|
|
A novel phase-locked loop under harmonic grid condition |
ZHANG Lei |
School of Intelligent Engineering, Jiangsu Vocational College of Information Technology, Wuxi, Jiangsu 214153 |
|
|
Abstract Grid synchronization technique is one of the key techniques in the grid-connected operation of distributed power generation systems. In order to solve the problems that there exists second and higher harmonics in the traditional single-phase stationary reference frame phase-locked loop (PLL) and imaginary orthogonal signal is needed for synchronous reference frame PLL which can't totally eliminate grid harmonics at the same time, a new single-phase PLL method without imaginary orthogonal signal generation is put forward. This proposed method embeds a cascade control structure on the basis of the traditional stationary reference frame PLL. The corresponding open-loop system to such structure generates the resonant peak at the grid harmonics which are exported by the phase discriminator so that the corresponding harmonics can be completely eliminated in the closed-loop control and purer frequency, phase and other related information can be extracted by the proposed PLL. Finally, the proposed PLL is tested by the related experiment under different grid conditions. The results how the validity and superiority of this method.
|
Received: 17 November 2020
|
|
|
|
[1] TAKAGI K, FUJITA H.A three-phase grid-connected inverter equipped with a shunt instantaneous reactive power compensator[J]. IEEE Transactions on Industry Applications, 2019, 55(4): 3955-3966. [2] 刘飞, 陶昕, 张祥成, 等. 基于电网消纳能力的新能源发展策略研究[J]. 电气技术, 2019, 20(6): 50-55. [3] 程思举, 杨建华, 肖达强, 等. 基于多指标评价的清洁能源互补优选策略[J]. 电气技术, 2020, 21(1): 25-30. [4] 何宇, 漆汉宏, 罗琦, 等. 基于分数阶滤波器的三相锁相环技术[J]. 电工技术学报, 2019, 34(12): 2572-2583. [5] TEODORESCU R, LISERRE M, RODRÍGUEZ P. Grid converters for photovoltaic and wind power systems[M]. Hoboken: John Wiley & Sons, 2011. [6] 关清心, 张宇, 李民英, 等. 基于微分环节的单相锁相环方法[J]. 中国电机工程学报, 2016, 36(19): 5318-5325. [7] 康成伟, 顾诚博, 李伟杰, 等. 基于SOGI单相锁相环的列车辅助逆变器并联技术[J]. 电工电能新技术, 2019, 38(5): 68-73. [8] 乔和, 张文斌, 于浩, 等. 非理想条件下的电网同步锁相技术[J]. 电力系统及其自动化学报, 2017, 29(7): 98-102. [9] 刘华吾, 孙永恒, 胡海兵, 等. 谐波畸变电网下的单相同步旋转坐标系锁相环[J]. 电力系统自动化, 2016, 40(13): 93-99. [10] 王涛, 诸自强, 年珩. 非理想电网下双馈风力发电系统运行技术综述[J]. 电工技术学报, 2020, 35(3): 453-471. |
|
|
|