Control method for preventing oscillation during power regulation of thermal power unit

Abstract

The invention relates to a control method for preventing oscillation during power regulation of a thermal power unit. The control method comprises the following steps of: adding a self-adaptation parameter control link having great influence on the power of the thermal power unit in a power control circuit of the thermal power unit, thus achieving regulation quality of not influencing power when main operation parameters of the thermal power unit greatly change; adding a filter link and enhancing the damping of a closed-loop regulation circuit of the thermal power unit to avoid a resonance zone between the closed-loop regulation circuit and a power grid, thus enabling the control on the power of the thermal power unit to be more stable; performing linear correction on DEH (Digital Electro-Hydraulic Control System) control on a steam turbine governing valve to improve the linearization level of the steam turbine governing valve, thus promoting the power adjustment on the thermal power unit to be more stable; and sending alarms and outputting signals for releasing the closed-loop control of the thermal power unit if the power of the thermal power unit oscillates during the closed-loop control, thus rapidly eliminating the oscillation after the oscillation occurs. The control method provided by the invention can greatly reduce the low frequency oscillation of a power system, which is caused by the power oscillation of the thermal power unit. The control method provided by the invention has the obvious advantages of safety and stability.

Description

technical field [0001] The invention belongs to the field of thermal automatic control of thermal power plants, and aims at the risk of power control oscillation commonly found in current thermal power units. Through the application of this control method, the low-frequency oscillation of the power system caused by the power control oscillation of thermal power units can be greatly reduced, and the power system can be improved. The safe and stable operation level of the unit and the power grid. Background technique [0002] In recent years, the power low-frequency oscillation of domestic thermal power units has occurred from time to time, which has brought a great threat to the stable operation of the power grid. The stable operation of the unit is directly related to the safe and stable operation level of the power grid. The power oscillation of the unit will cause the oscillation of the power grid, which seriously threatens the safe and stable operation of the power grid. ...

AI Technical Summary

Problems solved by technology

[0003] The excitation system may weaken the damping torque of the unit, and even cause the damping torque to be negative. Therefore, the negative damping mechanism is widely used in low-frequency oscillation analysis and research on suppression methods. With the input of a power system stabilizer (PSS) on the excitation side, It has a very good suppression effect on the oscillation caused by the low damping of the power grid, but the power low-frequency oscillation caused by the complex control object and control system of the generator set is still happening continuously

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