Decentralized Feedback Control of Pumping Losses and NOx Emissions in Diesel Engines

2018 ◽  
Vol 140 (10) ◽  
Author(s):  
Rasoul Salehi ◽  
Jason Martz ◽  
Anna Stefanopoulou ◽  
Bruce Vernham ◽  
Lakshmidhar Uppalapati ◽  
...  
Keyword(s):  
Real Time ◽  
Diesel Engines ◽  
Test Procedure ◽  
Time Derivative ◽  
Time Estimation ◽  
Mean Value ◽  
Boost Pressure ◽  
Nox Emissions ◽  
Control Loops ◽  
Engine Model

A novel decentralized control architecture is developed based on a feedback from the pressure difference across the engine which is responsible for the pumping losses and the exhaust gas recirculation (EGR) flow in diesel engines. The controller is supplemented with another feedback loop based on NOx emissions measurement. Aiming for simple design and tuning, the two control loops are designed and discussed: one manipulates the variable geometry turbine (VGT) actuator and the other manipulates the EGR valve. An experimentally validated mean-value diesel engine model is used to analyze the best pairing of actuators and set points. Emphasis is given to the robustness of this pairing based on gain changes across the entire operating region, since swapping the pairing needs to be avoided. The VGT loop is designed to achieve fast cylinder air charge increase in response to a rapid pedal tip-in by a feedforward term based on the real-time derivative of the desired boost pressure. The EGR loop relies on a feedback measurement from a NOx sensor and a real-time estimation of cylinder oxygen ratio, χcyl. The engine model is used for evaluating the designed controllers over the federal test procedure (FTP) for heavy duty (HD) vehicles. Results indicate that the control system meets all targets, namely fast air charge and χcyl control during torque transients, robust NOx control during steady-state operation, and controlled pumping losses in all conditions.

Decentralized Feedback Control of Pumping Losses and NOx Emissions in Diesel Engines

2017 ◽  
Author(s):  
Rasoul Salehi ◽  
Jason Martz ◽  
Anna Stefanopoulou ◽  
Bruce Vernham ◽  
Lakshmidhar Uppalapati ◽  
...  
Keyword(s):  
Real Time ◽  
Diesel Engines ◽  
Test Procedure ◽  
Time Derivative ◽  
Time Estimation ◽  
Mean Value ◽  
Boost Pressure ◽  
Nox Emissions ◽  
Control Loops ◽  
Engine Model

A novel decentralized control architecture is developed based on a feedback from the pressure difference across the engine which is responsible for the pumping losses and the Exhaust Gas Recirculation (EGR) flow in diesel engines. The controller is supplemented with another feedback loop based on NOx emissions measurement. Aiming for simple design and tuning, the two control loops are designed and discussed; one manipulates the Variable Geometry Turbine (VGT) actuator and the other manipulates the EGR valve. An experimentally validated mean-value diesel engine model is used to analyze the best pairing of actuators and set points. Emphasis is given to the robustness of this pairing based on gain changes across the entire operating region, since swapping the pairing needs to be avoided. The VGT loop is designed to achieve fast cylinder air charge increase in response to a rapid pedal tip-in by a feedforward term based on the real-time derivative of the desired boost pressure. The EGR loop relies on a feedback measurement from a NOx sensor and a real-time estimation of cylinder oxygen ratio, χcyl. The engine model is used for evaluating the designed controllers over the federal test procedure (FTP) for heavy duty vehicles. Results indicate that the control system meets all targets, namely fast air charge and χcyl control during torque transients, robust NOx control during steady state operation and controlled pumping losses in all conditions.

Optimal Control of Complex Air-Path Systems for Advanced Diesel Engines

2009 ◽  
Author(s):  
Fengjun Yan ◽  
Benjamin Haber ◽  
Junmin Wang
Keyword(s):  
Optimal Control ◽  
Diesel Engines ◽  
Linear Quadratic Regulator ◽  
Mean Value ◽  
Diffusion Combustion ◽  
Linear Quadratic ◽  
Control Approach ◽  
Engine Model ◽  
Path System ◽  
Linearized Model

This paper describes a linear optimal control approach for advanced diesel engines equipped with complex air-path systems including a dual-loop exhaust gas recirculation (EGR) and a two-stage turbocharger. Such complex air-path systems are instrumental to achieve smooth and stable transient operation of diesel engines running advanced multiple combustion modes such as low temperature diffusion combustion (LTDC) and homogeneous charge compression ignition (HCCI). A mean-value engine model was developed to capture the main dynamics of the advanced air-path system. A linear quadratic regulator (LQR) optimal controller was designed based on a linearized model at a fixed operating point. Simulation results using a high-fidelity detailed GT-Power engine model show the effectiveness of the controller.

Real-Time Estimation of Intake O2 Concentration in Turbocharged Common-Rail Diesel Engines

2013 ◽  
Vol 6 (1) ◽  
pp. 237-245 ◽  
Author(s):  
Ivan Arsie ◽  
Andrea Cricchio ◽  
Cesare Pianese ◽  
Matteo De Cesare
Keyword(s):  
Real Time ◽  
Diesel Engines ◽  
Time Estimation ◽  
Common Rail ◽  
O2 Concentration ◽  
Real Time Estimation

A Real-Time Model of Crush Natural Gas Turbo Engine

2011 ◽  
Vol 58-60 ◽  
pp. 2511-2516
Author(s):  
Rong Di Yuan ◽  
Quan Quan Du
Keyword(s):  
Natural Gas ◽  
Real Time ◽  
Mean Value ◽  
Bench Test ◽  
Time Model ◽  
Electronic Throttle ◽  
Engine Model ◽  
Mean Value Model ◽  
Cng Engine ◽  
Turbo Engine

A new approach is presented in this paper in which a Crush Natural Gas (CNG) Turbo Engine model based on Mean Value Model and transient dynamics are included. The model could simulate engine speed, torque, dynamic load, electronic throttle, turbo, temperature and emission conditions. The model was downloaded and run in a HIL platform joint with Labview and a CNG engine ECU. Simulation results indicate that it acquires good balance between Real-time response and dynamic accuracy, besides good comprehensive running status parameters including dynamic, mechanic, thermo and combustion. The model made it possible for electronic engineers to begin their works earlier to find solutions for power loss, high working temperature of CNG engine with more flexibility and lower bench test expense.

Real-Time Estimation and Calibration of GLONASS Inter-Frequency Phase and Code Bias

2019 ◽  
Vol 73 (3) ◽  
pp. 746-762 ◽  
Author(s):  
Zhixin Yang ◽  
Hui Liu ◽  
Yidong Lou ◽  
Bao Shu ◽  
Longwei Xu ◽  
...  
Keyword(s):  
Real Time ◽  
Elevation Angle ◽  
Vertical Direction ◽  
Time Estimation ◽  
Calibration Method ◽  
Mean Value ◽  
Time Calibration ◽  
Calibration Methods ◽  
Code Bias ◽  
Frequency Phase

The frequency division multiple access (FDMA) strategy used in GLONASS causes inter-frequency phase bias (IFPB) and inter-frequency code bias (IFCB) between receivers from different manufacturers. The existence of IFPB and IFCB significantly increases the difficulties of fixing GLONASS ambiguity and limits the accuracy and reliability of GLONASS positioning. Moreover, the initial value of IFPB and IFCB may be unavailable or unreliable with the increasing number of receivers from different manufacturers in recent years. In this study, a real-time and reliable calibration algorithm of IFPB and IFCB based on multi-GNSS assistance is proposed by providing a fixed solution. Real-time IFPB rate and IFCB can be obtained using this algorithm without the initial IFPB and IFCB. The IFPB rate for all GLONASS satellites and IFCB for each GLONASS satellite are estimated due to different characteristics of IFPB and IFCB. IFPB calibration can be divided into constant and real-time IFPB calibrations to meet the different positioning requirements. Results show that constant IFPB rate has only 2 mm difference from the mean value of real-time IFPB rate. The IFPB rate and IFCB estimated by this algorithm have excellent stability, and the change in reference satellite cannot affect the results of IFPB rate and the stability of IFCB. The centimetre-level positioning results can be obtained using two calibration methods, and the positioning results with real-time calibration method are 10%–20% better than those with the constant calibration method. Under satellite-deprived environments, the improvements of multi-GNSS positioning accuracy with constant inter-frequency bias calibration gradually increase as the satellite cut-off elevation angle increases compared with GPS/BDS, which can reach up to 0·9 cm in the vertical direction.

scholarly journals Real-Time Estimation of Temperature Time Derivative in Inertial Measurement Unit by Finite-Impulse-Response Exponential Regression on Updates

Sensors ◽  
2020 ◽  
Vol 20 (5) ◽  
pp. 1299
Author(s):  
Alexander Kozlov ◽  
Ilya Tarygin
Keyword(s):  
Real Time ◽  
Impulse Response ◽  
Measurement Errors ◽  
Finite Impulse Response ◽  
Time Derivative ◽  
Time Estimation ◽  
Measurement Unit ◽  
Model Parameters ◽  
Navigation Systems ◽  
Sensor Output

We present a filtering technique that allows estimating the time derivative of slowly changing temperature measured via quantized sensor output in real time. Due to quantization, the output may appear constant for several minutes in a row with the temperature actually changing over time. Another issue is that measurement errors do not represent any kind of white noise. Being typically the case in high-grade inertial navigation systems, these phenomena amid slow variations of temperature prevent any kind of straightforward assessment of its time derivative, which is required for compensating hysteresis-like thermal effects in inertial sensors. The method is based on a short-term temperature prediction represented by an exponentially decaying function, and on the finite-impulse-response Kalman filtering in its numerically stable square-root form, employed for estimating model parameters in real time. Instead of using all of the measurements, the estimation involves only those received when quantized sensor output is updated. We compare the technique against both an ordinary averaging numerical differentiator and a conventional Kalman filter, over a set of real samples recorded from the inertial unit.

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