The invention discloses an aircraft
flight process soft measurement
algorithm based on an improved flow model. According to the method, a conditional cycle real value non-volume preserving model (CP-RNVP) and a conditional streaming
soft sensor (CFSS) framework are provided for solving the problems that the data distribution difference is obvious and samples are unbalanced under the multi-working-condition operation condition of an aero-engine. The CP-RNVP model comprises three key components: (1) an adaptive
mask mechanism based on feature correlation, wherein the range and
granularity of
feature selection are dynamically adjusted according to feature importance and correlation; (2) the multi-period affine
coupling layer is used for modeling a complex period mode in data by introducing learnable multi-frequency parameters; and (3) a non-explicit condition injection method is adopted, condition information features are extracted through the sub-network and are adopted as modulation items in affine
coupling transformation, and joint learning of multi-working-condition distribution is realized. Based on a CFSS soft measurement framework developed by a CP-RNVP model, multi-level training
verification of soft measurement is realized by utilizing reversibility of a flow model, a soft measurement head is designed in the process of
data mapping and inverse transformation, and multi-level soft measurement prediction and
verification are carried out. Experiments show that the method has a remarkable effect on solving the multi-working-condition imbalance problem, compared with an existing method, the soft
measurement precision is remarkably improved, and meanwhile the data generation quality and the distribution fitting capacity are better. The method is suitable for the fields of aero-engine state monitoring, health management and the like.