Design of a Control Power System Based on Temperature, Mean Effeetive Cycle Pressure, and Piston Speed for Speed Response Improvement of Stirling Engines

The main reason for the slow response of stirling engine with respect to power requirement supply is that the system energy supply is provided from wall to the working gas inside the cylinder. On contrary to most control systems, in stirling engines, actuator has the highest lag time, since energy transfer from the wall is taking place very slowly. In this article, increasing the reaction speed of stirling engine with respect to the required power is considered. Also, besides the temperatare and pressure control inputs, a piston speed is also taken into accunt. As a result, control system is considered as a constant pressure and based on needed demand, the required parameters are calculated first from power-speed tables. At first, this speed is provided by an auxilary eletrical DC motor. Then, by comparing the output signal with the required output, the controlling commads are specified for pressure and gas temperature adjustments. In striling engine modeling, the isothermal assumption is eliminated in order to have a real behavior. The simulation of closed loop system and the designed controller show the effective increase in engine response speed. In this article, it is also shown that the control system is resistant, subjected to internal as wellas external disturabnes. These disturbances are in the form of changes in heat sink and system parameters. Since, torque is considered constant in a large speed interval, the engine efficiency will not be much affected.