Analysis of the broadband oscillation mechanism of wind, solar, and fire bundling

The large-scale development of new energy bases and the continuous development of high-voltage transmission systems have accelerated the change of China’s energy system, making the “double-high” characteristics of the power system more significant. The broadband oscillation problem in the wind-fire bundled high-voltage direct current (LCC-HVDC) transmission systems is investigated. A small-signal model and an impedance model of the dynamic characteristics of doubly-fed wind farms, thermal power plants, photovoltaic power plants, and DC transmission systems are established by graphical modeling, and the oscillation modes of these systems are obtained by using the eigenvalue analysis method, and the causes of the interaction effects are analyzed in the frequency domain. The time-domain simulation of the part that generates interaction effects was verified by PSCAD/EMTDC. The results show that the generation of broadband oscillation at 223.61 Hz is triggered by the system’s negative damping characteristics of the system, and the amplitude of the system oscillation at a specific frequency can be effectively changed by changing the parameters of the components to improve the stability of the system, which provides a reference for the suppression of broadband oscillation of the large-scale new energy grid-connected.