The DPF software can be divided into three separate software control modules: the DPF Monitoring Module, the DPF Fuel Management Module and the DPF Air Management Module.
These three modules are controlled by a fourth software module called the DPF Matching Module. The Matching Module controls the operation of the other modules when an active regeneration request is received. The DPF Control Module is a subsystem of the DPF Matching Module.
DPF Fuel Management Module
The DPF fuel management module controls the following functions:
- Synchronization of four separate injections per working stroke and the amount of fuel injected (preliminary, main and two additional injections).
- Injection pressure and switching between three different injection calibration levels.
The above functions depend on the condition of the catalytic converter and DPF.
In addition to measuring the activity of the catalytic converter and DPF, the controlled injection determines the required injection level. The fuel management system calculates the amount of fuel and the timing of the four separate injections for each of the three injection pressure calibration levels, and also controls the switching between the levels.
Two additional injections are required to separate the functions of increasing the cylinder gas temperature and producing hydrocarbons. The first additional injection is used to generate higher cylinder gas temperatures while maintaining the same engine torque as during normal (non-regeneration) engine operation. The second additional injection is used to produce hydrocarbons by directing unburned fuel to the catalytic converter without increasing engine torque.
DPF Air Flow Control Module
The DPF air flow control module controls the following functions:
- EGR control system
- Boost pressure control system
- Intake air temperature and pressure control system
During active regeneration, EGR is disabled and the closed-loop activation of the boost pressure regulator is calculated. The air flow control module monitors the air pressure and temperature level in the intake manifold. This monitoring is necessary to achieve the correct conditions inside the cylinder for stable and reliable combustion of the additionally injected fuel.
(The article is based on information from the website LRman.ru)
The module controls the intake air temperature, actuating the EGR throttle valve and regulating the boost pressure.
DPF matching module
The DPF matching module, upon receiving a regeneration request from the control module, initiates and matches the following DPF regeneration requests:
- Disabling EGR
- Boost pressure control
- Increased engine load
- Control of air pressure and temperature in the intake manifold
- Fuel injection control
When the control module requests regeneration, the matching module requests EGR to be disabled and the boost pressure required for regeneration. It then waits for a feedback signal from the EGR system confirming that the EGR valve is closed.
When the EGR valve closes, the matching module initiates a request to increase engine load by controlling intake air temperature and pressure.
After receiving confirmation that the intake conditions are under control or that the calibration time has expired, the matching module goes into a waiting state when the driver releases the accelerator pedal. If this happens or the calibration time has expired, the matching module generates a request to control the fuel injection to increase the exhaust gas temperature.
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