Abstract:Regarding the problem that the effective chlorine concentration during disinfection requires offline sampling analysis and has poor real-time performance, a study was conducted on the soft measurement method of effective chlorine concentration based on multi-sensor information. Taking pH value and oxidation-reduction potential (ORP) as input variables and the measured effective chlorine concentration by DPD spectrophotometry as the output, a nonlinear mapping model of effective chlorine concentration was constructed. The improved grey wolf optimization algorithm was used to globally optimize the penalty factor and kernel width parameters of the kernel extreme learning machine, and Tent chaotic mapping, Levy flight mechanism and golden sine strategy were introduced to improve the population diversity, global search ability and local exploration ability. Experimental results show that the MAE, RMSE and R2 of the IGWO-KELM model on the test set are 0.6497, 0.8634 and 0.9654 respectively, and the prediction accuracy and generalization performance are superior to those of the KELM and GWO-KELM models. The proposed method achieves accurate estimation of the effective chlorine concentration and can provide technical support for concentration monitoring during the disinfection process and subsequent intelligent regulation.