ICALEPCS1991 - List of Authors (Takahashi, M.)

Paper	Title	Page
S12FC08	Development of a VME Multi-Processor System for Plasma Control at the JT-60 Upgrade	438
	M. Takahashi, H. Akasaka, Y. Kawamata, T. Kimura, K. Kurihara JAEA/NAKA, Ibaraki-ken, Japan
	Design and initial operation results are reported of a VME multi-processor system for plasma control at a large fusion device named "the JT-60 Upgrade" utilizing three 32-bit MC88100 based RISC computers and VME components. Development of the system was stimulated by faster and more accurate computation requirements for the plasma position and current control. The RISC computers operate at 25 MHz along with two cache memories named MC88200. We newly developed VME bus modules of up/down counter, analog-to-digital converter and clock pulse generator for measuring magnetic field and coil current and for synchronizing the processing in the three RISCs and direct digital controllers (DDCs) of magnet power supplies. We also evaluated that the speed of the data transfer between the VME bus system and the DDCs through CAMAC highways satisfies the above requirements. In the initial operation of the JT-60 upgrade, it has been proved that the VME multi-processor system well controls the plasma position and current with a sampling period of 250 ¿sec and a delay of 500 ¿sec.
DOI •	reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S12FC08
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)

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

Development of a VME Multi-Processor System for Plasma Control at the JT-60 Upgrade

438

M. Takahashi, H. Akasaka, Y. Kawamata, T. Kimura, K. Kurihara
JAEA/NAKA, Ibaraki-ken, Japan

Design and initial operation results are reported of a VME multi-processor system for plasma control at a large fusion device named "the JT-60 Upgrade" utilizing three 32-bit MC88100 based RISC computers and VME components. Development of the system was stimulated by faster and more accurate computation requirements for the plasma position and current control. The RISC computers operate at 25 MHz along with two cache memories named MC88200. We newly developed VME bus modules of up/down counter, analog-to-digital converter and clock pulse generator for measuring magnetic field and coil current and for synchronizing the processing in the three RISCs and direct digital controllers (DDCs) of magnet power supplies. We also evaluated that the speed of the data transfer between the VME bus system and the DDCs through CAMAC highways satisfies the above requirements. In the initial operation of the JT-60 upgrade, it has been proved that the VME multi-processor system well controls the plasma position and current with a sampling period of 250 ¿sec and a delay of 500 ¿sec.

DOI •

reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S12FC08

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)

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)