A method of measuring rapid changes of low values of surface conductivity of dielectrics in the environment of electromagnetic interference of mains voltage and a device for performing this method of measuring

摘要

measurement of rapid changes ufeffzpu016fsob low values of surface conductivity dielektrik in environment electromagnetic interference network voltage is based on a reference voltage measurement on insulators and synchronization measuring pulses with periodic sinusoidu00e1lnu00edm the interfe rence when the surface is brought dielektrika voltage of designed parameters of rectangular pulse.the insulators tension created from measured surface dielektrika and rezistoru about the value of resistance is collected at specific time intervals, on the other hand, the potential before the measuring pulse and, on the other hand, just before its end.then on the basis of the difference of the measured values of the amplifier is obtained by diferenu010dnu00edho value corresponding to the value of the measured without the influence of electromagnetic interference of 50 hz, where the result is to allow a measurement of rapid changes of low conductivity surface surface dielektrika.device for measuring rapid changes of low surface conductivity dielektrik in environment electromagnetic interference network voltage includes a sensing element (1) for monitoring electromagnetic interference which is involved in the block (2) for monitoring electromagnetic interfe rence, whose first output is connected komparau010dnu00ed block (3) for the management of temporal sequences and block (4) generate pulses.the output of a rectangular pulse 1ms /. + -. 5 in and second output 10.mi.s /. + -.5 are connected to individual inputs block (6) of members, with another output block (2) for monitoring electromagnetic interference is linked to komparau010dnu00ed member (5) whose output is connected to the fourth input block (6) of membersthe first output block (6) is connected through the logic of block (7) modulation pulses with the output pulse of 0 to 300 mv on the surface of the block (8) of the voltage divider resistor surface.where the output of this block (8) of the voltage divider is connected through the resistor surface block (11) monitors voltage of insulators with a very high input signal input to an impedance of the first sample and hold amplifier (9) and the second sample and hold amplifier (10).the second entry for the management of sampling the first sample and hold amplifier (9) and a second input for the management of sampling other sample and hold amplifier (10) are connected with the corresponding output for driving the sampling block (6) of membersthe output of the first sample and hold amplifier (9) is connected through a block (12) of two series involved invertuju00edcu00edch amplifiers to invertuju00edcu00ed entry diferenu010dnu00edho amplifiers (13) in which neinvertuju00edcu00ed entry is connected to output the second sample and hold amplifier (10).the differential amplifier (13) through a block (14) elimininace random fluctuations in signal, and an output block (15) connected with the output low an impedance of device.