Method and device for approximation of pure lag

Abstract

The invention discloses a method and device for the approximation of pure lag, and the method comprises the steps: performing six consecutive first-order inertial inverse operations of an input signalby a preset first-order inertial inverse operation formula; solving the sum of a first output signal, a second output signal, a third output signal, a fourth output signal, a fifth output signal anda sixth output signal; performing a fifth-order inertial operation of a seventh output signal by a preset fifth-order inertial operation formula; taking an output signal of the subtraction operation as a ninth output signal, and performing four consecutive first-order inertial operations of the ninth output signal through a preset first-order inertial operation formula; solving the sum of a tenthoutput signal, an eleventh output signal, a twelfth output signal and a thirteenth output signal; multiplying the output signal of the subtraction operation by a preset second constant of 0.8333 to obtain an approximately pure lag output signal. The method solves a technical problem that a mode of approximating the pure lag through the only the first-order inertial link is larger in pure lag approximation error.

Description

technical field [0001] The invention relates to the technical field of automatic control, in particular to a method and device for approximate pure hysteresis. Background technique [0002] In model-dependent control methods, such as PID plus Smith predictor control methods, it is necessary to identify accurate models of the plant including accurate pure-lag models. The main feature of the pure hysteresis model is that there is no output during the pure hysteresis period. An obvious negative effect of the pure hysteresis model is the jumping problem of the controller output. In some process control systems that have high requirements on the output control amount, it is a problem that needs to be dealt with. The problem. [0003] At present, one of the ways to solve the jump problem is to use only the first-order inertial link to approximate the pure lag, but there is a technical problem that the pure lag approximation error is large. Contents of the invention [0004] Th...

AI Technical Summary

Problems solved by technology

[0004] The invention provides a method and device for approximating pure hysteresis, which solves the technical problem that the pure hysteresis approximation error is relatively large by only using the first-order inertial link to approximate pure hysteresis

Images