What do you mean? PC and dB?

PC - pico coloumb

dB - Decibel

Dear Rajendra Kumar Mohapatra, I would say that nowadays you should not worry about PD in DB. This unity was used in the past when the same instrument was used for RIV and PD measurements. Even the quantification of PD only in amplitude using PC (apparent charge) as unit is a poor technique nowadays. I would suggest you to deal with 2D or 3D digital maps related to PD measurements provided by digital PD measuring systems where you can obtain more valuable information such as PD histogram x phase or time of occurrence and associated statistical analysis, for instance. Please check IEC 60270: HIGH-VOLTAGE TEST TECHNIQUES — PARTIAL DISCHARGE MEASUREMENTS. Best Regards, Orsino

PC is a term such as repitition rate, phase angle, discharge quantity in electric partial discharge measurement.

dB is a term such as  sensitivity, discriminator's gain in PD signal measurement by acoustic emission method.

Therefore  the correlation in the values of PD in terms of PC and dB  are not.

there is no standard which restricts the measurement of partial discharge in terms of dB  or in terms of pc .

there are instruments which measure partial discharge in "" pc "and some instruments measure the "dB ""-

even though dB is primarily a measure of noise level - it is also related to partial discharge inside transformer

So , in the course of operation and interaction - the subject of correlation comes up

Hi,

from my experience High Voltage is an issue of Electrotechnics (ELT).

In ELT are used Volts, kVolts and also Mega Volts to characterize HV pulses.

dB are a possible measuring unit of Tension V (dBuV) and Power (dBm) in of some instruments used more in Electronics or Telecommunications

So, if you have such an instrument, please check the conversion between

Volt and dB microVolt (dBuV)

http://www.eeweb.com/toolbox/rf-unit-converter

in example, in a 50 Ohm measuring system

120 dBmicroVolt = 1 V (rms)

All the Best, Alberto

pC is purely determined by the type of sensor u are using.If u are using HFCT then it dependents on the tranfer impedance value, bandwidth and measured amplitude in (V or mV). HFCT usually has bandwidth 20 Mhz (being very optimistic). However when capacitive sensor is used then the impedance and capacitance of the antenna/sensor can be measured using network analyser and with those values pC can be calculated. Basically u dont need the value in dB for PD. Usually dB is measured for continuous signal(RF power, noise, acoustic) and not pulse type signal.

Previously I was haunted by this question too. Now I'm with the opinion that under certain controlled condition, the correlation can be linear. However for complex, a real world scenario (e.g. in power transformer), there are evidences that linear relationship is not possible.