Direct thrust control method for multi-companion vectoring engines

To address the requirements of modern aircraft for high maneuverability and strong countermeasure capability in complex tactical environments, and resolve the drawbacks of low accuracy and slow response in conventional indirect thrust control of engines, this paper proposes a direct thrust control method for multi-companion vectoring engines. First, a nonlinear component-level model consisting of one main engine and two companion engines is established, with refined modeling conducted for key components such as the bleed air system. To achieve accurate estimation of engine thrust, an on-board adaptive model based on the Unscented Kalman Filter (UKF) is designed. This model incorporates a steady/dynamic discrimination logic to on-line identify the engine’ s performance degradation parameters, thereby effectively suppressing the interference of flight dynamics on health assessment. On this basis, a data-driven Model-Free Adaptive Control (MFAC) strategy is further proposed, and a Multi-Input Multi-Output (MIMO) direct thrust controller is constructed to realize decoupled, rapid, and precise control of the thrust of the main and companion engines. Simulation results demonstrate that the designed on-board adaptive model can accurately track the actual state of the engine, and its thrust estimation results are highly consistent with the true values; the direct thrust controller responds rapidly, achieving stable and precise tracking of the commanded thrust under the conditions that the settling time of the main engine is less than 1 s and the overshoot is below 4%. This study provides an effective solution for the control system design of novel combined vectored-thrust engines and verifies the feasibility and potential of this scheme in improving engine control performance.