| 摘要 |
PURPOSE:To control erosion and thermal stress by obtaining a change over device, capable of automatically performing throttling speed governing at starting time and shifting to nozzle cut-out speed governing without fear of generating load change and further performing nozzle cut-out speed governing even in medium and low load area. CONSTITUTION:At starting time of a steam engine, each speed governing change-over instrument 4a-4d is changed over to combined function operation instruments 2a-2d side and, after converting a flow signal from an output control operation instrument 1 into an opening requirement signal of combined governing by each operation instrument 2a-2d, said signal is inputted to steam adjusting valve opening/closing controllers 5a-5d. In case load is raised and a flow signal from the output control operation instrument 1 grows above correspondence with high load area and this condition is detected by a change-over command instrument 6, speed governing instruments 4a-4d are changed over to nozzle function operation instruments 3a-3d side by said change-over command instrument 6 at the time of inputting a change-over command signal. Nozzle cut- out speed governing operation is performed hereafter. |
