Hitachi, Ltd.

Hisanori Miyagaki

Hiroshi Matsumoto

Masahide Nomura

Akira Sugano

Tadayoshi Saito

Makoto Shimoda

Nobuo Kurihara

Yoshio Sato

Seiitsu Nigawara

Katsuhito Shimizu

Atsumi Watanabe

Mitsuyo Nishikawa

Tooru Kimura

Atsushi Takita

Toshihiko Higashi

Nobuyuki Yokokawa

Haruya Tobita

Yoshihiro Shimada

Atsushi Yokogawa

Susumu Takahashi

Yasuo Morooka

Hiroshi Yokoyama

Masayuki Fukai

Hiroshi Hanaoka

Akira Kaji

Keiji Oshima

Masayuki Kikuchi

Eiji Toyama

Sadao Yanada

Naganobu Honda

Hitoshi Yoshino

Kohji Tachibana

Eiji Tohyama

Masakazu Kondoh

Conflicting requests for cursor control of displaying are resolved by priority. The cursors can reflect attributes of their control or those of their control units, with visual attributes being color, shape or the like. Priority may be established between each cursor and a range of areas acceptable for cursor movement subdivided from the screen, or according to a priority of allowable functions, or according to a priority of conflicting operating times, or a combination of the same. Simultaneous control of a plurality of cursors can be permitted when there is no conflict.

Method and apparatus for screen displaying

A method for controlling a controlled system by a controller such that a controlled variable can be brought into conformity with a desired value. With respect to at least one of input/output variables for a combined controlling-controlled system, which includes in combination the controller and the controlled system, and input/output variables for the controlled system, information containing its characteristics is taken out from the combined controlling-controlled system. The information with the characteristics contained therein is inputted to a neural network which has been caused beforehand to learn a correlation between the information containing the characteristics and control parameters. From the neural network, one or more of the control parameters, said one or more control parameters corresponding to a corresponding number of inputs to the neural network, are outputted to the controller.

Process control method and system for performing control of a controlled

A process control system controls a large scale plant such as thermal power plant. This process control system includes a target setting unit for setting an operation target, a control unit for receiving a signal indicating the operation target and for outputting a controlled variable to operate the process, an evaluation unit for quantitatively evaluating operation characteristics corresponding to the operation target of the process operated on the basis of a signal indicating the controlled variable supplied from the control unit, a modification unit for extracting an optimum operation process qualitatively squaring or conforming with the evaluated value derived by the evaluation unit out of a modification rule predetermining operation unit in qualitative relation between the operation characteristics and the operation target of the process and for determining the modification rate of the control unit, a storage unit having a model of a neural network for storing a relation between the operation target and the modification rate derived by the modification unit as a connection state within a circuit, and a learning unit for making the model of the neural network learn the relation between the operation target and the modification rate.

Process control system and power plant process control system

A process controller having a setting section for giving a target value for a fixed period of time, a control section including a predicting section for predicting a process response for the fixed time period in accordance with a current value of a process control amount and a virtual value of an operation amount; a quantitating section for quantitating a difference between the target value and the result by the predicting section; a calculating section for calculating a basic signal of the operation amount in accordance with the quantitated result, and an optimizing section including a predicting section for predicting a process response for the fixed time period with a control amount and an initial operation amount of the process; another quantitating section for quantitating a difference between the prediction and the target value, a calculating section for calculating the operation amount in accordance with the second quantitated result; and a section for performing control in such a way that the quantitating result and a predetermined evaluation criterion are compared with each other to perform an evaluation. The calculated result of the operation amount is repeatedly applied to the predicting section until the evaluation criterion is satisfied, a correcting signal used for optimizing the operation amount is obtained from a value of the operation amount when the quantitated result satisfies the criterion, and the correcting signal is added to a basic signal of the control section, and the adding result is output to the process.

Process controller for controlling a process to a target state

A process control apparatus and a process control system for observing the waveform of the deviation between a set point which controls the process in a control loop and the process controlled variable transmitted from the process so that the operating parameters are adjusted in accordance with a predetermined adjustment rule by using the deviation based upon the absolute value of a wave for every half cycle of the wave. Therefore, even if the process controlled variable is influenced, the area of the wave cannot be changed significantly. As a result, the operating parameters can be adjusted correctly, causing the process controlled variable to quickly coincide with the set point.

Process control apparatus and method for adjustment of operating

A system and a method of monitoring and displaying in which control screen indicating a control data of a control device for process control displayed on the display screen of a display unit by a touch operation on a diagram of the control device, the control data being further selected by another touch operation. The display condition of the control data display area thus changes, the operator being permitted to visually check whether the operation has been selected correctly. After visual confirmation, a switch disposed outside of the display screen and corresponding to the called control screen is operated to start the operation of the control device determined for control for the first time at this time point. In case of a combined display of a control device and a control screen, on the other hand, a first display unit is utilized such that the called control screen is displayed at a position far from the control device to be controlled, thereby not hiding the control device display. The control screen may be moved to a given position on the system diagram. A second display unit is utilized such that the original system diagram is displayed in a reduced form in combination with and not superimposed on the called control screen. The control screen and the control-related screen are called repeatedly so that when the reduction rate of the original system diagram exceeds a critical value, the reduction rate is fixed to a predetermined value and the control screens are displayed in scroll.

Process monitoring and control system and method of process monitoring

A combustion control method wherein manipulated variables or the amounts of fuel and air in at least one combustion zone of a boiler are regulated so that both the amount of nitrogen oxides and the amount of unburned coal in the ash at an outlet of a burner furnace or at least one of them passes the regulation standards and satisfies the requirements for operating a plant. The method is characterized by varying the amounts of fuel and air in performing trial operations on manipulated variables to evaluate the nitrogen oxides at the furnace outlet, the unburned coal in the ash at the furnace outlet and the stability of combustion, and declaring as optimum manipulated variables those amounts of fuel and air used for performing the trial operations which achieve results such that the combustion is found to be stabilized, at least the nitrogen oxides at the furnace outlet satisfy the requirement and the thermal efficiency of the boiler is judged to be at the highest level by a boiler thermal efficiency judging section.

Combustion control method

This invention relates to the supervision of a combustion state of a combustion furnace. A flame formed concentrically with the direction of a fuel jetted from a burner being the center is measured from its side, and two oxidizing flame zones as high luminance zones are extracted. Using the shape parameters of the flame, an index for reducing NOx and unburnt components in ash are calculated and estimated so as to supervise the combustion state. The positions or centroids of the flames and the distance between the centroids are used as the shape parameters, and the flame shape is divided into two zones for easy display of each zone.

Method and apparatus for supervising combustion state

A method of controlling the operation of a thermoelectric power generating plant, in which the operation of the steam generating equipment and the turbine is controlled in accordance with the plant operation parameters obtained from given patterns of start up and operation of the plant. The method comprises: temporarily setting, in accordance with the above-mentioned patterns, the plant operation parameters concerning the rates of change of state of the plant such as the rates of turbine acceleration and turbine load and rates of increase of the main steam temperature and pressure; estimating the change of the quantity of state of main steam at a designated future moment; estimating the thermal stresses in respective stress-evaluation portions of the boiler and turbine; comparing the estimated thermal stresses with respective allowable thermal stresses determined so as to correspond to the consumption of the life allowed for each start up and operation cycle of the plant; selecting one of the estimated thermal stresses which has smaller margin to the allowable thermal stress and obtaining the operation parameter which provided the maximum rate of change of the state of the plant; repeating these steps until the command state is attained; and controlling the boiler and the turbine in accordance with the thus obtained plant operation parameter.

Method of controlling operation of thermoelectric power station

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Hitachiota, Japan

Hisanori Miyagaki