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DE-102014207199-B4 - Method and device for reducing the particulate emissions of an internal combustion engine, as well as a motor vehicle

DE102014207199B4DE 102014207199 B4DE102014207199 B4DE 102014207199B4DE-102014207199-B4

Abstract

Method for controlling an internal combustion engine, comprising the following steps: - Supplying fuel to a combustion chamber of the internal combustion engine; - Ignition of the fuel in the combustion chamber; and - Detect that the internal combustion engine should deliver a higher actual power output (14; 24); - Shifting the ignition timing to a later time (34) compared to the ignition timing (32, 36) at a static power demand (12, 16) when it is detected that the internal combustion engine is to deliver a higher actual power; characterized in that the step of shifting the ignition timing to a later time (34) compared to the ignition timing at a static power demand (32, 36) is only carried out at a predetermined speed.

Inventors

  • Hans-Juergen Farsch

Assignees

  • BAYERISCHE MOTOREN WERKE AKTIENGESELLSCHAFT

Dates

Publication Date
20260513
Application Date
20140415

Claims (10)

  1. A method for controlling an internal combustion engine, comprising the following steps: - supplying fuel to a combustion chamber of the internal combustion engine; - igniting the fuel in the combustion chamber; and - detecting that the internal combustion engine is to deliver a higher actual power output (14; 24); - retarding the ignition timing to a later time (34) compared to the ignition timing (32, 36) at a static power demand (12, 16) when it is detected that the internal combustion engine is to deliver a higher actual power output; characterized in that the step of retarding the ignition timing to a later time (34) compared to the ignition timing at a static power demand (32, 36) is only carried out below a predetermined rotational speed.
  2. Procedure according to Claim 1 , characterized by the step of increasing the fuel supply (44) to a combustion chamber of the internal combustion engine compared with the fuel supply at a static power demand (42, 46), while shifting the ignition timing to a later time (34) compared with the ignition timing (32, 36) at a static power demand.
  3. Procedure according to Claim 1 , characterized by increasing a torque reserve if it is detected that the internal combustion engine is to deliver a higher actual power output (14).
  4. Procedure according to Claim 2 , characterized in that the step of increasing the fuel supply (44) to the combustion chamber of the internal combustion engine is carried out only at a predetermined speed, compared to the fuel supply during a static power demand (42, 46).
  5. Procedure according to one of the Claims 2 or 4 , characterized in that the step of shifting the ignition timing to a later time (34) compared to the ignition timing at a static power demand (32, 36) and/or the step of increasing the fuel supply (44) to the combustion chamber of the internal combustion engine compared to a static power demand (42, 46) are only carried out under a predetermined power demand.
  6. Control device configured to control the fuel supply to an internal combustion engine and the ignition timing of the internal combustion engine, the control device being configured to shift the ignition timing to a later time (34) compared to the ignition timing at a static power demand (32, 36) when it is detected that the internal combustion engine is to deliver a higher actual power (14, 24), characterized in that the shifting of the ignition timing to a later time (34) compared to the ignition timing at a static power demand (32, 36) is only carried out below a predetermined maximum speed.
  7. Control device according to Claim 6 , characterized in that the control device is designed to increase the fuel supply to a combustion chamber of the internal combustion engine during the shifting of the ignition timing to a later time (34) compared with the ignition timing at a static power demand (32, 36) compared with the fuel supply at a static power demand (32, 36) (44).
  8. Control device according to Claim 7 , characterized in that the control device is designed so that the increase in the fuel supply (44) to the combustion chamber of the internal combustion engine, compared with the fuel supply (42, 46) at a static power demand (32, 36), is carried out only at a predetermined maximum speed.
  9. Control device according to one of the Claims 7 or 8 , characterized in that the control device is designed to allow the shifting of the ignition timing to a later time (34) compared to the ignition timing at a static power demand (32, 36) and/or the increase of the fuel supply (44) to the combustion chamber of the combustion engine The operation of the engine compared to the fuel supply (42, 46) under a static power demand (32, 36) is only carried out under a predetermined power demand.
  10. Motor vehicle with the control device according to one of the Claims 6 until 9 .

Description

The present invention relates to a method and a control device for reducing the particle emission of an internal combustion engine. The operating principle of an internal combustion engine is well understood by experts. Fuel and air are supplied to the combustion chamber of the engine through valves. Once the combustion chamber valves are closed and a piston is in the appropriate position, i.e., near top dead center, the fuel-air mixture in the combustion chamber is ignited. Depending on the load, the amount of fuel supplied to the combustion chamber and the ignition timing vary. Under dynamic load or during acceleration, a combustion engine emits more particles compared to a static load. The EU6c standard, expected to come into force in 2017, mandates stricter limits for particulate emissions from gasoline engines. These limits can only be met by certain vehicles through costly additional measures that significantly increase the vehicle's price. The patent documents DE 10 2005 058 864 A1 , DE 10 2013 204 901 A1 , DE 10 2011 111 226 A1 and DE 198 06 665 A1 Each shows operating procedures for internal combustion engines or motor vehicles. The invention therefore aims to create a method and a control device with which particle emissions are reduced. The object of the invention is achieved by a method according to claim 1, a control device according to claim 6, and a motor vehicle according to claim 10. The dependent claims describe preferred embodiments. The method can be further developed as described with regard to the device. The device can be further developed as described with regard to the method. A method for controlling an internal combustion engine comprises the steps of supplying fuel to a combustion chamber of the engine, igniting the fuel in the combustion chamber, and detecting that the engine is required to deliver higher actual power. According to the invention, the ignition timing is retarded compared to the ignition timing at a static power demand when it is detected that the engine is required to deliver higher actual power. When the engine is required to deliver higher actual power, it exhibits positive load dynamics and/or positive speed dynamics. During acceleration of the vehicle, more particles are produced than during a static power demand. The inventor of the present invention has recognized that retarding the ignition timing compared to the ignition timing at a static power demand can reduce particle emissions. The torque reduction resulting from retarding the ignition timing is compensated for by a compensating torque. The process further includes increasing the fuel supply to a combustion chamber of the internal combustion engine while simultaneously retarding the ignition timing compared to the ignition timing under static power demand. This increases the vehicle's fuel consumption. However, this is acceptable because acceleration phases are relatively short under normal operating conditions. The increased fuel supply adjusts the compensation torque. It is understood that the cylinder filling, or air supply, is increased proportionally with the fuel supply. Particulate reduction can be approximately 25%, depending on the driving cycle. The increase in fuel consumption can range from about 0.5% to 0.8%, again depending on the driving cycle. By retarding the ignition timing or adjusting the ignition angle, the smoothness of the combustion engine is impaired. This can be tolerated, as a driver or passenger will not notice the reduced smoothness during acceleration. The procedure can increase the torque reserve if it detects that the combustion engine is expected to deliver a higher actual power output and is therefore operating in a positive load and/or speed dynamic range. This is typically achieved by retarding the ignition timing to a later point that is optimal for the corresponding load case with regard to fuel consumption and/or smooth running, and by supplying more fuel to the combustion chamber and more air to the combustion engine. Once the combustion engine has returned to a stable operating state, the ignition timing can be gradually adjusted back to the optimal ignition timing for a static power demand. The ignition timing can be adjusted with The torque can be adjusted via a ramp from the delayed point in time to the optimal point in time for a static power demand. The compensation torque or torque reserve is reduced to the same extent. This reduces the number of particles emitted by the combustion engine during acceleration. The step of retarding the ignition timing compared to the ignition timing under a static power demand is only performed below a predetermined maximum engine speed. According to one interpretation, the step of increasing the fuel supply to the combustion chamber of the internal combustion engine, compared to the fuel supply under a static power demand, is only performed below a predetermined maximum engine speed. By retarding the ignition timing comp