Online detection of deviation in performance of multichannel dynamical processes

In this paper a computational method for detection of deviation in performance of multiple parallel working channels in a dynamical process is proposed and discussed. The method consists of the following computation steps: one-dimensional multi-agent clustering of the outputs of the channels; similarity analysis of all pairs of channels; calculating the weighted global distance for each channel; static and dynamic ranking of the deviation of all channels. The proposed method is intended to work in online mode by continuously processing Data Blocks with fixed length and the respective results are the form of the ranking positions of the channels. The process with Rank 1 is the most deviated process channel. An experimental example is given in the paper for detection and analysis of the deviation in performance of six batteries used for driving a small electric vehicle. Other possible applications for online monitoring and performance evaluation of dynamical processes are also discussed in the paper.

I. Introduction and Problem Statement

There are many types of dynamical processes in the industry, such as chemical, metallurgical and machinery plants, where the equipment operates in a parallel way - as several parallel production lines. Then each line can be viewed as one “channel” or “sub-process” of the whole industrial process. Normally all the channels receive the same input load (such as material flow, energy) and work under the same regime parameters (such as temperature, pressure, rotation speed etc.). The main reason for designing such multichannel production structure is the need to increase the production output of the whole plant or to increase the output power. This is the case of the power generation plants or the case of electric battery, consisting of large number of parallel and serially connected battery cells. Another important reason to design a multichannel structure of the dynamical process is to increase the reliability of the whole production process. Then, if the performance of a certain production line (channel, battery cell) deteriorates significantly from that one of the other parallel lines, it can be safely isolated (shut-down) from the whole production process for maintenance, without shutting-down the whole plant.