Sinusoidal AC source

A sinusoidal ac source with a peak voltage of 20.0 V was placed in series with a 15 kfl resistor and a 0.0080 pF capacitor. Use a spreadsheet to calculate the peak current, the phase angle, and the voltage drop across each of the components for frequencies of 75 Hz, 750 Hz, 7.5 kHz. and 75 kHz... 

When calculations for a much longer time period are required, a source should be represented as a sinusoidal AC source. In the case of fault clearing and load rejection overvoltages, the observation time exceeds 1 s, and the mechanical and electrical characteristics (including generator control) of the generator should be considered. In such a case, the sinusoidal AC source is not appropriate, and Park s generator model is often used. 

The dielectric relaxation properties in nano-PS with different thicknesses have been investigated recently over a wide range of frequency and temperature [160,161]. The dielectric properties of the PS samples were measured in the 20-Hz to 1-MHz frequency range and in the 173 to 493 K temperature interval. For all the dielectric measurements, the amplitude of a sinusoidal ac-voltage source was maintained 1 V so that the average electric field across our sample was of the order of hundreds of volts per centimeter depending on the sample thickness. It was verified that the response was linear with respect to the ac-voltage amplitude such that a linear response analysis could be utilized for our sample. 

In the previous theoretical analysis, the source voltage was assumed to be a step function (or DC) voltage. This assumption is accurate enough as long as the observation time of a switching surge is less than 1 ms. If the observation time exceeds 5 ms, a sinusoidal AC voltage source should be taken into account. This makes the Laplace transform quite complicated. 

Most power systems in the oil industry do not have variable speed drives and so the AC supply is a highly dependable and simple source of sinusoidal voltage and current. Little or no harmonics are present. If a large variable speed drive is required, and an inverter or thyristor controller of some form is used, then the combination of these equipments will cause harmonic currents to be drawn from the supply. 

By means of the inverse piezoeleetric effect, the ferroelectret samples can also be used as sound sourees. Measurement of the sound pressure on axis in the far field yields the inverse 33 eoeffieient. In this method, the ferroelectret sample, driven sinusoidally with an AC voltage, is used as sound sources and can be modeled as a circular piston mounted in an infinite baffle (Kressmann 2001b Sessler and Hillenbrand 2013). The on-axis sound pressure p(r) generated by a circular piston with radius R and area TtR, mounted in an infinite baffle, at a distance r is given by... 

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