What is the difference between current limiting reactor and series reactor?

Varieties and characteristics of current limiting reactor

1 concrete column reactor

Reactors with voltage of 20kV and below and current of 150-3000a are usually arranged in hollow concrete. After winding the coil, the concrete is poured into a stable group. This kind of layout is simple in manufacture, low in cost, reliable in operation and convenient in protection. It belongs to indoor assembly and is generally single-phase. When three phases are formed, there are three types of arrangement, that is, three single phases are stacked vertically from bottom to top; two phases are stacked, one phase is parallel; three phases are parallel in degree. In order to reduce the tensile force received by the supporting insulator of interphase insulation, the winding direction of the central phase reactor should be opposite to that of the high-low two-phase winding when the three-phase stack is arranged; in the environment of two-phase stack and one phase parallel, the winding direction of the two-phase reactor should be opposite. For reactors above 400A, the coils are wound in parallel with more than two cables. In order to make the current distribution of parallel wound cables average, the transposition shall be stopped when the parallel cables are wound.

2 split reactor

The concrete reactor with central tap is called split reactor. When the split reactor is used, the central terminal is connected to the power supply, and the first and last terminals are connected to the load. In general, the purpose of splitting the arm (i.e. two branches) of the reactor is the opposite, and the winding direction of the two arms is the same, so the flux of the two arms is weakened each other, so that the useful reactance value of the two arms of the reactor is very small. In addition, the current of one arm is still very small compared with that of the short-circuit arm, and the influence of mutual inductance magnetic flux on the short-circuit arm can be ignored, so the useful reactance of the short-circuit arm is very large, which plays an obvious role in current closure.

3 oil immersed current limiting reactor

The oil immersed reactor is mostly used for outdoor 35kV voltage grade, because the reactor is located in the iron oil tank, the leakage flux will form consumption and fever on the tank wall. In order to reduce the consumption and fever on the tank wall, the tank wall is equipped with magnetic shunt or magnetic barrier.

Series reactor is a kind of electrical equipment with certain reactance value, which is made of metal wire. It is connected to the electrical circuit in series and is mainly used to limit the short-circuit current. In the innovation of duhuidian analysis, the short-circuit capacity is limited by operating the series reactor, so that some relays with insufficient breaking capacity can be used continuously. It is generally used in the power system of 35kV and below.

According to the different layout, the series reactors are dry air core reactor, dry dead core reactor and oil immersed dead core reactor.

Dry type air core reactor is oil-free, with small music, good magnetization characteristics, high machine strength and quiet operation. However, the dry-type air core reactor relies on the atmosphere to conduct magnetic field, so the installation space of the dry-type air core reactor is large.

Compared with the dry air core reactor of the same capacity, the oil immersed dead core reactor has the advantages of small consumption, simple installation and less land occupation.

Compared with the oil immersed reactor of the same capacity, the dry-type dead center reactor is smaller, oil-free, easy to install and protect, but the noise is slightly higher. In recent years, with the continuous progress of reactor manufacturing technology, the quality of dry-type dead core reactor has made great progress. Dry type dead core reactors are used more and more widely. Dry type dead core reactor is more suitable for installation in cabinet and indoor use.