A new guidance law, called biased retro proportional navigation(BRPN), is proposed. The guidance law is designed to intercept high-speed targets with angular constraint, which can be used for ballistic target intercep...A new guidance law, called biased retro proportional navigation(BRPN), is proposed. The guidance law is designed to intercept high-speed targets with angular constraint, which can be used for ballistic target interception. BRPN guidance law is defined, and the exact time-varying bias for a required impact angle is derived. Furthermore, the simulation results(trajectory, variation of navigation ratio, capture region, etc) are compared with those of biased proportional navigation(BPN), proportional navigation and retro-proportional navigation. The results show that,at the cost of a higher intercept time, BRPN demands lower terminal lateral acceleration and has larger capture region compared to BPN.展开更多
This paper proposes a delay-dependent guaranteed cost control scheme for engine idle speed control (ISC) with induction-to-torque delay and external load disturbance. An augmented linearization model of engine at idle...This paper proposes a delay-dependent guaranteed cost control scheme for engine idle speed control (ISC) with induction-to-torque delay and external load disturbance. An augmented linearization model of engine at idle speed operating mode was developed based on physical principle and experiment data. To provide a compromise between disturbance rejection and other performance requirements of ISC, a multi-objective cost function upper bound was given, which can help us to take into account the fuel economy and disturbance rejection performance together in ISC. Poles constraint was added to the closed-loop system to guarantee convergence rates of state. The whole optimization solution to ISC can be solved under the framework of LMI. A commercial engine model was utilized to assess the performance of the controller. Simulation results on this model show us that designed controller can achieve desired performance.展开更多
风电机组一般通过综合惯量控制提供辅助调频,然而其调频效果受控制参数影响较大。文中综合考虑风电机组自身可调能力与系统频率响应指标,对风电调频参数整定进行研究。首先,建立计及风电和火电参与调频的系统频率响应(system frequency ...风电机组一般通过综合惯量控制提供辅助调频,然而其调频效果受控制参数影响较大。文中综合考虑风电机组自身可调能力与系统频率响应指标,对风电调频参数整定进行研究。首先,建立计及风电和火电参与调频的系统频率响应(system frequency response,SFR)模型,并推导频率响应指标的解析式。其次,对风电机组的转子运动方程进行线性化并建立转速模型,在不同风速工况下验证其准确性。然后,以提升系统频率最低点为目标,同时考虑风电机组转速下限和系统频率安全约束,整定其控制参数。最后,仿真结果验证所提风电调频控制参数整定方法在不同风电渗透率以及功率扰动下,均能够在确保系统频率安全的前提下充分利用风电机组的转子动能。展开更多
现有全脉冲结构波形与处理方法,如相位编码波形匹配处理存在多普勒容忍度差的固有缺陷,线性调频(linear frequency modulation,LFM)波形加窗处理降低了距离分辨率和信噪比(signal-to-noise ratio,SNR)增益,难以适应高速多目标探测的任...现有全脉冲结构波形与处理方法,如相位编码波形匹配处理存在多普勒容忍度差的固有缺陷,线性调频(linear frequency modulation,LFM)波形加窗处理降低了距离分辨率和信噪比(signal-to-noise ratio,SNR)增益,难以适应高速多目标探测的任务需求。为此,本文提出了一种面向高速目标探测的多子脉冲结构波形设计与处理方法。首先,构建具有多子脉冲结构波形的回波模型,利用分段子脉冲压缩处理和子脉冲间相参处理方法,导出多子脉冲结构波形的距离-多普勒响应函数;然后,根据感兴趣的目标距离速度区间,建立恒模约束下以最小化加权积分距离-多普勒旁瓣电平为目标函数的多子脉冲结构波形优化设计问题;最后,引入坐标下降(coordinate descent,CD)优化框架,将高维非凸约束优化问题的求解转变为多个一维优化问题的迭代求解,且推导出这些低维问题的闭式解。仿真表明,所设计的多子脉冲结构波形具有较好的多普勒容忍度和较低的局部距离-多普勒旁瓣电平,且在高速多目标认知探测场景下,相比于LFM波形、模糊函数优化波形和LFM-noise波形具有更好的高速目标探测能力。展开更多
文摘A new guidance law, called biased retro proportional navigation(BRPN), is proposed. The guidance law is designed to intercept high-speed targets with angular constraint, which can be used for ballistic target interception. BRPN guidance law is defined, and the exact time-varying bias for a required impact angle is derived. Furthermore, the simulation results(trajectory, variation of navigation ratio, capture region, etc) are compared with those of biased proportional navigation(BPN), proportional navigation and retro-proportional navigation. The results show that,at the cost of a higher intercept time, BRPN demands lower terminal lateral acceleration and has larger capture region compared to BPN.
文摘This paper proposes a delay-dependent guaranteed cost control scheme for engine idle speed control (ISC) with induction-to-torque delay and external load disturbance. An augmented linearization model of engine at idle speed operating mode was developed based on physical principle and experiment data. To provide a compromise between disturbance rejection and other performance requirements of ISC, a multi-objective cost function upper bound was given, which can help us to take into account the fuel economy and disturbance rejection performance together in ISC. Poles constraint was added to the closed-loop system to guarantee convergence rates of state. The whole optimization solution to ISC can be solved under the framework of LMI. A commercial engine model was utilized to assess the performance of the controller. Simulation results on this model show us that designed controller can achieve desired performance.
文摘风电机组一般通过综合惯量控制提供辅助调频,然而其调频效果受控制参数影响较大。文中综合考虑风电机组自身可调能力与系统频率响应指标,对风电调频参数整定进行研究。首先,建立计及风电和火电参与调频的系统频率响应(system frequency response,SFR)模型,并推导频率响应指标的解析式。其次,对风电机组的转子运动方程进行线性化并建立转速模型,在不同风速工况下验证其准确性。然后,以提升系统频率最低点为目标,同时考虑风电机组转速下限和系统频率安全约束,整定其控制参数。最后,仿真结果验证所提风电调频控制参数整定方法在不同风电渗透率以及功率扰动下,均能够在确保系统频率安全的前提下充分利用风电机组的转子动能。
文摘现有全脉冲结构波形与处理方法,如相位编码波形匹配处理存在多普勒容忍度差的固有缺陷,线性调频(linear frequency modulation,LFM)波形加窗处理降低了距离分辨率和信噪比(signal-to-noise ratio,SNR)增益,难以适应高速多目标探测的任务需求。为此,本文提出了一种面向高速目标探测的多子脉冲结构波形设计与处理方法。首先,构建具有多子脉冲结构波形的回波模型,利用分段子脉冲压缩处理和子脉冲间相参处理方法,导出多子脉冲结构波形的距离-多普勒响应函数;然后,根据感兴趣的目标距离速度区间,建立恒模约束下以最小化加权积分距离-多普勒旁瓣电平为目标函数的多子脉冲结构波形优化设计问题;最后,引入坐标下降(coordinate descent,CD)优化框架,将高维非凸约束优化问题的求解转变为多个一维优化问题的迭代求解,且推导出这些低维问题的闭式解。仿真表明,所设计的多子脉冲结构波形具有较好的多普勒容忍度和较低的局部距离-多普勒旁瓣电平,且在高速多目标认知探测场景下,相比于LFM波形、模糊函数优化波形和LFM-noise波形具有更好的高速目标探测能力。
