Matching Analysis of LVRT Grid Code and Injection Current Dependent Voltage Response of WTC Connected to High Impedance AC Grid

Hu, Qi; Ji, Feng; Zhang, Yan; Fu, Lijun

doi:10.1109/tec.2022.3169394

Cited by 10 publications

(5 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Then, considering that reactive current injection takes priority, and the remaining capacity is utilized for active current, the relationships can be Based on (5), there exists an inequality constraint of residual grid voltage, current references, and grid impedance, which is the precondition of the existence of PLL's equilibrium point [31] as represented by ( 16): R eq I q + X eq I d = U eq sin δ (16) where U eq is the equivalent grid impedance, namely the amplitude of U eq . Since −1 ≤ sinδ ≤ 1, (17) can be further derived into [34]:…”

Section: Feasible Current Region Of Gscmentioning

confidence: 99%

Grid-Impedance-Based Transient Current Control for Offshore Wind Turbines under Low-Voltage Fault

Yang,

Gao,

Cao

et al. 2024

JMSE

View full text Add to dashboard Cite

In order to enhance the transient stability of offshore wind turbines (OWTs) in marine energy systems, the grid codes stipulate that OWTs should possess the low-voltage ride-through (LVRT) ability of being grid-tied and injecting reactive current during grid fault. However, the grid-side converter (GSC) of OWTs may lose stability under weak grid or severe fault conditions due to inaccurate current references. To address this issue, a novel transient current control method is proposed to improve the transient stability of permanent-magnet-synchronous-generator (PMSG)-based OWTs. The feature of DC-link overvoltage is investigated and is alleviated by utilizing the GSC’s overcurrent capacity and chopper. Additionally, the equivalent circuit of the PMSG-based OWT connected to the onshore grid is derived based on Thevenin’s theorem. The feasible current region (FCR) is then determined, taking into account the GSC capacity, pre-fault power ability, LVRT requirement, and synchronization stability. Furthermore, a grid-impedance-based transient current control method is designed to enhance the fault ride-through performance and mitigate power oscillation of the OWT under various transient grid impedance and fault conditions. Finally, a simulation model is conducted using PSCAD v4.6.3 software to validate the effectiveness of the proposed method.

show abstract

Section: Feasible Current Region Of Gscmentioning

confidence: 99%

Grid-Impedance-Based Transient Current Control for Offshore Wind Turbines under Low-Voltage Fault

Yang,

Gao,

Cao

et al. 2024

JMSE

View full text Add to dashboard Cite

show abstract

“…From (10) it can be seen that the memory unit c tÀ1 can obtain the s t through the screening of the forgetting gate, input gate and output gate as (11).…”

Section: Lstm Neural Networkmentioning

confidence: 99%

“…The voltage and frequency fluctuations caused by the high voltage ride‐though (HVRT) and low voltage ride‐though (LVRT) due to grid faults become more frequent and hazardous. Both simulation studies using commercial software and hardware‐in‐the‐loop platforms have demonstrated such adverse effects on the power system 10–12 …”

Section: Introductionmentioning

confidence: 99%

“…Both simulation studies using commercial software and hardware-in-the-loop platforms have demonstrated such adverse effects on the power system. [10][11][12] To the best of the authors' knowledge, studies on state estimation related to HVRT and LVRT are rarely reported. However, previous studies on state prediction of a power system with transient faults can provide helpful insights into this topic.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Enhanced dynamic state estimation of regional new energy power system under different abnormal scenarios

Li,

Jiang,

Cui

et al. 2024

Int J Numerical Modelling

View full text Add to dashboard Cite

The high proportion of renewable energy sources in the power grid increases the failure probability of the system, which becomes a new challenge for the safe and stable operation of the regional power grid. To ensure stable control of the power network with substantial renewable energy integration, this article proposes a new method that combines the long short‐term memory (LSTM) neural networks and adaptive cubature Kalman filter (ACKF) to improve the prediction accuracy of mutation data inherited from the renewable generation. Four abnormal scenarios, including low voltage ride‐through (LVRT), high voltage ride‐through (HVRT), continuous fault ride‐through and bad data injection of the regional power grid are investigated through extensive case studies. The proposed method is implemented on the IEEE 30‐node system for performance verification. The simulation results demonstrate that the proposed method has considerably higher robustness than the traditional Kalman filter algorithm and can effectively improve the overall state estimation accuracy of the renewable energy power system under different scenarios.

show abstract

“…Hence, these factors necessitate consideration when evaluating the grid-connected capacity of wind power [24]. Particularly, when integrating a large-scale wind power system into the delivery side, fault overvoltage characteristics emerge from the interaction between the transient properties of the DC system and the LVRT characteristics of the wind farm [25].…”

Section: Introductionmentioning

confidence: 99%

Calculation Method of DC Fault Overvoltage Peak Value for Multi-Send HVDC Systems with Wind Power

Li,

Liu,

Han

et al. 2023

Electronics

View full text Add to dashboard Cite

Commutation failure (CF) and DC blocking (DCB) faults are common occurrences in high-voltage direct current (HVDC) systems, and their impact on the power grid can be significant due to sudden power fluctuations. These issues pose particular challenges in multi-send HVDC systems due to the intricate interaction between AC and DC components. To tackle these challenges, this paper proposes a method for analyzing the peak overvoltage at the converter bus resulting from DC faults in multi-send HVDC systems. The proposed method comprehensively considers the influence of DC/DC coupling and wind turbine low-voltage ride through (LVRT) characteristics on overvoltage. It offers a straightforward approach to calculate the peak overvoltage following a DC fault without the need for complex modeling or dynamic simulation software. By leveraging the equivalent parameters of the AC system and operational parameters of the DC system, the method effectively quantifies the overvoltage. The primary objective of this study is to address multi-send HVDC systems and establish computational formulas that enable a quantitative assessment of transient overvoltage resulting from DC faults. The analysis explores several influencing factors, uncovering that fault-induced overvoltage is influenced by aspects such as system strength and wind turbine reactive power dynamics. In a single-send HVDC system, the level of overvoltage in the system is primarily affected by the short-circuit ratio. A higher short-circuit ratio results in a lower overvoltage level. On the other hand, in multi-send HVDC systems, the overvoltage level is determined by the equivalent impedance of the individual systems. In DC systems where turbines are present in the DC near zone, the overvoltage level at the converter bus is influenced by the power characteristics of the turbines during the LVRT. To validate the accuracy of the proposed method, a comprehensive verification process is conducted. Through this research, the paper aims to contribute to the understanding and management of transient overvoltage in multi-send HVDC systems. By considering relevant factors and employing an equivalent model, the proposed method offers a practical approach for assessing overvoltage and facilitating the design and operation of such systems.

show abstract

Matching Analysis of LVRT Grid Code and Injection Current Dependent Voltage Response of WTC Connected to High Impedance AC Grid

Cited by 10 publications

References 4 publications

Grid-Impedance-Based Transient Current Control for Offshore Wind Turbines under Low-Voltage Fault

Grid-Impedance-Based Transient Current Control for Offshore Wind Turbines under Low-Voltage Fault

Enhanced dynamic state estimation of regional new energy power system under different abnormal scenarios

Calculation Method of DC Fault Overvoltage Peak Value for Multi-Send HVDC Systems with Wind Power

Contact Info

Product

Resources

About