摘要
介绍了中点钳位型三电平变流器的数学模型,分析了电网谐波条件下变流器谐波电流产生的原理。提出一种新型电网谐波下三电平变流器的谐波电流抑制方案,该方案采用α-β正负序解耦计算电网电压基波前馈项,采用d-q正负序解耦进行电流闭环控制,并引入电网电压谐波经P调节器作为电压前馈项叠加至基波调制波进行谐波电流抑制。Matlab仿真表明,所提控制策略比传统的d-q正负序解耦控制,明显改善了谐波电流含量。
The mathematical model of three - level neutral - point - clamped converter is introduced, and the theory of harmonic current generated by harmonic grid voltage is analyzed. A novel harmonic current suppression strategy is proposed. The strategy use α -β positive and negative sequence decoupling to calculate the fundamental component of grid voltage, use d- q positive and negative sequence decoupling to control current loop, and use harmonic grid voltage through P controller to suppress harmonic current. The feasibility of this strategy is analyzed by Matlab simulation. Compared with the traditional d - q decoupling control, the simulation of the proposed control strategy significantly improves the harmonic current.
出处
《四川电力技术》
2015年第2期26-31,共6页
Sichuan Electric Power Technology
关键词
三电平变流器
谐波电流抑制
正负序解耦
电压前馈
three -level converter
harmonic current suppression
positive and negative sequence decoupling
feed -forward of voltage
