APS control method for gas turbine start-up by SFC

In recent years, static frequency converters (SFCs) have been utilized to start gas turbines in high-efficiency gas turbine combined cycle (GTCC) power plants. A gas turbine is started using a generator with a single-shaft arrangement that is rotated using the electric power fed from the SFC. Because the rotor position of the generator is important for controlling the SFC operation, a position sensor is installed beside the rotor shaft. However, the installation and adjustment of a position sensor, a mechanical device, is more difficult than of an electrical device. Therefore, a sensorless control method called advanced position sensor (APS) was developed. APS calculates the phase of the induced voltage using the generator terminal voltage and armature current. In this paper, we describe the start-up of a gas turbine of a real plant using SFC equipped with APS. Further, we report on the availability of APS by this start-up result.