Hybrid Arc Suppression & Grounding System
1. Scope of application
Hybrid Arc Suppression & Grounding System is a key device for neutral point grounding protection in power system. It consists of grounding transformer, arc extinguishing coil, damping resistor, control unit and matching switch, etc. It can achieve rapid arc extinguishing and overvoltage suppression by dynamically compensating the capacitive current generated by single-phase grounding fault. The core functions include:
Dynamic compensation: adopt pre-adjustment or automatic tracking technology to monitor the grid capacitance current in real time and adjust the inductance of arc extinguishing coil to achieve 10μs level fast response.
Arc suppression: offset the capacitive current of the fault point through inductive current, so that the grounding arc cannot be maintained and extinguishes itself, reducing the risk of fire and insulation breakdown.
System compatibility: adapt to 6~66kV neutral point ungrounded or grounded by arc extinguishing coil distribution network, support cable and overhead line hybrid system.
2. Operation environment
1) Altitude: ≤1000 meters.
2) Ambient temperature: Maximum +40oC, Minimum -40oC.
3) Max outdoor wind speed: ≤45m/s.
4) Max Ground ramp degree: ≤3°.
5) Seismic level: ≤3m/s2 at horizontal direction and ≤1.5m/s2 at vertical direction.
6) Installation environment: No obvious and heavy pollution, no explosive and corrosive gas and dust, with good air ventilation and no severe vibration and shock.
7) If the application environment is different from the above standard conditions, please contact for customized designs.
3. Product advantages
1) Efficient arc extinguishing and fault suppression
Use pre-regulation technology (such as turn-adjusting type and capacitance-adjusting type) to achieve "zero response time" compensation, reducing the probability of single-phase grounding fault developing into permanent fault by more than 50%.
2) Intelligent control
Integrated microcomputer automatic tracking system, real-time adjustment of compensation gear through zero-sequence voltage and current dual signals, support remote monitoring and MODBUS/IEC61850 communication protocol.
3) Flexible compensation mode
Support over-compensation, under-compensation and full compensation modes, give priority to over-compensation (inductor current> capacitor current 5%~10%) to avoid resonance risk and adapt to the needs of grid expansion.
4) High reliability design
Equipped with multiple protection mechanisms such as thyristor self-triggering protection and gear lock to ensure primary/secondary system isolation and continuous operation in case of fault. 5) Overvoltage suppression capability
Through the coordinated action of damping resistors and arc suppression coils, overvoltage phenomena such as ferromagnetic resonance and frequency division resonance are eliminated, and transient overvoltage is limited to less than 2.5 times the phase voltage.
6) Economic advantages
Reduce the insulation level requirements of the power grid and reduce the equipment investment cost by 10%~20%, which is suitable for the transformation of old power grids and the expansion of new energy systems.
4. Applications
1) Power system
Used for single-phase grounding fault processing in 6-66kV distribution networks, especially for cable-intensive urban power grids with capacitive currents >10A.
2) Rail transit power supply
Quickly cut off overload or short-circuit current in the DC circuit breaker of the train traction system to protect railway equipment from arc damage.
3) Industrial automation
Used in high-voltage distribution systems of chemical, metallurgical and other enterprises to prevent arc faults caused by equipment overload or cable aging.
4) New energy field
Balance capacitive current in photovoltaic power stations and wind farms to solve the problem of excessive grounding current caused by distributed power supply access.
5) Urban distribution network transformation
For the upgrading of power grids in old urban areas, dynamic compensation technology is used to improve power supply reliability and reduce the incidence of power outages.
Hybrid Arc Suppression & Grounding System is based on dynamic compensation, and has intelligent control, multiple protections and strong compatibility. It effectively suppresses arc faults and overvoltage in power systems, rail transit, new energy and other fields, and is a key device for improving the safety and economy of power grids
