Methods and systems that monitor an actuator state of wear. One or more observations are made as to one or more extremum positions of the actuator to determine a reference extremum position when the actuator is not worn. As the actuator becomes worn, the difference between a present extremum position and the reference is used to monitor actuator wear. Actuator wear may be observed to identify or predict a need for maintenance or replacement, and/or may be used in determining health impacts of control system solutions.

A nonlinear disturbance rejection control apparatus and method for electronic throttle control systems are invented to control the electronic throttle system and to achieve a continuous finite-time disturbance rejection control goal. A control sub-apparatus and method are proposed with an observing sub-apparatus and method for controlling the opening angle of an electronic throttle valve. A mathematical model of the electronic throttle system is analyzed and a control-oriented model is presented with the formation of a lumped disturbance. With combination of the continuous terminal sliding mode control method and the output feedback control method, based on the finite-time high-order sliding mode observer, the preferred control performance is guaranteed, where both the dynamic and static performance of the system is effectively improved.

To keep medium purification efficiency at a high level and prevent deterioration of emission performance. An aspect of the present invention includes: a downstream equivalence ratio calculation unit that calculates a catalyst downstream exhaust gas equivalence ratio by using a catalyst statistical model that receives at least a detection value of an air-fuel ratio sensor on an upstream side of a catalyst and outputs a catalyst downstream exhaust gas equivalence ratio; an oxygen output calculation unit that calculates an output value of an oxygen sensor by using an oxygen sensor statistical model that receives the catalyst downstream exhaust gas equivalence ratio and outputs an output value of the oxygen sensor on the downstream side of the catalyst; a downstream equivalence ratio correction unit that corrects the catalyst downstream exhaust gas equivalence ratio calculated by the downstream equivalence ratio calculation unit based on a calculation result of the oxygen output calculation unit and the detection value of the oxygen sensor; and an air-fuel ratio control unit that controls an air-fuel ratio of an air-fuel mixture of an internal combustion engine based on the corrected catalyst downstream exhaust gas equivalence ratio and air-fuel ratio target value.

Methods and systems that monitor an actuator state of wear. One or more observations are made as to one or more extremum positions of the actuator to determine a reference extremum position when the actuator is not worn. As the actuator becomes worn, the difference between a present extremum position and the reference is used to monitor actuator wear. Actuator wear may be observed to identify or predict a need for maintenance or replacement, and/or may be used in determining health impacts of control system solutions.

New and/or alternative approaches to engine performance control that can account for the need to robustly monitor performance and/or operation of the physical plant and actuators thereof, while avoiding or limiting performance degradation. Model predictive control (MPC) or other control configuration such as proportional-integral-derivative control may be used to control the system by identifying a performance optimized control solution. In some examples, a modification to the performance optimized solution analysis is made to weight control solutions in favor of robust monitoring conditions. In other examples, the performance optimized solution is post-processed and modified to favor robust monitoring conditions.

The speed of a turbocharger may be estimated using data from sensors that are readily available in most engine management systems. In some cases, a pressure measurement from a MAP sensor may be used, in combination with one or more computational models, to provide an efficient, lower cost estimate of turbo speed that can be used to control operation of the engine and/or the turbocharger.

An engine system for a vehicle includes an internal combustion engine having an exhaust gas outlet, an exhaust system having a three-way catalyst and a switch-type post oxygen sensor, and an engine control module that controls the engine system. The engine control module includes a first control logic for estimating a three-way catalyst oxygen storage capacity based on a plurality of measured inputs, a second control logic for estimating aging effects of the switch-type post oxygen sensor, and a third control logic that calculates a filtered estimated three-way catalyst oxygen storage capacity for the three-way catalyst.

An internal combustion engine is provided. The internal combustion engine includes a control device, and at least one injector for liquid fuel. The injector(s) can be controlled by the control device via an actuator control signal. The injector(s) include an injector outlet opening for the liquid fuel which can be closed by a needle. A sensor is also provided for measuring a measurement variable of the injector(s). The sensor is or can be in a signal connection with the control device. An algorithm is stored in the control device, which algorithm calculates a state of the injector(s) based on input variables and an injector model, compares the state calculated via the injector model with a target state, and produces a state signal in accordance therewith. The state signal is characteristic of a change in the state of the injector(s) that occurs during intended use of the injector(s) and/or an unforeseen change in the state of the injector(s). The input variables include at least the actuator control signal and the measurement values of the sensor. A method for operating such an internal combustion engine and an injector is also provided.

An internal combustion engine is provided. The internal combustion engine includes a control device, and at least one injector for liquid fuel. The injector(s) can be controlled by the control device via an actuator control signal. The injector(s) include an injector outlet opening for the liquid fuel which can be closed by a needle. A sensor is also provided for measuring a measurement variable of the injector(s). The sensor is or can be in a signal connection with the control device. An algorithm is stored in the control device, which algorithm calculates a state of the injector(s) based on input variables and an injector model, compares the state calculated via the injector model with a target state, and produces a state signal in accordance therewith. The state signal is characteristic of a change in the state of the injector(s) that occurs during intended use of the injector(s) and/or an unforeseen change in the state of the injector(s). The input variables include at least the actuator control signal and the measurement values of the sensor. A method for operating such an internal combustion engine and an injector is also provided.

An exhaust gas after-treatment system for an internal combustion engine includes a selective catalyst reduction on filter (SCRF) exhaust gas after-treatment device in communication with exhaust gases from the internal combustion engine and having treated exhaust gas output. An oxides of nitrogen (NOx) sensor is coupled to treated exhaust gases and has a NOx sensor output signal that is NOx and ammonia (NH.sub.3) cross-sensitive. A closed loop observer (CLO) is operatively coupled to receive the NOx sensor output signal and provides a NOx concentration signal to an electronic control unit operatively associated with the exhaust gas after-treatment system and the internal combustion engine. CLO output at least includes an exhaust gas NOx concentration estimate and the ECU is arranged to be operable upon the NOx concentration estimate to control exhaust gas after-treatment system and internal combustion engine to effect an overall reduction in actual NOx concentration with the exhaust gases.