Subsynchronous oscillation monitoring control system

Abstract

The invention provides a subsynchronous oscillation monitoring control system. The system is composed of a monitoring control device, a synchronous phasor measurement unit (PMU) and a monitoring analysis master station. The monitoring control device quickly and accurately identifies the subsynchronous oscillation working condition through the power track tracking identification technology. Meanwhile, the sub-synchronous oscillation of the power grid is quickly balanced before torsional vibration protection action of the thermal power generating unit via a control strategy of sub-wheel classification through combining with the modal frequency characteristics of the thermal power generating unit.

Description

technical field [0001] The invention designs a subsynchronous oscillation monitoring and control system, and specifically relates to the monitoring field of subsynchronous oscillation. Through the subsynchronous oscillation identification technology of power trajectory tracking, combined with the modal frequency characteristics of thermal power units, the subsynchronous oscillation of the regional power grid can be effectively quelled by adopting the control strategy of wheel classification. Background technique [0002] Subsynchronous oscillation belongs to the oscillation instability of the system. It is caused by a special electromechanical coupling in the power system. The biggest harm is that the severe electromechanical coupling may directly lead to serious damage to the rotor shafting of large turbogenerators. damage, causing major accidents and endangering the safe operation of the power system. In recent years, the promotion of large-scale new energy power grid con...

AI Technical Summary

Problems solved by technology

[0002] Subsynchronous oscillation belongs to the oscillation instability of the system. It is caused by a special electromechanical coupling in the power system. The biggest harm is that the severe electromechanical coupling may directly lead to serious damage to the rotor shafting of large turbogenerators. damage, causing major accidents, and endangering the safe operation of the power system

In recent years, the promotion of large-scale new energy power grid connection and DC transmission projects of the State Grid has led to the application of a large number of power electronic equipment, which may introduce interharmonics into the power grid, further causing subsynchronous oscillations, and seriously endangering the safety of the power system.

In particular, the structure and grid connection method of the wind power generation system are fundamentally different from those of traditional thermal power generation units, and the wind farm group is composed of various types of wind turbines, which leads to the subsynchronous oscillation problem of large-scale wind power bases. become very complicated

[0003] At present, domestic monitoring and control methods for subsynchronous oscillation in large-scale new energy areas are not high, which are mainly reflected in: 1) Electrical currents, voltages, etc. The quantity is phasor data, and the frequency of sending data is low (usually less than 50Hz), which does not meet the data requirements of subsynchronous oscillation analysis

2) There is still a lack of in-depth research on the identification of subsynchronous oscillations based on embedded devices

There have been articles written that did not study the calculation method and effect of the coexistence of subsynchronous components and supersynchronous components of interharmonic currents

3) There is a lack of control strategies to quell the subsynchronous oscillation of the power grid, and only thermal power units have a line of defense for torsional vibration protection

The existing WAMS cannot provide these data, nor can it be analyzed and displayed, and it is impossible to intuitively assess the scope of influence of subsynchronous oscillations

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