为了满足微波放大器副特性测试需要, 研制了高精度电源调制器系统。采用阶梯调制与循环控制相结合的方式, 实现了高稳定度输出控制。对调制器的拓扑结构和控制策略进行了分析, 并介绍了脉冲步进调制器(PSM)模块和多绕组变压器等关键部件的设计方法。试验结果表明: 采用PSM技术的电源调制器电源系统输出指标满足测试要求, 能够稳定可靠工作并具备快速保护功能。

To measure high frequency auxiliary character of klystron, a high stability CW modulator is designed. The modulator’s output voltage is 45 kV and output current is 9 A. 64 PSM(pulse step modulation) modules being connected in series have capability of both pulse and CW operation mode, and their output voltage can be adjusted from 500 μs pulse width to DC. Combined with step-modulation and cycle control strategy, high stability output is realized. Design of PSM module and multi-secondary transformer is given. Results of experiment prove that the modulator’s output voltage stability is less than 0.1% and could turn off in less than 5 μs when arc takes place.