Method for starting a turbomachine

摘要

A method for increasing the operational flexibility of a turbomachine during a startup phase is provided. The turbomachine may include a first section, a second section, and a rotor disposed within the first section and the second section. The method may determine an allowable range of a physical parameter associated with the first section and/or the second section. The method may modulate a first valve and/or a second valve to allow steam flow into the first section and the second section respectively, wherein the modulation is based on the allowable range of the physical parameter. In addition, the physical parameter allows the method to independently apportion steam flow between the first section and the second section of the turbomachine, during the startup phase.

主权项

1. A method of unbalancing steam flow entering a turbomachine during a startup process, the method comprising:
a. providing a turbomachine comprising at least a first section and a second section, and a rotor partially disposed within the first section and the second section; b. providing a first valve configured for controlling steam flow into the first section; and a second valve configured for controlling steam flow into the second section; c. determining whether the turbomachine is operating in a startup phase; which begins when steam causes the rotor to rotate until steam is flowing through the first section and the second section; d. determining an allowable turbine operating space (ATOS) which approximates operational boundaries for each section of the turbomachine, wherein ATOS incorporates data on steam flow through each section, a thrust limit of each section, and an exhaust windage limit; e. determining an allowable range within ATOS of a physical parameter associated with the startup phase; f. modulating the first valve to control steam flow into the first section, wherein the modulation is partially limited, by the allowable range of the physical parameter; g. modulating the second valve to allow steam flow into the second section, wherein the modulation is partially limited by the allowable range of the physical parameter; and h. wherein ATOS, in real time, expands operational boundaries of the first section and the second section, and allows unbalanced steam flow between the first section and the second section of the turbomachine during the startup phase, wherein the method of unbalancing steam flow entering a turbomachine during a startup process comprises steps of increasing steam flow during the startup phase and expanding the operational boundaries and flexibility of the turbomachine.