摘要
锁相环作为一种可以有效地检测出电网电压相角的方法,在分布式发电系统中得到了广泛应用。对于畸变的三相电网而言,采样传统的锁相方法无法同时达到较好的动态性能与稳态性能。而采用信号延迟对消算子可以有效地消除电网电压不平衡和低次谐波对锁相的影响,提高系统的带宽。本文在优化选择延迟对消算子的基础上,提出了一种二型三阶的调节器来抑制电网电压高次谐波对锁相的影响,同时也提出了一种根据相位裕度和谐波抑制要求直接计算出调节器参数的方法,从而避免了反复试凑。最后通过实验证明了理论分析的正确性和闭环设计方法的有效性。
During the grid synchronization of the distributed generation units, phase-locked loop(PLL) is well accepted as an efficient approach to detect grid phase angle. For the conventional PLL scheme, there's a compromise between tracking accuracy and dynamic performance if the grid voltage is distorted. However, the delayed signal cancellation(DSC) operators can eliminate unbalance component and low order harmonics effectively, and thus the bandwidth of the system can be improved. Based on the DSC operators, this paper proposes a two-type three-order controller which can significantly improve the ability of the PLL to reject high order harmonics, and also proposed a method which can directly calculate the control parameters based on phase margin and harmonic rejection requirements without the try and error procedure. A phase-locked loop system prototype is built and tested in the lab. The experimental results are given to verify the validity of theoretical analysis presented above.
出处
《电工技术学报》
EI
CSCD
北大核心
2014年第8期255-264,共10页
Transactions of China Electrotechnical Society
关键词
三相锁相环
延迟对消算子
二型三阶调节器
闭环参数设计
Three-phase PLL,delayed signal cancellation operator,two-type three-order controller,control loop design
