Gas turbine systems are applied extensively in energy supplies to cover peak load requirements. The gas turboset must be accelerated by starting device up to 60%~80% of rated speed to ignite the gas turbine. Recently, the most favorable and economical starting device is the LCI(Load Commutated Inverter). The LCI runs up the gas turboset by feeding the generator as a synchronous motor. In this paper, we discuss in detail the driving principles and features of 183MW gas turbine system. During field application of LCI system, many tests have been conducted and the results were described in this paper. The test results will be considered as the important resources for development in future.