基于频率跟踪的定频采样测量算法

Fixed frequency sampling measurement based on frequency tracing

针对传统测量算法的改进,提出一种基于软件的频率跟踪测量算法,应用于固定频率的保护和测控一体化装置。在较低的固定采样频率下根据采样值实时计算出被测量的实际频率,再根据频率偏差用软件算法补偿修正被测量,进而得到准确的测量值。仿真结果表明,该算法可以在较宽的频率范围内,对含有谐波的交流量实现精确测量。该算法应用于实际的数字式保护测控装置,既不影响继电保护动作,又能满足测量精度,取得了良好的效果。

To improve traditional measuring algorithms,a software frequency tracing measurement method is presented for the protection and measuring-control integrated device with fixed frequency. Under lower fixed sampling frequency,the real frequency of the measurement is calculated real-timely according to the sampled values. Then the measured data is modified to accurate values by software according to the frequency deviation. Simulation results show that,the AC variables with harmonics can be measured accurately in a wide frequency range. Applied in digital protections and measuring-control integrated devices,it satisfies the measuring precision,without influencing protective actions,