This article focuses on the developing of a Portable Voltage Regulator for Low Voltage Networks (PVRL VN), for single phase, two phases and three phases networks, which envisages meeting the regulations, given that the time established by the regulatory standards is a factor that limits the planning and the execution of corrective actions. The first PVRLVN was developed inside a Research & Development Project financed by AES Eletropaulo, an energy distribution company with more than 5,8 million customers in the greatest city of Brazil. This PVRLVN, with the portability to be installed on a pole near customers with voltage problems, was developed, designed and tested in a laboratory and also in a real grid to be a temporary equipment that would adjust the voltage of the grid continuously to the right level until a definitive solution be done by the utility, avoiding penalties. The developed regulators were installed in several different locations in actual network of the AES Eletropaulo and AES SuI, both Brazilian local distribution companies.