This paper focuses on achieving traceability of high-voltage measurements up to 200 kV at the Egyptian National Institute of Standards. The measuring system consists of an AC/DC voltmeter and a universal resistive/capacitive high-voltage divider. The voltmeter shows the measured voltage values while considering an actual scale factor of the voltage divider. The used divider ensures stable capacitance for AC voltage measurements and an additional resistive parallel path for DC voltage measurements. Both the divider and the voltmeter are calibrated in AC and DC modes. All uncertainty components are taken into account to obtain the near-actual values of the measuring system with an acceptable accuracy. The calibration results in traceability …show more content…
The most used method to calibrate the division ratio is to get the ratio between actual voltages on the high-voltage and low-voltage arms of the divider [5-7]. In other words, the true voltage values of a high-voltage source are obtained from multiplication of the actual voltages on the low-voltage arm times the actual ratio of the division.
The precision of high-voltage DC dividers mainly relies on the resistive design, while high-voltage AC dividers are commonly based on the capacitive design [8]. In this regards, Josephson Voltage Standard (JVS) has been used for many years as a DC voltage standard with ultimate accuracy [9-11].
Traceability of DC and AC voltage measurements up to 100 kV was previously realized at National Institute of Standards (NIS) via a DC-JVS [4, 9]. In the studies presented by El-Rifaie et al. in [4] and Abdel Mageed et al. in [9], the uncertainty of the DC and AC high-voltage measurements up to 100 kV has been significantly enhanced after achieving traceability from the JVS.
In this work, traceability dissemination of DC and AC voltages up to 200 kV on the basis of the traceable 100 kV measurements is obtained using enhanced calibration method. The high-voltage system considered in this study consists of two main parts, namely the divider and display, in which both of them are calibrated. A two-stage Haefely Trench high-voltage AC source (PZT-100) is used to
Procedure: I used a ruler, thermometer, and scale to take measurements. I used a graduated cylinder, short step pipet, scale, and ruler to determine volume and density. I used a volumetric flask, graduated pipet, pipet bulb, scale, and glass beaker to determine concentrations and densities of various dilutions.
5.95ohms, 105degrees-9.76ohms, 120degrees-5.24ohms, 135degrees-9.20ohms, 150degrees-12.80ohms, 165degrees-16.58ohms, 180degrees-5.24ohms. These results varied, it appears as though when I made a slight increment to the degrees it made a drastic effect to the meter
kindly find below the information for this meters and we will take the reading next week to check and compare between analog and digital meters to get final result
measurements of three-phase voltage and current samples obtained from the PSCAD/EMTDC. Fig. 8 depicts the 220 kV, 50 Hz simulated system one-line diagram. The other related parameters of the simulated system are shown in Table 1, transmission lines are assumed completely transposed. Fig. 9 & 10 show 3ph voltages and currents waveforms for 3ph to ground fault at 50% of the second line without and with UPFC respectively. It is clear that when UPFC is involved in the fault loop, the the voltage and current signals would be deviated from the actual value.
6) Change the location of the positive charge to at least six widely different distances from the equipotential sensor. Record the voltage reading and distance at each location.
was derived and a relationship between Vinv and Vc was obtained (see Fig. 2). Applying voltage balance
Theoretical analysis is one of the most significant phases of the project. The high resistance measurement system developed during this project is primarily based
The comparison of above three algorithms for 8, 16 and 32 bit operands with corresponding voltage and frequency are tabulated in table I
Average accuracy of the above meter. Solution: Compute the Kh of the standard used For Light Load : Kh = 0.6 X 240 = 1.2 120 For Full Load : Kh = 0.6 X 240 X 50 = 12 120 5 a) Compute the Light Load rev. based on the meter and standard CR = Kh(MUT) X Rev.(MUT) X V(std) = 28.8 X 1 = 24 Kh(std) X No. of Element X V(MUT)
To do this, voltage division was used two times, an example of voltage division can be seen below in Equation 1. To create a
Change the location of the positive charge to at least six widely different distances from the equipotential sensor. Record the voltage reading and distance at each location.
The impacts of a high-level EMP on the electric grid are still not fully understood, but are being
First, we put a long white rope and two fiberglass long tape in the ground. Measuring tape gave us the total distance of 18.4 m. Then, we set up a yellow plastic survey peg in middle of the ground. Second, in conducting an expanding-spread Wenner survey (see Figure 4), we move all electrodes along a straight line after every reading. So, the spacing between electrodes remains equal and takes on certain preselected values. In addition, we pushed the electrodes by using hammers. Next, we set up the cord clips and battery cables in the resistivity meter and the electrodes (Figure 1 and 2). Lastly, we used the computer
R/2R ladder present a easy way to convert digital voltage/information to analog for output. The R/2R ladder needs consideration to in what way the device is stated when applying to actual applications. In the makings of R/2R ladder, output faults due to resistor tolerances are most of the time not considered
In the 19th century, Samuel Hunter Christie invented the diamond method for circuits, the initial idea to the Wheatstone bridge. However, bridge circuits, circuits with parallel resistors, bridged by a branch between them, were used to measure small voltages; but, the Wheatstone bridge is used to measure an unknown resistance using all the others three known resistance in the circuit. During the lab, the Wheatstone Bridge concept for a bridge circuit was used to determine the unknown resistor in the circuit, see in figure 1. The objective was to measure the voltages between points on the branch between the first two resistors in series on top and bottom ones, in which were connected in parallel. Thereafter, test the voltage calculated at different temperatures, those being room temperature, ice water and hot water; by using a thermistor in the circuit, that helps calibrate the Wheatstone bridge as a thermometer.