Tullio Bonicelli - Academia.edu (original) (raw)

Papers by Tullio Bonicelli

AIP Conference Proceedings, 2018

In June 2018 the SPIDER device, which is the full-size prototype of the negative ion source and e... more In June 2018 the SPIDER device, which is the full-size prototype of the negative ion source and extractor for the ITER Heating Neutral Beam has entered the first operation phase at the Neutral Beam Test Facility (NBTF) in Padova, Italy. This paper describes the present status of the device, the experimental plans and the results obtained during the first experimental campaign of the radio-frequency driven plasma source.

Fusion Technology 1992, 1993

A fast power amplifier has been designed and built to control the plasma vertical position even w... more A fast power amplifier has been designed and built to control the plasma vertical position even with the more demanding configurations that will be produced in JET in the future. Switched inverters with gate turn-off thyristors, allow a fast response time (200 μs) to be reached at high performance (10 kV, 2.5 kA); a new concept of control, based on a multilevel hysteresis cycle improves the performance compared with pulse width modulation. The equipment has been designed and built; factory tests are in progress.

IEE Colloquium on Power Electronics for Demanding Applications, 1999

The author briefly describes the background to the JET (Joint European Torus) nuclear fusion proj... more The author briefly describes the background to the JET (Joint European Torus) nuclear fusion project, and then describes the JET pulsed loads and the distribution system. The pulsed loads can be subdivided in three categories: toroidal and poloidal magnets, whose power supplies are described in this paper, neutral beam injectors and RF antennas. The execution of a typical JET pulse requires a peak power in excess of 1000 MW. The power supply system is directly connected to the National Grid via three 400 kV/36 kV transformers. There are also tow identical flywheel generators connected to the toroidal coils and solenoid. The author described the thyristor converters used for JET. The JET fast power supplies are also described.

2005 European Conference on Power Electronics and Applications, 2005

A 170 GHz, 2 MW, steady state gyrotron is being developed in a collaboration between European res... more A 170 GHz, 2 MW, steady state gyrotron is being developed in a collaboration between European research associations and industries to be used for the electron cyclotron resonance heating (ECRH) system of ITER, the next step in nuclear fusion research. The gyrotron is presently in the prototype state. For the test facility dedicated to the testing of this gyrotron, new power supplies need to be procured. A feasibility study was performed aimed at using new designs based on present day techniques and at performing and constructing a prototype for further testing and evaluation. The prototype BPS (body power supply) which is connected to the body of the gyrotron is now in an advanced stage of construction and the first test results are in close agreement with the design objectives of the feasibility study

EPJ Web of Conferences, 2019

The EU gyrotron for the ITER Electron Cyclotron (EC) heating system has been developed in coordin... more The EU gyrotron for the ITER Electron Cyclotron (EC) heating system has been developed in coordinated efforts of the EGYC Consortium, Thales ED (TED) and Fusion for Energy (F4E) and under the supervision of ITER Organization Central Team. After the successful verification of the design of the 1MW, 170 GHz hollow cylindrical cavity gyrotron operating at the nominal TE32,9 mode with a short pulse gyrotron prototype at KIT, an industrial CW gyrotron prototype was manufactured by TED and tested at ~0.8 MW output power and 180 s pulse duration, which is the limit of the HV power supply currently available at KIT. The experiments are being continued at SPC in 2018 to extend further the pulse duration, taking advantage of the existing CW full-power capabilities of the gyrotron test facility recently upgraded for the FALCON project. The gyrotron cavity interaction is very sensitive to the alignment of the internal mechanical parts of the gyrotron tube with the magnetic field generated by th...

Proceedings. 12th Symposium on Fusion Engineering, 1987, Vol.2, 1987

The activities towards the establishment of the NB Test Facility (NBTF) in Padua-Italy and those ... more The activities towards the establishment of the NB Test Facility (NBTF) in Padua-Italy and those related to the procurement of the heating neutral beams for ITER have recently reached a good level of progress thanks to the finalization of the agreements on the NBTF between F4E (the EU Domestic Agency for ITER), Consorzio RFX (the host of the NB test facility) and the ITER organization. This paper presents the status of the design of the various components within the EU scope of procurement, with a focus on the modifications implemented in the last years as a result of intense R&D activity undertaken in EU.

Electron Cyclotron Emission and Electron Cyclotron Resonance Heating (EC-16), 2011

2013 IEEE 14th International Vacuum Electronics Conference (IVEC), 2013

ABSTRACT EU is developing a 1 MW cylindrical cavity gyrotron. In the last year the design of the ... more ABSTRACT EU is developing a 1 MW cylindrical cavity gyrotron. In the last year the design of the components of the new gyrotron has been finalized while the technological design of the new tube has been defined. In the present paper, the main characteristics of the new EU gyrotron for ITER are presented.

Fusion Engineering and Design, 2009

The electron cyclotron (EC), ion cyclotron (IC), heating-neutral beam (H-NB) and, although not in... more The electron cyclotron (EC), ion cyclotron (IC), heating-neutral beam (H-NB) and, although not in the day 1 baseline, lower hybrid (LH) systems intended for ITER have been reviewed in 2007/2008 in light of progress of physics and technology in the field. Although the overall specifications are unchanged, notable changes have been approved. Firstly, it has been emphasized that the H&CD systems are vital for the ITER programme. Consequently, the full 73 MW should be commissioned and available on a routine basis before the D/T phase. Secondly, significant changes have been approved at system level, most notably: the possibility to operate the heating beams at full power during the hydrogen phase requiring new shine through protection; the possibility to operate IC with 2 antennas with increased robustness (no moving parts); the possible increase to 2 MW of key components of the EC transmission systems in order to provide an easier upgrading of the EC power as may be required by the project; the addition of a building dedicated to the RF power sources and to a testing facility for acceptance of diagnostics and heating port plugs. Thirdly, the need of a plan for developing, in time for the active phase, a CD system such as LH suitable for very long pulse operation of ITER was recognised. The review describes these changes and their rationale.

Fusion Engineering and Design, 2001

JET has available one of the world's most powerful AC/DC multi-convertor systems, with unique cap... more JET has available one of the world's most powerful AC/DC multi-convertor systems, with unique capabilities in terms of delivery of high DC voltages and currents. Whilst the primary purpose of the system is the supply of the loads required for the experimental sessions, there is scope for other uses, in particular for testing of high power electrical equipment. The first successful example of the utilization of these capabilities was achieved with the establishment of a new Test Cell powered by the Toroidal Flywheel Generator Convertor (TFGC). The new facility was used for the test of a prototype Bypass switch manufactured within the ITER programme. The aim was to prove the switch is able to fulfil the requirements concerning contact life and general reliability of the assembly.

The paper describes the international effort to develop the negative neutral beam injectors for I... more The paper describes the international effort to develop the negative neutral beam injectors for ITER with the construction of a test facility where two testbeds will be installed. The first testbed is a ITER full size negative ion source where the necessary ion current density has to be produced and it will also support the development of the diagnostic neutral beam injector to be installed in ITER. The second testbed is the prototype of the ITER heating neutral beam injector.

Fusion Science and Technology, 2008

The ITER electron cyclotron heating (ECH) baseline scheme (2001) is composed of 24 gyrotrons, eac... more The ITER electron cyclotron heating (ECH) baseline scheme (2001) is composed of 24 gyrotrons, each generating 1 MW of radio-frequency power at 170 GHz in addition to 3 gyrotrons (1 MW) at 120 GHz for breakdown assist. Considering an efficiency of Ն45%, which can be achieved with the depressed-collector-type gyrotron (CPD), the amount of electrical power would be in the range of 55 MW. This paper has two purposes. First, it presents requirements that will be imposed on the electrical power supplies with regard to the updated physics needs for ITER presently being discussed. Demanding parameters (like modulation capability, transient margin, and fault clearing) will be described. In this context, the consequences of those new requirements on the technical choices and the impact on the complexity of the power supplies will be discussed. Second, two possible schemes for the ITER reference power supply design for the ECH system will be compared. The advantages (and respective disadvantages) of each solution will be highlighted taking care of the requirements previously presented. In conclusion, a proposal is presented for a revised ECH power supply structure.

Plasma Devices and Operations, 1998

ABSTRACT This paper focuses on the recent modifications of the Coil Power Supply and Distribution... more ABSTRACT This paper focuses on the recent modifications of the Coil Power Supply and Distribution System (CPSDS) to adapt it to the revised magnet configuration and plasma scenarios. Updated performance of the main components (AC/DC converters, switching networks and discharge circuits) are presented. The layout of the equipment is described with emphasis on the revision made to meet the new seismic requirements and to reduce the cost of busbars.

Fusion Engineering and Design, 2009

The Electron Cyclotron system for ITER is an in-kind procurement shared between five parties and ... more The Electron Cyclotron system for ITER is an in-kind procurement shared between five parties and the total installed power will be 24 MW, corresponding to a nominal injected power of 20 MW to the plasma, with a possible upgrade up to 48 MW (corresponding to 40 MW injected). Some critical issues have been raised and changes are proposed to simplify these procurements and to facilitate the integration into ITER. The progress in the design and the integration of the EC system into the whole project is presented in this paper, as well as some issues still under studies and some recommendations made by external expert committees.

AIP Conference Proceedings, 2018

In June 2018 the SPIDER device, which is the full-size prototype of the negative ion source and e... more In June 2018 the SPIDER device, which is the full-size prototype of the negative ion source and extractor for the ITER Heating Neutral Beam has entered the first operation phase at the Neutral Beam Test Facility (NBTF) in Padova, Italy. This paper describes the present status of the device, the experimental plans and the results obtained during the first experimental campaign of the radio-frequency driven plasma source.

Fusion Technology 1992, 1993

A fast power amplifier has been designed and built to control the plasma vertical position even w... more A fast power amplifier has been designed and built to control the plasma vertical position even with the more demanding configurations that will be produced in JET in the future. Switched inverters with gate turn-off thyristors, allow a fast response time (200 μs) to be reached at high performance (10 kV, 2.5 kA); a new concept of control, based on a multilevel hysteresis cycle improves the performance compared with pulse width modulation. The equipment has been designed and built; factory tests are in progress.

IEE Colloquium on Power Electronics for Demanding Applications, 1999

The author briefly describes the background to the JET (Joint European Torus) nuclear fusion proj... more The author briefly describes the background to the JET (Joint European Torus) nuclear fusion project, and then describes the JET pulsed loads and the distribution system. The pulsed loads can be subdivided in three categories: toroidal and poloidal magnets, whose power supplies are described in this paper, neutral beam injectors and RF antennas. The execution of a typical JET pulse requires a peak power in excess of 1000 MW. The power supply system is directly connected to the National Grid via three 400 kV/36 kV transformers. There are also tow identical flywheel generators connected to the toroidal coils and solenoid. The author described the thyristor converters used for JET. The JET fast power supplies are also described.

2005 European Conference on Power Electronics and Applications, 2005

A 170 GHz, 2 MW, steady state gyrotron is being developed in a collaboration between European res... more A 170 GHz, 2 MW, steady state gyrotron is being developed in a collaboration between European research associations and industries to be used for the electron cyclotron resonance heating (ECRH) system of ITER, the next step in nuclear fusion research. The gyrotron is presently in the prototype state. For the test facility dedicated to the testing of this gyrotron, new power supplies need to be procured. A feasibility study was performed aimed at using new designs based on present day techniques and at performing and constructing a prototype for further testing and evaluation. The prototype BPS (body power supply) which is connected to the body of the gyrotron is now in an advanced stage of construction and the first test results are in close agreement with the design objectives of the feasibility study

EPJ Web of Conferences, 2019

The EU gyrotron for the ITER Electron Cyclotron (EC) heating system has been developed in coordin... more The EU gyrotron for the ITER Electron Cyclotron (EC) heating system has been developed in coordinated efforts of the EGYC Consortium, Thales ED (TED) and Fusion for Energy (F4E) and under the supervision of ITER Organization Central Team. After the successful verification of the design of the 1MW, 170 GHz hollow cylindrical cavity gyrotron operating at the nominal TE32,9 mode with a short pulse gyrotron prototype at KIT, an industrial CW gyrotron prototype was manufactured by TED and tested at ~0.8 MW output power and 180 s pulse duration, which is the limit of the HV power supply currently available at KIT. The experiments are being continued at SPC in 2018 to extend further the pulse duration, taking advantage of the existing CW full-power capabilities of the gyrotron test facility recently upgraded for the FALCON project. The gyrotron cavity interaction is very sensitive to the alignment of the internal mechanical parts of the gyrotron tube with the magnetic field generated by th...

Proceedings. 12th Symposium on Fusion Engineering, 1987, Vol.2, 1987

The activities towards the establishment of the NB Test Facility (NBTF) in Padua-Italy and those ... more The activities towards the establishment of the NB Test Facility (NBTF) in Padua-Italy and those related to the procurement of the heating neutral beams for ITER have recently reached a good level of progress thanks to the finalization of the agreements on the NBTF between F4E (the EU Domestic Agency for ITER), Consorzio RFX (the host of the NB test facility) and the ITER organization. This paper presents the status of the design of the various components within the EU scope of procurement, with a focus on the modifications implemented in the last years as a result of intense R&D activity undertaken in EU.

Electron Cyclotron Emission and Electron Cyclotron Resonance Heating (EC-16), 2011

2013 IEEE 14th International Vacuum Electronics Conference (IVEC), 2013

ABSTRACT EU is developing a 1 MW cylindrical cavity gyrotron. In the last year the design of the ... more ABSTRACT EU is developing a 1 MW cylindrical cavity gyrotron. In the last year the design of the components of the new gyrotron has been finalized while the technological design of the new tube has been defined. In the present paper, the main characteristics of the new EU gyrotron for ITER are presented.

Fusion Engineering and Design, 2009

The electron cyclotron (EC), ion cyclotron (IC), heating-neutral beam (H-NB) and, although not in... more The electron cyclotron (EC), ion cyclotron (IC), heating-neutral beam (H-NB) and, although not in the day 1 baseline, lower hybrid (LH) systems intended for ITER have been reviewed in 2007/2008 in light of progress of physics and technology in the field. Although the overall specifications are unchanged, notable changes have been approved. Firstly, it has been emphasized that the H&CD systems are vital for the ITER programme. Consequently, the full 73 MW should be commissioned and available on a routine basis before the D/T phase. Secondly, significant changes have been approved at system level, most notably: the possibility to operate the heating beams at full power during the hydrogen phase requiring new shine through protection; the possibility to operate IC with 2 antennas with increased robustness (no moving parts); the possible increase to 2 MW of key components of the EC transmission systems in order to provide an easier upgrading of the EC power as may be required by the project; the addition of a building dedicated to the RF power sources and to a testing facility for acceptance of diagnostics and heating port plugs. Thirdly, the need of a plan for developing, in time for the active phase, a CD system such as LH suitable for very long pulse operation of ITER was recognised. The review describes these changes and their rationale.

Fusion Engineering and Design, 2001

JET has available one of the world's most powerful AC/DC multi-convertor systems, with unique cap... more JET has available one of the world's most powerful AC/DC multi-convertor systems, with unique capabilities in terms of delivery of high DC voltages and currents. Whilst the primary purpose of the system is the supply of the loads required for the experimental sessions, there is scope for other uses, in particular for testing of high power electrical equipment. The first successful example of the utilization of these capabilities was achieved with the establishment of a new Test Cell powered by the Toroidal Flywheel Generator Convertor (TFGC). The new facility was used for the test of a prototype Bypass switch manufactured within the ITER programme. The aim was to prove the switch is able to fulfil the requirements concerning contact life and general reliability of the assembly.

The paper describes the international effort to develop the negative neutral beam injectors for I... more The paper describes the international effort to develop the negative neutral beam injectors for ITER with the construction of a test facility where two testbeds will be installed. The first testbed is a ITER full size negative ion source where the necessary ion current density has to be produced and it will also support the development of the diagnostic neutral beam injector to be installed in ITER. The second testbed is the prototype of the ITER heating neutral beam injector.

Fusion Science and Technology, 2008

The ITER electron cyclotron heating (ECH) baseline scheme (2001) is composed of 24 gyrotrons, eac... more The ITER electron cyclotron heating (ECH) baseline scheme (2001) is composed of 24 gyrotrons, each generating 1 MW of radio-frequency power at 170 GHz in addition to 3 gyrotrons (1 MW) at 120 GHz for breakdown assist. Considering an efficiency of Ն45%, which can be achieved with the depressed-collector-type gyrotron (CPD), the amount of electrical power would be in the range of 55 MW. This paper has two purposes. First, it presents requirements that will be imposed on the electrical power supplies with regard to the updated physics needs for ITER presently being discussed. Demanding parameters (like modulation capability, transient margin, and fault clearing) will be described. In this context, the consequences of those new requirements on the technical choices and the impact on the complexity of the power supplies will be discussed. Second, two possible schemes for the ITER reference power supply design for the ECH system will be compared. The advantages (and respective disadvantages) of each solution will be highlighted taking care of the requirements previously presented. In conclusion, a proposal is presented for a revised ECH power supply structure.

Plasma Devices and Operations, 1998

ABSTRACT This paper focuses on the recent modifications of the Coil Power Supply and Distribution... more ABSTRACT This paper focuses on the recent modifications of the Coil Power Supply and Distribution System (CPSDS) to adapt it to the revised magnet configuration and plasma scenarios. Updated performance of the main components (AC/DC converters, switching networks and discharge circuits) are presented. The layout of the equipment is described with emphasis on the revision made to meet the new seismic requirements and to reduce the cost of busbars.

Fusion Engineering and Design, 2009

The Electron Cyclotron system for ITER is an in-kind procurement shared between five parties and ... more The Electron Cyclotron system for ITER is an in-kind procurement shared between five parties and the total installed power will be 24 MW, corresponding to a nominal injected power of 20 MW to the plasma, with a possible upgrade up to 48 MW (corresponding to 40 MW injected). Some critical issues have been raised and changes are proposed to simplify these procurements and to facilitate the integration into ITER. The progress in the design and the integration of the EC system into the whole project is presented in this paper, as well as some issues still under studies and some recommendations made by external expert committees.