Double closed loop PI control with full compensation arc elimination based on zero sequence voltage of neutral point

Area of Science:

• Electrical Engineering
• Power Systems Analysis
• Fault Detection and Mitigation

Background:

• Grounding faults in power systems generate zero-sequence voltage due to unbalanced parameters, negatively impacting arc suppression.
• Existing arc suppression methods struggle with the effects of unbalanced parameters under various grounding modes.
• Controllable voltage sources offer potential for improved arc suppression but require precise control strategies.

Purpose of the Study:

• To analyze the influence of ground unbalance parameters on arc suppression effectiveness.
• To reveal the mechanism of full compensation arc suppression using neutral point zero-sequence voltage.
• To develop and validate a novel control model for enhanced arc suppression during grounding faults.

Main Methods:

• Analysis of ground unbalance parameters and their effect on controllable voltage source arc suppression.
• Development of a fully compensated arc suppression model using a dual closed-loop Proportional-Integral (PI) controller.
• Implementation of control strategies based on neutral point voltage deviation and fault phase residual voltage.

Main Results:

• The dual closed-loop PI control algorithm effectively stabilizes the controllable voltage source output waveform.
• Residual voltage stabilization times were significantly improved compared to traditional methods, ranging from 43 ms to 2.4 s.
• The proposed method consistently reduced residual voltage in the grounded fault phase to below 10 V, ensuring reliable arc extinction.

Conclusions:

• The developed dual closed-loop PI control method offers a robust solution for arc suppression in grounding faults.
• This approach enhances the stability and reliability of power systems by ensuring effective arc extinction.
• Simulation and low-voltage tests confirm the algorithm's feasibility and effectiveness.