초록 ▼

A turbine control system for changing over a throttle governing operation of a steam turbine to a nozzle governing operation thereof and vice versa by controlling control valves on the basis of a main control flow-rate request signal comprises function generators grouped according to the two governi

A turbine control system for changing over a throttle governing operation of a steam turbine to a nozzle governing operation thereof and vice versa by controlling control valves on the basis of a main control flow-rate request signal comprises function generators grouped according to the two governing operations and operating to produce function outputs in response to the opening degrees of the control valves. The function outputs are biased according to the two governing operaton and applied to respective high-value gates, the output signals of which are compared with the main control flow-rate request signal to control the opening degrees of the control valves in such a manner that the flow rate of steam introduced through the control valves into the steam turbine are maintained constant during the speed governing operation changing period.

대표청구항 ▼

A turbine control system for changing two speed governing operations of a steam turbine from a throttle governing operation to a nozzle governing operation and vice versa by controlling a plurality of steam control valves on the basis of a main control flow-rate request signal, which system comprise

A turbine control system for changing two speed governing operations of a steam turbine from a throttle governing operation to a nozzle governing operation and vice versa by controlling a plurality of steam control valves on the basis of a main control flow-rate request signal, which system comprises: a. first group of function generators for the throttle governing operation operatively coupled to said steam control valves for producing function outputs, as throttle governing feedback signals, in response to the opening degrees of said steam control valves, respectively; b. a second group of function generators for the nozzle governing operation operatively coupled to said steam control valves for producing function outputs, as nozzles goVerning feedback signals, in response to the opening degrees of said steam control valves, respectively; c. bias subtracting means connected to said function generators of the first and second groups for subtracting two bias signals from said feedback signals produced by said function generators of the first group and said feedback signals produced by said function generator of the second group to produce output signals, respectively; d. a high-value gate circuit provided for each steam control valve for passing the higher of said output signal applied thereto by said bias subtracting means; e. first means operatively connected to said steam control valves for producing a difference signal between said main control flow-rate request signal and the sum of signals representative of actual flow-rates of said steam control valves; and f. second means connected between said first means and said bias subtracting means for increasing, according to said difference signal, one of said two bias signal which is subtracted from said feedback signals produced for one of said two speed governing operations which is not one intended to effect, and for decreasing the other bias signal which is subtracted from the feedback signals produced for the other governing operation intended to effect, whereby during a period of changing said two governing operation, an output of said turbine is kept unchanged and no thermal shock is caused to said turbine.