What is a Switchgear?
Switchgear is not only a very important element but also an essential part in electric power system. It is the combination of electrical disconnect switches, circuit breakers and fuses used to protect, isolate and control electrical equipment. People use it for both to clear faults downstream and to de-energize equipment to allow to do work. We know that this type of equipment is directly linked to the reliability of the electricity supply.
Central power stations of early time used simple open knife switches, those generally mounted on insulating panels of marble or asbestos. Making opening manually operated switches too dangerous for anything other than isolation because power levels and voltages rapidly escalated of a de-energized circuit. And also, oil-filled equipment allow arc energy to contain along with safely control.
Switchgear generally that means sostly line-up would be a metal-enclosed structure with electrically operated switching elements up to 20th century that used oil circuit breakers. Now today in modern days, oil-filled equipment has modified and largely been replaced by vacuum, SF6 or air-blast equipment. Automatic equipment allow large currents along with power levels to control safely.
LT and HT Switching Equipment
However, scientists invented high-voltage switchgear at the last part of the 19th century for operating motors as well as other electric machines. Over time with the improving technology, now we can use it of voltages up to 3300 kV.
In substations, these things are located on both the high-voltage and low-voltage sides of large power transformers. Low-voltage side switching equipment are LT switchgear of the transformers. And engineers locate it in a building that is with medium-voltage circuit breakers and for distribution circuits with work along with protection equipment, metering and control. Switchgear and transformer line-up may be combined in one housing for industrial applications which is called a unitized substation (USS).
Now you may understand what is a Switchgear. Learn other more engineering topics.