Series Impedance Ammeter - High Voltage Engineering

TL;DR

This content discusses the various methods of measuring high AC voltage using impedance, specifically focusing on the series capacitance with ammeter method.

Transcript

hello friends welcome back to the discussion on this series impedance with ammeter in the previous lectures we discussed the measurement of high dc voltage in measurement of high ac voltage there are five different methods of the measurement of high voltage whenever we need to do the measurement of high voltage that voltage is to be reduced to the ... Read More

Key Insights

• ⚡ Measurement of high AC voltage requires reducing the voltage to allow for accurate measurement using a voltmeter or ammeter.
• 🥺 Using a pure resistance for measurement leads to power loss, temperature variation, and the influence of residual inductance and stray capacitance.
• ❓ The series impedance with ammeter method overcomes these limitations by using a series capacitor instead of a resistor.
• ⚡ The series capacitance voltmeter is suitable for measuring pure sinusoidal AC voltages without harmonics present.

Questions & Answers

Q: What is the purpose of reducing the value of high voltage before measurement?

The high voltage needs to be reduced so that a voltmeter or ammeter can accurately measure it. High-value voltmeters and ammeters are difficult to develop, so reducing the voltage allows for easier measurement.

Q: What are the limitations of using a pure resistance for high voltage measurement?

Pure resistance leads to power loss and variation with temperature. Additionally, residual inductance and stray capacitance can affect the current passing through the measurement unit, leading to inaccurate readings.

Q: How does the series impedance with ammeter method overcome the limitations of pure resistance measurement?

By using a series capacitor instead of a resistor, the method avoids power loss and temperature variation. It also improves the accuracy by minimizing the influence of residual inductance and stray capacitance on the current passing through the measurement unit.

Q: How is the measurement of high AC voltage achieved with the series capacitance voltmeter?

The series capacitance voltmeter utilizes a series capacitor connected to the high voltage terminal. A rectifier ammeter is used as the indicating instrument, and it is directly calibrated in high voltage rms value for accurate measurement.

Summary & Key Takeaways

• There are five different methods for measuring high AC voltage, and this content focuses on the series impedance with ammeter method.

• In this method, a resistor and inductor are connected in series, and the series combination is connected in parallel with a capacitor.

• The use of a series capacitor instead of a resistor helps overcome the drawbacks of using a pure resistance for AC voltage measurement.