METHOD FOR DETERMINING THE RESPONSE TIME OF THE PROTECTION OF CURRENT-CARRYING CONTACT CONNECTIONS OF SWITCHING DEVICES AGAINST OVERHEATING Russian patent published in 2023 - IPC H02H5/04 

FIELD: electrical engineering.

SUBSTANCE: method includes monitoring the deviation from the maximum allowable temperature value of the contact surface of the current-carrying contact connection most susceptible to overheating as a part of the switching device and generating a signal when the contact surface reaches the maximum allowable temperature. In the monitoring mode, the value of a rectangular current pulse is measured and compared with a predetermined threshold value, while taking into account the value of the conditionally contact dynamic resistance. If the current exceeds its threshold value, the temperature control of the contact surface is carried out in the dynamic monitoring mode at the heating time interval of the contact connection according to a linear law, then the temperature values measured during dynamic monitoring of the external surface of the contact part available for direct measurements are recalculated, then the mathematical expectation of the values of the conditionally contact dynamic resistance is calculated and the moment of time before switching off the switching device is determined.

EFFECT: increase in the accuracy and speed of determining the response time of the protection.

1 cl, 5 dwg, 5 tbl