1kHz air-core reactor: Why is it an indispensable short-circuit current "brake" in distribution lines?

As the name suggests, the magnetic flux loop of the air-core reactor is not formed through the iron core, but directly through the air. This design not only reduces the weight of the equipment, but also avoids the problem of unstable inductance value caused by iron core saturation. 1kHz air-core reactors are usually wound by multiple layers of parallel round aluminum wires, and a precise insulation layer is provided between each layer of wires to ensure the reliability of inter-turn insulation. In addition, a heat dissipation air duct is designed inside the reactor, which effectively improves the thermal stability and service life of the equipment through natural convection cooling.

In circuit theory, inductance is an important parameter to describe the resistance of the circuit to alternating current. The larger the inductance value, the stronger the resistance to current. The 1kHz air-core reactor is connected in series in the circuit, using its inductance characteristics to increase the total inductance value of the circuit, thereby resisting alternating current. This feature gives the air-core reactor a unique advantage in limiting short-circuit current.

In the distribution line, when a short-circuit fault occurs, the current will rise sharply, forming a short-circuit current. The magnitude of the short-circuit current depends on factors such as the power supply voltage, circuit impedance, and the location of the fault point. If the short-circuit current is too large, it will cause severe thermal shock and mechanical stress to the power grid equipment, and even cause catastrophic consequences such as fire and explosion.

The 1kHz air-core reactor can respond quickly when a short-circuit fault occurs by being connected in series in the circuit. When the short-circuit current flows through the reactor, the reactor will generate a large induced electromotive force due to the resistance of the inductance to the alternating current. This induced electromotive force is opposite to the power supply voltage, thereby effectively reducing the actual current value in the circuit. As the short-circuit current increases, the induced electromotive force generated by the reactor also increases, and the resistance to the current is also stronger. Therefore, the 1kHz air-core reactor can quickly generate a large induced electromotive force when a short-circuit fault occurs, effectively limiting the magnitude of the short-circuit current and preventing it from causing damage to the power grid equipment.

The 1kHz air-core reactor has a wide range of applications in power systems, not limited to short-circuit current limitation in distribution lines. In the power system, it can also be used for reactive power compensation, filtering, phase shifting and other aspects.

In terms of reactive power compensation, air-core reactors can be used as providers of inductive reactive power and used in parallel with capacitors to form reactive compensation devices. By adjusting the inductance value of the reactor, accurate compensation of reactive power of the power grid can be achieved, the power factor of the power grid can be improved, line losses can be reduced, and the operation efficiency of the power grid can be improved.

In terms of filtering, air-core reactors can be used in series with capacitors to form filters. The filter can filter out the harmonic components in the power system, improve the quality of electric energy, and protect the power grid equipment from harmonic interference.

In terms of phase shifting, by adjusting the inductance value of the air-core reactor, the phase relationship between current and voltage can be changed to achieve the phase shifting function. This function has a wide range of application value in power system flow control, reactive power distribution and other aspects.

The reason why 1kHz air-core reactors can be widely used in power systems is inseparable from their unique advantages.

The air-core reactor adopts a coreless design to avoid the problem of unstable inductance value caused by core saturation. This makes the inductance value of the reactor more stable and the blocking effect on the current more reliable.

The air-core reactor is wound with multiple layers of parallel round aluminum wires, and a precise insulation layer is provided between each layer of wires to ensure the reliability of the inter-turn insulation. At the same time, the reactor is designed with a heat dissipation airway, which improves the thermal stability and service life of the equipment through natural convection cooling.

The air-core reactor also has the advantages of small size, light weight and easy maintenance. This makes the reactor more convenient during installation, commissioning and maintenance, and reduces the operating cost of the power grid.