vladislav Akhmatov
Keyword(s):  
Wind Turbines ◽  
Short Circuit ◽  
Practical Investigations ◽  
System Stability ◽  
Variable Speed ◽  
Induction Generators ◽  
Doubly Fed Induction Generators ◽  
Set Up ◽  
Doubly Fed ◽  
Short Circuit Fault

A model of the back-to-back converter is set up and implemented in the simulation tool PSS/E as a user-developed model. This model is applied with that of the doubly-fed induction generator (DFIG), described in previous parts of this work [parts II and I]. The latter models variable-speed wind turbines in power stability investigations. Subjected to a short circuit fault, there will be a risk of converter blocking, followed by tripping of the wind turbine [1, 3]. The main reasons of blocking are over-current in the rotor converter and over-voltage in the dc-link. The DFIG model, with representation of the back-to-back converter, results in (a) more accurate replication of the current in the rotor converter and (b) improved computation of the dc-link voltage. These improvements are compared with the model with representation of the rotor converter only. Hence, the DFIG model with representation of the back-to-back converters might be preferred, in practical investigations of power system stability, to models with representation of the rotor converter only.

Symmetrical Short Circuit Current Characteristics of Doubly Fed Induction Generator Wind Turbine with Crowbar Protection

2012 ◽  
Vol 512-515 ◽  
pp. 782-787
Author(s):  
Jia Jun Zhai ◽  
Bu Han Zhang ◽  
Kui Wang ◽  
Wen Shao ◽  
Cheng Xiong Mao
Keyword(s):  
Wind Turbine ◽  
Wind Turbines ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Induction Generator ◽  
Doubly Fed Induction Generator ◽  
Operating Characteristics ◽  
Doubly Fed ◽  
Crowbar Protection ◽  
Short Circuit Fault

Doubly fed induction generator (DFIG) is now becoming one of most widely used wind turbines in global market for wind power generation, due to its outstanding advantages. However, the DFIG is sensitive to grid faults. The DFIG will have to be removed from the grid if there’s no protection appliance in it. Therefore, the crowbar protection is widely used in the world for improving the low voltage ride-through ability of wind turbines. This paper analysed the operating characteristics and short-circuit current of DFIG under symmetrical short-circuit fault with respect to different sags to grid voltage, which on the basis of DFIG wind turbine with crowbar protection. And the expressions of short-circuit current under symmetrical short-circuit fault for DFIG were derived. The effectiveness of the expression was simulated in PSCAD/EMTDC.

scholarly journals Inter-Turn Short-Circuit Fault Ride-Through for DFIG Wind Turbines

2020 ◽  
Vol 53 (2) ◽  
pp. 12757-12762
Author(s):  
Kuichao Ma ◽  
Jiangsheng Zhu ◽  
Mohsen Soltani ◽  
Amin Hajizadeh ◽  
Zhe Chen
Keyword(s):  
Wind Turbines ◽  
Short Circuit ◽  
Fault Ride Through ◽  
Short Circuit Fault

scholarly journals Wind Farm Power Optimization and Fault Ride-Through under Inter-Turn Short-Circuit Fault

Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3072
Author(s):  
Kuichao Ma ◽  
Mohsen Soltani ◽  
Amin Hajizadeh ◽  
Jiangsheng Zhu ◽  
Zhe Chen
Keyword(s):  
Wind Farm ◽  
Power Optimization ◽  
Short Circuit ◽  
Doubly Fed Induction Generator ◽  
Fault Ride Through ◽  
Proper Power ◽  
Power Limit ◽  
Doubly Fed ◽  
Short Circuit Fault ◽  
Operational Capacity

Inter-Turn Short Circuit (ITSC) fault in stator winding is a common fault in Doubly-Fed Induction Generator (DFIG)-based Wind Turbines (WTs). Improper measures in the ITSC fault affect the safety of the faulty WT and the power output of the Wind Farm (WF). This paper combines derating WTs and the power optimization of the WF to diminish the fault effect. At the turbine level, switching the derating strategy and the ITSC Fault Ride-Through (FRT) strategy is adopted to ensure that WTs safely operate under fault. At the farm level, the Particle Swarm Optimization (PSO)-based active power dispatch strategy is used to address proper power references in all of the WTs. The simulation results demonstrate the effectiveness of the proposed method. Switching the derating strategy can increase the power limit of the faulty WT, and the ITSC FRT strategy can ensure that the WT operates without excessive faulty current. The PSO-based power optimization can improve the power of the WF to compensate for the power loss caused by the faulty WT. With the proposed method, the competitiveness and the operational capacity of offshore WFs can be upgraded.

Research on the Network Based Protection to Settle the Distribution Networks Three-Phase Short-Circuit Faults with Distributed Generators

2014 ◽  
Vol 496-500 ◽  
pp. 1457-1463
Author(s):  
Yan Xu ◽  
Qin Cheng Yuan ◽  
Xiao Yun Huang ◽  
Lan Jiang
Keyword(s):  
Distributed Generation ◽  
Short Circuit ◽  
Current Source ◽  
Distribution Networks ◽  
Control Mode ◽  
Equivalent Model ◽  
Network Protection ◽  
Fault Ride Through ◽  
Three Phase ◽  
Short Circuit Fault

A model is established to research on the applicability of network protection in theory. In this model, distributed power generation with constant power (PQ) control mode which is equivalent to a voltage control current source is taken as the research object. Fault ride-through control theory is used to analyze the influence on the network protection exerted by three-phase short-circuit fault. In this paper, the equivalent model of the distributed generation is offered firstly. Then the three-phase short-circuit fault characteristics are illustrated based on the equations of the access points voltage and the distributed generations current. In the end, a simulation model is built to verify that the network protection can be applied to settle the three-phase short-circuit fault in the distributed network with distributed generation.

Research on Characteristics of Stator and Rotor Fault Current of DFIG

2015 ◽  
Vol 1092-1093 ◽  
pp. 325-331
Author(s):  
Hong Bo Zhao ◽  
Wen Hui Shi ◽  
Hao Zha ◽  
Jing Wu
Keyword(s):  
Power System ◽  
Wind Turbines ◽  
Short Circuit ◽  
Transient Processes ◽  
Stable Operation ◽  
Fault Current ◽  
Electromagnetic Transient ◽  
Fault Ride Through ◽  
Three Phase ◽  
Current Characteristics

The abrupt dip of grid voltage would provoke a series of electromagnetic transient processes in stator and rotor of DFIG, which would threat the security of wind turbines fault ride through (LVRT) and stable operation of power system. Analyzing the fault current characteristics of DFIG is very useful to improve the LVRT strategy and adjust the relay protection setting of power system. In this paper, electromagnetic transient processes of DFIG are given a detail analysis after protection circuit of DFIG works due to the dip of three phase voltage in system. Then, the general expression of stator and rotor fault current is derived, and the validity of this method is verified. At last, the influences of the system short-circuit capacity and wind turbines accessing capacity on the fault current and system protections are analyzed when the wind turbines are accessed to the distribution network.

Sign in / Sign up

Export Citation Format

Share Document