Rancang Bangun Alat Deteksi Sag Tegangan Menggunakan Sistem Data Logger

This research discusses the design and manufacture of a voltage sag detection device using a data logger system. Voltage sag detection device to detect the presence of voltage sag which is one of the power quality problems in industrial electrical systems. Voltage sag can cause disturbances in electronic components that are sensitive to changes in voltage values. In this device, the voltage sag is detected using a voltage sensor by reading the RMS voltage from the PLN 220V AC source, then it is converted into a digital signal. The digital signal is sent to the ESP32 module to be processed and outputs a voltage value which is then displayed on the LCD Display. The voltage value data collection is carried out every <10ms and the data taken is the voltage value <90% of the rms voltage. The data taken is then saved to a micro SD card and displayed on the LCD Display. Several tests were carried out to ensure the performance of the voltage sag detector as designed. By switching the 110 / 220VAC transformer connected to the voltage sensor for 10 seconds, 12 seconds and 17 seconds. Based on these tests, the voltage sag detector can read and store the voltage sag data when the voltage read is below 90% of the rms voltage.

Combining DVR and UPS Techniques for an Uninterruptable Supply of Ultra-Sensitive Non-Linear Appliances

The paper deals with an application of combined techniques of dynamical voltage restorer (DVR) and uninterruptible power supply (UPS) that make possible both the short voltage sags compensation, as well as longer power supply interruptions, under the simultaneous operation of equipment and network. This is enabled mainly by an instantaneous voltage sag detection, quick bidirectional over-switches, and an instantaneous control method of the output voltage. This needs a fast control method, which can provide a voltage recovery for phase-sensitive loads during several calculation steps, so the dead-beat regulator is used. Such a system even compensates for the influence of non-linear loads on the power supply network without a change of a phase and amplitude of the supply voltage. The simulation results in Matlab/Simulink, as well as real experiments and their comparison results, are given in the paper.

A Fast and Accurate Method for Power System Voltage Sag Detection

In order to mitigate the effect of voltage sag on sensitive loads, a dynamic voltage restorer (DVR) should be used for this purpose. The DVR should be accompanied with a fast and accurate sag detection circuit or algorithm to determine the sag information as quickly as possible with an acceptable precision. This paper presents the numerical matrix method as a distinctive candidate for voltage sag detection. The design steps of this method are demonstrated in detail in this work. The simulation results exhibit the superiority of this technique over the other detection techniques in term of the speed and accuracy of detection, simplicity in implementation, and the memory size. The results also accentuate the recognition capability of the proposed method in distinguishing different types of voltage sag by testing three different voltage sag scenarios.