Spark Gap Measurement Method - Measurement of High Voltage & High Current - High Voltage Engineering

TL;DR

Spark gaps can be used to measure high DC, AC, and impulse voltages, with the breakdown of the gap independent of the voltage waveform.

Transcript

hello friends welcome back to the lecture series on high voltage engineering this is the last topic of this particular chapter of this high voltage engineering that is a spark gap for measurement of high dc ac and impulse voltage impulse voltage is also called as a peak values so a spark gap can be used for the measurement of these high dc ac and i... Read More

Key Insights

• ⚡ Spark gaps can be used to measure high DC, AC, and impulse voltages.
• 💖 The breakdown of the spark gap is independent of the voltage waveform and occurs when the electric field, current density, and temperature exceed a certain threshold.
• 📣 Sphere gaps are commonly used for voltage measurements, while rod gaps provide approximate measurements.
• 🥶 The surface of the spheres in a spark gap should be smooth and free from dust, grease, or coating.
• ⚡ The spacing between the spheres or rods determines the breakdown voltage and should be carefully chosen.
• ⚡ A series resistance is used to limit the breakdown current and suppress unwanted oscillations in the voltage source.
• 📣 Spark gaps are reliable for voltage measurements when the gap configuration and atmospheric conditions are controlled.

Questions & Answers

Q: What is a spark gap and how is it used to measure high voltages?

A spark gap is a device that allows the measurement of high DC, AC, and impulse voltages. The breakdown of the spark gap indicates the voltage being measured.

Q: What factors affect the breakdown of a spark gap?

The breakdown of a spark gap is affected by humidity, air density, the electric field, current density, and temperature in the gap.

Q: What are sphere gaps and rod gaps?

Sphere gaps consist of two identical spheres with a known spacing, while rod gaps use two rods with a known length and spacing. Sphere gaps are commonly used for voltage measurements, while rod gaps provide approximate measurements.

Q: How does a spark gap measurement work?

The spark gap is connected to a voltage source, and the applied voltage is increased until a spark occurs in the gap. The spark over voltage is measured to determine the voltage being measured.

Summary & Key Takeaways

• Spark gaps can measure peak values of high DC, AC, and impulse voltages.

• The breakdown of the spark gap occurs when the electric field, current density, and temperature in the gap increase.

• Sphere gaps are commonly used for voltage measurements, while rod gaps are used for approximate measurements.