Test and study on sensitivity of electronic circuit in low-voltage release to voltage sags

This study focuses on sensitivity of electronic circuit in low-voltage release to voltage sags based on a large-scale test results. Although studies about ride-through capability of some electronic devices during voltage sags have been carried out, there is few research available on sensitivity of electronic circuit in low-voltage release to voltage sags. Operation principle and working states of electromagnetic structure are discussed. Subsequently, a detailed test scheme is proposed based on latest standards and several kinds of 220V low-voltage releases have been tested. Test results indicate that output waveform of electronic circuit under voltage sags can be classified into two types, which shows a clear correspondence with working state of electromagnetic structure and tripping condition of low-voltage release. Finally, six working modes are presented to analyse the relationship between output waveform of electronic circuit and the magnitude and duration of voltage sags in details.