scholarly journals DC Voltage Adaptive Droop Control Strategy for a Hybrid Multi-Terminal HVDC System

Energies ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 380 ◽  
Author(s):  
Yingpei Liu ◽  
La Zhang ◽  
Haiping Liang
Keyword(s):  
High Voltage ◽  
Direct Current ◽  
Control Strategy ◽  
Power Flow ◽  
Influence Factor ◽  
Current System ◽  
Droop Control ◽  
Dc Voltage ◽  
Hvdc System ◽  
High Voltage Direct Current

To solve the problems of DC voltage control and power allocation in the hybrid multi-terminal high voltage direct current system effectively, a DC voltage adaptive droop control strategy based on DC voltage-current characteristics is proposed. Based on adjustment of the droop coefficient of the converter station, the proposed control strategy introduces the influence factor of the droop coefficient, which considers the dynamic power margin of the converter station according to the direction of DC current variation in the converter station. When changes in the hybrid multi-terminal high voltage direct current system power flow occur, the droop coefficient of the converter station can be adjusted by the influence factor of the droop coefficient, so that the converter station can participate in power regulation according to its own power regulating ability. Consequently, the proposed control strategy can reasonably allocate the active power and minimize the deviation of the DC voltage. Besides, the stability analysis of the proposed control strategy is also carried out. Simulation results have verified the feasibility and effectiveness of the proposed control strategy.

Research on DC Voltage Control Strategies for Typical Four-Terminal HVDC System

2014 ◽  
Vol 521 ◽  
pp. 222-228
Author(s):  
Kai Wang ◽  
Hai Shun Sun ◽  
Yu Hua ◽  
Yuan Liu ◽  
Wei Xing Lin ◽  
...  
Keyword(s):  
High Voltage ◽  
Direct Current ◽  
Control Strategy ◽  
Alternative Energy ◽  
Control Strategies ◽  
Future Trend ◽  
Voltage Source ◽  
Voltage Source Converter ◽  
Dc Voltage ◽  
High Voltage Direct Current

The continuous development of alternative energy has put forward higher requirement for electricity transmission. To cope with its fluctuation characteristics, high voltage direct current (HVDC) technology has received more attention. Voltage Source Converter (VSC) based Multi-Terminal High Voltage Direct Current (MTDC) represents the future trend of HVDC technology. This paper mainly focuses on the control strategies of a four-terminal VSC based MTDC power transmission system. The operation characteristic of the system was studied, and the proposed two control strategies, master-slave control strategy and DC voltage droop control strategy, were verified through simulations. The latter control strategy was proved to be performing well under various conditions, including converter station disconnection and faults at AC side of the converter.

scholarly journals Failure Rate and Economic Cost Analysis of Clamped-Single Submodule with DC Short Current Protection for High Voltage Direct Current System

Electronics ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 993
Author(s):  
Yun-Gi Kwak ◽  
Feel-Soon Kang ◽  
Sung-Geun Song
Keyword(s):  
Failure Rate ◽  
High Voltage ◽  
Direct Current ◽  
Current System ◽  
Short Circuit ◽  
Fault Tree ◽  
Economic Cost ◽  
Hvdc System ◽  
High Voltage Direct Current ◽  
Circuit Components

Clamped-single submodule (CSSM) has DC short circuit current protection function to improve the safety and stability of high voltage, direct current (HVDC) system. In order to carry out the protection, it needs an additional number of insulated gate bipolar transistors (IGBTs) and diodes compared to the conventional half-bridge submodule (HBSM). In general, the failure rate tends to increase in proportion to the number of circuit components. Also, complex operation of the submodule may increase the failure rate, so accurate reliability analysis considering these points is required to apply CSSM in a practical HVDC system. We estimate the failure rate and the mean time between failures (MTBF) of CSSM using a fault tree. Fault-tree analysis (FTA) is possible to analyze the failure rate more accurately than the prior part count failure analysis (PCA) that considers only the number of parts, the type of parts, and the connection status of each circuit component. To provide guidelines for submodule selection under various conditions, we compare the economic cost of a CSSM with HBSM, FBSM, and clamped-double submodule (CDSM), and analyze the failure rate according to the voltage margin of the parts.

scholarly journals Electromechanical Transient Modeling of Line Commutated Converter-Modular Multilevel Converter-Based Hybrid Multi-Terminal High Voltage Direct Current Transmission Systems

Energies ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 2102 ◽  
Author(s):  
Liang Xiao ◽  
Yan Li ◽  
Huangqing Xiao ◽  
Zheren Zhang ◽  
Zheng Xu
Keyword(s):  
High Voltage ◽  
Direct Current ◽  
Power Flow ◽  
Large Scale ◽  
Transient Stability ◽  
Modular Multilevel Converter ◽  
Multilevel Converter ◽  
Hvdc System ◽  
High Voltage Direct Current ◽  
Current Transmission

A method for electromechanical modeling of line commutated converter (LCC)-modular multilevel converter (MMC)-based hybrid multi-terminal High Voltage Direct Current Transmission (HVDC) systems for large-scale power system transient stability study is proposed. Firstly, the general idea of modeling the LCC-MMC hybrid multi-terminal HVDC system is presented, then the AC-side and DC-side models of the LCC/MMC are established. Different from the conventional first-order DC-side model of the MMC, an improved second-order DC-side model of the MMC is established. Besides considering the firing angle limit of the LCC, a sequential power flow algorithm is proposed for the initialization of LCC-MMC hybrid multi-terminal HVDC system. Lastly, simulations of small scale and large scale power systems embedded with a three-terminal LCC-MMC hybrid HVDC system are performed on the electromechanical simulation platform PSS/E. It is demonstrated that if the firing angle limit is not considered, the accuracy of the power flow solutions will be greatly affected. Steady state calculation and dynamic simulation show that the developed LCC-MMC hybrid MTDC model is accurate enough for electromechanical transient stability studies of large-scale AC/DC system.

scholarly journals Control-Induced Time-Scale Separation for Multiterminal High-Voltage Direct Current Systems Using Droop Control

2020 ◽  
Vol 28 (3) ◽  
pp. 967-983 ◽  
Author(s):  
Yijing Chen ◽  
Miguel Jimenez Carrizosa ◽  
Gilney Damm ◽  
Francoise Lamnabhi-Lagarrigue ◽  
Ming Li ◽  
...  
Keyword(s):  
High Voltage ◽  
Direct Current ◽  
Time Scale ◽  
Droop Control ◽  
Scale Separation ◽  
High Voltage Direct Current ◽  
Time Scale Separation ◽  
Current Systems
Sign in / Sign up

Export Citation Format

Share Document