基于SOGI和级联DSC的正负序分量分离及其在不平衡PWM整流器中的应用

Separation of Positive and Negative Sequence Component Based on SOGI and Cascade DSC and Its Application in Unbalanced PWM Rectifier

二阶广义积分器(SOGI)和级联延迟信号消除(DSC)都可用于正负序分量分离,但都有各自的缺点。为了从不平衡电网中提取电网的正序和负序基波分量,提出了消除高次谐波的SOGI和消除特定频率的DSC消谐策略。仿真结果表明,无论是在电网电压失真,还是发生对称故障和不对称故障的情况下,该方法都可以快速、准确地分离电网的正负序基波分量,并且还可用于不平衡脉冲宽度调制整流器的控制。

The second-order generalized integrator（SOGI） and cascade delayed signal cancellation（DSC） are used respectively in the separation of positive and negative component. But they have their own disadvantages. In order to extract grid＇s positive and negative sequence fundamental component from unbalanced power system,the strategy of second-order generalized integrator eliminating higher harmonic and cascade delayed signal cancellation eliminating the specific frequency harmonic is put forward. The simulation results showthat it can separate the positive and negative sequence fundamental components quickly and accurately in the case of grid voltage distortion,symmetrical fault and asymmetric fault,and it can be applied to the control of unbalanced pulse width modulation rectifier.