The invention discloses a
new energy station broadband oscillation online early warning method based on a virtual split ratio, and belongs to the technical field of power
system stability analysis and control. The method comprises the following steps: injecting a
harmonic wave small disturbance
signal into a current or
voltage sampling value of a
new energy converter, synchronously recording a
static var generator (SVG)
branch current waveform and extracting a disturbance component, and calculating a virtual shunt ratio; obtaining wide
frequency band data through frequency sweeping, and obtaining
a domain expression of a virtual split ratio through
vector fitting; and solving the zero point of the expression to obtain a
station characteristic root, and carrying out oscillation risk judgment and early warning according to the position of the
station characteristic root on the complex plane. According to the method,
control parameters and line parameters of the
new energy converter in the station do not need to be obtained, a high-power disturbance source is not needed, the problems that an existing method is high in parameter dependence degree, modeling is difficult, and the calculated amount is large are solved, and rapid online early warning of the
broadband oscillation risk in the full
black box state of the new energy station is achieved.