三元触媒の動的応答特性を利用したガスエンジン空燃比制御の研究

抄録

The control methods of a gas engine are presented using response waveforms of an O₂ sensor through three-way catalysts under dynamic operation. Zirconia O₂ sensors were used to measure the response of three-way catalysts following stepchange in the engine air/fuel ratio. The concentration measurements at the catalysts' inlets and outlets were made by using the successive exhausts analyzers. In the dynamic behavior of three-way catalysts, the lean-to-rich or rich-to-lean step response of the O₂ sensor had a time lag. This time lag depends on the controlled condition of air/fuel ratio. Taking advantage of this response characteristic, the stable control of the air/fuel ratio and the low NO_x, CO, CH₄ emissions were achieved. The results of the control experiments demonstrate the availability of the new control methods.