Control device of an engine

Patent metadata

Field	Value
Publication number	US-10309298-B2
Application number	US-201615217916-A
Country	US
Kind code	B2
Filing date	Jul 22, 2016
Priority date	Jul 29, 2015
Publication date	Jun 4, 2019
Grant date	Jun 4, 2019

Abstract

To improve the controllability of the feedback control of the boost pressure, an ECU comprises a valve control part that feedback controls a boost pressure of a turbocharger based on a deviation between a target boost pressure and an actual boost pressure, and a determination part that determines whether or not the exhaust state in an exhaust passage can achieve the target boost pressure, and the feedback control includes at least an integral term, and when the determination part determines the exhaust state cannot achieve the target boost pressure, the valve control part reduces the influence of the deviation on the calculation of integral term compared with that when the exhaust state can achieve the target boost pressure.

First claim

The invention claimed is:

1. A control system of an engine, the system comprising:
a turbocharger having a turbine that is provided to an exhaust passage and a compressor that is provided to an intake passage,
a turbine bypass passage for diverting exhaust around the turbine,
a wastegate valve that is provided to the turbine bypass passage for controlling a flow rate of the exhaust flowing in the turbine bypass passage, and
a control device executed on a processor including:
a valve control part, executed on the processor, for performing a feedback control of a boost pressure of the turbocharger based on a deviation between a target boost pressure and an actual boost pressure, and
a determination part, executed on the processor, for obtaining a target turbine flow rate that is a target value of the flow rate of the exhaust flowing to the turbine from the target boost pressure, for obtaining an exhaust total flow rate discharging from the engine, and for determining whether or not the exhaust total flow rate discharging from the engine in the exhaust passage is greater than or equal to the target turbine flow rate, such that the target boost pressure will be achieved, the target turbine flow rate being based on the target boost pressure,

wherein the feedback control includes at least an integral term, and when the determination part determines that the exhaust total flow rate is smaller than the target turbine flow rate such that the target boost pressure will not be achieved, the valve control part controls an opening degree of the wastegate valve so as to reduce an influence of the deviation on a calculation of the integral term compared to that when the exhaust total flow rate is greater than or equal to the target turbine flow rate such that the target boost pressure will be achieved.

2. The control system of the engine according to claim 1 ,
wherein the valve control part calculates the integral term that is a correction amount corresponding to an integrated value from a time integration of a driving force deviation of the compressor calculated from the boost pressure, and when the determination part determines that the exhaust total flow rate is smaller than the target turbine flow rate such that the target boost pressure will not be achieved, the valve control part stops the calculation of the integrated value of the driving force deviation.

Assignees

• Mazda Motor

Inventors

• Nishio Takafumi

Classifications

• F02D41/1401

  characterised by the control or regulation method (F02D41/1473, F02D41/1477 take precedence) · CPC title

• F02D2041/1409

  using at least a proportional, integral or derivative controller · CPC title

• F02B33/40

  of non-positive-displacement type · CPC title

• F02D41/0007

  for control of turbo-charged or super-charged engines (control of the pumps per se F02B37/12) · CPC title

• F02M35/10157

  Supercharged engines · CPC title