With the development of society

the electricity consumption structure and scale for industry and agriculture in our country has significant changes.Power users need to consume a lot of reactive power and

at the same time

request more and more strict demands in the quality of power supply.To obtain bulk of reactive load directly from the power transmission grid not only causes significant increasement of loss and over low power factor of distribution grid

but also a serious effect on the quality of voltage

it is necessary to conduct reactive power compensation in low and medium voltage distribution grid.This paper mainly studies the principle of reactive power compensation

the application of the reactive power compensation equipment in low and medium voltage distribution grid

and some cautions in the reactive power compensation.