引用本文: | 沈开奎,李延龙,赵媛,李少华.电网瞬时频率跟踪算法设计[J].电力系统保护与控制,2015,43(5):75-80.[点击复制] |
SHEN Kaikui,LI Yanlong,ZHAO Yuan,LI Shaohua.Design of the grid instantaneous frequency tracking algorithm[J].Power System Protection and Control,2015,43(5):75-80[点击复制] |
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摘要: |
在高压直流输电工程中,采用高精度锁相环跟踪电网相位,并在设定角度产生点火脉冲触发换流阀,瞬时电网频率跟踪速度和精度对锁相环至关重要,传统的频率测量方法无法同时满足速度和精度的要求。提出了一种电网瞬时频率跟踪算法。该算法将三相电压瞬时值进行Clarke变换,经有限冲激相应滤波器(FIR)滤除谐波和负序分量后,计算电网实时相位,采用相差法实现了对电网瞬时频率的跟踪。通过仿真和实验验证,该算法可准确、快速地跟踪各种电力信号的瞬时频率,有效地滤除谐波和噪声,电网瞬时频率的测量精度高达±0.005 Hz。 |
关键词: 瞬时频率测量 Clarke变换 FIR滤波器 频率跟踪算法 锁相环 |
DOI:10.7667/j.issn.1674-3415.2015.05.012 |
投稿时间:2014-05-07修订日期:2014-06-17 |
基金项目: |
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Design of the grid instantaneous frequency tracking algorithm |
SHEN Kaikui,LI Yanlong,ZHAO Yuan,LI Shaohua |
(XJ Electric Co., Ltd., Xuchang 461000, China) |
Abstract: |
In HVDC transmission project, the high-precision phase-locked loop is used to trace the real-time grid phase, when the simulated phase is equal to the trigger angle, the trigger pulses are generated and the converter valves are triggered, so the instantaneous frequency tracing should be fast and accurate, but the traditional frequency measurement algorithms could not meet both the speed and the accuracy requirements simultaneously. This paper designs a new grid instantaneous frequency tracking algorithm. This algorithm transforms the three-phase voltages of grid by Clarke transformation; after filtering the harmonics and negative sequence components by using the FIR, it calculates the grid instantaneous frequency, and tracks grid synchrounous frequency with phase-difference method. According to the simulations and experiments, the algorithm can precisely and quickly trace the grid instantaneous frequency, and the accuracy is up to ±0.005 Hz. |
Key words: instantaneous frequency measurement Clarke transformation FIR filter frequency tracing algorithm PLL |