NBI高压电源数字控制PWM-PSM模块研究.doc

NBI高压电源数字控制PWM-PSM模块的研究 陈滋健 周君 摘要: 为了在不降低系统动态性能的情况下提高托卡马克装置NBI加速极高压电源的输出精度，介绍了一种基于数字控制PWM-PSM模块。在分析了电源模块的运行条件之后，重点讨论了变换器拓扑结构、电路参数和数字控制策略。随后对电源系统进行了仿真分析，同时在EAST装置中进行了运行验证。运行结果表明该电源模块能够很好地解决NBI高压电源系统动、稳态性能之间的矛盾，满足EAST装置的运行要求。 关键词: 数字控制；DSP；高压；NBI；PWM电源；光纤 中图分类号： Research on Digital Control PWM-PSM Module for NBI High Voltage Power Supply Chen Zi-jian JIANG Li ZHOU Jun QIAN Lixiu (1. ECU Electronics CO.LTD.of CETC 38, Hefei 230088, China 2. Chinese Academy of Sciences Institute of Plasma Physics, Hefei 230031, China) Abstract: Discussions focus on the design considerations of Digital Control PWM-PSM Module, which is used to improve output voltage precision of the high voltage power supply for the acceleration grids of the neutral beam injectors (NBI) of TOKAMAK under the condition without reducing system dynamic performance. Firstly operating conditions are analyzed, then topological structure, circuit parameter and the digital control method are discussed, on the basis of that the whole power system is simulated, The given PWM-PSM Modules are used to operate in the high voltage power system of the neutral beam injectors of the EAST. The experiment result show that the PWM-PSM module not only can solve conflicts between steady performance and dynamic performance of the high voltage power system, but also be able to meet the requirements of the EAST, which is an advanced full super-conducting TOKAMAK device. Keywords: Digital Control；DSP；High-voltage；NBI；PWM-PSM converter; Fiber-optic; 引言 托卡马克（TOKAMAK）作为磁约束核聚变世界性研究装置，需要通过辅助加热手段将等离子体温度提高到能够产生核聚变反应。中性束注入（Neutral Beam Inject---NBI）[1]，该方案的不足之处是电压调节离散化，使系统输出精度受到限制。可以通过脉冲相移频率合成的PSM控制算法满足输出电压的连续可调，但这种系统必须在输出端增加低通滤波器[2]，滤除等效调制频率。配置输出滤波器无疑使高压电源系统的上升时间和关断时间大大增加，尤其不能满足负载打火时快速切除电源的要求。本文提出的基于数字控制PWM-PSM电源模块叠加在100kV高压电源上运行，和其它PSM电源模块同样具有快速保护和关断功能，同时具有良好的电压调整性能。 系统运行条件分析 基于PSM 技术的高压电源系统及输出如图1 所示，该高压电源系统由多组低压直流电源串联而成。通过电源模块的串联代替了IGBT 模块直接串联，从而能够避免IGBT 模块在直接串联工作模式下因模块提前关断或延后开通而承受高压损坏的缺点。由图1-(a)可以看出，一个最简单的系统由n个PSM电源模块和1个P