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AssigneeWestinghouse Electric Corp.
InventorGerald E. Waldron
Estimating the term…
A steam turbine is provided with an electrohydraulic control system having an automatic control which includes a digital computer and further having a manual backup control for operating the turbine on automatic or operator switchover to backup control. The automatic control includes control elements and logic elements associated with valve control loops coupled to the turbine and high and low limits and other constants, setpoints and other parameters are characteristic to these control and logic elements and the interrelations among them and the turbine. A switch arrangement is provided for generating parameter value signals corresponding to changed values for the system parameters and for coupling the parameter value signals to the automatic control system where they are registered. The automatic control system is structured to reject invalid parameter value changes and to register only those parameter value changes which can be validly entered as part of the system structure. Once the switch arrangement is activated to initiate a parameter change, the automatic control system bumplessly rejects to the manual backup control so that the control configuration can be restructured while on-line turbine operation continues without substantial interruption. Once the parameter change process is completed, return can be made to automatic operation.
A system for operating an electric power generating plant comprising a steam turbine, means including a steam generating system for supplying steam to said turbine, a generator driven by said turbine and adapted to generate a predetermined electrical load for network operation with other generators, said turbine including a plurality of turbine sections, a predetermined throttle valve arrangement, a predetermined governor valve arrangement, said throttle and governor valves disposed to control the flow of steam between said steam generating system and said turbine, a control system including an automatic control having means for controlling said governor and throttle valves to control the turbine speed in accordance with input speed and speed change rate demands, said speed controlling means including control elements and associated logic elements characterized with other registered system parameters, said automatic control system further including means for controlling said governor and throttle valves to control the turbine load in accordance with input load and load change rate demands, said load controlling means including control and associated logic elements characterized with other registered system parameters, said automatic control further including means for generating system protection signals in accordance with predetermined input variable signals and in accordance with other registered parameters, a control panel having means for selectively generating parameter value signals to change selectively the values of said other parameters, means for switchably coupling the parameter value signals to said automatic control and for registering the parameter value signals in said automatic control in place of the selected ones of said other parameters so as to restructure said automatic control to function in accordance with the selected ones of said other parameters, a manual backup control for said governor and throttle valves, means for transferring the operation of said control system from said automatic control to said manual backup control when said generating and coupling means are operated to register parameter changes, and means for disabling said generating and coupling means from registering parameter changes in said automatic control unless transfer has occurred to said manual backup control.
A steam turbine control system for a large electric power steam turbine which drives a generator to produce electric power through breaker means and which is provided with a plurality of turbine sections and a predetermined throttle valve arrangement and a predetermined governor valve arrangement, said system comprising an automatic control having means for controlling said governor and throttle valves to control the turbine speed in accordance with input speed and speed change rate demands, said speed controlling means including control elements and associated logic elements characterized with other registered system parameters, said automatic control system further including means for controlling said governor and throttle valves to control the turbine load in accordance with input load and load change rate demands, said load controlling means including control and associated logic elements characterized with other registered system parameters, said automatic control further including means for generating system protection signals in accordance with predetermined input variable signals and in accordance with other registered parameters, a control panel having means for selectively generating parameter value signals to change selectively the values of said other parameters, means for switchably coupling the parameter value signals to said automatic control and for registering the parameter value signals in said automatic control in place of the selected ones of said other parameters so as to restructure said automatic control to function in accordance with the selected ones of said other parameters, a manual backup control for said governor and throttle valves, means for transferring the operation of said control system from said automatic control to said manual backup control when said generating and coupling means are operated to register parameter changes, and means for disabling said generating and coupling means from registering parameter changes in said automatic control unless transfer has occurred to said manual backup control.
Dependencies are inferred from the claim text.