Hitachi, Ltd.

Tooru Kimura

Satoru Shimizu

Yoshio Maruyama

Katsuhito Shimizu

Yoshiharu Hayashi

Yasushi Hayasaka

Hidekazu Fujimura

Akira Sugano

Masao Furukawa

Hisanori Miyagaki

Atsushi Takita

Haruya Tobita

Yukiko Mouri

Hiroshi Matsumoto

Masayuki Fukai

Masahide Nomura

Mitsuyo Nishikawa

Masayuki Kikuchi

Akira Fukuhara

Eiji Toyama

An objective is to quickly provide appropriate maintenance services at low costs during routine inspection procedures and/or upon occurrence of abnormal events at thermal power plants or stations. In a thermal power plant maintenance system comprising a control devicefor control of operation conditions and process amounts of plant equipment and a maintenance tooloperatively linked to the control devicevia a networkfor performing maintenance of a controlling controlleras built in the control device, the system further comprises a remote maintenance devicethat executes similar functions to those offered by the maintenance toolfor bidirectionally transferring plant data along with data concerning the controlling controller's status via a communications linebetween the maintenance tooland the remote maintenance deviceto thereby provide maintenance services of the thermal power plant of interest.

Method for providing power plant maintenance services

Documents used for process control can be managed and maintained from a document server and a terminal. In order to update the documents quickly so that an operated process is always kept in the most preferable state of operation, the document server stores and manages production documents used for actually controlling and monitoring a control system plant, whereas the terminal system is used to refer and edit plant documents. The terminal can synchronize contents of the plant documents in the document server with those in the control system before storing the synchronized plant documents in the terminal.

System and method for document management and synchronization

Document management system and method

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 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 monitor method for the combustion conditions in a furnace of a boiler having a plurality of burners is disclosed. The method includes the steps of detecting the flame intensity at a predetermined position of a flame, by using an optical fiber having as its view the predetermined position at the flame of each of the plurality of burners; judging if the combustion conditions of each burner are normal or not, based on if the flame intensity detected for each burner flame is within a predetermined normal level range; and displaying the judgement results. Preferably, an image fiber for obtaining a flame image indicating the combustion conditions is provided for at least one of the burners, and the normal level range is determined based on the flame image obtained by the image fiber.

Combustion monitor method for multi-burner boiler

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Hitachi, Japan

Tooru Kimura