Free piston linear engine and its control systems
- 1. A REVIEW ON FREE PISTON LINEAR ENGINE AND ITS CONTROL SYSTEM BY: SHAFEEQUR RAHMAN S.I SURYA KANDHASWAMYT Dr P. GOPAL Department of Automobile Engineering ANNA UNIVERSITY BHARADHIDASAN INSTITUTE OF TECHNOLOGY(BIT) CAMPUS TIRUCHIRAPPALLI-620024
- 2. CONTENTS • Introduction • Free-piston engine basics • Operating principle • Piston configuration • Single piston • Dual piston • Opposed piston • Experimental setups • Piston dynamics and control • Starting • Misfiring • Applications of FPLE • Conclusion • References
- 3. Introduction • FPLE is nothing but an engine works without crankshaft • Instead of crankshaft , here an turbine and linear alternator is used to convert the rotary motion into reciprocatory motion • This crank less engine reduce the losses due the crankshaft
- 5. 1. It includes a single-piston, cylinder, and rebound device 2.The single-piston FPLE is mechanically simple with high controllability when compared to other FPLEs 1. It consists of two combustion chamber and a dual-piston 2.This engine eliminates the need for a rebound device, as the working piston provides the work to drive the compression process 3. In the other cylinder, which allows a simple and more compact device with higher power to weight ratio 1. It consists of two single piston units with a single combustion Chamber 2. Its pistons are synchronized by mechanical linkages to eliminate mechanical vibration, which is not found on any other linear engines 3. A shared combustion chamber also reduces heat losses. PISTON CONFIGURATION Single piston. Dual piston. Opposed piston.
- 6. Experimental systems • Single piston engine with linear alternator • Opposed piston engine setup • Dual piston engine setup
- 7. PISTON DYNAMICS AND CONTROL • Timing Control • Starting/ Restarting Control • Misfire Control • PistonTDC Control
- 8. Applications of FPLE • FPLEs decrease heat transfer loss in the cylinder by increasing piston acceleration, compared with conventional engines • The implementation of springs in FPLEs shows benefits for increasing piston velocity and engine performance. • In addition to benefit of piston dynamics, published results show that the thermal efficiency of FPLEs is higher than that of conventional engines.
- 9. Applications of FPLE (cont…) • the simulation results of FPLEs show benefits for reducing temperature-dependent emissions (NO) because the in cylinder gas temperature of FPLEs is generally lower than that of conventional engines. • The variable compression ratio in FPLEs is a great benefit for combustion. • By changing the compression ratio, FPLEs can optimize the combustion process and operate with various kinds of fuels and HCCI combustion. • A free-piston engine can not only be operated as a conventional internal combustion engine. It can also be integrated with a linear alternator to generate electric power • The electric power can be optimized by adjusting parameters such as piston assembly mass, ignition timing, equivalence ratio, electrical resistance, and air gap.
- 10. Conclusion • In this paper, we have reviewed on FPLEs with varied designs and operating features. • For piston stroke type, two-stroke FPLEs are most-commonly investigated and developed because of their advantages in structure and control. • Much research has shown that a linear alternator with a high efficiency • power source is an excellent power-unit candidate for HEVs.With the potential offered by high- efficiency linear alternators in FPLEs, we expect integrated systems to be further developed and applied in the near future.
- 11. References • Mikalsen R, Roskilly AP. A review of free-piston engine history and application. ApplTherm Eng 2007; 27:2339–52. • Mikalsen R, Roskilly AP.The control of a free-piston engine generator. Part 1: fundamental analysis. Appl Energy 2010; 87:1273–80. • Goertz M, Peng L. Free piston engine its application and optimization. SAE paper 2000-01-0996; 2000. • Kosaka H, AkitaT, Moriya K, Goto S, HottaY, UmenoT, et al. Development of free piston engine linear generator system part 1 – investigation of fundamental characteristics. SAE paper 2014-01-1203; 2014. • Blarigan PV. Free-piston engine. US patent no. 6199519 B1; March 13, 2001. • Mikalsen R, Roskilly AP.The fuel efficiency and exhaust gas emissions of a low heat rejection free-piston diesel engine. Proc IMech Part A: J Power Energy 2009; 223:379–84. • Blarigan PV. Advanced internal combustion electrical generator. In: Proceedings of the 2001 DOE hydrogen program review. p. 1–16. • Wakabayashi R,Takiguchi M, Shimada T, MizunoY,Yamauchi T.The effects of crank ratio and crankshaft offset on piston friction losses. SAE paper 2003-010983;2003. • Farmer HO. Free piston compressor engines. Proc Inst Mech Eng 1947; 156:253–71. • Ostenberg P. Electric generator. US patent 2362151 A; 1944.
- 12. ThankYou