Analysis of the sensivity of energy metering devices in face of Voltage Sags
Lucas Manuel Resende Rodrigues1; José Rubens Macedo Júnior1; Guilherme Leal Xavier2; Isaque Nogueira Gondim1; Paulo Henrique Oliveira Rezende1
1 Universidade Federal de Uberlândia; 2 Universidade Federal de Viçosa
Resumo
Not only industrial loads are subject to the voltage sags, but also the energy metering devices used by the distribution companies to quantify the power energy used by each customer. Due to its constructive aspect, which includes the use of electronic components, metering devices become "victims" of voltage sags and their operation are compromised by this disturbance. According to the issue previously discussed, two different tests were performed in laboratory and the main goal was to evaluate the sensitivity of some energy metering devices. The first test was performed, in order to create the sensitivity curves for each energy metering device. The second test measured the time between pulses, that represent the power energy consumed. When a voltage sag occurs, the time between pulses is increased, because metering devices could shut down depending on the voltage sag magnitude. In addition, it is important to know how long the device stayed inoperative. The inoperative time was determined by measuring the time between pulses in normal condition and the interval between pulses in face of a voltage sag. The data obtained made possible to determine the impact that this disturbance could cause in a distribution company invoice.
Palavras-chave: power quality; voltage sags; energy metering devices