Variable load overshoot control method for supercritical or ultra-supercritical generator sets

Abstract

The invention relates to a supercritical or ultra-supercritical generating set variable-load overshoot control method. According to the method, water supply overshooting and coal quantity overshooting are conducted separately, and various overshoots are intelligently generated according to a state of the generating set before the load is varied. The control method particularly comprises the following steps that 1, comparison is conducted between a load command and a real load deviation, whether the deviation is larger than a first constant value is judged, if yes, water supply overshooting is triggered, and the overshoot adopts hierarchical control; 2, comparison is conducted between a real intermediate point enthalpy value and a preset value of the enthalpy value, whether the deviation is larger than a second constant value is judged, if yes, the coal quantity overshooting is triggered, and the overshoot adopts the hierarchical control. Compared with the prior art, by means of the supercritical or ultra-supercritical generating set variable-load overshoot control method, the various overshoots are intelligently generated according to the state of the generating set before the load is varied, and load control and steam temperature control of a turbine high-pressure control valve in sliding pressure operation are well achieved.

Description

technical field [0001] The invention relates to the field of automatic control of supercritical or ultra-supercritical generating sets, in particular to a variable load overshoot control method for supercritical or ultra-supercritical generating sets. Background technique [0002] The number of supercritical or ultra-supercritical thermal power generation units is increasing day by day, gradually becoming the main unit of the domestic power grid. Most of the coordinated control methods of units are based on CBF (boiler tracking) or CTF (turbine tracking). In CBF mode, the boiler controls the steam pressure and the turbine controls the load; while in the CTF mode, the boiler controls the load and the turbine controls the steam pressure. . As power grid dispatching has higher and higher requirements for thermal power unit AGC control, the unit mainly adopts CBF-based control mode to speed up load response and improve load control accuracy. However, this method requires the t...

AI Technical Summary

Problems solved by technology

The conventional overshooting method is to increase or decrease the corresponding coal and water volume synchronously with the change of the load command. In the case that the turbine control valve does not participate in the adjustment, the load response capability of the unit cannot be effectively improved.

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