A method and system for suppressing subsynchronous oscillation control based on SVG

Abstract

The invention relates to a reactive compensation device and discloses a sub-synchronous oscillation suppression control method based on SVG in the field of stabilization and control of an electric power system. The sub-synchronous oscillation suppression control method is characterized by comprising the following steps: by utilizing a voltage synchronous signal obtained by performing PLL (Phase Locking Loop) phase locking on voltage of an SVG grid connection point bus, performing abc / dq coordinate conversion on a sub-synchronous oscillation current signal, which is acquired from an SVG compensation bus or a PCC (Programmable Computer Controller) point in a system of the SVG, filtering, then extracting a current signal containing sub-synchronous oscillation information, and performing phase correction and amplitude compensation to obtain a sub-synchronous oscillation suppression current instruction signal; generating current and power for suppressing sub-synchronous oscillation by using a power signal generation device. With SVG-based additional damping control, the engineering implementation cost is low and the aim of sub-synchronous oscillation suppression can be realized by only performing system upgrading of an SVG controller, without the need of adjusting parameters including frequency and the like; wide-range suppression of each sub-synchronous oscillation frequency and complementation frequency of the sub-synchronous oscillation frequency can be realized.

Description

technical field [0001] The invention relates to a control method for suppressing subsynchronous oscillation, in particular to a method and system for suppressing subsynchronous oscillation based on SVG. Background technique [0002] In recent years, my country's new energy grid-connected installed capacity has achieved rapid growth. Centralized grid-connected, long-distance transmission of wind power, photovoltaics and other new energy sources, after large-scale access to high-voltage direct current HVDC transmission systems, due to wind power, photovoltaics and other power generation The rapid and independent active control characteristics of photovoltaics and wind turbines in the power station are likely to cause subsynchronous oscillations in the power transmission and grid-connected systems, making it difficult for this type of new energy to be connected to the grid, and it is more likely to damage the generator set and even seriously threaten the safe operation of the gri...

AI Technical Summary

Problems solved by technology

[0004] At present, photovoltaic and wind power and other new energy grid-connected power stations are equipped with reactive power compensation equipment with a certain capacity, but most SVC or SVG do not have the subsynchronous oscillation suppression function or the suppression function is very limited, and the response speed of SVC compensation equipment is slow and the voltage characteristics are poor. , and the control system based on SVG to suppress subsynchronous oscillation is generally applied based on the speed feedback signal. On the one hand, this structure often cannot obtain the speed signal in new energy grid-connected systems such as wind farms or photovoltaic power plants, or the oscillation suppression of the additional damping Only for electrical and mechanical specific sub-synchronous frequencies, it cannot be dynamically tracked and adjusted, and the suppression effect is very limited; on the other hand, even if non-speed electrical signals are used as input, the system engineering implementation is often complicated, and it is impossible to control the sub-synchronous and its complementary frequency signals Achieve comprehensive suppression over a wide frequency range

Images