DEVICE TO PROTECT EQUIPMENT AGAINST PULSE OVERLOADS Russian patent published in 2012 - IPC H02H9/00 

FIELD: electricity.

SUBSTANCE: device comprises a varistor 4, a controlled spark gap 6 with a parallel connected control unit 5 and a current sensor 7. The first output of the varistor 4 and the potential lead of the gap 6 are connected to an input terminal 2 of the protected equipment. A non-potential output of the gap 6 is connected to a working grounding wire 3, the second output of the varistor 4 via the current sensor 7 is connected to the working grounding wire 3. The output of the current sensor 7 via the control unit 5 is connected with a control electrode of the gap 6. A potential output of the controlled spark gap 6 is connected to a terminal 1 of a phase voltage wire via an additionally introduced low pass filter 8, the cut frequency value of which does not exceed a value reverse to the varistor actuation time value. The gap 2 is a controlled vacuum gap. The control unit 5 comprises a voltage sensor 9, a timer 10, an integrator 11, a comparison device 12, a source 13 of reference voltage with a falling outer characteristic and an ignition unit 14.

EFFECT: invention provides for equipment protection against electromagnet pulses of anthropogenic and natural origin of a nanosecond duration, possibility to restore grid voltage on power transmission lines.

3 cl, 6 dwg