Co-Surge Detection and Control for Bi-Turbo Engines with Experimental Evaluation

Thomasson, Andreas; Eriksson, Lars

doi:10.3182/20130904-4-jp-2042.00012

Cited by 2 publications

(2 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To avoid that the throttle closing after recovery pushes the system into surge again, the throttle closing after co-surge is rate limited u * thr,ff = max u thr,ff , u thr,ff (t − t s ) − k/t s (8) where t s is the sample time and k is the maximum retard rate. In addition to this, if the pressure drop over the throttle is very low when co-surge begins, only opening the throttle is not enough to quell the oscillation, see Thomasson and Eriksson (2013). In that case actuating the bypass valves are necessary.…”

Section: Co-surge Controlmentioning

confidence: 99%

“…The analysis results in a new controller that tries to force the turbo speeds together during co-surge. The controller takes ideas from Thomasson and Eriksson (2013), but uses a model based feedforward for the throttle, and wastegate actuation to increase stability and enable faster recovery from co-surge. The controller is evaluated both in simulation and test vehicle.…”

Section: Contributions and Outlinementioning

confidence: 99%

See 1 more Smart Citation

Co-surge in bi-turbo engines: Measurements, analysis and control

Thomasson

Eriksson

2014

Control Engineering Practice

Self Cite

View full text Add to dashboard Cite

In parallel turbocharged V-engines, with two separate air paths connected before the throttle, an oscillation in the flow can occur. If the compressor operates close to the surge line, typically during low speed and high load, and a disturbance alters the mass flow balance, the compressors can begin to alternately go into surge. This phenomenon is called co-surge and is unwanted due to high noise and risk for turbocharger destruction. Co-surge is measured on a test vehicle in a chassis dynamometer and the system analyzed and modeled using a mean value engine model. The investigation shows that the alternating compressor speeds have an important role in the prolonged oscillation. A reconstruction of the negative flow from measurements is made and compared to simulation results, showing similar amplitudes, and supports the model validation. A new co-surge detection algorithm is presented, suitable for a pair of sensors measuring either mass flow, boost pressure or turbo speed in the two air paths. Furthermore, a new controller is proposed that uses a model based feedforward for the throttle, together with wastegate actuation to force the compressor speeds together and improve balance at the recovery point. This has shown to be sufficient with moderate to high pressure ratios over the throttle, only for zero or very low pressure drop the use of bypass valves are necessary. The advantage of not opening the bypass valves is a smaller drop in boost pressure which also reduces the torque disturbance. The performance of the controller is evaluated both in simulation and in the test vehicle.

show abstract

Section: Co-surge Controlmentioning

confidence: 99%

Section: Contributions and Outlinementioning

confidence: 99%

Co-surge in bi-turbo engines: Measurements, analysis and control

Thomasson

Eriksson

2014

Control Engineering Practice

Self Cite

View full text Add to dashboard Cite

show abstract

Modeling and control of actuators and co-surge in turbocharged engines

Thomasson¹

2014

Self Cite

View full text Add to dashboard Cite

Paper 1 is reproduced here with permission from IFP Energies nouvelles Paper 2 is reproduced here with permission from IFAC Paper 3 is reproduced here with permission from Elsevier Paper 4 is reproduced here with permission from IFAC The cover: Photo of an electronic throttle, a pneumatic actuator, and a measurement of mass flows during co-surge, illustrating the main topics of the thesis. Typeset with L A T E X 2εPrinted by LiU-Tryck, Linköping, Sweden 2014 i AbstractThe torque response of the engine is important for the driving experience of a vehicle. In spark ignited engines, torque is proportional to the air flow into the cylinders. Controlling torque therefore implies controlling air flow. In modern turbocharged engines, the driver commands are interpreted by an electronic control unit that controls the engine through electromechanical and pneumatic actuators. Air flow to the intake manifold is controlled by an electronic throttle, and a wastegate controls the energy to the turbine, affecting boost pressure and air flow. These actuators and their dynamics affect the torque response and a lot of time is put into calibration of controllers for these actuators. By modeling and understanding the actuator behavior this dynamics can be compensated for, leaving a reduced control problem, which can shorten the calibration time.Electronic throttle servo control is the first problem studied. By constructing a control oriented model for the throttle servo and inverting that model, the resulting controller becomes two static compensators for friction and limp-home nonlinearities, together with a PD-controller. A gain-scheduled I-part is added for robustness to handle model errors. The sensitivity to model errors is studied and a method for tuning the controller is presented. The performance has been evaluated in simulation, in test vehicle, and in a throttle control benchmark.A model for a pneumatic wastegate actuator and solenoid control valve, used for boost pressure control, is presented. The actuator dynamics is shown to be important for the transient boost pressure response. The model is incorporated in a mean value engine model and shown to give accurate description of the transient response. A tuning method for the feedback (PID) part of a boost controller is proposed, based on step responses in wastegate control signal. Together with static feedforward the controller is shown to achieve the desired boost pressure response. Submodels for an advanced boost control system consisting of several vacuum actuators, solenoid valves, a vacuum tank and a vacuum pump are developed. The submodels and integrated system are evaluated on a two stage series sequential turbo system, and control with system voltage disturbance rejection is demonstrated on an engine in a test cell.Turbocharged V-type engines often have two parallel turbochargers, each powered by one bank of cylinders. When the two air paths are connected before the throttle an unwanted oscillation can occur. When the compressors operate close to the surge lin...

show abstract

Co-Surge Detection and Control for Bi-Turbo Engines with Experimental Evaluation

Cited by 2 publications

References 12 publications

Co-surge in bi-turbo engines: Measurements, analysis and control

Co-surge in bi-turbo engines: Measurements, analysis and control

Modeling and control of actuators and co-surge in turbocharged engines

Contact Info

Product

Resources

About