An Analysis of Transient States in the Power Supply System of a Selected Industrial Robot

Abstract

Industrial robots are controlled by dedicated controllers powered by a single-phase or three-phase power supply system. The main power parameters characterizing the power supply system of these robots are: nominal supply voltage (1-phase: 100–120 V, 200–240 V or 3-phase 200–575 V AC), frequency of the supply voltage (50 Hz or 60 Hz), the nominal power consumed by industrial robot. The dynamics of power consumption in the power supply system of the controlled robot can be studied by recording instan¬taneous values of voltages and currents in each phase of the power grid. In this article, results are presented for the measurements of mentioned instantaneous values for a chosen single-phase powered robot, taken by specialized recorder. The measurements obtained from the recorder allows the calculation of numerically various energetic values in the power supply system of the robot: peak-peak values, RMS values, coefficients of deformation and values of harmonic amplitudes (FFT), values of active, reactive and apparent power and the power coefficient (tg?). The analysis of the waveforms of the instantaneous values of voltage and current allows the determination of the occurrence of transient states during the work of robot axes and characterizing its duration and the range of value changes. The analyses conducted can be used to properly design the protection systems of the power supply system, the eventual selection of filters for higher harmonics, and to determine the effective power consumption of the studied robot. The analyses of the transient states which occurred during the work of the studied robot in this publication significantly expand the knowledge about the dynamics of power consumption and its possible impact on the quality of electricity in the power supply grid.