Method and device for detecting arcing in electrical installation for DC power
AssigneeSchneider Electric Industries SAS
InventorMounir Djeddi
Life of this patent
Estimating the term…
Abstract
A method for detecting electrical arcs for electrical installations with DC current source, implemented by a detection device including a calculation processor, disposed between the DC current source and a load. A digitized temporal signal is obtained on the basis of the electric current provided by the DC current source. A digitized temporal sub-signal is extracted. A bandpass filtering is applied to the digitized temporal sub-signal. The method also includes calculating a statistical value of order four of the filtered digitized temporal sub-signal, and comparing the calculated statistical value of order four with a first statistical threshold.
Claims13
A method for detecting electrical arcs for photovoltaic installations with a DC current source, implemented by a detection device comprising a calculation processor, disposed between the DC current source and a load, the method comprising:
- obtaining a digitized temporal signal based on an electric current provided by the DC current source,
- for a plurality of successive time windows of predetermined temporal duration:
- extracting a digitized temporal sub-signal of said digitized temporal signal corresponding to a current time window,
- applying a bandpass filtering to said digitized temporal sub-signal,
- calculating a statistical value of order four of the filtered digitized temporal sub-signal,
- comparing the calculated statistical value of order four with a first statistical threshold and/or with a second statistical threshold, and in the case where the statistical value of order four is less than the first statistical threshold, or in the case where the statistical value of order four is greater than the second statistical threshold, storing a positive detection indication in respect of the current time window,
- detecting presence of electrical arc when a number of stored indications of positive detection exceeds a predetermined detection threshold,
- triggering a safety device to interrupt supply of the electric current provided by the DC current source in response to detection of the presence of the electrical arc, and
- calculating a coefficient of variation dependent on the mean and the statistical value of order two of the digitized temporal sub-signal corresponding to the current time window before bandpass filtering, and updating said positive detection indication when said coefficient of variation exceeds a predetermined variation threshold.
A device for detecting electrical arcs for photovoltaic installations with DC current source, comprising:
- a calculation processor, disposed between the DC current source and a load, the calculation processor being configured to
- obtain a digitized temporal signal based on an electric current provided by the DC current source,
- for application to a plurality of successive time windows of predetermined temporal duration,
- extract a digitized temporal sub-signal of said digitized temporal signal corresponding to a current time window,
- bandpass filter said digitized temporal sub-signal,
- calculate a statistical value of order four of the filtered digitized temporal sub-signal,
- perform a comparison of the calculated statistical value of order four with a first statistical threshold and/or with a second statistical threshold, and where the statistical value of order four is less than the first statistical threshold, or where the statistical value of order four is greater than the second statistical threshold, store a positive detection indication in respect of the current time window,
- detect a presence of an electrical arc when a number of stored indications of positive detection exceeds a predetermined detection threshold, and
- trigger a safety device to interrupt supply of the electric current provided by the DC current source in response to detection of the presence of the electrical arc,
- wherein the calculation processor is further configured to calculate a coefficient of variation dependent on a mean and the statistical value of order two of the digitized temporal sub-signal corresponding to the current time window before bandpass filtering.
Dependencies are inferred from the claim text.