Switchgear refers to a complete set of power distribution devices assembled from primary equipment and secondary equipment according to a certain plan.
It is mainly used to control and protect circuits and equipment.
Switchgear can be divided into high voltage switchgear (fixed type and handcart type) and low voltage switchgear (fixed type and drawer type) according to the voltage level.
The structure of high-voltage switchgear
It is mainly divided into busbar room, circuit breaker room, secondary control room (instrument room), and feeder room.
Generally, there is steel plate isolation between each room.
Switchgear internal components
Bus (busbar), circuit breaker, conventional relay, integrated relay protection device, measuring instrument, isolating knife, indicator light, grounding knife, etc.
Application Classification of Switchgear
1. Incoming Cabinet:
also called the receiving cabinet, it is the equipment used to receive electric energy from the power grid (from the incoming line to the busbar).
Generally, it is equipped with circuit breakers, CTs, PTs, isolating blades and other components.
2. Outgoing cabinet:
also called feeder cabinet or power distribution cabinet.
It is the equipment used to distribute electric energy (from bus to each outlet).
It is generally equipped with circuit breakers, CTs, PTs, isolating blades and other components.
3.Busbar connection cabinet:
also called busbar breaker cabinet, which is used to connect two busbars (from busbar to busbar).
Busbar connection is often used in single busbar segmentation and double busbar systems to satisfy users in choosing different operating modes The requirements or guarantees of selective load removal in case of failure.
also called voltage transformer cabinet.
it is generally installed directly on the bus bar to detect the bus voltage and realize the protection function.
Mainly install voltage transformer PT, isolating knife, fuse and arrester etc. inside.
It is used to isolate the busbars at both ends or to isolate the power receiving equipment from the power supply equipment.
It can provide operators with a visible end point to facilitate maintenance and repair operations.
Since the isolation cabinet does not have the ability to break and connect the load current, the handcart of the isolation cabinet cannot be pushed or pulled when the circuit breaker that cooperates with it is closed.
In general applications, it is necessary to set the interlock between the auxiliary contact of the circuit breaker and the isolated handcart to prevent misoperation by the operator.
It is mainly used for measuring electric energy (kWh), and it is divided into high voltage and low voltage.
Generally, it is installed with isolating switch, fuse, CT, PT, active watt-hour meter (traditional meter or digital meter), Power meter, relay, and some other auxiliary secondary equipment (such as load monitor, etc.).
Static Var Generator, English description: Static Var Generator, referred to as SVG.
Also known as high-voltage dynamic reactive power compensation generator, or static synchronous compensator.
It refers to a device that performs dynamic reactive power compensation by a self-commutated power semiconductor bridge converter.
SVG is currently the best solution in the field of reactive power control.
Compared with traditional tuning cameras, capacitor reactors, and traditional SVC with thyristor controlled reactor TCR as the main representative, SVG has unparalleled advantages.
8.Gas-filled switch cabinet:
also called enclosed combined electrical cabinet.
it is a closed combination of circuit breakers, disconnectors, grounding switches, CT, PT, arresters, busbars, etc.
in a metal shell, and then with good insulation performance and arc extinguishing performance Gas (usually sulfur hexafluoride SF6) is used as an insulation measure between phases and the ground.
It is suitable for high-voltage and high-capacity power grids for distribution and control.
Switchgear manufacturing equipment:
Manual busbar machine