For all operations related to power systems – the main constituents of power generation, transmission, and distribution systems – substations are required for completing the required actions. Substations are groups of electrical equipment through which customers get supply of electrical power from generating stations. The electrical quantity in substations can be altered by varying the voltage and frequency levels to provide quality power to consumers. Substations are classified into various types depending upon their applications, namely indoor substation, outdoor substation, generation substation, converter substation, distribution substation, switching substation, transmission substation, pole-mounted substation, and collector substation. A substation is a combination of various electrical equipment, with the most important ones being transformers, conductors, insulators, isolators, circuit breakers, relays, lightning arresters, bus bars, and capacitor banks.
Transformers are electrical machines used for transforming power from one circuit to another without changing the frequency. These transformers are used to step up or down the voltage levels of a system for transmission and generation purposes. There are multiple varieties of transformers based on their design, purpose, utilization, and installation. You can get the best kinds of toroidal, medical isolation, three-phase, EI, audio line matching, SMPS, UI, and power transformers in India at Miracle Electronics, one of the most reputed names in the country for such electronic equipment.
Conductors are materials that are made of metals that comply with electrical property conductance, and allow the flow of electric charge by permitting free movement of electrons to flow through them. This helps in power transmission or electric energy transfer from generating station to consumer point, where power is consumed by the loads. The most commonly used conductors used in power systems are those made of aluminum.
Insulators, unlike conductors, do not allow free movement of electrons or electric charge through them. This is why insulators resist electricity with their high resistance, and are used for insulation while erecting electric poles with conductors to avoid short circuits. The various types of insulators include suspension, stray, pin, strain, and shackle insulators.
Isolators are manually operated mechanical switches that isolate the faulty sections or those sections of conductors or circuits that need to be repaired, in order to avoid occurrence of harsher faults. The various types of isolators used in different applications include single-break, double-break, line, and bus isolators.
Due to short circuits or any other faults, the faulty sections are disconnected automatically by circuit breakers to protect the substation and its components from over currents or over load. After the fault is rectified, the original circuit is then rebuilt. Different types of circuit breakers are designed based on different criteria and usage, with the most commonly used ones being oil, air, vacuum, and SF6 circuit breakers.
Relays are used for disconnecting circuits manually or automatically. They consist of excited or energized coils connected in such a way that the contacts of relay when closed activate the relay to break or make the circuit connection. There are multiple types of relays like voltage, auxiliary, over current, directional, reclosing, and microcontroller relays.
In cases of light surges, a high voltage passes through all the electrical components of a substation, causing them damage. To avoid this issue, lightning arresters are placed to pass the lightening surges to the earth.
Bus bars are current carrying conductors that have multiple numbers of incoming and outgoing line connections. These are classified into single bus, double bus, and ring bus bars.
Capacitor banks are sets of identical capacitors connected in series or parallel within an enclosure, used for power factor correction and protection of substations. These banks are sources of reactive power, and can reduce the phase difference between voltage and current. They are the best equipment for maintaining power factor and correcting power lag problems.