Method for estimating the temperature in an internal combustion engine

Abstract

A method and circuit are provided for estimating the temperature in an internal combustion engine. The method includes, but is not limited to the steps of providing a sensor resistor (RTD) in the internal combustion engine, the sensor resistor (RTD) having a predetermined resistance-temperature characteristic, and estimating the temperature based on the resistance-temperature characteristic. The method also includes, but is not limited to the steps of providing to the sensor resistor (RTD) a reference current signal (I1) so that a sensor voltage (VRTD) is established across the sensor resistor (RTD), generating a reference voltage signal (V2), comparing the established sensor voltage (VRTD) with the reference voltage signal (V2), modifying the reference current signal (I1) and reference voltage signal (V2) on the basis of the comparison outcome so as to minimize the difference between the sensor voltage (VRTD) and the reference voltage signal (V2), and calculating the resistance value of the sensor resistor (RTD) based on the reference voltage signal (V2) and reference current signal (I1).

Dependencies are inferred from the claim text.