Research on stability margin enhancement for low-voltage multi-terminal DC system based on additional damping control

Voltage stability margin is ensured through the reactive power resources. In order to generate the reactive power references and ensure the low-voltage ride-through (LVRT) control of a wind farm system based on squirrel cage induction generator, this paper proposed an optimal control approach based on fractional-order (FO) PI-fuzzy-PI (FOPI-fuzzy-FOPI) controller. The proposed control method ensures, also, the demand for active and reactive power predetermined by the transmission system operator (TSO) and satisfies the grid code recommendations. In order to achieve a faster tracking of state variables of the system, the FO operators are optimized using the particle swarm optimization algorithm (PSOA). Using FO operator and PSOA, the responses of the system can be improved. The proposed controller provides additional parameters for better tracking performance and faster convergence can be achieved. Numerical simulation results are presented to analyze the advantages of the proposed control approach to design a physically, realizable controller. The present results are compared with various control methods to show the superiority of the method proposed in this paper.

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Improving voltage profile of load bus of wind generation system using DSTATCOM

Journal of Energy in Southern Africa ◽

10.17159/2413-3051/2015/v26i4a2114 ◽

2017 ◽

Vol 26 (4) ◽

pp. 81

Author(s):

Manju Aggarwal ◽

Madhusudan Singh ◽

S.K. Gupta

Keyword(s):

Distribution System ◽

Voltage Stability ◽

Reactive Power ◽

Low Voltage ◽

Stability Margin ◽

Wind Generation ◽

Voltage Profile ◽

Generation System ◽

Wind Generation System ◽

The Impact

In a low voltage distribution system with integrated wind plant, voltage stability is impacted by the large variation of load and wind penetration. The compensators like SVC and DSTATCOM are currently being used to address such issue of voltage instability. This paper analyses the impact of wind penetration and variation of active and reactive power of the load on voltage profile of a wind generation system with and without DSTATCOM. It also analyses the performance of the system during fault by calculating various parameters of the system. It has been demonstrated that voltage stability margin increases using DSTATCOM at different wind penetration levels. This system has been simulated and analysed in MATLAB 2011b using a power system toolbox under steady state and transient conditions.

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Analysis of Interactive Behavior and Stability of Low Voltage Multi-terminal DC System Under Droop Control Modes

IEEE Transactions on Industrial Electronics ◽

10.1109/tie.2021.3095803 ◽

2021 ◽

pp. 1-1

Author(s):

Wei Deng ◽

Wei Pei ◽

Qi Wu ◽

Ying Zhuang

Keyword(s):

Low Voltage ◽

Droop Control ◽

Dc System ◽

Interactive Behavior

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Mechanism of the Switching Transient in a Low-Voltage DC System

1985 IEEE International Symposium on Electromagnetic Compatibility ◽

10.1109/isemc.1985.7566910 ◽

1985 ◽

Author(s):

Jilin Shi ◽

R. M. Showers

Keyword(s):

Low Voltage ◽

Dc System

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Weighted average current method for active damping control based on grid voltage feed-forward

Journal of Cloud Computing Advances Systems and Applications ◽

10.1186/s13677-021-00236-8 ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Shengqing Li ◽

Xinluo Li ◽

Xiaobao Lee

Keyword(s):

Control Strategy ◽

Weighted Average ◽

Stability Margin ◽

Current Control ◽

Power Network ◽

Weak Current ◽

Damping Control ◽

Average Current ◽

Grid Connected Inverter ◽

The Stability

AbstractIn the weak current network environment, the existence of power network impedance will reduce the current control stability margin of LCL grid connected inverter, the stability margin will gradually deteriorate as the inductive component of the power network impedance increases, leading to system instability. In this paper, an improved weighted average current control strategy is proposed, which is based on the active damping control of the voltage feedforward of the charged network. In the new control strategy, with the zero-pole cancellation method, a new weighting coefficient related only to the parameters of LCL filter is obtained, which reduces the order of the system, suppresses the influence of power network impedance, and improves the stabilization of the system, getting better inverter output current quality. Then the influence of power network impedance on the control system of grid connected inverter is analyzed, and the feed-forward control of grid voltage is improved to improve the stability of inverter in weak current network. The Bode diagram analysis and MATLAB simulation results proved that the proposed control strategy is feasible.

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