Precise regulation method for primary frequency modulation of thermal power generating unit with self-adaptive learning characteristics

Abstract

The invention discloses a precise regulation method for primary frequency modulation of a thermal power generating unit with self-adaptive learning characteristics. The method comprises the followingsteps of calculating a primary frequency modulation load instruction; performing pressure compensation on the primary frequency modulation load instruction; and performing power modulation coefficientcorrection on the primary frequency modulation instruction subjected to pressure compensation. The precise regulation method is based on a multi-point function online learning calculation strategy based on periodic batch data processing, solves the problems of nonlinearity and time-varying property of a flow coefficient of a comprehensive valve position instruction of a steam turbine, and ensures accurate action of the comprehensive valve position instruction in any one operation mode and at a variable flow coefficient. The precise regulation method has the advantage that a safe pressure self-adaptive compensation loop is added, so that the safe operation and the proper amount of primary frequency modulation output of the thermal power generating unit under the circumstance that a sliding pressure operation machine unit is under variable working conditions and pressure fluctuation conditions are ensured. By using the precise regulation technology for primary frequency modulation, theprimary frequency modulation precision of the thermal power generating unit can be higher, so that the frequency of a power grid is enabled to be more stable.

Description

technical field [0001] The invention belongs to the technical field of thermal power engineering and automatic control, and in particular relates to a precise adjustment method for primary frequency modulation of a thermal power unit with the feature of self-adaptive learning. Background technique [0002] The primary frequency regulation control of the thermal power unit is to use the energy storage of the unit to realize the rapid adjustment of the unit load through the action of the main steam control valve (see attached figure 1 As shown), it is one of the key control technologies for thermal power units to ensure the safety of the power grid. from figure 1 It can be seen from the figure that the frequency deviation is calculated by the frequency difference-primary frequency modulation load command function to obtain the corresponding primary frequency modulation load command, which generates the main steam valve incremental command through simple proportional operation...

AI Technical Summary

Problems solved by technology

The condition for this expression to hold is that the valve opening μ T It is directly proportional to the cross-sectional area of ​​the valve opening, but the actual opening of the main steam valve is the comprehensive valve position where multiple valves are open, which cannot reach a linear relationship with the overall opening cross-sectional area, and the wear of the valve will also lead to The flow characteristic relationship is not fixed, and there are large nonlinear and time-varying problems, that is, the first problem; in addition, according to the above expression, it can be seen that the steam flow is affected by the pressure in front of the valve, and the pressure change will lead to the change of the steam flow entering the steam turbine So that the output power of the steam turbine changes, that is, the second problem

Images