摘要
针对已有特高压试验电源拓扑结构的不足,提出一种级联多电平的调频式谐振特高压试验电源拓扑结构及其控制方法。出于减少输出电压总畸变率的考虑,将基于载波移相调制的背靠背级联多电平变流器代替传统单级AC/AC变换器构成大功率调频调压信号源。首先研究整流部分的数学模型及其双闭环控制策略,并引入了电容电压平衡策略,然后研究逆变升压部分的数学模型并提出多环控制策略,最后对优化拓扑的控制方法进行稳定性分析。以级联5电平变流器为例,在PSIM(电力电子仿真)平台上对优化的试验电源进行系统仿真,输入为10kV等级的高压交流电,仿真结果说明该方法成功降低了大功率调频调压信号源的输出电压总畸变率,并减少了变压器的变比,降低变压器的体积和重量,使系统效率提高。
In view of demerits of existing power supply topological structure for UHV tests,we proposed a topological structure of power supply for cascaded multi-level FM resonance extra-high voltage tests and its control method.In order to reduce the total distortion rate of output voltage,the traditional single-level AC/AC converter was replaced by the carrier phase shifting-based back-to-back cascaded multi-level converter to constitute the high-power frequency and pressure-modulation signal source.Firstly,we studied the mathematical model of rectification system and its double-closed-loop control strategy,and introduced a balance strategy for the capacitor voltage.Then,we studied the mathematical model of boosting part of inverter,proposed the multi-loop control strategy,and performed the stability analysis on the improved topological structure and its control method.Taking a cascaded five-level converter as an example,we conducted system simulation on the improved test power supply on the PSIM platform taking 10 kV high-pressure AC as input voltage.The simulation results show that the method can successfully be used to lower the total distortion rate of output voltage of high-power frequency-pressure-modulation signal source,and the transformation ratio,volume and weight of transformer can be reduced,thereby improving the system efficiency.
作者
荆佳琦
李欣然
方璐
JING Jiaqi;LI Xinran;FANG Lu(College of Electrical and Information Engineering,Hunan University,Changsha410082,China;Modern Engineering Training Center,Hunan University,Changsha410082,China)
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2019年第9期2895-2903,共9页
High Voltage Engineering
基金
国家自然科学基金(51507057)
湖南省自然科学基金(2018JJ3056)~~
关键词
特高压交流试验电源
背靠背级联多电平
多环控制策略
拓扑结构
电压畸变率
UHV AC test power supply
back to back cascaded multilevel
the multi-loop control strategy
topological structure
voltage aberration rate
