Electrical main wiring forms and advantages and disadvantages of introduction

The form of electrical main wiring has a busbar wiring, busbarless main wiring.

(A) with busbar wiring?

1, single bus wiring

All power lines and lead wires are connected to the same set of buses. Single bus wiring is suitable for a small substation with fewer circuits, generally for three loads, two power feeds into a single bus for two loads.

Advantages: simple wiring, less equipment, easy to operate, cheap, as long as the power distribution device to leave a margin, the bus can be extended to both ends, can be expanded.

Disadvantages: reliability, poor flexibility. Bus failure, bus and bus disconnect switch maintenance, all circuits need to be shut down, resulting in a long-term power outage of the whole plant or station; any circuit breaker maintenance, the circuit where it will be shut down.

2, segmented single-bus connection

Two power supply a use a backup, segmented circuit breaker connected to run. When the two power supplies are working at the same time for each other as a backup, the sectional circuit breaker is disconnected from the operation.

Advantages: the two bus segments can be split operation, can also be run in parallel; important users can be connected to different bus segments of the double circuit, to ensure uninterrupted power supply; any bus or disconnect switch overhaul, only stop the segment, the rest of the segment can continue to supply power, reducing the scope of power outages.

Disadvantages: segmented single bus increases the segmented part of the investment and footprint; a section of the bus failure or maintenance, there is still a blackout; a circuit breaker maintenance, the circuit blackout; the need for expansion to both ends of the balanced expansion.

3, double bus connection

Each circuit is connected to two buses through circuit breakers and two sets of disconnect switches.

Advantages: the switch is isolated, easy to control.

Disadvantages: only applicable to a large number of primary and secondary loads of large substation.

4, with bypass wiring

Advantages: flexible operation and scheduling, normal operation of the two buses and all the circuit breakers, into a multi-way loop power supply;? Convenient operation during maintenance, when a group of bus stops branching, the circuit does not need to switch, any one circuit breaker maintenance, the circuit is still in accordance with the original wiring Timing, do not need to switch.

Disadvantages: investment costs are larger, occupy more equipment intervals.

(B) the main connection without bus

5, line - transformer unit connection

Advantages: simple wiring, less equipment, good economy.

Disadvantages: only suitable for only one main transformer of small substations.

6, bridge connection

Advantages: can realize the full use of power lines and transformers. Two circuit breakers connected to the lead line, so that the lead line operation is flexible and convenient. When the line is faulty, the fault line circuit breaker disconnected, self-transfer device will be put into the sectional circuit breaker, does not affect the operation of the transformer.

Disadvantage: in the transformer casting and cutting operation needs to be the corresponding line blackout.

7, polygonal wiring

Polygonal wiring is the circuit breaker and disconnecting switch is connected to each other, and each circuit breaker on both sides of the disconnecting switch, by the disconnecting switch between the circuit of an electrical main wiring connection.

Advantages: polygonal equipment, investment, operational flexibility and reliability is better, stop the usual situation for the double connection, any one circuit breaker overhaul does not affect the power supply, due to the lack of bus, in any part of the connection failure, the operation of the grid are less impact.

Disadvantage: the number of the same way is limited, because when the ring has a circuit breaker maintenance to open the ring operation, when the other same way failure will cause two same way blackout, expanding the scope of the fault blackout, and the longer the open ring operation, the greater the shortcomings of this disadvantage is the greater the number of circuit breakers in the ring, the greater the opportunity to open the ring for maintenance.

Baidu Encyclopedia - Electrical Main Wiring