Pulse waveform amplitude variation analysis method and device

Abstract

The embodiment of the invention provides a pulse waveform amplitude variation analysis method and device. The method comprises the steps that pulse waveform and the number of the jump edges of the pulse waveform are acquired; the size of a first window is determined so that the number of the jump edges searched in the pulse waveform according to the first window is enabled to be equal to the number of the jump edges of the pulse waveform inputted by the user; the first window is slid on the pulse waveform, and the position of the jump edges in the pulse waveform and the start point coordinates and the end point coordinates of the jump edges are determined; and statistical analysis is performed on the signal amplitude variation of the pulse waveform within the unit period of time according to the start point coordinates and the end point coordinates of the jump edges in the pulse waveform. According to the pulse waveform amplitude variation analysis method and device, the accuracy of pulse waveform analysis can be enhanced.

Description

technical field [0001] Embodiments of the present invention relate to the technical field of signal analysis, and in particular, to a method and device for analyzing amplitude changes of pulse waveforms. Background technique [0002] The pulse width modulation (PWM) driving pulse generated by the wind turbine converter is generally a high-frequency differential mode voltage. When it is transmitted from the bottom of the tower to the motor side through a long-distance cable, there will be leakage inductance and coupling Capacitors, high-frequency differential mode voltage will cause voltage reflection on the motor side, causing overvoltage on the motor side, which will easily cause huge damage to the motor. Therefore, filters are usually used in the design to improve the PWM high frequency differential mode voltage characteristics, so as to effectively protect the generator. [0003] When the PWM pulse voltage jumps, the voltage change per unit time is defined as du / dt, and ...

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Problems solved by technology

[0004] At present, there is no automatic method to evaluate the du / dt of the filter, which makes the process of obtaining the starting point and end point of the transition edge and calculating its du / dt only manually, so for a section with 20-30 For the PWM voltage waveform of a transition edge, the experimenter usually randomly extracts 2-3 transition edges from the entire waveform manually to calculate its du / dt, and calculate the average as the du / dt characteristic of the entire waveform

However, in fact, there is a large error in this du / dt evaluation method, because the du / dt difference of each transition edge in a voltage waveform is relatively large, and the du / dt characteristics of the entire waveform obviously cannot be determined by 2-3 evaluation, thus leading to the problem of lower accuracy

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