摘要
针对单相电压型三电平中点钳位(NPC)整流器,首先分析其工作原理,建立其基于开关函数的数学模型。针对单相三电平整流器直流侧两电容电压调节不平衡问题,探讨了一种基于空间电压矢量调制(SVPWM)控制方法和电压前馈的中点电位控制方法,并在Matlab环境下进行了计算机仿真。仿真结果表明,在机车运行的两种典型工况即牵引和再生制动下,SVPWM调制使得牵引变压器一次侧功率因数接近于1,在电网侧可获得近似正弦的电流波形,而且该调制方法易于离散数字化实现。该电压平衡方法能够有效地平衡直流侧电容电压。
The operating principle of single phase three-level neutral-point-clamped （NPC） voltage source rectifier is analyzed firstly, and its mathematical model is founded with switching functions. According to the problem of DC-link voltage unbalance for single three-level rectifier, space vector modulation PWM method （SVPWM） and feedback neutral point potential voltage control are discussed, and the computer simulation in Matlab is carried. The simulation results show that under the two typical modes of the locomotives, traction and regenerative modes, the power factor on the line side is nearly unity by the SVPWM strategy, and the waveform of the current on the line side is nearly sinusoidal. The method is effective in discrete implementation. The capacitors voltage of the DC-link is balanced by the voltage balancing method.
出处
《电工技术学报》
EI
CSCD
北大核心
2007年第7期69-73,共5页
Transactions of China Electrotechnical Society
基金
铁道部重点项目(20060802)资助项目
