The document discusses high voltage measurement techniques including using a voltage divider rule to measure high voltages. It explains that for direct current, electric lines of force are static but for alternating current, charge density is a periodic function of time. It also covers energy storage in capacitors using the equation that energy density equals one half the permittivity of free space multiplied by the electric field strength squared. Safety clearances for high voltage equipment are discussed including the air gap and spark point height above ground or other objects.

1. High Voltage Measurement

2. Ohmic that obeys ohm’s law

3. Voltage divider rule
V2= HV [R2/ (R1+R2)]

4. For DC
Electric lines of force
By induction process
For HVAC, the sigma (charge density) is function of time but for HVDC, sigma is function of charge

5. Periodic function
After applying derivative
Product rule of
derivative

6. i=C dVc/dt
Freq of sync motor

10. Energy storage in capacitor
or simply work done in raising the potential of
capacitor to V volts
As,
C= Ɛ A/d
So,
W= 1/2 (ƐA/d) V2
= 1/2 (Ɛ A/d) (E.d)2
=1/2 Ɛ Ad E2
= 1/2 V Ɛ E2
Energy Density W/V = 1/2 Ɛ E2

13. Air Gap
known
distance
Apply Voltage
here
to be measure

17. A = height of Spark point from ground
B = clearance from the nearest body/object

20. Lab Link
• https://www.youtube.com/watch?v=gAKNd5l
9CaU&list=PLGuRMgUXXdPsfOjwueP6Y_FoMu
Tozwq6J&index=10