A new schedule method for compact propulsion system model

Abstract

The PSC (Performance Seeking Control) based on CPSM (Compact Propulsion System Model) has been verified by NASA. However, the CPSM has poor accuracy at off-design points. Therefore, a new basepoint schedule method is proposed to improve the CPSM accuracy at off-design points. At the off-design point, the thermodynamic parameters which is a function of temperature is an importance factor that influence the accuracy of model based on parameter corrections. Therefore, the temperature of fan inlet is taken into account during scheduling the basepoint vector. The simulations have shown that the accuracy of CPSM is at its best when the engine operates at a point where the temperature of the fan inlet is equal to the one of the basepoint. With the increase or decrease of the temperature of the fan inlet, the modeling errors of CPSM will increase. The simulations also demonstrate that the relative errors of the improved CPSM decrease significantly compared to those of the conventional CPSM at the off-design point.