Systems and methods for controlling turbocharger operation by maintaining a virtual turbocharger speed calculation using airflow parameters in the context of an engine. An example uses a turbocharger speed estimator, an energy observer, and an energy controller. Optimization of turbocharger speed control, including avoidance of overspeed, while reducing wastegate actuation, can be achieved using a predictive control algorithm.

Methods and systems are provided for restarting an engine following an engine idle-stop. In one example, a method may include, prior to an engine restart following an idle-stop, adjusting a spark ignition timing based on an estimation of a fuel-air equivalence ratio (phi) and an estimation of a cylinder turbulence. Optimal spark ignition timing based on estimated phi and cylinder turbulence during engine restart may result in stabilized combustion and a torque output sufficient to at least partially relieve demand on the starting device.

A heating system includes at least one electric heater disposed within a fluid flow system and a control device that is configured to determine a temperature of the at least one electric heater based on a model, at least one fluid flow system input, and at least one heater input. The at least one heater input includes at least one physical characteristic of the heating system, the at least one physical characteristic includes at least one of a resistance wire diameter, a heater insulation thickness, a heater sheath thickness, a conductivity, a specific heat and density of the material of the heater, an emissivity of the heater and the fluid flow pathway, and combinations thereof. The control device is configured to provide power to the at least one electric heater based on the temperature of the at least one electric heater.

The invention relates to a method (200) for operating an internal combustion engine (110) having at least one catalytic converter (122), wherein control interventions of a lambda control for controlling an exhaust gas composition of the internal combustion engine are deactivated, comprising ascertaining a current exhaust gas composition upstream of the at least one catalytic converter (122), determining a current oxygen fill level of the at least one catalytic converter (122) on the basis of the ascertained current exhaust gas composition, ascertaining (210) a planned control intervention on a composition of an air-fuel mixture supplied to the internal combustion engine (110) on the basis of the determined current oxygen fill level of the at least one catalytic converter, ascertaining a current exhaust gas composition (123) downstream of the at least one catalytic converter (122), ascertaining a future exhaust gas composition (123) downstream of the at least one catalytic converter (122) resulting on the basis of an air-fuel mixture already supplied to the internal combustion engine (110), and reactivating the lambda control and specifying (260) a control intervention to be carried out as a function of the planned control intervention and the current exhaust gas composition (123) downstream of the at least one catalytic converter (122), and/or as a function of the planned control intervention and the future exhaust gas composition. Furthermore, a processing unit (130) and a computer program for carrying out such a method (200) are proposed.

A method for operating an injection valve by ascertaining an opening time and/or closing time of the injection valve on the basis of a sensor signal. The method includes: providing an analysis point time series by sampling a sensor signal of a sensor of the injection valve; using a nonlinear, data-based first submodel in order to obtain a first model output on the basis of the analysis point time series; using a linear, data-based second submodel in order to obtain a second model output on the basis of the analysis point time series; ascertaining the opening time and/or closing time as a function of the first and second model outputs.

Methods and systems using model based and iterative calculations of mass flow throughout an internal combustion engine system. A secondary air injection valve is provided to selectively allow intake air to pass to the exhaust side of the engine system to aid in exothermic reaction with exhaust gasses exiting the engine for various purposes. The iterative calculations of mass flow include estimation of the mass flow through the secondary air injection valve.

A system may include virtual sensors representative of operation of different portions of a tangible system. The virtual sensors may receive measured characteristics of the tangible system and may separately output values representative of operation of a common component of the tangible system based on the one or more measured characteristics input into each virtual sensor. A controller may receive the output values from the virtual sensors and determine a state of the common component by comparing the first output value with the second output value.

A method and system is provided for correcting fueling commands. For example, the method and system may calibrate an engine operating in a steady-state mode by determining a plurality of accuracy errors associated with a fueling rate based on a plurality of sensor measurements. The method and system may determine fueling rate correction data during on-line operation of the engine based on the plurality of accuracy errors. The on-line operation of the engine may comprise operating the engine in a transient mode at a first period of time and a steady-state mode at a second period of time. The method and system may control at least one fueling valve during operation of the engine using a corrected fueling command. The corrected fueling command is based on the fueling rate correction data.

A system and method for dynamically deactivating engine cylinders of an engine equipped with a cylinder deactivation system, where the system and method control torsional vibration in the engine while deactivating cylinders using a computer programed with a desired firing density and a controlled range of engine vibration frequencies. The computer dynamically determines a cylinder firing pattern that provides the desired firing density while optimizing a cost function norm in the controlled range of engine vibration frequencies. The cylinder deactivation system in the engine is then controlled using the determined cylinder firing pattern.

A method for the model-based open-loop and closed-loop control of an internal combustion engine includes the steps of: during stationary operation, switching takes place cyclically from the normal operation to an exploration operation, wherein in the exploration operation, an exploration measure of quality (J/EXP) is calculated in accordance with combustion model and variance (VAR) thereof, wherein the exploration measure of quality (J/EXP) is set as essential for the operating point of the internal combustion engine, wherein on the basis of the operating variables of the internal combustion engine combustion model is adapted, and wherein switching back to normal operation takes place.