Harmonic Analyzing of the Double PWM Converter in DFIG Based on Mathematical Model

Liu, Jing; Liu, Zhigang

doi:10.3390/en10122087

Cited by 6 publications

(6 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

Section: Fault Current Waveform Featuresmentioning

confidence: 99%

“…If stator voltage drops lightly, DFIG will operate on the condition that still excited by rotor side converter.Under this condition, the fault transient current is rich in harmonics, 27,28 and the waveform shows complex rules. 2 Synchronous generator : The fault current of synchronous generator has been well studied, which also has three components compared with that of DFIG under the condition of crowbar being thrown into.…”

Section: Pilot Protection Based On Time‐domain Waveform Identificationmentioning

confidence: 99%

See 1 more Smart Citation

Novel pilot protection based on time‐domain for transmission line with doubly fed induction generator

Yang

Liu

et al. 2020

Int Trans Electr Energ Syst

View full text Add to dashboard Cite

Large-scale doubly fed induction generator (DFIG) wind farms are integrated into power grid through transmission line. Traditional pilot protection as the main protection is widely used in transmission line. However, when traditional pilot protection is applied to transmission line with DFIG, it may appear undesired tripping. Therefore, this work presents a novel pilot protection based on time-domain waveform identification for transmission line with DFIG. The waveform features of the fault currents provided by DFIG and synchronous generator are analyzed. According to the waveform similarity between prefault and postfault currents, calculated separately at DFIG wind farm side and power grid side, the protection principle is established: when internal faults occur, the waveform similarity calculated at DFIG wind farm side is much lower than that calculated at power grid side; when external faults occur, the waveform similarity calculated at both sides are almost the same. A complete protection flow based on proposed principle is designed. Furthermore, a false data detection method is raised for resisting the influence of noise on the performance of proposed protection. Extensive digital simulations are conducted to verify the principle. The test results indicate that the proposed protection can reliably identify the internal faults and external faults, and also has strong ability to withstand the effects of fault resistance, noise, and communication delay. K E Y W O R D S DFIG, Hausdorff distance algorithm, pilot protection, time-domain waveform identification, transmission line List of Symbols and Abbreviations: Z eq , equivalent impedance of upstream network; I, current sampling sequence; I * , normalized I; max{I}, maximum value in I; min{I}, minimum value in I; k, sampling point label of I; X, waveform set X = {x 1 , x 2 , .…x m }; Y, waveform set Y = {y 1 , y 2 , .…y n };

show abstract

Section: Fault Current Waveform Featuresmentioning

confidence: 99%

Section: Pilot Protection Based On Time‐domain Waveform Identificationmentioning

confidence: 99%

Novel pilot protection based on time‐domain for transmission line with doubly fed induction generator

Yang

Liu

et al. 2020

Int Trans Electr Energ Syst

View full text Add to dashboard Cite

show abstract

“…Then, using the same method in Equations (7)-(10), the small-signal transfer functions G H and G M , which are the transfer matrixes fromd m dq toû m dc and fromd m dq toî m gdq , respectively, can be obtained in Equation (30). Also, similar small-signal transfer functions of the other variables can be obtained:…”

Section: Small-signal Modeling Of the Gsc Circuitmentioning

confidence: 99%

“…It is clear that the main amplified harmonic components are 250.1 (5th harmonic), 349.7 (7th harmonic), 1901 (38th harmonic), 2099.1 (42nd harmonic), 3951.6 (79th harmonic), and 4050.4 Hz (81st harmonic). In fact, 5th and 7th harmonic components mainly exist in RSC and 38th, 42nd, 79th and 81st harmonic components exist both in RSC and GSC [30]. And when the system parameters are not matched well, the existing harmonics both in RSC and GSC will be continuously amplified and interact with each other through the DC link, thereby generating harmonic instability and jeopardizing the power quality and stability of the entire system.…”

Section: Rtds Simulation Verificationmentioning

confidence: 99%

Impedance Modeling and Stability Analysis of the Converters in a Double-Fed Induction Generator (DFIG)-Based System

Chen¹,

Liu²

2019

Energies

Self Cite

View full text Add to dashboard Cite

Harmonic stability of double-fed induction generators (DFIGs) now has become a significant topic because of its harmful impact on power quality issues of the system. Since the double pulse width modulation (PWM) converter is one of the main harmonic sources in DFIGs, it may cause harmonic instability with increasing harmonic contents. Thus, the modeling and stability analyses of PWM converters in DFIGs are essential steps to assess the harmonic stability of DFIGs. Aiming at dual PWM converters, which include the grid side converter (GSC) and the rotor side converter (RSC), this paper divides converters into two parts: circuit modules and control modules. Closed-loop input impedance models of each module are then derived by means of transfer functions. Hence, the stability of the system can be readily predicted through Nyquist diagrams. The contributions of parameters to the system’s harmonic stability are also identified. Finally, time-domain simulations are conducted in a real-time digital simulation (RTDS) system. Simulation results confirm that the established impedance model can effectively reveal the stability of the DFIG-based system and can give critical conditions for the occurrence of harmonic instability.

show abstract

“…DCC methods have been frequently used with the PWM converter. The most commonly used DCC method utilizes vector control theory (dq control) [13][14][15][16]. Coordination transformation is needed in dq control to change the ac signals into dc signals [17].…”

Section: Introductionmentioning

confidence: 99%

Power and Voltage Control for Single-Phase Cascaded H-Bridge Multilevel Converters under Unbalanced Loads

Yang

Yin

Xu³

et al. 2018

Energies

View full text Add to dashboard Cite

The conventional control method for a single-phase cascaded H-bridge (CHB) multilevel converter is vector (dq) control; however, dq control requires complicated calculations and additional time delays. This paper presents a novel power control strategy for the CHB multilevel converter. A power-based dc-link voltage balance control is also proposed for unbalanced load conditions. The new control method is designed in a virtual αβ stationary reference frame without coordinate transformation or phase-locked loop (PLL) to avoid the potential issues related to computational complexity. Because only imaginary voltage construction is needed in the proposed control method, the time delay from conventional imaginary current construction can be eliminated. The proposed method can obtain a sinusoidal grid current waveform with unity power factor. Compared with the conventional dq control method, the power control strategy possesses the advantage of a fast dynamic response. The stability of the closed-loop system with the dc-link voltage balance controller is evaluated. Simulation and experimental results are presented to verify the accuracy of the proposed power and voltage control method.

show abstract

Harmonic Analyzing of the Double PWM Converter in DFIG Based on Mathematical Model

Cited by 6 publications

References 29 publications

Novel pilot protection based on time‐domain for transmission line with doubly fed induction generator

Novel pilot protection based on time‐domain for transmission line with doubly fed induction generator

Impedance Modeling and Stability Analysis of the Converters in a Double-Fed Induction Generator (DFIG)-Based System

Power and Voltage Control for Single-Phase Cascaded H-Bridge Multilevel Converters under Unbalanced Loads

Contact Info

Product

Resources

About