Procedure for the development of the software supported acquisition system for generating signals applied to testing of instruments for measurement and analysis of the standard electrical power quality (PQ) parameters is presented in this paper. Described solution performs generating standard three-phase voltage waveforms, including possibility for simulation of the various PQ disturbances typical for real electrical power distribution networks. This generator is functionally based on virtual instrumentation concept, including control software application in graphical package LabVIEW and data acquisition board NI PCI 6713. Software support of this generator provides definition and graphical presentation of the reference voltage waveforms for testing. Number of the control functions and switches implemented on the front panel of the developed signal generator enables adjustment of the basic parameters for definition, presentation and signal generating. The presented solution is capable to generate long-time and short-time signal test sequences, including all types of the PQ disturbances defined according to European quality standard EN 50160. [Projekat Ministarstva nauke Republike Srbije, br. TR 32019 i br. III 42009]