Guangdong power grid is a receivingend power grid at the end of eight AC main lines and eight DC main lines

in which the power load exceeds 80 GW. The problem of voltage stability is thus outstanding and the insufficient dynamic reactive power support for power grid is an issue demanding prompt solution for the voltage stability. As an important reactive power supply

generators have abundant reactive power reserves to be used

while there’s no need to increase investment. To make bigger use of the generator reactive power resource and bring into play the role of negative reactive current compensation in improving the reactive power output of the unit

the paper adopts negative reactive current compensation of security and potential risk for the stable operation of unit

focusing on the reactive current compensation to the influence of reactive power allocation between the units

the influence on unit damping adjustment

and the effects on power system stabilizer (PSS) and automatic voltage control (AVC). By referring to the actual situation in Guangdong power grid

it is concluded that unit and grid stability risks are controllable if the negative reactive current compensation varies from 0 to -10%. It is a meaningful reference for the optimization and setting of the generator reactive current compensation coefficient.