Abstract: At least one embodiment of the present invention provides a method for detecting voltage disturbance. In at least one embodiment the method includes storing the digitized point values of a voltage reference waveform; detecting actual voltage values, and converting the actual voltage values by digitization into point values of the actual voltage which are in one-to-one correspondence with the point values of the reference waveform; comparing the point values of the actual voltage with the corresponding point values of the reference waveform; judging that a voltage disturbance occurs if, for N successive points, the differences between the point values of the actual voltage and the corresponding point values of the reference waveform are all greater than a predetermined disturbance threshold, wherein N is an integer greater than 0. A technical solution of the present invention improves the response speed of the detection, and shortens the response time.

Abstract: A power monitoring device is disclosed. In at least one embodiment, the power monitoring device includes a power parameter measurement unit for calculating the measurement results of basic power parameters according to acquired digital signals of a voltage and/or a current; and a power quality analysis unit including a field programmable gate array, for obtaining power quality analysis results by executing a wavelet transform algorithm, a fast Fourier transform algorithm, an artificial neural net algorithm or a fuzzy logic algorithm in a parallel mode according to the acquired digital signals of voltage and/or current to perform analysis of stationary and transient power quality disturbances. Since the power monitoring device of at least one embodiment of the present invention employs a field programmable gate array, it can perform power quality analysis, power parameter measurements and other peripheral functions with relatively good performance.

Abstract: At least one embodiment of the present invention provides a method for detecting voltage disturbance. In at least one embodiment the method includes storing the digitized point values of a voltage reference waveform; detecting actual voltage values, and converting the actual voltage values by digitization into point values of the actual voltage which are in one-to-one correspondence with the point values of the reference waveform; comparing the point values of the actual voltage with the corresponding point values of the reference waveform; judging that a voltage disturbance occurs if, for N successive points, the differences between the point values of the actual voltage and the corresponding point values of the reference waveform are all greater than a predetermined disturbance threshold, wherein N is an integer greater than 0. A technical solution of at least one embodiment of the present invention improves the response speed of the detection, and shortens the response time.