Method and system for regenerating particulate filter

Abstract

A particulate filter regeneration system regenerates a particulate filter provided in an exhaust line of an engine equipped with a turbocharger by burning matter trapped on the particulate filter by raising the temperature of exhaust gas at times that the particulate filter requires regeneration. The system has an electric motor functioning as an intake quantity regeneration portion capable of increasing the flow rate of compressed air without depending on the flow rate of exhaust gas flowing across a turbine of the turbocharger, a bypass line connecting an engine intake line upstream of the engine to a section of the exhaust line upstream of the particulate filter, a flow rate regulation valve regulating the flow rate in the bypass line, and a control portion controlling the electric motor and the flow rate regulator.

Description

TECHNICAL FIELD[0001]This invention relates to a method and system for regenerating a particulate filter provided to remove particulate matter from exhaust gas, specifically a method and system for regenerating a particulate filter by burning matter trapped on the particulate filter.BACKGROUND ART[0002]Most of automobiles using an internal combustion engine, such as a diesel engine or the like, are equipped with a particulate filter designed to clean up exhaust gas by trapping PM (particulate matter) in the exhaust gas. Particulate filters used in diesel engine automobiles are called DPFs, in particular. Since PM accumulated to a certain level clogs such DPFs, the DPFs are regenerated by burning PM by raising the temperature of exhaust gas (see Patent Document 1, for example).[0003]As mentioned above, in order to regenerate particulate filters such as DPFs, raising the exhaust gas temperature, namely increasing heat contained in the exhaust gas by supplying fuel to the engine is req...

AI Technical Summary

Benefits of technology

[0012]The method and system for regenerating a particulate filter according to the present invention can increase the amount of oxygen supplied to the particulate filter by increasing the flow rate of compressed air without depending on the flow rate of exhaust gas flowing across a turbine of a turbocharger, and delivering part of the compressed air to the particulate filter, bypassing the internal combustion engine, and thus, enables effective burning of matter trapped on the particulate filter. Particularly, if the compressed air bypassing the internal combustion engine is delivered to the exhaust line, immediately after the internal combustion engine, it can cause burning of unburned fuel, resulting in an increase in heat.

[0013]Further, regulation to reduce the energy loss that the exhaust gas suffers in the turbine, or in other words, regulation to reduce heat loss by reducing the work done by the exhaust gas in the turbine leads to an efficient rise in exhaust gas temperature.

Problems solved by technology

However, for efficient operation of the engine, the amount of fuel supplied to the engine is controlled to meet a predetermined air-fuel ratio, so that increasing heat contained in the exhaust gas at optional times is difficult.

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