Capacitance Voltage Transformer: The errors due to harmonic voltages can be eliminated by the use of capacitive voltage dividers with an electrostatic voltmeter or a high impedance meter such as a T.V.M. If the meter…
Series Capacitance Voltmeter: To avoid the drawbacks pointed out earlier, a Series Capacitance Voltmeter is used instead of a resistor for a.c. high voltage measurements. The schematic diagram is shown in Fig. 7.10. The current…
Series Impedance Voltmeter: For power frequency a.c. measurements the Series Impedance Voltmeter may be a pure resistance or a reactance. Since resistances involve power losses, often a capacitor is preferred as a series reactance. Moreover,…
AC Field Strength Meter: AC Field Strength Meter is usually measured by introducing a small fixed capacitance probe into the field area and measuring the induced charge on it. Since the electric field between the…
DC Electric Field Strength Meter: The DC Electric Field Strength Meter strength E can be measured by using (i) variable capacitor probe or generating voltmeter or (ii) a vibrating plate capacitor. These devices determine the…
Generating Voltmeter Principle and Construction: High voltage measuring devices employ generating principle when source loading is prohibited (as with Van de Graaff generators, etc.) or when direct connection to the high voltage source is to…
Series Resistance Microammeter: High d.c. voltages are usually measured by connecting a very high resistance (few hundreds of megaohms) in Series Resistance Microammeter as shown in Fig. 7.1. Only the current I flowing through the…
Tripping of Impulse Generator: In large impulse generator, the spark gaps are generally sphere gaps or gaps formed by hemispherical electrodes. The gaps are arranged such that sparking of one gap results in automatic sparking…
Generation of Impulse Current Generator Output Waveform: Lightning discharges involve both high voltage impulses and high current impulses on transmission lines. Protective gear like surge diverters have to discharge the lightning currents without damage. Therefore,…
Generation of Switching Surges: Nowadays in extra high voltage transmission lines and power systems, switching surges is an important factor that affects the design of insulation. All transmission lines rated for 220 kV and above…
