System for sensing and controlling fuel gas constituent levels

A control system for use with an engine, the control system comprising:

• a plurality of micro-sensors mounted in a single micro-chamber configured to hold each of a successive portion of a mixture of gaseous fuel at substantially zero velocity for a period of time, each of the plurality of micro-sensors being configured to sense a characteristic of a mixture of gaseous fuel introduced into the micro-chamber;
• a plurality of resistive heating elements associated with each of the plurality of micro-sensors, each of the plurality of resistive heating elements being configured to implement a different temperature level at each of the plurality of micro-sensors;
• and
• a microprocessor configured to:
• determine a thermodynamic property of the mixture of gaseous fuel at the different temperature levels at each of the micro-sensors as a function of the characteristic sensed by each micro-sensor;
• correlate the thermodynamic property to a fuel gas composition of the mixture of gaseous fuel;
• and
• control an amount of at least one constituent in the mixture of gaseous fuel and an operating parameter of the engine as a function of the fuel gas composition determined by the correlation.

A method of controlling an engine, comprising:

• diverting successive portions of a mixture of gaseous fuel being supplied to the engine into a micro-chamber;
• temporarily holding each of the successive portions in a substantially still condition within the micro-chamber;
• heating each of a plurality of micro-sensors to a different temperature level at the same time at a plurality of different spaced locations within the micro-chamber;
• determining an overall thermal conductance for each successive portion of the mixture of gaseous fuel;
• and
• selectively adjusting at least one of a level of a constituent present in the mixture of gaseous fuel and a control parameter of the engine based on the thermal conductance.