Modelling and control of MIMO gasifier system during coal quality variations

摘要

Coal gasifier converts coal into synthesis gas (syngas). The quality of syngas is highly influenced by variation in coal quality (calorific value of syngas) thereby affecting power generation capabilities of integrated gasification combined cycle (IGCC) plants. The mathematical model for a coal gasifier is found to be complex because of its nonlinearity and multivariable in nature. The higher order state space time domain model of coal gasifier given in ALSTOM benchmark challenge II has been taken as a reference plant in this work. This higher order model has been transformed into second order S-domain models. P1D controller with filter approach has been applied to these lower order models to study the gasifier dynamics during the coal quality variations in either direction with respect to the design value. The obtained results are quite promising.