CAPACITIVE VOLTAGE DIVIDER DESIGN FOR HIGH VOLTAGE MEASUREMENT IN 150KV ELECTRICAL EQUIPMENT TEST

• Main Author: Muhammad Setyaman, Harits
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/51147
• Institution: Institut Teknologi Bandung

High-voltage equipment has a large stray capacitance to ground so that high-voltage equipment also has a large voltage gradient. Therefore, high voltage measurement is necessary to ensure perfect safety for the personnel and equipment in the vicinity from the overvoltage. The utility of high voltage measurement is not limited to ensuring safety, but high voltage measurement can also be used to test electrical equipment that requires high voltage. In this paper, we will discuss the capacitive voltage divider as a conversion device in high voltage measurement systems that can be used in the withstand voltage test of 150kV high voltage equipment. Capacitive voltage dividers are chosen because of their flexibility in measuring high voltages with a suitable capacitor. Capacitive voltage dividers are made using two groups of capacitors, namely the high voltage capacitor group with a capacitance value of 0.80 nF, a voltage rating of 600kV and a group of low voltage capacitors with a capacitance value of 4.4 µF, a voltage rating of 100V. The capacitive voltage divider design is determined by means of an electric field simulation. From the results of the electric field simulation, to be able to measure voltages up to 325kV as expected, it was determined that the high-voltage capacitor group needed a distance of 7 cm with an additional ring with diameter 24 cm between the capacitors. After that, a capacitive voltage divider is made and tested. From the results of the linearity test which was carried out by comparing the capacitive voltage divider made with the reference measurement system, the calibration result scale factor was 4933 with an extended uncertainty value from the high voltage measurement of 0.93%.