Yokogawa Electric Corporation

Nec Corporation

Hideharu Yajima

Yoshinori Kobayashi

Hiroaki Nakajima

Hiroyuki Takizawa

Satoshi Kitamura

Kenji Habaguchi

Kuniharu Akabane

Kazushi Sakamoto

Kiyotaka Kozakai

Senji Watanabe

Masafumi Kisa

Mitsuhiro Kurono

Takeshi Hongo

Kazuyuki Ito

Hiroshi Tachikawa

Yuuzou Hasegawa

A controller is a controller forming, with another controller, a redundant controller. The controller includes a communication function unit that performs communication with an external device capable of executing control calculation needed for process control for a plant, and a redundancy management unit that switches states of the controller between an active state where a result of the control calculation obtained from the external device via the communication function unit is reflected in the process control and a standby state where the result of the control calculation is not reflected in the process control. The redundancy management unit switches the states of the controller to bring one of the controller and the another controller into the active state.

Controller and control method

A parameter copying method is applied to a duplex system in which MPU and a main memory are duplicated and duplex operations on a hot standby system are performed. The parameter copying method includes cache reading data in the main memory corresponding to one MPU, cache writing the data read in the cache reading step on an as-is basis, and writing the data into the main memory corresponding to the one MPU by a block write that is produced by a cache replace caused due to the cache writing step, and also writing the same data into the main memory corresponding to the other MPU by the block write on a basis of a mirrored write.

Parameter copying method and parameter copying device

There is provided a distributed control system including a plurality of field controllers which are connected through a control network. Each of the field controllers includes: a control clock that defines a control timing of the field controller; and an adjustment unit that adjusts a control time of the control clock depending on a network time obtained through the control network.

Distributed control system

The field control system includes: a field device; a field controller which is connected to a control network and which executes a computation processing for controlling the field device according to a given control cycle while executing a data communication between the field controller and the field device, the field controller including a communication unit configured to execute the data communication with the field device, and a control computation unit configured to execute the computation processing independently from the communication unit; and an operation monitor which is connected to the control network and which operates and monitors the field device, the operation monitor including a network clock which provides a common network time to the control network. The control computation unit and the communication unit execute the computation processing and the data communication in synchronism with each other in accordance with a timer clock based on the network time.

Field control system

There is provided a duplexed field controller. The duplexed field controller includes: first and second control units between which a control authority is switchable; a first application clock that is updated based on a reference clock so as to define a timing of an application operation of the first control unit; a second application clock that is updated based on the reference clock so as to define a timing of an application operation of the second control unit; and an update control unit that bypasses the first update of the second application clock after switching of the control authority, if the first application clock is ahead of the second application clock when the control authority is switched from the first control unit to the second control unit.

Duplexed field controller

A parallel operation power supply control system has a plurality of switching power supply modules for supplying electric power in parallel to a logic device, and a parallel operation power supply control module connected to a superior controller for control of the plurality of the switching power supply modules. Each of the plurality of the switching power supply modules comprises a DC-DC converter, a drive pulse generator for driving the DC-DC converter, and an electric current feedback unit for detecting an electric current outputted from the DC-DC converter and for feeding the detected result in the form of a first data to the parallel operation power supply control module. The parallel operation power supply control module comprises an arithmetic processor for arithmetically processing the first data fed from the plurality of the switching power supply modules to produce corresponding second data, a plurality of error amplifiers for producing error data according to the second data and a voltage inputted into the logic device and for outputting the error data to each drive pulse generator, and a basic pulse generator for outputting basic pulses to each drive pulse generator.

Parallel operation power supply control system

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Tokyo, Japan

Hideharu Yajima