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MAGNET DEVELOPMENT AND INSTRUMENTATION 2009Pulsed energy supplyThe 14 MJ capacitor bankThe 14 MJ capacitor bank (see figure 166) has functionedwithout any major problems. The financial contributionby the European Union based on the number of performedpulses requires a stricter accounting system for the use ofthe generator. A simple logging system was already inoperation. The arrival of Jean-Pierre Nicolin, a professionalinformatics engineer, permitted us to implement afull-featured database containing coils, users, pulses andother relevant data. He developed a system that includescontrolled access based on a password. Implementing thisin the Siemens Step7 software was possible but not straightforward,nevertheless, one can now load the user-rights andpassword via a file containing all the accepted proposals.use with the old control unit for the 150 kJ bank. The useof this central unit severely limits the versatility of the 1 MJbank since it can only be used at a repetition rate of 1 (fullenergy) pulse every 20 minutes and the commutation optionis not operational. Due to the professional informaticssupport we were able to greatly improve and stabilize thesoftware interface between the old (150 kJ) central moduleand the outside world (direct user interface or controlvia the ESRF “SPEC” system). An interface with the samelook and feel (but partly based on different hardware) isnow being written for the new (1 MJ) central module. Theassembly of the central module is reaching completion, butdue to unforeseen long delivery times of the optically firedthyristors (a delay of 1 year to get a viable offer with a deliverytime of 40 weeks!) we will be obliged to cannibalizethe 150 kJ unit (i.e. the thyristor stack of the 150 kJ unitwill be dismounted and temporarily used in the 1 MJ unit).The final test of the central (charging) unit is foreseen forJanuary 2010.Figure 166:basement.A view of the 14 MJ, 24 kV, 65 kA generator in theFigure 167: The developed in-house, rapid commutation switch,for changing automatically the polarity of the field.The construction of a 1 MJ transportable capacitorbankDriven by the success and the frequent use of the transportable150 kJ bank (ILL, ESRF) we decided to build a1 MJ capacitor bank. This new unit is not only a higherenergy version of the 150 kJ generator but it has two essentialmodifications. First of all it will have the possibilityto work with two polarities, and secondly the chargingand the commutation (see figure 167) will take only a fewminutes and will be controlled completely by a computerintegrated in the central charging unit. For budgetary reasonsit was decided to first build the two storage modulessince they could in principle be energized by the existingcharger unit (at the expense of a long charging time). Sincethe first quarter of 2009 the two capacitor modules are inOutlookThe most important and urgent investment is a moderatelysized (∼ 6 MJ) capacitor bank with a short pulse. Thisequipment will permit us to energize coils in the 80 T rangewithout making compromises in the design. It is foreseenthat the installation will be built as two completely independent3 MJ units. Each unit will consist of a mediumsize container. The use of containers has two advantages: ifrequired one can use more than 1 MJ at remote sites (ILL,ESRF, etc.) and secondly the delivery and use of the 6 MJgenerator can start before the extension of the building hasbeen finalized. The foreseen use of several generators imposesa review and a profound modification of the groundingstrategy. This long due modification needs to be finalizedin 2010.P. Frings, B. Griffe, J.-P. Nicolin, T. Schiavo118