2-1 Which devices belong to the primary device? Which devices are secondary devices? What is their function?
A: Generators, transformers and circuit breakers, etc., are commonly referred to as primary equipment for the production, conversion, distribution and use of electrical energy. And devices which are necessary for system running under the state of measurement, monitoring and protection equipment called secondary equipment. Such as instrument transformers, measuring meters, relay and automatic devices. Its main function is to start and stop units, adjust the load and, switching equipment and lines to monitor the operation of major equipment status.
Brief Introduction to the Characteristics of 300MW Generating Unit Electrical Wiring and Main Equipment Functions.
A: 1) generator and transformer connection using the generator - transformer unit wiring;
2) In the main transformer low-voltage side of a high-voltage transformer, supply power plant;
3) At the generator outlet side, there are three sets of voltage transformers and a group of surge arresters connected by high voltage fuses;
4) On the generator output side and the neutral point side, each group is equipped with 4 current transformers;
5) Neutral point earthing transformer is connected to generator neutral point;
6) high-voltage transformer factory with high-voltage side, each with four current transformers.
Voltage transformer: they are high voltage into low voltage transformers, used for a variety of equipment and instrumentation, high-voltage fuses used for short-circuit protection; current transformers are Neutral grounded transformer used to limit the capacitive current.
2-4 factors affecting the development of transmission voltage rating What are the factors?
A: 1) long-distance transmission of energy;
2) high-capacity transmission of energy;
3) to save capital investment and operating costs;
4) Power system interconnection.
Main Wiring Form and Characteristics of AC 500 kV Substation.
A: At present, the main wiring of the 500kV substation in our country generally adopts double bus four-section with special bypass bus and 3/2-off
Two ways of wiring. One of the 3/2 circuit breaker wiring has the following characteristics: any bus overhaul or failure there will be no power failure; any circuit breaker maintenance does not cause power outages; even in the two groups of bus failure (or a group of bus overhaul another group of bus Failure) of the extreme conditions, the power can continue to transport. When any circuit breaker in a string withdraws or overhauls. This kind of wiring operation is convenient, the operation is simple, the isolating switch is used as the isolation live equipment only when being overhauled.
