摘要医用直线加速器是用于肿瘤放射治疗的重要设备，其输出剂量的稳定性是影响肿瘤治疗效果的重要因素。影响输出剂量稳定性的主要因素包括自动频率控制（Automatic Frequency Control，AFC）系统、加速管性能、磁控管性能等。本文主要从AFC系统的原理及调试方面阐述控制磁控管的微波输出频率，使之和加速管的谐振频率保持一致，从而保持直线加速器输出剂量率稳定性的方法。
Abstract：Medical linear accelerator is one of the importment devices used in tumor radiotherapy, and its output dose stability can affect therapeutic effect significantly. The factors including the automatic frequency control system, the performance of accelerating tube and the performance of magnetron can affect the output dose stability. This paper introduces the principle and debugging of AFC system to find the methods about controlling the microwave output frequency of magnetron to make it keep pace with the resonant frequency of accelerating tube so that the output dose stability of linear accelerator can be maintained.
李殿强，杜嘉丽，刘亚平. BJ-6B400型直线加速器AFC系统原理及调试[J]. 中国医疗设备, 2013, 28(10): 165-167.
LI Dian-qiang, DU Jia-li, LIU Ya-ping. The Principle and Debugging of AFC System of BJ-6B400 Linear Accelerator. China Medical Devices, 2013, 28(10): 165-167.
