The invention provides a gas extraction evaluation unit multi-parameter collaborative automatic metering method and
system. The method comprises the steps that
gas concentration, multi-path
mixed gas flow velocity, pipeline pressure and multi-component gas data are collected, a
radial basis function network is input, gas density-
viscosity correction parameters and cross interference correction parameters are output, and a flow velocity compensation coefficient is calculated; calculating a first-order difference norm and fluctuation entropy of a
gas concentration sequence in a rolling time window, and judging a
signal state according to a joint criterion: correcting the concentration by using a correction parameter when the
signal is stable, decomposing and reducing
noise by using a
wavelet packet when the
signal fluctuates, and uniformly outputting and correcting the
gas concentration; constructing a flow velocity-pressure
covariance matrix, calculating a characteristic value time change rate, generating a
confidence factor in combination with a fluctuation entropy, carrying out weighted fusion on each path of flow velocity to obtain a reference
mixed flow velocity, and carrying out correction by using a compensation coefficient to obtain a compensated
mixed flow velocity; and aligning the time sequences of the corrected gas concentration and the compensated
mixed flow velocity, and calculating the gas extraction pure quantity based on the two time sequences.