Method for starting a system for generating electrical energy

摘要

The method involves combining a number of polygonal-shaped windings of a synchronous generator at low rotational speeds of a gas turbine, where the number of combined windings is lower than total number of generator windings. A matrix converter is provided with switching devices (L1-1-L3-1, L1-8-L3-8, L1-15-L3-15) i.e. thyristors. The windings are combined by blocking corresponding devices, where the low speeds correspond to 30 to 50 percentages of an operating speed of the turbine. The non-blocked devices are commutated at the low speeds in dependence on a load i.e. power supply grid. An independent claim is also included for an electrical energy generating system comprising a unit for combining a number of windings of a generator at low turbine rotational speeds.