Analysis of Stability Degree for Combustion of Waste-to-Energy Plants with Fuzzy Relational Map of Sensors — Improvement of Map Construction Method

Abstract

In Waste-to-Energy plants, combustion is dependent on many complex factors and a sign of unstable states appears in other locations. We have proposed a fuzzy relational maps of many sensors (FuRMS) for expressing relationships between many sensors as relations between fuzzy sets of sensor values. We use data sets of the same combustion state for constructing a fuzzy relational map. We calculate strengths of relationships between fuzzy sets of sensors based on the distribution of sensor values, considering relationships between sensors as fuzzy rules. The calculation results for all combinations of sensors are called a fuzzy relational map. For evaluating unknown data with the maps, we calculate the weighted sum of degrees of consistency with the relational map. The many sensor pairs with weak relationships get greater weights in an evaluation value. In this paper we propose a method to exclude such data, assumed to be a uniform distribution, from the data set for constructing maps. It makes the evaluation values greater with strong relationships. We construct fuzzy relational maps using data of a certain plant with two methods, one this method and the other the previous method, and compare evaluation values for unknown data.