A Subsynchronous Oscillation Monitoring and Analysis Method Based on Electrical Signals of Converter Station

Abstract

The invention provides a convertor station electrical signals-based subsynchronous oscillation monitoring analysis method. The method includes the following steps that: step 1, acquiring and selecting appropriate converter station electrical signals x (k); and step 2, adopting a windowed interpolation FFT algorithm and an ESPRIT algorithm to identify the subsynchronous oscillation information of the electrical signals x (k). Compared with the prior art, and according to the convertor station electrical signals-based subsynchronous oscillation monitoring analysis method provided by the invention, the windowed interpolation FFT algorithm and the ESPRIT algorithm are applied to electrical signal analysis, and therefore, analysis precision can be improved; and monitoring and prevention of subsynchronous oscillation can be performed based on the method, so that the security and economical efficiency of the operation of a power grid and a unit can be improved.

Description

technical field [0001] The invention relates to a subsynchronous oscillation monitoring method, in particular to a subsynchronous oscillation monitoring and analysis method based on electrical signals of a converter station. Background technique [0002] At present, the capacity of the turbogenerator set is large, and the low-order torsional vibration frequency range of the shafting is generally between 10Hz and 40Hz. The actual power system is in a dynamic equilibrium state, and system disturbances may cause different amplitudes of the shafting of the unit subsynchronous torsional oscillations. Due to bearing friction, wind resistance and other reasons, the shafting mechanical system of the unit shaft system presents positive damping characteristics. If there is no series compensation, HVDC and other devices in the sending system of the unit, the sub-synchronous frequency complementary to the shafting sub-synchronous torsional vibration frequency generally oscillates in the...

AI Technical Summary

Problems solved by technology

[0008] The problem with the above countermeasures is that the grid side cannot grasp the shaft torsional vibration status of each unit during dispatching operation, cannot predict the occurrence of subsynchronous oscillation, and cannot take active measures to prevent the occurrence of subsynchronous oscillation

However, the speed signal of multiple units has a high sampling rate and a large amount of data, and it is difficult to transmit it to the converter station in real time through communication means. Therefore, it is necessary to study the use of electrical signals for subsynchronous oscillation monitoring and analysis of multiple units.

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