scholarly journals The Complex Torque Coefficient Applied in Subsynchronous Oscillation Caused by HVDC

2019 ◽  
Vol 533 ◽  
pp. 012004
Author(s):  
Hanhua Zhang ◽  
Jiaqi Li ◽  
Jun Wen ◽  
Shuang Zhang ◽  
Bei Tian
Keyword(s):  
Subsynchronous Oscillation ◽  
Torque Coefficient

The Comparative Analysis of SVC and STATCOM on Subsynchronous Oscillation Mitigation

2013 ◽  
Vol 756-759 ◽  
pp. 245-249 ◽  
Author(s):  
Jian Zhang ◽  
Xiang Ning Xiao ◽  
Ben Feng Gao ◽  
Chao Luo
Keyword(s):  
Short Circuit ◽  
Time Domain Simulation ◽  
Subsynchronous Oscillation ◽  
Damping Coefficients ◽  
Torque Coefficient ◽  
Electrical Damping ◽  
The Time Domain ◽  
Generator Terminal ◽  
Short Circuit Fault ◽  
Signal Method

The methods for subsynchronous oscillation mitigation based on SVC and STATCOM are analyzed in this paper. According to the IEEE first benchmark model, the electrical damping coefficients respectively provided by SVC and STATCOM connected at the generator terminal, as well as positive damping condition, are deduced by complex torque coefficient approach. Correlative factors which influence the two positive dampings are compared. The analysis results indicate that the positive damping provided by SVC is proportional to the size of system voltage. The positive damping provided by STATCOM is not affected by the size of system voltage, which is mostly proportional to the subsynchronous voltage produced itself. The controllers of SVC and STATCOM are designed and the positive dampings separately offered by SVC and STATCOM are optimized by phase compensation with test signal method. The time domain simulation reveals that STATCOM has stronger damping ability than SVC in the case of short circuit fault.

Damping Analysis of Subsynchronous Oscillation Caused by HVDC

2013 ◽  
Vol 732-733 ◽  
pp. 1065-1068
Author(s):  
Shi Wu Xiao ◽  
Lan Lan Shu
Keyword(s):  
Time Domain ◽  
Test Signal ◽  
Subsynchronous Oscillation ◽  
High Voltage Direct Current ◽  
Damping Characteristics ◽  
Torque Coefficient ◽  
Machine Systems ◽  
Electrical Damping ◽  
The Time Domain ◽  
Signal Method

High Voltage Direct Current transmission (HVDC) will cause torsional interaction under certain conditions. Among a variety of factors, improper rectifier control has fateful effect. In the paper, the test signal method which is the time-domain form of the complex torque coefficient approach (CTC approach) is studied. Its application conditions in multi-machine systems are summarized. Using the test signal method, impacts of DC power, DC voltage, rectifier controller parameters and generator output on electrical damping characteristics in the Suizhong system are studied based on time-domain simulation model.

Overview of Subsynchronous Oscillation in Grid-connected Wind Farm

2020 ◽  
Vol 13 (7) ◽  
pp. 969-979
Author(s):  
Xu Pei-Zhen ◽  
Lu Yong-Geng ◽  
Cao Xi-Min
Keyword(s):  
Power Systems ◽  
Wind Turbine ◽  
Large Scale ◽  
Wind Farm ◽  
Wind Farms ◽  
Induction Generator ◽  
Future Research ◽  
Stable Operation ◽  
Subsynchronous Oscillation ◽  
Different Types

Background: Over the past few years, the subsynchronous oscillation (SSO) caused by the grid-connected wind farm had a bad influence on the stable operation of the system and has now become a bottleneck factor restricting the efficient utilization of wind power. How to mitigate and suppress the phenomenon of SSO of wind farms has become the focus of power system research. Methods: This paper first analyzes the SSO of different types of wind turbines, including squirrelcage induction generator based wind turbine (SCIG-WT), permanent magnet synchronous generator- based wind turbine (PMSG-WT), and doubly-fed induction generator based wind turbine (DFIG-WT). Then, the mechanisms of different types of SSO are proposed with the aim to better understand SSO in large-scale wind integrated power systems, and the main analytical methods suitable for studying the SSO of wind farms are summarized. Results: On the basis of results, using additional damping control suppression methods to solve SSO caused by the flexible power transmission devices and the wind turbine converter is recommended. Conclusion: The current development direction of the SSO of large-scale wind farm grid-connected systems is summarized and the current challenges and recommendations for future research and development are discussed.

scholarly journals CFD Simulation for Estimating Efficiency of PBCF Installed on a 176K Bulk Carrier under Both POW and Self-Propulsion Conditions

Processes ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 1192
Author(s):  
Dong-Hyun Kim ◽  
Jong-Chun Park ◽  
Gyu-Mok Jeon ◽  
Myung-Soo Shin
Keyword(s):  
Cfd Simulation ◽  
Open Water ◽  
Navier Stokes ◽  
Water Efficiency ◽  
Ocean Engineering ◽  
Bulk Carrier ◽  
Incompressible Viscous Flow ◽  
Korea Research Institute ◽  
Torque Coefficient ◽  
Viscous Flow Field

In this paper, the efficiency of Propeller Boss Cap Fins (PBCF) installed at the bulk carrier was estimated under both Propeller Open Water (POW) and self-propulsion conditions. For this estimation, virtual model-basin tests (resistance, POW, and self-propulsion tests) were conducted through Computational Fluid Dynamics (CFDs) simulation. In the resistance test, the total resistance and the wake distribution according to ship speed were investigated. In the POW test, changes of thrust, torque coefficient, and open water efficiency on the propeller according to PBCF installation were investigated. Finally, the International Towing Tank Conference (ITTC) 1978 method was used to predict the effect of PBCF installation on self-propulsive coefficient and brake horsepower. For analyzing incompressible viscous flow field, the Reynolds-Averaged Navier–Stokes (RANS) equation with SST k-ω turbulence model was calculated using Star-CCM+ 11.06.010-R8. All simulation results were validated by comparing the results of model tests conducted at the Korea Research Institute of Ships and Ocean Engineering (KRISO). Consequently, for the self-propulsion test with the PBCF, a 1.5% reduction of brake horsepower was estimated in the simulation and a 0.5% reduction of the brake horsepower was estimated in the experiment.

Study of HVDC System and Subsynchronous Oscillation

2015 ◽  
Vol 1092-1093 ◽  
pp. 356-361
Author(s):  
Peng Fei Zhang ◽  
Lian Guang Liu
Keyword(s):  
Power Plant ◽  
Time Domain ◽  
Simulation Method ◽  
Time Domain Simulation ◽  
Stable Convergence ◽  
Turbine Generator ◽  
Plant Model ◽  
Subsynchronous Oscillation ◽  
Hvdc System ◽  
Simulation Results

With the application and development of Power Electronics, HVDC is applied more widely China. However, HVDC system has the possibilities to cause subsynchronous torsional vibration interaction with turbine generator shaft mechanical system. This paper simply introduces the mechanism, analytical methods and suppression measures of subsynchronous oscillation. Then it establishes a power plant model in islanding model using PSCAD, and analyzes the effects of the number and output of generators to SSO, and verifies the effect of SEDC and SSDC using time-domain simulation method. Simulation results show that the more number and output of generators is detrimental to the stable convergence of subsynchronous oscillation, and SEDC、SSDC can restrain unstable SSO, avoid divergence of SSO, ensure the generators and system operate safely and stably

scholarly journals Subsynchronous Oscillation and Advanced Analysis: A Review

IEEE Access ◽  
2020 ◽  
Vol 8 ◽  
pp. 224020-224032
Author(s):  
Robin Noel Damas ◽  
Yongju Son ◽  
Myungseok Yoon ◽  
Sung-Yul Kim ◽  
Sungyun Choi
Keyword(s):  
Subsynchronous Oscillation ◽  
Advanced Analysis
Sign in / Sign up

Export Citation Format

Share Document