Voltage regulation has always been a problem in open pit mine power distribution systems due to long distance cables, continuously changing power distribution topology, and high power pulsating loads. Keeping voltage profile constant at load terminals in the mine pit is very important especially for shovels and drillers. Instantaneous voltage drop affects the shovel's operation triggering drives protections affecting severely mining production. This paper reports operational experience obtained in different copper mine facilities. Voltage regulation analysis of typical power distribution mine systems, showing voltage profile and the effects in shovels and drillers operation is presented. Different practical alternatives are proposed to improve voltage regulations, demonstrating than the use of series active compensation presents important advantages and becomes an interesting alternative.