Design of Fault Tolerant Control Laws for Jet Engines

Abstract:

Full Authority Digital Electronic Control (FADEC) system is common in all modern jet engines. In jet engine, the simplest control system is to produce desired engine thrust by changing the fuel flow. Since in flight engine thrust measurement is practically not possible, engine low pressure shaft rotational speed (N1/NL), engine pressure ratio (EPR), or exhaust jet temperature (EJT) has been effectively used as an indicator of the engine thrust. In this paper, the model used is twin spool turbofan engine. If any fault occurs in N1 sensor, the entire engine operation will be affected. Since there exists a unique aerodynamic relationship among the spool speeds, if any fault occurs in N1 sensor, engine thrust can be controlled with a certain amount of degradation using high pressure spool speed (N2/NH).Both soft and hard failures are detected using kalman filter, range, rate and comparison techniques. The effectiveness of the proposed approach is demonstrated by means of simulations.

• Periodical: Applied Mechanics and Materials (Volume 367)
• Pages: 96-100
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.367.96
• Online since: August 2013
• Authors: Rachel Francis Sneha, J.S. Mija
• Keywords: Fault Detection, High Pressure Shaft Rotational Speed (N2), Jet Engine, Kalman Filter (KF), Low Pressure Shaft Rotational Speed (N1), Sensor

References

[1] H. Austin Spang III, H. Brown, Control of jet engines, Control Engineering Practice 7 (1999), pp.1043-1059.

DOI: 10.1016/s0967-0661(99)00078-7

[2] Kapadi, Yadav and Pashilkar, Aero-thermodynamic model for digital simulation of turbofan engine, proceedings of GT 2005 ASME turbo expo (2005).

DOI: 10.1115/gt2005-68248

[3] Vivek Sanghi, B. K Lakshmanan and R. Rajasekaran, Aerothermal model for real time digital simulation of a mixed flow turbofan engine, Journal of propulsion and power, vol. 17, No. 3, May- June 2001, pp.629-634.

DOI: 10.2514/2.5789

[4] M. Harefors, Application of H infinity robust control to the RM12 jet engine, Control Eng. Practice vol 5, No. 9, pp.1189-1201, (1997).

DOI: 10.1016/s0967-0661(97)84358-4

[5] Rolf Isermann, Process fault detection based on modeling and estimation methods: A survey, Automatica, vol. 20, No 4, pp.387-404, (1984).

DOI: 10.1016/0005-1098(84)90098-0

[6] Walter.C. Merril, Sensor failure detection for jet engines, NASA Lewis Research Center, (1988).

[7] Heredia, Ollero, Bejar, Mahtani, Sensor and Actuator Fault Detection in Small Autonomous Helicopters,. Mechatronics 2008, 18, 90-99.

DOI: 10.1016/j.mechatronics.2007.09.007

[8] T. Kobayashi and D. Simon, Application of a bank of Kalman filters for Aircraft Engine Fault Diagnostics, Tech. Rep. TM-2003-212526, NASA, (2003).

DOI: 10.1115/gt2003-38550

[9] Jin Jians, Fault tolerant Control System – An introductory (overview), Acta Automatica Sinica, vol 31, No 1, (2005).

[10] Ai He, Daoliang Tan, Xi Wang, A Fault-tolerant Control Approach for Aircraft Engine Using a Bank of LMI-based UIO Filters, International Conference on Electronics, Communication and Control, 2011, p.1206 – 1209.

DOI: 10.1109/icecc.2011.6066717