Control Strategies for Safe Diesel Particulate Filter Uncontrolled Regeneration during Idle

Abstract

For diesel particulate filter (DPF) drop-to-idle uncontrolled regeneration, a regular regeneration is initiated following a vehicle stop while the engine switches to idle. The increase in oxygen concentration and the decrease in exhaust flow rate can result in a sharp exotherm in the filter and high temperature to damage the substrate. In this paper, control solutions for the idle thermal protection of the filter was proposed and validated experimentally. At high idle speed of 2200rpm, increasing exhaust gas recirculation (EGR) combined with intake throttling was a practical way to reduce available oxygen content to control the exothermal reaction rate. A much lower peak temperature was obtained for safe DPF regeneration during idle. The research would provide based information for optimizing the regeneration management strategy in order to avoid DPF failure in real world operation.