Non-linear inverse compensation of an SI engine by system identification for robust performance control

Abstract

Treating non-linear systems as equivalent time-invariant systems with associated uncertainty is often excessively conservative and significantly reduces the achievable robust performance. This paper presents a method for reducing the associated uncertainty of non-linear uncertain single-input single-output systems based on Horowitz's method for non-linear quantitative feedback theory. The new method implements a non-linear compensator based on an approximate causal inversion of an identified nominal model. The inverse system compensator reduces the uncertainty associated with the linear time-invariant equivalent system. The method is applied and experimentally validated on the idle speed dynamics of an automotive SI engine system using an electric dynamometer.

Keywords:

• Non-linear
• identification
• inverse systems
• robust performance
• engine control
• QFT

Additional information

Notes on contributors

A. T. Shenton

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