Corona Discharges: If the electric field is uniform, a gradual increase in voltage across a gap produces a breakdown of the gap in the form of a spark without any preliminary discharges. On the other…
Paschen Breakdown | Paschen's Law | Paschen curve It has been shown earlier (refer Sec. 2.6) that the Paschen Breakdown criterion in gases is given as where the coefficients α and γ are functions of E/p, i.e…
Streamer Theory of Breakdown in Gases: Townsend mechanism when applied to breakdown at atmospheric pressure was found to have certain drawbacks. Firstly, according to the Townsend theory, current growth occurs as a result of ionization…
Formative Time Lag: Formative Time Lag - In the previous section, the mechanism of spark breakdown is considered as a function of ionization processes under uniform field conditions. But in practical engineering designs, the breakdown…
Experimental Arrangement to Measure Ionization Coefficients α and γ: The Experimental Arrangement to Measure Ionization Coefficients is shown in Fig. 2.2. The electrode system consists of two uniform field electrodes. The high voltage electrode is connected…
Breakdown in Electronegative Gases: It has been recognized that one process that gives high breakdown strength to a gas is the electron attachment in which free electrons get attached to neutral atoms or molecules to…
Townsend Current Growth Equation: Referring to Fig. 2.1 shows the Townsend Current Growth Equation. let us assume that n0 electrons are emitted from the cathode. When one electron collides with a neutral particle, a positive ion and…
Ionization Processes: A gas in its normal state is almost a perfect insulator. However, when a high voltage is applied between the two electrodes immersed in a gaseous medium, the gas becomes a conductor and…
Collision Process in Gases: An electrical discharge is normally created from unionised gas by Collision Process in Gases. These processes are mainly gas processes which occur due to the collision between the charged particles and…
Voltage Transformer Earthing: In this method of neutral earthing, the primary of a single-phase Voltage Transformer Earthing is connected between the neutral and the earth as shown in Fig. 26.17. A low resistor in series…
