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| 摘要: |
| 提出了一种基于某改进锁相环的电压凹陷特征量检测方法,可较简单地实现电压凹陷3大特征量(起止时刻、电压幅值、相位跳变)的有效检测。该锁相环为一闭环的相位反馈控制系统,能实时跟踪输入的基波瞬时相位和瞬时幅值。然后由瞬时幅值可检测出电压的幅值下跌以及对应的起始时刻、结束时刻,而根据瞬时相位则可得到相位跳变,从而实现起止时刻、下降幅值、相位跳变等3大电压凹陷特征量的检测。该法结果直观、实时性较好,且内部完成相位自适应跟踪,不需要另外的系统频率测量,实现简单。仿真结果证明了方法的有效性。 |
| 关键词: 电压凹陷,改进锁相环,检测,特征量 |
| DOI： |
| 分类号:TM761 |
| 基金项目:浙江省教育厅科研项目(20060499)~~ |
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| Voltage sag detection based on improved PLL |
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L(U) Ganyun WANG Xiaodong CHENG Haozhong
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| Abstract: |
| A voltage sag detection based on improved PLL(Phase-Locked-Loop) is proposed,which simply detects the three characteristic variables of voltage sags:magnitude,duration and phase jump.The PLL is a closed-loop phase-feedback control system and it follows the instantaneous phase and instantaneous amplitude of input elementary wave,from which the magnitude and duration of voltage sags can be detected from them,as well as the phase jump.This method is direct and simple,with better real time performance and no additional system frequency needed.Simulation results show its effectiveness. |
| Key words: voltage sag,improved PLL,detection,characteristics |
