涡轮电推进系统建模及控制规律设计

Modelling and control schedule design of turboelectric propulsion system

关键词:  航空发动机  涡轮电推进系统  推进系统建模  差分进化算法  控制规律设计

Key words:  Aeroengine  Turboelectric propulsion system  Propulsion system modelling  Differential evolution algorithm  Control schedule design

摘要:

为了研究涡轮电推进系统的工作特性及控制规律设计方法，建立了涡轮电推进系统总体性能仿真模型。基于部件法建立了涵道风扇性能计算模型；基于电机效率图建立了发电机及电动机性能计算模型；基于面向对象的建模方法建立了电推进模块计算模型。将建立的电推进模块计算模型加入涡扇发动机部件级仿真模型中，构建了涡轮电推进系统的共同工作方程组，即其性能仿真模型。采用逆算法研究了不同几何参数控制规律下，涵道风扇推力调节时推进系统的工作特性。通过在性能仿真模型中添加推力平衡方程，并结合差分进化算法构建涡轮电推进系统优化模型，形成了涡轮电推进系统控制规律优化设计方法，应用此方法计算了推进系统节流过程控制规律和性能参数。计算结果表明：本模型设计点性能计算结果与国外发动机性能计算软件计算结果最大偏差仅为0.22%，验证了建模方法的有效性；当涵道风扇推力改变时，可能导致涡扇发动机出现超温、超转和喘振等问题，通过联合调节尾喷管喉部面积和涵道引射器面积，可以有效改善这些问题；设计出的节流过程控制规律可以保证不超温、不超转，具有足够的喘振裕度，且在节流过程中还能进一步降低耗油率；该控制规律还具有连续、单调的特点，利于工程实现。

Abstract:

A performance simulation model was established to study the working characteristics and control schedule design method of the turboelectric propulsion system. The calculation model of the ducted fan was established based on the component method. The generator and motor performance calculation models were selected based on the motor efficiency map. The electric module calculation model was established based on the object-oriented modelling method. The electric module model was added to the turbofan component-level model， and the co-working equations of the turboelectric propulsion system， namely its performance simulation model were constructed. The reverse method was used to study the working characteristics when the ducted fan thrust is adjusted under the control schedules of different geometric parameters. By adding the thrust balance equation to the performance simulation model and combining the differential evolution algorithm to construct the optimization model of the turboelectric propulsion system， the optimal design method of the control schedule of the turboelectric propulsion system was formed， and the control schedule and performance of the throttle rating of the propulsion system were calculated. The results show that the maximum deviation between the design point performance calculation results of the simulation model and foreign engine calculation software is only 0.22%， which verifies the effectiveness of the modelling method. The ducted fan thrust changes may cause problems such as over-temperature， over-rotation， and surge of the turbofan engine. By jointly adjusting the area of nozzle throat and bypass injector， these problems can be effectively improved. The designed throttle rating control schedule can ensure that the engine is not over-temperature， over-rotation， and has sufficient surge margin， and the specific fuel consumption can be further reduced during the throttle rating. The control schedule also has the characteristics of continuous and monotonous， which is conducive to engineering realization.