Abstract: Abstract:The monitoring system lower position machine of Guangzhou PumpedStorage Hydropower Plant had been put into operation for more than 20 years. The parts for repair are not available. So it is necessary to upgrade and reform the lower position machine and to use new equipment and new technology to improve the equipment operation reliability. The reformation conditions were combed, the device types were selected, and the reformation process was designed. Then a set of reformation schemes was designed. To implement the schemes can solve a series of reformation problems, and meanwhile, as short as possible equipment stoppage time is needed.

Key words: Keywords:hydropower plant, monitoring system, reformation of lower position machine, device type selection