用于光伏发电系统的LLCL型滤波器混合阻尼控制策略

Hybrid Damping Control Strategy for LLCL Filters of PV Systems

为使光伏系统并网电流谐波满足电力系统的要求,提出采用基于LLCL型滤波器的并网逆变器,并对其进行有源及无源相结合的混合阻尼控制。通过对混合阻尼参数的取值进行合理设计,使无源阻尼与有源阻尼的控制优势得以更好的结合与发挥。在Matlab/Simulink环境下对控制方案进行仿真,结果表明,混合阻尼控制方案下的LLCL型滤波器不但具有衰减开关频率次谐波和节省电网侧电感的优点,还具有较好的滤波能力,可以满足并网电流的谐波含量限制要求。

In order to make the photovoltaic（PV） system meet the standards on grid-connected current harmonics,an LLCL filter-based inverter is developed with a hybrid active and passive damping control strategy.By setting the parameters of the hybrid damping scheme properly,the advantages of passive and active damping controls are combined and made full use.Finally,the presented control scheme is simulated by the program of Matlab/Simulink,which shows that the LLCL filter with a hybrid damping control scheme can not only attenuate the harmonics around the switching frequency and reduce the inductance of the grid side,but also demonstrate its good filtering capability to guarantee the grid-connected current harmonics complied with the related standards.