航空发动机两种加速控制计划的融合控制方法研究

Fusion Control of Two Kinds of Control Schedules in Aeroengine Acceleration Process

关键词:  燃油流量  控制计划  航空发动机  加速过程  喘振  融合控制

Key words:  Fuel flow  Control schedules  Aeroengine  Accelaration process  Surge  Fusion control

摘要:

转速导数（N-dot）和换算燃油流量加速控制计划是航空发动机加速过程安全、快速的重要保障，但各自分别易受到功率提取、性能衰退和传感器、燃油计量装置误差的影响，导致失速喘振或加速性的下降。为了提高所控制加速过程的鲁棒性，一种基于这两种控制计划的融合控制方法被提出，该方法根据两者所获燃油流量的偏差大小对N-dot限控目标值进行修正，进而获得实际的加速燃油流量。以双转子加力涡扇发动机为对象的仿真验证表明，该控制方法可以适应全包线加速控制的需要；相比其余两种控制计划在受功率提取、误差影响下保持正常工作的范围更广；相同工作条件下，该方法比N-dot控制计划更不易发生喘振，比换算燃油流量控制计划的加速时间更短。

Abstract:

The rotor acceleration （N-dot） and the corrected fuel flow control schedules are guarantees for the safety and quickness of aeroengine acceleration. However， they are vulnerable to a surge or longer time due to power extraction， performance degradation and the errors of sensors or fuel metering devices. In order to improve the robustness of the controlled acceleration process， a fusion control method based on the two control schedules is proposed. According to the deviation of fuel flow obtained by the two control schedules， the control objectives of the N-dot control schedule are adjusted to obtain the final fuel flow of accelerating process. The simulation results based on a two-spool turbofan engine show that the fusion control method can meet the needs of full envelope acceleration control， and it can maintain a wider range of complete acceleration process under the influence of power extraction and errors. Besides， under the same working conditions， the method is less possible to surge than the N-dot control schedule， and has less acceleration time than the corrected fuel flow control schedule.