Reaction control system(RCS) is a powerful and efficient actuator for space vehicles attitude control, which is typically characterized as a pulsed unilateral effector only with two states(off/on). Along with inevitab...Reaction control system(RCS) is a powerful and efficient actuator for space vehicles attitude control, which is typically characterized as a pulsed unilateral effector only with two states(off/on). Along with inevitable internal uncertainties and external disturbances in practice, this inherent nonlinear character always hinders space vehicles autopilot from pursuing precise tracking performance. Compared to most of pre-existing methodologies that passively suppress the uncertainties and disturbances, a design based on predictive functional control(PFC) and generalized extended state observer(GESO) is firstly proposed for three-axis RCS control system to actively reject that with no requirement for additional fuel consumption. To obtain a high fidelity predictive model on which the performance of PFC greatly depends, the nonlinear coupling multiple-input multiple-output(MIMO) flight dynamics model is parameterized as a state-dependent coefficient form. And based on that, a MIMO PFC algorithm in state space domain for a plant of arbitrary orders is deduced in this paper.The internal uncertainties and external disturbances are lumped as a total disturbance, which is estimated and cancelled timely to further enhance the robustness. The continuous control command synthesised by above controller-rejector tandem is finally modulated by pulse width pulse frequency modulator(PWPF) to on-off signals to meet RCS requirement. The robustness and feasibility of the proposed design are validated by a series of performance comparison simulations with some prominent methods in the presence of significant perturbations and disturbances, as well as measurement noise.展开更多
针对RLV(Reusable Launch Vehicle)的再入控制提出了一种基于模糊逻辑的RCS(Reaction Control System).详细分析了RCS控制特性,建立了基于效率系数以及继电特性的RCS模型,提出了一种基于Mamdani模型的模糊逻辑三通道RCS控制器,该控制器...针对RLV(Reusable Launch Vehicle)的再入控制提出了一种基于模糊逻辑的RCS(Reaction Control System).详细分析了RCS控制特性,建立了基于效率系数以及继电特性的RCS模型,提出了一种基于Mamdani模型的模糊逻辑三通道RCS控制器,该控制器利用专家控制经验,根据姿态角及角速率的偏差,产生不同的RCS控制指令输出给三通道对飞行器进行姿态控制.通过六自由度非线性仿真,验证了该控制系统与PID(Proportional-Integral-D ifferential)控制器相比具有更好的跟踪性能,且RCS的控制输出效率也更高.展开更多
为满足反作用控制系统(reaction control system,RCS)姿态控制需求,对高超声速飞行器再入段的姿态控制进行研究。以X-34的RCS系统为对象,建立了RCS的数字模型,设计了RCS姿态控制率与PWPE脉冲调制器,利用非线性描述函数法分析姿态控制系...为满足反作用控制系统(reaction control system,RCS)姿态控制需求,对高超声速飞行器再入段的姿态控制进行研究。以X-34的RCS系统为对象,建立了RCS的数字模型,设计了RCS姿态控制率与PWPE脉冲调制器,利用非线性描述函数法分析姿态控制系统的稳定性,并通过Matlab仿真验证了所设计的RCS姿态控制系统性能。仿真结果表明:该PWPF脉冲调制可以满足RCS姿态控制的需要,同时与传统的PWM脉冲调制相比,可以较大地降低RCS消耗的流量与开启次数,可为高超声速飞行器再入段RCS姿态控制系统设计提供参考。展开更多
通过RCS-992系列稳定控制装置采集保护装置动作信号、断路器合跳闸继电器接点位置,实时判别500kV砚都变电站与肇庆换流站之间的联络线是否满足最后1台断路器保护、同名相故障检测的逻辑条件,如果其中之一的判别逻辑条件满足,则向肇庆换...通过RCS-992系列稳定控制装置采集保护装置动作信号、断路器合跳闸继电器接点位置,实时判别500kV砚都变电站与肇庆换流站之间的联络线是否满足最后1台断路器保护、同名相故障检测的逻辑条件,如果其中之一的判别逻辑条件满足,则向肇庆换流站发出紧急关断顺序(emergency shutdown of frequence,ESOF)命令以闭锁高肇直流输电系统,避免肇庆换流站出现交流过电压情况而导致设备损坏的问题。对RCS-992系列稳定控制装置可靠性要求高的问题,提出了针对性较强的防误措施,有利于装置的安全稳定运行。展开更多
Controlled,guided munitions can reduce dispersion in the shot,while providing the capability of engaging both stationary and maneuvering targets.The Netherlands Organisation for Applied Scientific Research has develop...Controlled,guided munitions can reduce dispersion in the shot,while providing the capability of engaging both stationary and maneuvering targets.The Netherlands Organisation for Applied Scientific Research has developed a fin-less control technology called Stagnation Pressure Reaction Control(SPRC)that takes stagnation pressure air and directs it sideways to control non-spinning projectiles.In a previous study,this technology was demonstrated at Mach 2 wind-tunnel conditions to achieve up to 1.5°controllable angle of incidence for a non-spinning,aerodynamically unstable projectile-like test object.In an operational scenario,the decelerating projectile will experience a decline in control force while the simultaneous forward shift of the center of pressure increases the need for control force.Furthermore,angles of incidence exceeding 1.5°will be experienced under realistic flight conditions,especially against maneuvering targets.This work addresses these challenges and presents an operational feasibility study for a practical application of SPRC in a non-spinning mid-caliber gun-launched projectile,using experiment data on control latency and force of the earlier study.It illustrates the combined effect of the control-and stability dynamics and underlines the potential of an SPRC projectile as a precisionoperation ammunition.This research revealed that SPRC technology can stabilize and control the hypothesized projectile in a direct fire scenario against stationary and maneuvering targets.展开更多
文摘Reaction control system(RCS) is a powerful and efficient actuator for space vehicles attitude control, which is typically characterized as a pulsed unilateral effector only with two states(off/on). Along with inevitable internal uncertainties and external disturbances in practice, this inherent nonlinear character always hinders space vehicles autopilot from pursuing precise tracking performance. Compared to most of pre-existing methodologies that passively suppress the uncertainties and disturbances, a design based on predictive functional control(PFC) and generalized extended state observer(GESO) is firstly proposed for three-axis RCS control system to actively reject that with no requirement for additional fuel consumption. To obtain a high fidelity predictive model on which the performance of PFC greatly depends, the nonlinear coupling multiple-input multiple-output(MIMO) flight dynamics model is parameterized as a state-dependent coefficient form. And based on that, a MIMO PFC algorithm in state space domain for a plant of arbitrary orders is deduced in this paper.The internal uncertainties and external disturbances are lumped as a total disturbance, which is estimated and cancelled timely to further enhance the robustness. The continuous control command synthesised by above controller-rejector tandem is finally modulated by pulse width pulse frequency modulator(PWPF) to on-off signals to meet RCS requirement. The robustness and feasibility of the proposed design are validated by a series of performance comparison simulations with some prominent methods in the presence of significant perturbations and disturbances, as well as measurement noise.
文摘为满足反作用控制系统(reaction control system,RCS)姿态控制需求,对高超声速飞行器再入段的姿态控制进行研究。以X-34的RCS系统为对象,建立了RCS的数字模型,设计了RCS姿态控制率与PWPE脉冲调制器,利用非线性描述函数法分析姿态控制系统的稳定性,并通过Matlab仿真验证了所设计的RCS姿态控制系统性能。仿真结果表明:该PWPF脉冲调制可以满足RCS姿态控制的需要,同时与传统的PWM脉冲调制相比,可以较大地降低RCS消耗的流量与开启次数,可为高超声速飞行器再入段RCS姿态控制系统设计提供参考。
文摘通过RCS-992系列稳定控制装置采集保护装置动作信号、断路器合跳闸继电器接点位置,实时判别500kV砚都变电站与肇庆换流站之间的联络线是否满足最后1台断路器保护、同名相故障检测的逻辑条件,如果其中之一的判别逻辑条件满足,则向肇庆换流站发出紧急关断顺序(emergency shutdown of frequence,ESOF)命令以闭锁高肇直流输电系统,避免肇庆换流站出现交流过电压情况而导致设备损坏的问题。对RCS-992系列稳定控制装置可靠性要求高的问题,提出了针对性较强的防误措施,有利于装置的安全稳定运行。
文摘Controlled,guided munitions can reduce dispersion in the shot,while providing the capability of engaging both stationary and maneuvering targets.The Netherlands Organisation for Applied Scientific Research has developed a fin-less control technology called Stagnation Pressure Reaction Control(SPRC)that takes stagnation pressure air and directs it sideways to control non-spinning projectiles.In a previous study,this technology was demonstrated at Mach 2 wind-tunnel conditions to achieve up to 1.5°controllable angle of incidence for a non-spinning,aerodynamically unstable projectile-like test object.In an operational scenario,the decelerating projectile will experience a decline in control force while the simultaneous forward shift of the center of pressure increases the need for control force.Furthermore,angles of incidence exceeding 1.5°will be experienced under realistic flight conditions,especially against maneuvering targets.This work addresses these challenges and presents an operational feasibility study for a practical application of SPRC in a non-spinning mid-caliber gun-launched projectile,using experiment data on control latency and force of the earlier study.It illustrates the combined effect of the control-and stability dynamics and underlines the potential of an SPRC projectile as a precisionoperation ammunition.This research revealed that SPRC technology can stabilize and control the hypothesized projectile in a direct fire scenario against stationary and maneuvering targets.