Multi-frequency signal measurement method and system

Abstract

The invention discloses a multi-frequency signal measuring method and system. The method comprises steps of acquiring multiple to-be-measured signals by use of preset sampling frequency; acquiring amplitude information of multiple to-be-measured signals and according to the amplitude information, determining the number of frequency components included in the to-be-measured signals; according to the amplitude information of the to-be-measured signals, judging whether each frequency component in each to-be-tested signal is sampled in the whole period; if there is at least one frequency componentwhich is not sampled in the whole period, carrying out error correction on the to-be-measured signal so as to acquire information of each frequency component of the corresponding to-be-measured signal. According to the invention, multi-frequency signals including multiple kinds of frequency components are precisely analyzed; there is no need for a data acquisition system to achieve whole-period sampling on the to-be-measured signals; in the algorithm, erros will not introduced caused by the fact whether the sampling process is a whole-period sampling process or not; and measurement accuracy is improved.

Description

technical field [0001] The invention relates to the technical fields of harmonic signal measurement in the field of electrical engineering, vibration signal monitoring in the field of mechanical engineering, multi-frequency signal measurement of electrical and electronic systems in the field of aerospace, and verification and traceability of multi-frequency signal sources in the field of electrical measurement. Frequency signal measurement method and system. Background technique [0002] With the wide application of power electronic devices and the increase of various nonlinear loads, the problem of harmonic pollution in power systems is becoming more and more serious. In the power grid, there are not only integer harmonics of power frequency, but also non-integer harmonics of power frequency, that is, inter-harmonics. Harmonics / interharmonics will cause noise and vibration of the induction motor, cause voltage flicker, etc., and deteriorate the power quality. In addition ...

AI Technical Summary

Problems solved by technology

However, in practice, due to the unknown period of each frequency component of the measured signal and the limitation of the hardware of the data acquisition system, it is usually difficult to achieve full-period sampling

Under non-full cycle sampling conditions, due to the influence of long-range spectrum leakage, short-range spectrum leakage, and negative frequency spectrum leakage, large errors will occur when using DFT to analyze signals

Images