Temperature Measuring Method

Patent metadata

Field	Value
Publication number	US-2017069925-A1
Application number	US-201615242143-A
Country	US
Kind code	A1
Filing date	Aug 19, 2016
Priority date	Sep 4, 2015
Publication date	Mar 9, 2017
Grant date	—

Abstract

A fuel cell system comprising a controller, a temperature sensor that has a physical presence in a conduit within the system to measure the temperature of the fluid at a point within the conduit (T g ) and a wall temperature sensor for sensing a temperature of a wall of the conduit (T w ). The controller takes T g and T w as inputs and applies an equation with known constants to calculate measurement error of T g based on the local flow temperature and geometry and arrives at a calculated temperature. The equation may be applied iteratively until the difference between the calculated temperature and T g is below an acceptable value when the calculated temperature can then be assumed to be an accurate representation of the actual gas temperature at the T g measurement point. The direction of calculation is controlled by the relative difference between T g and T w .

First claim

1 . A fuel cell system comprising:
a controller; a temperature sensor that has a physical presence in a conduit within the system; and a wall temperature sensor for sensing a temperature of a wall of the conduit; the controller operative to iteratively apply a thermal model to calculate a predicted temperature value that is, based on temperature values measured using the temperature sensor in the conduit and the wall temperature sensor, expected to be measured; wherein, when in an iterative step the predicted temperature value does not fulfil an interrupt criterion, an input temperature value used in a next iterative step is altered based on a difference between the temperatures measured by the sensors.

2 . A fuel cell system as claimed in claim 1 , wherein in a first iteration step the input temperature is the temperature measured using the sensor in the conduit.

3 . A fuel cell system as claimed in claim 1 , wherein the controller is arranged to reduce the input temperature value for use in the next iterative step if the temperature value measured using the temperature sensor in the conduit is larger than the temperature value measured by the wall sensor and/or increase the input temperature value for use in the next iterative step if the temperature value measured using the temperature sensor in the conduit is smaller than the temperature value measured by the wall sensor.

4 . A fuel cell system as claimed in claim 1 , wherein a first alteration of the input temperature value is larger than a second alteration, wherein the first alteration is undertaken in an earlier iterative step than the second alteration.

5 . A fuel cell system as claimed in claim 1 , wherein said interrupt criterion is fulfilled:
when the predicted temperature value falls within a predetermined temperature range of or below the temperature value measured using the sensor in the conduit in cases where the temperature value measured using the temperature sensor in the conduit is larger than the temperature value measured by the wall sensor; and/or when the predicted temperature value falls within a predetermined temperature range of or above the temperature value measured using the sensor in the conduit in cases where the temperature value measured using the temperature sensor in the conduit is smaller than the temperature value measured by the wall sensor.

6 . A fuel cell system as claimed in claim 1 , wherein said interrupt criterion is fulfilled when a predetermined number of iterative steps has been performed and/or when a predetermined time permitted for the calculation has elapsed.

7 . A fuel cell system as claimed in claim 1 , wherein a temperature value input in a final iterative step performed is output as a corrected temperature of a gas flowing in the conduit.

8 . A fuel cell system as claimed in claim 7 , further configured to use the corrected temperature for altering an operating parameter of the fuel cell system.

9 . A fuel cell system as claimed in claim 8 , wherein the operating parameter controlled is the temperature and/or the mass flow rate of the gas inlet to an anode and/or cathode of a fuel cell.

10 . A fuel cell system as claimed in claim 1 , wherein one or both temperature sensors are thermocouples.

11 . A method of determining a temperature in a conduit in a fuel cell system comprising:
measuring a temperature in the conduit using a sensor that has a physical presence in the conduit; measuring a temperature of a wall of the conduit using a wall temperature sensor; in a controller calculating a predicted temperature value basd on the measured temperature values by iteratively applying a thermal model; wherein, when in an iterative step the predicted temperature value does not fulfil an interrupt criterion, an input temperature value used in a next iterative step is altered based on a difference between the temperatures measured by the sensors.

Assignees

• Ceres Ip Co Ltd

Inventors

• Barari Farzad
• Barnard Paul
• Morgan Robert

Classifications

• G01K7/42

  Circuits effecting compensation of thermal inertia; Circuits for predicting the stationary value of a temperature · CPC title

• H01M8/04992 Primary

  characterised by the implementation of mathematical or computational algorithms, e.g. feedback control loops, fuzzy logic, neural networks or artificial intelligence · CPC title

• H01M8/04335

  of cathode reactants at the inlet or inside the fuel cell · CPC title

• G01K1/026

  arrangements for monitoring a plurality of temperatures, e.g. by multiplexing · CPC title

• G01K13/02 Primary

  for measuring temperature of moving fluids or granular materials capable of flow · CPC title