Combustion State Estimation Using a State Space Model

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

There are state quantities in combustion facilities that are difficult to measure directly using conventional instruments.

Innovation Solution

A state space model is used to estimate these difficult-to-measure state quantities by setting them as objective variables and using observed and calculated quantities as explanatory variables, with a processor executing steps to calculate and correct estimates based on measured values.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional measuring instruments are used to measure state quantities in a combustion facility, then the measurement is straightforward and reliable, but many important state quantities cannot be measured directly at all

Engineering Contradiction:
Improvestate quantity measurementVSAvoiddifficulty of measuring state quantities
Core Design Contradiction:
Measurement precisionVSDifficulty of detecting and measuring

Solution Approach 1:

The patent introduces a state space model as an intermediary system that connects measurable quantities (explanatory variables) to unmeasurable state quantities (objective variables). The model acts as a mediator that translates accessible measurements into estimates of inaccessible parameters through mathematical relationships defined by state equations and observation equations.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent replaces physical measuring instruments with a computational estimation system. Instead of using mechanical or physical sensors to directly measure state quantities, the system substitutes a mathematical model-based computational approach that processes measurable data to infer unmeasurable parameters.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Measurement precision

If a state space model is used to estimate state quantities, then difficult-to-measure quantities can be estimated, but the system complexity increases due to the need for state equations and observation equations

Engineering Contradiction:
Improvestate quantity estimationVSAvoidcomplexity of estimation system
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The state space model is designed to be self-correcting through the feedback mechanism inherent in the estimation process. The system automatically adjusts its estimates by comparing predicted values with actual measurements and correcting deviations, eliminating the need for external manual calibration or adjustment of the complex mathematical relationships.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The state space model serves multiple functions simultaneously: it estimates unmeasurable state quantities, predicts future states, processes measurement data, and provides a framework for control decisions. This multi-functionality reduces the need for separate systems for each task, thereby managing overall system complexity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Loss of time

If real-time estimation of state quantities is performed, then combustion control can be performed without time delay, but computational processing time may cause delays

Engineering Contradiction:
Improvetime delay in combustion controlVSAvoidcomputational processing capability
Core Design Contradiction:
Loss of timeVSPower

Solution Approach 1:

The state space model is pre-configured with state equations and observation equations that encode the physical relationships of the combustion system. This preliminary setup allows the estimation algorithm to process measurements efficiently without requiring complex real-time calculations, reducing computational delay while maintaining real-time capability.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP3816515B1Method for estimating state quantity of combustion facility, combustion control method, and combustion control device
Publication Date: 2025.08.20 EBARA ENVIRONMENTAL PLANT
  • EP3816515B1 patent drawingFigure 1
  • EP3816515B1 patent drawingFigure 2
  • EP3816515B1 patent drawingFigure 3

AI summary

Provided is a method for estimating a state quantity that is difficult to measure directly in a combustion facility for combusting a combustible. At least one state quantity that is difficult to measure directly in the combustion facility for combusting the combustible is treated as an objective variable, and at least one observed quantity that can be measured directly at least one observation point established in the combustion facility and/or at least one calculated quantity that can be computed by calculation from the at least one observed quantity is treated as an explanatory variable in a state space model, and the state space model is used to estimate the objective variable.