- Email: [email protected]
Design of a new P-NBI control system for 100-s injection in JT-60SA
Available online at www.sciencedirect.com
Fusion Engineering and Design 83 (2008) 280–282
Design of a new P-NBI control system for 100-s injection in JT-60SA F. Okano a,∗ , S. Shinozaki a , A. Honda a , K. Ooshima a , S. Numazawa b , Y. Ikeda a a
Fusion Research and Development Directorate, Japan Atomic Energy Agency, Naka, Ibaraki-ken 311-0193, Japan b Streem Corporation, Hitachinaka, Ibaraki-ken 312-0062, Japan Available online 4 January 2008
Abstract Modification of JT-60U to a superconducting device (so-called JT-60SA) has been planned to contribute to ITER and DEMO. The positiveion-based NBI system (P-NBI) is required to inject 24 MW for 100 s with 12 units. The P-NBI control system is to be fully remodeled with PLC (Programmable Logic Controller), which is featured by high market availability, system extensibility, cost-effectiveness, and independent development in programming. One of the critical issues to apply the PLC to the P-NBI control system is to control quickly the high voltage power supplies within 200 s. For this purpose, the fastest PLC dealing with 4 refresh words at the processing time of 200 s is to be employed. The second issue is to construct a data acquisition system for such a large number of data channels (∼2300 digital and ∼1300 analog data channels). The use of PLC linked with PC-based data measurement devices via Ethernet allows processing the large number of channels. The third issue is to make the man–machine interface simple. The marketed software giving an easy product of graphic menus is available for PLC programming. From these results, it is expected that commercial PLC could be applied to the large-scale control system of the P-NBI system for 100 s operations. © 2007 Elsevier B.V. All rights reserved. Keywords: JT-60SA; Positive-ion-based NBI system; PLC; 100 s operations
1. Introduction The modification of the JT-60U to a fully superconducting coil tokamak, JT-60SA (Super Advanced), has been planned as the satellite device for the ITER (International Thermonuclear Experimental Reactor) [1]. The positive-ion-based NBI system (P-NBI), which will be the main heating system on JT-60SA, is required to extend its pulse duration from 30 to 100 s at the total injection power of 24 MW with 12 units [2]. To achieve this requirement of 100 s operation, the P-NBI heating system requires modification of the control system in addition to the power supply system. The P-NBI control system is to operate high power beams under communication with the JT-60 central control system [3]. Since the P-NBI control system was constructed more than 20 years ago, the system components such as local control panels are too old to reuse for the JT-60SA. Moreover, the present system employs the central control system to operate 12 units, which has a close relationship between units. This type of system relies totally on the reliability of every unit. Should there be a failure of some unit, the entire system is often down. To obtain a high reliable control sys-
∗
Corresponding author. Tel.: +81 29 2707433; fax: +81 29 2707449. E-mail address: [email protected] (F. Okano).
0920-3796/$ – see front matter © 2007 Elsevier B.V. All rights reserved. doi:10.1016/j.fusengdes.2007.11.014
tem, we intend to design a new control system for the JT-60SA P-NBI system. The design is based on a distributed control system using the modern PLC. The relationship between units is to be reduced as much as possible. This allows simplification of the control system and to allows straightforward expansibility of the multi-unit control system. Furthermore, the new system is intended to be constructed by the user itself, without the need for a custom-made program written by a software developer. 2. Design concept for P-NBI control system 2.1. Present system Fig. 1 shows the present P-NBI control system. The CP1 is composed of the earliest PLC and a TDG (Timing Distribution Generator) to distribute the beam-on timing to the CP2 of each unit. The CP2 is a fast controller to turn on/off the beam current in response to the CP1’s command. The TSC (Timing Sequence Controller) in the CP2 gives the timing to all components, such as gas injection, filament, arc, deceleration, acceleration, deflection coil, canceling coil, and fast shutter. It also turns off the beam current to protect the high voltage components (ion source) against breakdowns. In the CP1 and CP2, these functions are produced by customized circuit boards with memory IC.
F. Okano et al. / Fusion Engineering and Design 83 (2008) 280–282
281
Fig. 1. Present P-NBI control system.
Fig. 2. Designed control system for JT-60SA.
The workstations (W/S) were introduced to manage multiunits operation, to handle a large amount of data, and to communicate with the JT-60 central control computer. Each unit can be operated independently as far as the interface between the workstations and others units is not interrupted.
unit as shown in Table 1. A customized IC chip in the CP2 controls the acceleration power supply. In our survey of the PLC technical progress, one of the fastest PLCs, made by Yokogawa Electric Corporation, can deal with 4 refresh words (1 word: 16 I/O) in a processing time of 200 s so long as the programming steps are less than 2.8 K. Thus, the PLC can communicate 16 data with 4 I/O units, which satisfies the fast controllability requirement for the high voltage power supply. For other commands to the sub-systems for gas injection, filament, etc., the time response is to be less than 100 ms where normal PLCs are available. The PLC has a remote-control function with a fiber-optic communication system, the so-called FA-Bus. This function allows controlling the local control panels (I/O units) ∼200 m away from the central control room without specific communication setup. The transmission speed is 10 Mbps so that we do not worry about the I/O refresh time and in ladder programming. The PLC network is FL-net to provide intercommunication between different type of PLCs, such as the fastest PLC and normal PLCs. The FL-net is the open controller level network which is the result of a standardization initiative of JEMA (Japan Electrical Manufactures Association). There are 12 P-NBI units, each of which is to be independently controlled. In the case of plasma injection, it is necessary to synchronize the injection timing with other units. The timing of beam injection is delivered to each unit from the JT-60 central control system via the hardware, without a softwareinduced time delay. This simple interface enhances the reliability of unit operation even though other units are down. This structure
2.2. Design requirements The key issue for the new control system is to keep high reliability, expandability, and continuity with the functions of the present control system. To realize such a control system, the design concept was decided as follows: (a) The control system should be composed of commercially marketed components, which are well supported by manufacturing company in order to easily obtain replacement parts. (b) The control system is to be a distributed control system for each unit, which allows operating each unit independently. (c) The control system should be simplified as much as possible to ensure high reliability. (d) The other important key was to construct the control system by the user itself to reduce the cost of constructing a new system. 3. PLC-based control system The modern PLC is an attractive control device to construct the P-NBI control system. Fig. 2 shows the designed PLC-based P-NBI control system. There are three keys to apply the PLC to the P-NBI control system. 3.1. Fast controllability In the present control system, the GTO (Gate turn-off thyristor) switch in the high voltage power supply should be turned on/off within 200 s when overcurrent due to breakdown occurs. The number of fast control command of the TSC is 14 for each
Table 1 Fast control command in TSC Item
Response time
Action
Number of command
Beam on Beam off Breakdown and arcing detection
200 s 200 s 200 s
GTO on GTO off GTO off
4 4 6
282
F. Okano et al. / Fusion Engineering and Design 83 (2008) 280–282
Table 2 Data of P-NBI control system per unit Type
Sampling time
Number of data
Gathering device CAMAC
Fast analog Slow analog Digital
10 ms 100 ms 400 ms
20 10 53
Analog Digital
100 ms 400 ms
83 136
Local panels
also gives a high extensibility to the PLC-based control system, because the programming and the component of the PLC are almost the same as other units. 3.2. Data acquisition The present data acquisition system consists of a CAMAC system and local control panels as shown in Table 2. The CAMAC system deals with three types of data such as fast analog, slow analog, and digital data at the sampling rates of 10, 100 and 400 ms, respectively. The local control panels gather the plant data of analog and digital signals at the sampling rate of 100 and 400 ms. The modern PLC can gather analog and digital data at the sampling rate of 100 ms for 100 s, so the remaining issue is to design the acquisition system of fast analog data for 100 s operation. We selected a PC-based off-the-shelf measurement device, WE7000, made by Yokogawa Electric Corporation. This device supports many kinds of modules for data acquisition. Indeed, it has a module to deal with 10 data channels at the sampling rate of 10 ms for 100 s. The data synchronization is within ∼90 s at every module, so the WE7000 with two modules is appropriate for the data acquisition system. Since the WE7000 has a Windows-based graphics toolkit to support rapid development in its standard package, we can develop the control program by using this toolkit. 3.3. Human–machine interface We will employ the SCADA (Supervisory Control And Data Acquisition) system for human machine interface, because the SCADA system is well developed and widely used due to its compatibility and reliability. The SCADA system gathers information from the PLCs and WE7000 via some form of network, and combines and formats the information to the operating personnel graphically. There are several SCADA software packages available. We selected the “RSView” software by Rockwell because we used this software in the previous work and are familiar with it [4]. This software is characterized by a lot of graphic
displays, and supports OPC (open connectivity) standards for fast, reliable communications, which allows us to program by ourselves. There are two keys to apply the SCADA to the new system. One is the data format interface between WE7000 and the PLC, because the RSView does not deal with both the fast sampling data of WE7000 and the low sampling data of the PLC, simultaneously. For the application of the SCADA, the data formatting program is to be developed to combine the two data groups into a data sheet. Second is to shorten the processing time on the control system with the analog data of ∼1300 channels and the digital data of ∼2300 channels for 12 units. The distributed processing system allows keeping the processing time constant even though the number of unit increases. We will develop the prototype control system for one unit so as to check the processing time. 4. Summary and future plan We have designed the PLC-based control system for the JT60SA P-NBI system. Most of the present components can be replaced by the PLC and PC-based data acquisition system, where the system programming can be done by ourselves without software developers. The main feature is to maintain high independent controllability between units. This structure allows a cost-effective control system because the programming of the PLC is almost the same as other units. We will develop the data acquisition system with the PLC and WE7000 in 2007. Then, we will construct the prototype control system for one unit so as to demonstrate the fast controllability of the beam current switch within 200 s. Based on the results of the prototype control system, the whole control system of 12 units will be completed by the end of 2012. References [1] M. Kikuchi, M. Matsukawa, H. Tamai, S. Sakurai, K. Kizu, K. Tsuchiya, et al., Overview of modification of JT-60U for the satellite tokamak program as one of the broader approach projects and national program, in: Synopsis for 21st IAEA Fusion Energy Conference, October 2006, Chengdu, China, 2006. [2] Y. Ikeda, N. Akino, N. Ebisawa, M. Hanada, T. Inoue, A. Honda, et al., Technical design of NBI system for JT-60SA, in: Proceedings of the 24th Symposium on Fusion Technology, September 2006, Warsaw, Poland, 2006. [3] S. Matsuda, M. Akiba, M. Araki, M. Dairaku, N. Ebisawa, H. Horiike, et al., The JT-60 neutral beam injection system, Fus. Eng. Des. 5 (1987) 85–100. [4] A. Honda, F. Okano, K. Ooshima, N. Akino, K. Kikuchi, Y. Tanai, et al., Application of PLC to dynamic control system for liquid He cryogenic pumping facility on JT-60U NBI system, in: Proceedings of the 6th IAEA Technical Meeting on Control, Data Acquisition, and Remote Participation for Fusion Research, June 2007, Inuyama, Japan, 2007.
Fusion Engineering and Design 83 (2008) 280–282
Design of a new P-NBI control system for 100-s injection in JT-60SA F. Okano a,∗ , S. Shinozaki a , A. Honda a , K. Ooshima a , S. Numazawa b , Y. Ikeda a a
Fusion Research and Development Directorate, Japan Atomic Energy Agency, Naka, Ibaraki-ken 311-0193, Japan b Streem Corporation, Hitachinaka, Ibaraki-ken 312-0062, Japan Available online 4 January 2008
Abstract Modification of JT-60U to a superconducting device (so-called JT-60SA) has been planned to contribute to ITER and DEMO. The positiveion-based NBI system (P-NBI) is required to inject 24 MW for 100 s with 12 units. The P-NBI control system is to be fully remodeled with PLC (Programmable Logic Controller), which is featured by high market availability, system extensibility, cost-effectiveness, and independent development in programming. One of the critical issues to apply the PLC to the P-NBI control system is to control quickly the high voltage power supplies within 200 s. For this purpose, the fastest PLC dealing with 4 refresh words at the processing time of 200 s is to be employed. The second issue is to construct a data acquisition system for such a large number of data channels (∼2300 digital and ∼1300 analog data channels). The use of PLC linked with PC-based data measurement devices via Ethernet allows processing the large number of channels. The third issue is to make the man–machine interface simple. The marketed software giving an easy product of graphic menus is available for PLC programming. From these results, it is expected that commercial PLC could be applied to the large-scale control system of the P-NBI system for 100 s operations. © 2007 Elsevier B.V. All rights reserved. Keywords: JT-60SA; Positive-ion-based NBI system; PLC; 100 s operations
1. Introduction The modification of the JT-60U to a fully superconducting coil tokamak, JT-60SA (Super Advanced), has been planned as the satellite device for the ITER (International Thermonuclear Experimental Reactor) [1]. The positive-ion-based NBI system (P-NBI), which will be the main heating system on JT-60SA, is required to extend its pulse duration from 30 to 100 s at the total injection power of 24 MW with 12 units [2]. To achieve this requirement of 100 s operation, the P-NBI heating system requires modification of the control system in addition to the power supply system. The P-NBI control system is to operate high power beams under communication with the JT-60 central control system [3]. Since the P-NBI control system was constructed more than 20 years ago, the system components such as local control panels are too old to reuse for the JT-60SA. Moreover, the present system employs the central control system to operate 12 units, which has a close relationship between units. This type of system relies totally on the reliability of every unit. Should there be a failure of some unit, the entire system is often down. To obtain a high reliable control sys-
∗
Corresponding author. Tel.: +81 29 2707433; fax: +81 29 2707449. E-mail address: [email protected] (F. Okano).
0920-3796/$ – see front matter © 2007 Elsevier B.V. All rights reserved. doi:10.1016/j.fusengdes.2007.11.014
tem, we intend to design a new control system for the JT-60SA P-NBI system. The design is based on a distributed control system using the modern PLC. The relationship between units is to be reduced as much as possible. This allows simplification of the control system and to allows straightforward expansibility of the multi-unit control system. Furthermore, the new system is intended to be constructed by the user itself, without the need for a custom-made program written by a software developer. 2. Design concept for P-NBI control system 2.1. Present system Fig. 1 shows the present P-NBI control system. The CP1 is composed of the earliest PLC and a TDG (Timing Distribution Generator) to distribute the beam-on timing to the CP2 of each unit. The CP2 is a fast controller to turn on/off the beam current in response to the CP1’s command. The TSC (Timing Sequence Controller) in the CP2 gives the timing to all components, such as gas injection, filament, arc, deceleration, acceleration, deflection coil, canceling coil, and fast shutter. It also turns off the beam current to protect the high voltage components (ion source) against breakdowns. In the CP1 and CP2, these functions are produced by customized circuit boards with memory IC.
F. Okano et al. / Fusion Engineering and Design 83 (2008) 280–282
281
Fig. 1. Present P-NBI control system.
Fig. 2. Designed control system for JT-60SA.
The workstations (W/S) were introduced to manage multiunits operation, to handle a large amount of data, and to communicate with the JT-60 central control computer. Each unit can be operated independently as far as the interface between the workstations and others units is not interrupted.
unit as shown in Table 1. A customized IC chip in the CP2 controls the acceleration power supply. In our survey of the PLC technical progress, one of the fastest PLCs, made by Yokogawa Electric Corporation, can deal with 4 refresh words (1 word: 16 I/O) in a processing time of 200 s so long as the programming steps are less than 2.8 K. Thus, the PLC can communicate 16 data with 4 I/O units, which satisfies the fast controllability requirement for the high voltage power supply. For other commands to the sub-systems for gas injection, filament, etc., the time response is to be less than 100 ms where normal PLCs are available. The PLC has a remote-control function with a fiber-optic communication system, the so-called FA-Bus. This function allows controlling the local control panels (I/O units) ∼200 m away from the central control room without specific communication setup. The transmission speed is 10 Mbps so that we do not worry about the I/O refresh time and in ladder programming. The PLC network is FL-net to provide intercommunication between different type of PLCs, such as the fastest PLC and normal PLCs. The FL-net is the open controller level network which is the result of a standardization initiative of JEMA (Japan Electrical Manufactures Association). There are 12 P-NBI units, each of which is to be independently controlled. In the case of plasma injection, it is necessary to synchronize the injection timing with other units. The timing of beam injection is delivered to each unit from the JT-60 central control system via the hardware, without a softwareinduced time delay. This simple interface enhances the reliability of unit operation even though other units are down. This structure
2.2. Design requirements The key issue for the new control system is to keep high reliability, expandability, and continuity with the functions of the present control system. To realize such a control system, the design concept was decided as follows: (a) The control system should be composed of commercially marketed components, which are well supported by manufacturing company in order to easily obtain replacement parts. (b) The control system is to be a distributed control system for each unit, which allows operating each unit independently. (c) The control system should be simplified as much as possible to ensure high reliability. (d) The other important key was to construct the control system by the user itself to reduce the cost of constructing a new system. 3. PLC-based control system The modern PLC is an attractive control device to construct the P-NBI control system. Fig. 2 shows the designed PLC-based P-NBI control system. There are three keys to apply the PLC to the P-NBI control system. 3.1. Fast controllability In the present control system, the GTO (Gate turn-off thyristor) switch in the high voltage power supply should be turned on/off within 200 s when overcurrent due to breakdown occurs. The number of fast control command of the TSC is 14 for each
Table 1 Fast control command in TSC Item
Response time
Action
Number of command
Beam on Beam off Breakdown and arcing detection
200 s 200 s 200 s
GTO on GTO off GTO off
4 4 6
282
F. Okano et al. / Fusion Engineering and Design 83 (2008) 280–282
Table 2 Data of P-NBI control system per unit Type
Sampling time
Number of data
Gathering device CAMAC
Fast analog Slow analog Digital
10 ms 100 ms 400 ms
20 10 53
Analog Digital
100 ms 400 ms
83 136
Local panels
also gives a high extensibility to the PLC-based control system, because the programming and the component of the PLC are almost the same as other units. 3.2. Data acquisition The present data acquisition system consists of a CAMAC system and local control panels as shown in Table 2. The CAMAC system deals with three types of data such as fast analog, slow analog, and digital data at the sampling rates of 10, 100 and 400 ms, respectively. The local control panels gather the plant data of analog and digital signals at the sampling rate of 100 and 400 ms. The modern PLC can gather analog and digital data at the sampling rate of 100 ms for 100 s, so the remaining issue is to design the acquisition system of fast analog data for 100 s operation. We selected a PC-based off-the-shelf measurement device, WE7000, made by Yokogawa Electric Corporation. This device supports many kinds of modules for data acquisition. Indeed, it has a module to deal with 10 data channels at the sampling rate of 10 ms for 100 s. The data synchronization is within ∼90 s at every module, so the WE7000 with two modules is appropriate for the data acquisition system. Since the WE7000 has a Windows-based graphics toolkit to support rapid development in its standard package, we can develop the control program by using this toolkit. 3.3. Human–machine interface We will employ the SCADA (Supervisory Control And Data Acquisition) system for human machine interface, because the SCADA system is well developed and widely used due to its compatibility and reliability. The SCADA system gathers information from the PLCs and WE7000 via some form of network, and combines and formats the information to the operating personnel graphically. There are several SCADA software packages available. We selected the “RSView” software by Rockwell because we used this software in the previous work and are familiar with it [4]. This software is characterized by a lot of graphic
displays, and supports OPC (open connectivity) standards for fast, reliable communications, which allows us to program by ourselves. There are two keys to apply the SCADA to the new system. One is the data format interface between WE7000 and the PLC, because the RSView does not deal with both the fast sampling data of WE7000 and the low sampling data of the PLC, simultaneously. For the application of the SCADA, the data formatting program is to be developed to combine the two data groups into a data sheet. Second is to shorten the processing time on the control system with the analog data of ∼1300 channels and the digital data of ∼2300 channels for 12 units. The distributed processing system allows keeping the processing time constant even though the number of unit increases. We will develop the prototype control system for one unit so as to check the processing time. 4. Summary and future plan We have designed the PLC-based control system for the JT60SA P-NBI system. Most of the present components can be replaced by the PLC and PC-based data acquisition system, where the system programming can be done by ourselves without software developers. The main feature is to maintain high independent controllability between units. This structure allows a cost-effective control system because the programming of the PLC is almost the same as other units. We will develop the data acquisition system with the PLC and WE7000 in 2007. Then, we will construct the prototype control system for one unit so as to demonstrate the fast controllability of the beam current switch within 200 s. Based on the results of the prototype control system, the whole control system of 12 units will be completed by the end of 2012. References [1] M. Kikuchi, M. Matsukawa, H. Tamai, S. Sakurai, K. Kizu, K. Tsuchiya, et al., Overview of modification of JT-60U for the satellite tokamak program as one of the broader approach projects and national program, in: Synopsis for 21st IAEA Fusion Energy Conference, October 2006, Chengdu, China, 2006. [2] Y. Ikeda, N. Akino, N. Ebisawa, M. Hanada, T. Inoue, A. Honda, et al., Technical design of NBI system for JT-60SA, in: Proceedings of the 24th Symposium on Fusion Technology, September 2006, Warsaw, Poland, 2006. [3] S. Matsuda, M. Akiba, M. Araki, M. Dairaku, N. Ebisawa, H. Horiike, et al., The JT-60 neutral beam injection system, Fus. Eng. Des. 5 (1987) 85–100. [4] A. Honda, F. Okano, K. Ooshima, N. Akino, K. Kikuchi, Y. Tanai, et al., Application of PLC to dynamic control system for liquid He cryogenic pumping facility on JT-60U NBI system, in: Proceedings of the 6th IAEA Technical Meeting on Control, Data Acquisition, and Remote Participation for Fusion Research, June 2007, Inuyama, Japan, 2007.