Iterative approach to impedance model for small‐signal stability analysis

Wang, Liang; Peng, Jingyu; You, Yuyang; Ma, Hongwei

doi:10.1049/iet-rpg.2018.5265

Cited by 6 publications

(3 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore, the influence of the generator on this new type of electrical oscillation can be ignored. In addition, Z sg (s) is relatively small compared with Z line (s) in the investigated MFO frequency region, especially when the local grid is weak (Wang et al, 2019). Therefore, only the impedance of the transmission line is considered in this study for the sake of simplified analysis.…”

Section: Impedance Model Of the Local Gridmentioning

confidence: 99%

Impedance Modeling and Analysis of Medium-Frequency Oscillation Caused by VSC-HVDC Connected to Local Weak Grid and DFIG-Based Wind Farms

et al. 2021

View full text Add to dashboard Cite

In the northwest of China, a strategy to transmit the wind-thermal–bundled power from the local grid and doubly fed induction generator (DFIG)–based wind farms through a voltage source converter–based HVDC (VSC-HVDC) can be widely applied. However, since the local grid is usually weak, a new type of electrical oscillation in the medium-frequency region may occur in the sending-end converter (SEC) of VSC-HVDC with PQ-control. The mechanism of this oscillation caused by the interaction between the DFIG, local grid, and SEC is not entirely understood. In this study, the sequence impedance model of the sending-end converter (SEC) of VSC-HVDC with the PQ-control outer loop and PLL is derived with the explicit analytic expression, and then, the oscillation mechanism is explored based on the intuitive analysis of the system impedance frequency characteristics. Compared with the subsynchronous oscillation (SSO) caused by the DFIG or power inverter, the theoretical analysis shows that this medium-frequency oscillation (MFO) mainly originates from the SEC due to its negative damping effect between about 100 and 200 Hz. In addition, the impact of the system controller parameters and operating conditions of the DFIG, local grid, and SEC on the oscillation characteristics is analyzed in detail. Finally, the correctness of the theoretical analysis is validated by time-domain simulation.

show abstract

Section: Impedance Model Of the Local Gridmentioning

confidence: 99%

Impedance Modeling and Analysis of Medium-Frequency Oscillation Caused by VSC-HVDC Connected to Local Weak Grid and DFIG-Based Wind Farms

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Numerous research reveals that the equation of the impedance model would become more complicated if more complex control loops are involved in the controller (e.g., the research in [59] and [60]). Reference [61] provides an iterative approach to determine the impedance model at given frequency points, which can eliminate some complicated derivations, but it increases the computational burden.…”

Section: A Aprinciple Of Impedance Modeling Of Power Electronic Convmentioning

confidence: 99%

“…The second technique of dimension-reduction is to consider the average value of the d-axis impedance and q-axis impedance in dq frame as the dimension-reduced lumped impedance model [61], [62], [65], and the specific equations are presented in (18)- (20). However, this technique is lack of a deep theoretical support.…”

Section: B R-x-criterion-based Oscillatory Stability Assessmentmentioning

confidence: 99%

Impedance-Based Oscillatory Stability Analysis of High Power Electronics-Penetrated Power Systems—A Survey

Zhou

et al. 2019

IEEE Access

View full text Add to dashboard Cite

With increasing power electronics integrated into the power grids, the new types of oscillation issues have posed a critical threat to the secure operation of power grids. Apart from the conventional eigenvalue-based analysis, the impedance-based analysis becomes more attractive for the assessment of the oscillatory stability. This paper presents a systematic survey on the technical matters of the emerging impedance-based oscillatory stability analysis of power systems with high power electronics penetration. Firstly, the detailed derivation of impedance models of the power electronic converter-connected equipment are discussed. Then, common coordinate systems for the derivation of impedance models, as well as the characteristics of the impedance model in different coordinate systems are surveyed. On this basis, the aggregation of the individual impedance models is introduced to derive the lumped impedance model. Additionally, two typical impedance-based oscillatory stability criteria are demonstrated and discussed in details. Finally, the advantages as well as the limitations of the impedance-based oscillatory stability analysis, and the contributions as well as the challenges of the existing studies are summarized. A list of relevant literature is accommodated in the end.

show abstract