一种喷口控制的多目标约束设计方法

A Constrained Multi-objective Design Method for Nozzle Control

为克服试凑法在控制回路参数优化中的局限性,针对涡扇发动机在加力状态易出现喷口摆动的不协调现象,考虑喷口双环控制结构工作特点,采用按需正向设计策略,按照控制系统时域、频域性能指标设计要求,制定兼顾频域、时域性能要求的内、外环协调控制的设计目标准则,提出一种喷口控制的多目标约束的差分进化内外环控制参数自整定优化设计方法,在双转子涡扇发动机非线性模型上进行闭环控制系统仿真验证。结果表明:在飞行高度从0增加到10 km、飞行马赫数从0加速到0.9的起飞和爬升状态进入加力过程以及平飞中保持飞行马赫数不变的关断加力过程中,发动机未出现喷口摆动等现象,涡轮落压比最大相对误差不大于1.5%,喷口闭环控制系统具有期望的伺服跟踪和抗飞行条件变化干扰能力。

To overcome the limitations of the trial-and-error method in optimization of control loop parameters,and to address the issue of nozzle oscillation in turbofan engines during the afterburning state,taking into account the working characteristics of the nozzle dual loop control structure,an on-demand forward design strategy was adopted to meet the design requirements of the system's timedomain and frequency-domain performance indicators.A design objective criteria for coordinated control of the inner and outer loops,which takes into account both time-domain and frequency-domain performance requirements,was developed.A constrained multiobjective differential evolution inner and outer loop control parameter self-tuning optimization design method for nozzle control was proposed,and the closed-loop control system simulation verification on a nonlinear model of a dual rotor turbofan engine was conducted.The results show that in the process of afterburning initiation during the takeoff and climb conditions with flight altitude increasing from 0 km to 10 km,flight Mach number accelerating from 0 to 0.9,and in the process of afterburning shutting down during level flight with constant flight Mach number,the engine did not exhibit nozzle oscillation or other phenomena.The maximum relative error of the turbine pressure ratio was not greater than 1.5%.The nozzle closed-loop control system has the expected servo tracking and flight condition disturbance-resistant ability.