STUDY INFLUENCE OF AIR GAP NUMBERS TO INDUCTANCE VALUES OF SHUNT REACTORS

Abstract

The shunt reactor is a device that plays an extremely important role in the transmission system. It is used to absorb the reactive power generated by the capacitive power on the transmission line when no-load or under-load operation. In addition, the shunt reactor is also to avoid the over-voltage at the end of the lines, maintenance of stabilize voltage at the specified level. One of the important parameters when calculating and designing the shunt reactors is the reactive power, where the inductance is a parameter directly related to the capacity of the device. In order to reduce the flux and avoid saturation of the magnetic circuit, it is necessary to increase the reluctance of the magnetic circuit by adding air gaps in the core. However, this makes an increase of the fringing flux around the air gap, leading to the increase of the inductance value. In order to overcome this challenge,  the new idea of this research is to split a big air gap into  sub- air gaps with  smaller dimensions evenly distributed in the core, instead of using a large air gap like previous studies. Based on the obtained results, the paper will give the appropriate number of air gaps when calculating and designing the shunt reactors.