SOFIA (Reuters) -Bulgaria’s Kozloduy nuclear power plant is expected to reconnect its Unit 6 to the power grid by the end of the week, the country’s energy minister said on Tuesday. The state-owned plant had to shut down one of its two Russian-designed units late on Saturday after detecting a problem with the cooling system of the reactor’s power generator. Energy Minister Rossen Hristov said the repairs would take a bit longer than initially planned, but outlined that the problem was not in the nuclear part of the reactor and that there is no change in the radiation levels at the plant’s site…