A method for reducing exhaust pressure of vehicle compressed air powered engine
Compressed air powered engine is a type of zero-pollution engine, but its conversion efficiency is very low for its high pressure exhaust which causes much exergy loss. In this study, a control system was developed to reduce the exhaust pressure of vehicle compressed air powered engine. The control system is made up of a controller, a pressure sensor, a photoelectric encoder, an inlet solenoid valve, and an exhaust solenoid valve. The controller receives the pressure signal of compressed air in cylinder from the pressure sensor and receives crank angle signal from photoelectric encoder, calculates when the solenoid valves should be opened or closed, and passes control signals to the solenoid valves. The simulation results indicate that the exhaust pressure can be controlled to be near to surrounding pressure by using this control system, and the exergy loss in exhaust stage can be avoided.
A Study on Compressed Air Engine Based on Electronic Control of Injection
In the paper,the general design plan of a kind of four-stroke Compressed Air Engine controlled by ECU has been proposed.The hard ware for the control system in the compressed air engine is described on its designing,manufacturing and commissioning.Design and commissioning of the management system software in the compressed air engine is presented.Proper strategies are applied to control air intake as to control precisely and flexibly the injection timing and pulse width under different conditions.For the engine,the comprehensive engine test bench and test device are also built.The initial experiments on the bench indicate that the general plan is feasible and the design of hardware and software of the Electronic control unit(ECU) is designed reasonably,so it enables the Compressed air engine runs well under the ECU.
Enhancing energy generation by use of efficient control for hybrid energy systems
This paper presents the design of control strategies, their effectiveness and energy enhancement potential for solar/wind/diesel integrated energy systems, solar thermal-biomass air heaters and solar thermal heat-pump hybrid water heaters. Use of control systems for optimising the usage of renewable energy sources with conventional energy systems is discussed.