What Is a DC Reactor?
Among reactors, which are also inductance devices, a DC reactor is a coil used to insert reactance into the smoothing circuit after the inverter converter.
Specifically, a DC reactor is often used to improve the power factor and suppress harmonics. It is recommended by manufacturers for installation when the power supply capacity is large, ranging from several KV to several 100KV, or more than 10 times the inverter capacity.
Uses of DC Reactors
In addition to power factor improvement and harmonic suppression, DC reactors are also used to secure the impedance of the power supply line. Power supply line applications are also known as choke coils. DC reactors are often used together with AC reactors, and in this case, a further harmonic suppression effect can be expected.
In actual products, inverter circuits are used in a wide range of applications such as air conditioning equipment and motors. It can be said that inverters are indispensable, especially in high currents. There is also the implication of smoothing the ripple that occurs in the converter circuit from AC to DC.
Principle of DC Reactors
In an inverter circuit, a phase adjustment element called a phase advance capacitor (SC) is usually inserted to adjust the load phase. Although this capacitor is highly effective in improving the power factor, it has the side effect of increasing harmonic components and requires a reactance element to adjust the harmonic impedance of the circuit.
This harmonic suppression is necessary to maintain the quality of the commercial power supply. Specified customers are those who receive power at special high voltage (voltage exceeding 7KV) and high voltage (AC voltage between 0.6KV and 7KV) to which guidelines apply, and most offices and buildings fall under this category.
However, the structure of a reactor is typically a wound coil, with various types available such as oil-filled self-cooling types and those using an iron core.