Damping resistor

Damping resistors are named for their role in the circuit. In order to prevent the loop from oscillating, some circuits use series or parallel resistors in the line to consume some of the energy that can cause oscillation. This resistor is called a damping resistor.

First, the damping resistance

In order to effectively absorb the higher harmonic components of the secondary circuit of the rectifier transformer, the output circuit is prevented from resonating, and the rectifier transformer is effectively protected. A damping resistor must be provided at the output of the rectifier transformer. In any case, it is absolutely not allowed to connect the rectifier transformer output directly to the electric field without a damping resistor.
The electrostatic precipitator rectifier transformer matches the parameter size of the damping resistor. Currently, there is no uniform standard in the country. The rated power of the damping resistor must be greater than the product of its resistance and the square of the secondary rated current, and a certain safety margin must be left.

Second, the damping resistance model

The high-voltage damping resistor is installed between the rectified high-voltage output and the electric field incoming line. It is recommended to be installed on the contact (vertical suspension) of the isolating switch in the high-voltage isolating switch cabinet, or on the through-wall bushing before the electric field. Because the damping resistor works, it will generate heat, so try not to install it on the copper screw of the high voltage output end of the rectification, so as not to affect the life of the sealing rubber ring of the high voltage output end. If it is serious, it will leak oil. Pay attention to the distance from the side shell and other equipment during installation to prevent discharge.
Selection reference
0.1-0.4A rectification becomes 2KΩ/500W (outer drawing Figure 1)
0.6-0.8A rectification becomes 1KΩ/1200W (outer drawing Figure 1)
1.0-1.6A rectification 700Ω/2800W (outer drawing Figure 1)
1.8-2.0A rectification becomes 500Ω/3000W (outer drawing Figure 2).

Third, the selection of damping resistance

The quality of the damping resistor seriously affects the use effect and service life of the high-voltage silicon rectifier transformer of the electrostatic precipitator. The high-voltage silicon rectification power supply produced by our company is made of white corundum porcelain bottle and high-quality electric resistance wire.
Due to the limitation of the high-voltage isolating switch box, in order to prevent high-voltage ignition, the size of the damping resistor can only be within the allowable size range of the high-voltage isolating switch box. Commonly used damping resistors generally have diameters of Φ75 and Φ100, and lengths of L230, L380 and L300. During the use of the damping resistor, the relationship between the high-voltage current will cause the resistance wire to heat up, and the structure of the damping resistor porcelain bottle will inevitably affect the heat dissipation effect. Therefore, the longer the external dimension of the damping resistor, the longer the diameter, the more the diameter and the resistance value. Large, the better the heat dissipation effect, but this needs to be customized according to the actual requirements of the electric dust removal silicon rectifier transformer. Excessive margin is also an unnecessary waste.