自由电子激光脉冲调制器高稳定性若干关键技术研究

XFEL (X-ray Free-Electron Laser) facility demands higher energy stability for electron beam. Normally XFEL needs that stabilities of modulator and klystron should be up to 0.01% or more higher. Stability of microwave power source directly depends on stability of pulsed modulator, because klystron works in saturation condition commonly. Presently, stability of high-power pulse modulator of LINAC(Linear Accelerator) is on the level of 0.1% to 0.05% usually. Therefor, stability of modulator must be enhanced in order to satisfy high stability requirements of LINAC in XFEL facility.The research contents of the project are such as, analyzing factors bringing influence to short-term and long-term stability of modulator, and consequently seeking and adopting appropriate control scheme, introducing digital high precision feedback technology and ultimately improving short-term and long-term stability in order to meet high stability requirements of XFEL. The concrete goals of the project are such as, no disturbance sampling of charging voltage and pulse voltage, high precision data acquisition and data analysis, research on feedback control methods and implementation of feedback controller module. Ultimately, stability of modulator is prior to the 0.01% level.

X射线自由电子激光(XFEL)装置对电子束能量稳定有很高的要求。通常XFEL对调制器、速调管的微波功率的稳定度要求达到0.01%或更高。由于速调管工作在饱和状态，因此调制器的功率稳定性直接决定微波功率源的稳定。直线加速器高功率脉冲调制器的稳定性水平通常在0.1%-0.05%的水平。因此必须提高调制器的稳定性以满足XFEL对直线加速器的高稳定性的要求。该项目的研究内容是，理论上分析调制器稳定性影响因素，选择合适的控制方案；使得调制器在现有条件下，加入数字化高精度反馈控制技术后，其短期、长期稳定性能满足XFEL对调制器的要求。该项目研究的具体目标是，充电电压以及脉冲电压的无干扰取样、取样信号的高精度采集和数据分析处理、反馈控制算法研究以及反馈控制器的模块功能实现等。最终调制器稳定性能优于0.01%。

X射线自由电子激光(XFEL)装置对电子束能量稳定有很高的要求。通常XFEL对调制器、速.调管的微波功率的稳定度要求达到0.01%或更高。本项目在系统理论分析的基础上，着重研究研制高稳定性的充电电源。根据充电电源稳定性在调制器中工作的机理，充电电源采用两套基于数字化控制的LC谐振参数应对快速充电及精细充电模式。此外，还设计了高精度数据采集系统来构成闭环控制，实现了稳定性调制器系统的初步测试。从目前的理论分析和进展来看，本项目能够达到预期的目标，为高稳定性调制器的研制及充电电源的研制奠定坚实的基础。