ICALEPCS1991 - List of Authors (Nobusaka, H.)

Paper	Title	Page
S12FC09	Very Fast Feedback Control of Coil-Current in JT-60 Tokamak	442
	T. Aoyagi, Y. Matsuzaki, H. Nobusaka, M. Takahashi, T. Terakado, J. Yagyu JAEA/NAKA, Ibaraki-ken, Japan
	A direct digital control (DDC) system is adopted for controlling thyristor converters of power supplies in the JT-60 tokamak built in 1984. Microcomputers of the DDC were 5 MHz i8086 microprocessor and programs were written by assembler language and the processing time was under l ms. They were, however, too old in hardware and too complicated in software. New DDC system has been made in the JT-60 Upgrade (JT-60U) to control the power supplies more quickly under 0.25 and 0.5 ms of the processing time and also to write the programs used by high-level language. The new system consists of a host computer and five microcomputers with microprocessor on VMEbus system. The host computer AS3260 performs on-line processing such as setting the DDC under the discharge conditions and so on. Functions of the microcomputers with a 32-bit, 20 MHz microprocessor MC68030, whose OS are VxWorks and programs are written by C language, are real-time processing such as taking in instructions from a ZENKEI computer and in feedback control of currents and voltages of coils every 0.25 and 0.5 ms. The system is now operating very smoothly.
DOI •	reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S12FC09
About •	Received ※ 02 December 1991 — Accepted ※ 02 January 1992 — Issued ※ 04 December 1992
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Very Fast Feedback Control of Coil-Current in JT-60 Tokamak

442

T. Aoyagi, Y. Matsuzaki, H. Nobusaka, M. Takahashi, T. Terakado, J. Yagyu
JAEA/NAKA, Ibaraki-ken, Japan

A direct digital control (DDC) system is adopted for controlling thyristor converters of power supplies in the JT-60 tokamak built in 1984. Microcomputers of the DDC were 5 MHz i8086 microprocessor and programs were written by assembler language and the processing time was under l ms. They were, however, too old in hardware and too complicated in software. New DDC system has been made in the JT-60 Upgrade (JT-60U) to control the power supplies more quickly under 0.25 and 0.5 ms of the processing time and also to write the programs used by high-level language. The new system consists of a host computer and five microcomputers with microprocessor on VMEbus system. The host computer AS3260 performs on-line processing such as setting the DDC under the discharge conditions and so on. Functions of the microcomputers with a 32-bit, 20 MHz microprocessor MC68030, whose OS are VxWorks and programs are written by C language, are real-time processing such as taking in instructions from a ZENKEI computer and in feedback control of currents and voltages of coils every 0.25 and 0.5 ms. The system is now operating very smoothly.

DOI •

reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S12FC09

About •

Received ※ 02 December 1991 — Accepted ※ 02 January 1992 — Issued ※ 04 December 1992

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)