METHOD FOR MONITORING TEMPERATURE OF ELECTROMAGNET WINDING AND DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2020 - IPC H01F7/08 H02H5/04 G01K7/06 

FIELD: electrical engineering.

SUBSTANCE: invention relates to electrical engineering and can be used for control of electromagnets (EM) of valves and switching devices. To prevent EM winding temperature exceeding permitted maximum value it is necessary to monitor it. Disclosed is use of control signals EM duty cycle, containing actuation section and holding section. A control signal of pulse modulation is formed on the holding section, and thus current is stabilized through the electromagnet winding at the level required for guaranteed retention of the electromagnet in the switched on state. In the holding section at steady-state average value of current in winding there determined is average value of voltage on winding, this value is saved, which is obtained at first switching-on of electromagnet, when temperature of winding is equal to known value of ambient temperature, which is also stored. In each next operating cycle, current average voltage value on winding is determined at holding section and winding temperature value is determined on current operating cycle by formula

,

where T_t is value of winding temperature in current operating cycle; T₀ is ambient temperature value during first EM connection; U₀ – average value of voltage on winding at first connection of EM; U_t is average value of voltage on winding in current operating cycle; α is winding wire resistance temperature coefficient.

EFFECT: technical result consists in improvement of noise immunity and accuracy due to elimination of influence of change of supply voltage EM and inductance of winding on determination of winding temperature, as well as reduction of requirements to productivity of microcontroller and volume of required memory.

6 cl, 5 dwg