PROTECTION AND DIAGNOSTIC METHOD FOR IN-SERIES THYRISTORS AND DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2014 - IPC H02H7/10 H02H7/12 H02M1/34 

FIELD: electricity.

SUBSTANCE: protection and diagnostic method for in-series thyristors lies in stoppage of control pulses delivery as a protective measure, performance of control over state of the thyristors against reverse voltage and operating temperature of valve coolers. In the method correct operation of communication lines is controlled by pulse-phase control system against feedback response, distribution of reverse voltage is measured in each operating cycle of the valve groups. When maximum allowable temperature of the valves is exceeded or rated value of reverse voltage distribution is decreased or in case of lost connection with the pulse-phase control system protective measures are taken by removal of pulses from all thyristor groups and cutoff of the converter from the network or by removal of control pulses only. By means of the analysis for reverse voltage distribution and operating temperature of thyristors an emergency failure due to the thyristor performance degradation is prevented. The device for protection and diagnostics is described for in-series thyristors.

EFFECT: improving protective functions and ensuring diagnostics for the three-phase rectifier with in-series connection of thyristors.

2 cl, 2 dwg