| 摘要 |
PURPOSE:To perform the best control operation in all load zones, by automatically varying the integration time and differentiation time of a PID controller in proportion to the reciprocal of the quantity of a load. CONSTITUTION:A steam-flow equivalent signal Fs is inputted to a generating element I1 for an inverse function to generate an integration time signal TI, which is sent to an element 2 for PID control. Said singla Fs is also inputted to another generating element D3 for an inverse function to generate a differentiation time signal TD, which is sent to the PID control element 3. The PID control element 3 inputs the integration time signal TI and differentiation time signal TD, and uses an integration time valve[TI]and a differentiation time value [TD]which correspond to a current flow of steam to determine the opening extent of a spray value of a process variable 5 by PID arithmetic from the temperature set value of a desired value and an overheat exit steam temperature detection value of a controlled variable 7, controlling a controlled system process 6 so that the controlled variable 7 coincides with a desired value 4. |
