This paper presents a single-lever control method based on Power Management System (PMS) and improved Twin Delayed Deep Deterministic Policy Gradient (TD3) algorithm for turboprop engines. In this approach, power level angle command, which is the single-lever command, is decoupled into controlled variable commands by PMS, and the controller based on improved TD3 algorithm can ensure that controlled variables track their commands rapidly and accurately. To achieve the optimal conversion relationship between different commands, an offline optimization process is used to design PMS. By optimization, specific fuel consumption and propeller efficiency are both improved after conversion. To deal with strong interactions between different control loops of a turboprop engine, TD3 algorithm which is a deep reinforcement learning algorithm is adopted. Two improvements which are the design method of observation state and prioritized experience replay are made to enhance the tracking accuracy. Simulation results show that improved TD3 algorithm can learn an optimal control policy to guarantee good control effect with fast response and small overshoot. The maximum settling time is less than 0.25s and the maximum overshoot is less than 0.1%. It also has a good robustness performance when the plant exists model uncertainties. The maximum fluctuations are less than 0.05%.
The active jet noise control received significant attention due to the little influence it has on the engine performance. The active jet noise control is a multivariable problem because it needs to achieve the simultaneous closed-loop control of jet noise and engine performance. Model predictive control (MPC) has great application potentials in the field of multivariable control of aero-engines, but the real-time performance of MPC is intractable. This paper proposed an active jet noise controller of a turbofan engine, based on explicit model predictive control (EMPC). An integrated model of turbofan engine and jet noise, which calculates the engine parameters and jet noise in real time, was established. The online computational burden of MPC was transferred to offline computation using multi-parametric quadratic programming (MPQP). To improve the efficiency of the online positioning algorithm, the sequence search method was replaced by a binary search tree. Step simulations were performed to test the effectiveness of the proposed controller. The results show that the proposed EMPC controller not only achieves the simultaneous control of jet noise and the turbofan engine, but also improve the real-time performance greatly.