In China's 6 ~ 35KV neutral point ungrounded power grid, electromagnetic voltage transformer (hereinafter referred to as PT) has two related problems to be solved:
(1) The overvoltage generated by PT ferromagnetic resonance often causes insulation breakdown and external insulation discharge in the equipment, and often causes large-scale power outage due to untimely accident handling or accident expansion.
(2) The arc grounding in the power grid causes the PT to be burned frequently.
The use of SMR-LXQ primary resonance elimination device can play the following four aspects, effectively solving the above problems: (1) eliminating or damping PT ferromagnetic resonance overvoltage; (2) effectively suppressing the flow of intermittent arc grounding Overcurrent of PT winding prevents PT from burning; (3) Limits inrush current generated in PT primary winding loop when system single phase ground disappears, prevents PT fuse from being blown; (4) Longer after system single phase grounding Time protects the PT from damage.
The structural design of the SMR-LXQ primary resonance elimination device of our company has been greatly improved from the improvement of the heat capacity of the harmonic elimination device. The harmonic elimination device adopts SiC with excellent electrical properties and ultrafine particles as a base material, and is pressed into a high-density, round cake-like body by a large-tonnage press, and is sintered at a high temperature of thousands of degrees in a reducing atmosphere. . The surface structure of the exposed resistor is specially treated to withstand the sun and rain, and can be directly used indoors and outdoors. It is small in size, light in weight, fast in heat dissipation, high in strength and easy to install.