Complete Set of Arc Suppression Coil Equipment
The complete set of arc suppression coil equipment is a compensation device used for low current grounding systems. Its main function is to compensate for the grounding capacitance current by generating inductive current when a single-phase grounding fault occurs in the system, so that the current passing through the grounding point is lower than the current value required to maintain the arc, thereby eliminating the grounding point arc.. We can provide quotations and technical support for the complete set of arc suppression coil equipment.
Application scenarios of the complete set of arc suppression coil equipment:
The complete set of arc suppression coil equipment is widely used in low current grounding systems, such as transmission lines, transformers, and generators. It can operate normally without current passing through the system, but respond quickly in the event of a single-phase ground fault, compensating for the capacitor current and reducing the fault current to a level insufficient to maintain the arc, thereby quickly eliminating the ground fault without causing overvoltage.
The complete set of arc suppression coil equipment is a compensation device used for low current grounding systems. When a single-phase grounding fault occurs in the system, the arc suppression coil generates inductive current to compensate for the grounding capacitance current, making the current passing through the grounding point lower than the current value required to generate intermittent arcs or maintain stable arcs, thus eliminating the grounding point arc. Shanghai Zhiyou Company specializes in producing various voltage levels of arc suppression coils, grounding resistor cabinets, and gap protection devices for transformer neutral point grounding protection.
1、 The working principle of the complete set of arc suppression coil equipment
The complete set of arc suppression coil equipment is a type of arc suppression reactor component used in high-voltage switch circuit breakers. Its function is to withstand the electrical energy of the circuit breaker when it breaks the circuit, convert the electrical energy into magnetic field energy, and thus eliminate the arc. The design and use of a complete set of arc suppression coil equipment and other arc suppression reactor components can effectively prevent arc generation and prolong the circuit breaking time.
When a single-phase grounding fault occurs in the system, the inductive current generated by the arc suppression coil and the capacitive current cancel each other out, reducing the current at the fault point to below 10A, which is beneficial for preventing reignition of arc light after zero crossing, achieving the purpose of arc suppression, reducing the probability of high amplitude overvoltage, and preventing the accident from further expanding. The correct tuning of the arc suppression coil can not only reduce the probability of arc grounding overvoltage, but also effectively suppress the amplitude of overvoltage, reduce the thermal damage effect at the fault point and the voltage of the grounding grid.
2、 Application of complete set of arc suppression coil equipment in power system
The main application of the complete set of arc suppression coil equipment in the power system is to protect the power system and equipment in high-voltage switches and circuit breakers. In high-voltage switches and circuit breakers, strong arcing phenomena are often generated due to the effects of high voltage and high current, which not only damages the switches and circuit breakers, but also poses a threat to the safety of the entire power system. Therefore, installing a complete set of arc suppression coils can effectively curb arc generation, protect the normal operation of equipment and power systems.
In addition, the complete set of arc suppression coils can also be used in DC systems to protect transformers and capacitors. In a DC system, since the current is always unidirectional, if effective measures are not taken during the circuit breaking process, serious arcing phenomena can occur, leading to system damage and safety issues. Installing a complete set of arc suppression coil equipment can effectively curb the occurrence of this phenomenon and maintain the normal operation of the system.
3、 Summary
The complete set of arc suppression coil equipment is an important power equipment in the power system, used to eliminate arcs in high-voltage switches and circuit breakers, protect equipment and ensure the normal operation of the power system. Its working principle is to convert circuit electrical energy into magnetic field energy and eliminate arc phenomena. In the power system, the proper installation and use of complete sets of arc suppression coils can effectively ensure the safe operation of the power system and the normal operation of equipment.
The complete set of arc suppression coil equipment mainly consists of the following parts:
The function of a grounding transformer is to lead out the neutral point for adding an arc suppression coil when the system is connected in a delta or Y-shaped configuration. This transformer adopts a Z-type connection (also known as a zigzag connection), which is different from ordinary transformers in that each phase coil is wound on two magnetic columns. The advantage of this connection is that the zero sequence magnetic flux can flow along the magnetic columns, while the zero sequence magnetic flux of ordinary transformers flows along the leakage magnetic circuit. Therefore, the zero sequence impedance of a Z-type grounding transformer is very small (about 10 Ω), while that of ordinary transformers is much larger. Therefore, the regulations stipulate that when using ordinary transformers with arc suppression coils, their capacity should not exceed 20% of the transformer capacity, while Z-type transformers can be equipped with 90% to 100% capacity arc suppression coils. Grounding transformers can also be equipped with secondary loads in addition to arc suppression coils, which can replace the transformers used and save investment costs.
(1) The current regulation methods of arc suppression coils are generally divided into three types, namely: adjusting the air gap of the iron core, adjusting the excitation of the iron core, and adjusting the turns of the arc suppression coil. At present, most of the arc suppression coils in operation in the system are of the adjustable turn type. They extract several tap changers according to different turns of the winding, switch the original non excited tap changer to an on load tap changer, change the number of turns connected, and thus change the inductance. The current regulation range of the arc suppression coil is 30-100% of the rated current. The current between adjacent tap changers is arranged in equal steps, and the number of tap changers is determined by the current difference between adjacent tap changers being less than 5A. In order to reduce residual current, the number of splitters has been increased. Depending on the capacity, there are currently 9-14 levels, making it reliable and ensuring safe operation. The arc suppression coil is also equipped with an external voltage transformer and a current transformer.
(2) The compensation methods for arc suppression coils are generally divided into three types: overcompensation, undercompensation, and minimum residual current.
In the automatic tracking arc suppression coil, due to high adjustment accuracy and small residual current, it operates close to the resonance (full compensation) point. To prevent resonance overvoltage and adapt to various operating modes, a damping resistor box should be connected in series in the grounding circuit of the arc suppression coil. In this way, even in the fully compensated state during operation, resonance is avoided due to the damping effect of the resistor, and the neutral point voltage will not exceed 15% of the phase voltage, meeting the regulatory requirements, allowing the arc suppression coil to operate in either over compensated, fully compensated, or under compensated mode. Damping resistors can be selected as sheet resistors, with different resistance values depending on the capacity. When a single-phase grounding occurs in the system, a large current flows through the neutral point, and the damping resistor must be short circuited with voltage and current dual protection.
The automatic tuning and line selection device is a key part of the entire technology, and all calculations and controls are implemented by it. The controller measures the capacitance current of the system to ground in real time, and calculates the current detuning degree ε of the power grid. When the detuning degree deviation exceeds the predetermined range, the on load switch is driven through the control circuit interface to adjust the arc suppression coil tap until the detuning degree and residual current are within the predetermined range. When a single-phase grounding occurs in the system, the zero sequence voltage and zero sequence current of each circuit at the PT secondary open triangle of the system are collected for analysis and processing. Line selection algorithms such as apparent power, zero sequence impedance changes, harmonic changes, and fifth harmonic are used to select the line.
Before installing the arc suppression coil on the isolation switch, it is used to switch the arc suppression coil. Due to the voltage transformer inside the arc suppression coil not meeting the measurement accuracy, a neutral point voltage transformer needs to be installed separately to measure the neutral point voltage.
Ordering Notice:
We are willing to serve you with our professionalism, sincerity, and integrity.
