Abstract: A start control unit for a steam turbine plant, wherein inputting a measured value of a steam temperature fed to a steam turbine, a measured value or an estimated value of a rotor temperature of the steam turbine, and a measured value of a casing temperature of the steam turbine, and controlling a steam flow rate so as to increase the steam flow rate fed to the steam turbine when a difference between the steam temperature and the rotor temperature is smaller than a first regulated value and a difference between the rotor temperature and the casing temperature is a second regulated value or larger.

Abstract: Disclosed is a steam turbine power plant adapted to start operating safely even if prediction accuracy of its startup constraints cannot be obtained. The system calculates predictive values and current values of startup constraints of a steam turbine from process variables of plant physical quantities, next calculates in parallel both a first control input variable for a heat medium flow controller based on predictive values, and a second control input variable for a main steam control valve based on the current values, and while preferentially selecting the first control input variable, if the first control input variable is not calculated, selects the second control input variable instead. After the selection of at least one of the first and second control input variables, the system outputs an appropriate command value to the heat medium flow controller and the main steam control valve according to the kind of selected control input variable.

Abstract: Disclosed is a steam turbine power plant adapted to start operating very efficiently by highly accurate look-ahead control of a plurality of its startup constraints.

Abstract: A start control unit for a steam turbine plant, wherein inputting a measured value of a steam temperature fed to a steam turbine, a measured value or an estimated value of a rotor temperature of the steam turbine, and a measured value of a casing temperature of the steam turbine, and controlling a steam flow rate so as to increase the steam flow rate fed to the steam turbine when a difference between the steam temperature and the rotor temperature is smaller than a first regulated value and a difference between the rotor temperature and the casing temperature is a second regulated value or larger.

Abstract: Disclosed is a steam turbine power plant adapted to start operating very efficiently by highly accurate look-ahead control of a plurality of its startup constraints.

Abstract: Disclosed is a steam turbine power plant adapted to start operating safely even if prediction accuracy of its startup constraints cannot be obtained. The system calculates predictive values and current values of startup constraints of a steam turbine from process variables of plant physical quantities, next calculates in parallel both a first control input variable for a heat medium flow controller based on predictive values, and a second control input variable for a main steam control valve based on the current values, and while preferentially selecting the first control input variable, if the first control input variable is not calculated, selects the second control input variable instead. After the selection of at least one of the first and second control input variables, the system outputs an appropriate command value to the heat medium flow controller and the main steam control valve according to the kind of selected control input variable.

Abstract: A steam turbine power plant includes heat-source equipment that heats a low-temperature flow by applying a heat medium and thus generates a high-temperature flow, a steam generator using the high-temperature flow generated by the heat-source equipment, a steam turbine driven by the steam generated by the steam generator, an electric generator that converts rotational motive power of the steam turbine into electric power, a heat-medium controller that controls a supply rate of the heat medium supplied to the heat source equipment, a low-temperature flow controller that controls a supply rate of the low-temperature flow supplied to the heat-source equipment, a prediction device that predicts startup constraints of the steam turbine from control input variables of the controllers when the steam turbine is started, and a control input variables setter so as to prevent data predictions by the prediction device from exceeding limit values of startup constraints.

Abstract: A pin photodiode having a structure capable improving the frequency response and the saturation output while maintaining the effective internal quantum efficiency and CR time constant. A pin photodiode is formed by: a first semiconductor layer in a first conduction type; a second semiconductor layer in a second conduction type; a third semiconductor layer sandwiched between the first and second semiconductor layers, having a doping concentration lower than those of the first and second semiconductor layers; a fourth semiconductor layer in the first conduction type, provided at one side of the first semiconductor layer opposite to a side at which the third semiconductor layer is provided; and a cathode electrode and an anode electrode connected directly or indirectly to the second semiconductor layer and the fourth semiconductor layer, respectively.