Method and apparatus for controlling an engine capable of operating on more than one type of fuel

Abstract

A control system for an engine capable of operating on more than one type of fuel includes an engine control unit that determines a default fuel volume to be injected into the engine based on relevant engine parameters and characteristics of a default fuel type. A default mass fuel flow rate is derived from the default fuel volume and relevant engine parameters. The actual mass fuel flow rate into the engine is inferred from the mass air flow rate into the engine and the exhaust gas air-to-fuel ratio, which is determined using a wide range oxygen sensor. A fuel correction factor is calculated from the default mass fuel flow rate and the inferred mass fuel flow rate. The fuel correction factor is used to increment or decrement the default fuel volume in a subsequent fuel injection cycle thereby incrementing or decrementing the inferred mass fuel flow rate toward the default mass fuel flow rate.

Dependencies are inferred from the claim text.