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The Brookhaven AGS is a strong focusing accelerator which is used to accelerate protons and various heavy ion species to equivalent maximum proton energy of 29 GeV. The AGS Main Magnet Power Supply (MMPS) is a thyristor control supply rated at 5500 Amps, +/-go00 Volts. The peak magnet power is 49.5 Mwatts. The power supply is fed from a motor/generator manufactured by Siemens. The motor is rated at 9 MW, input voltage 3 phase 13.8 KV 60 Hz. The generator is rated at 50 MVA its output voltage is 3 phase 7500 Volts. Thus the peak power requirements come from the stored energy in the rotor of the motor/generator. The rotor changes speed by about +/-2.5% of its nominal speed of 1200 Revolutions per Minute. The reason the power supply is powered by the Generator is that the local power company (LIPA) can not sustain power swings of +/- 50 MW in 0.5 sec if the power supply were to be interfaced directly with the AC lines. The Motor Generator is about 45 years old and Siemens is not manufacturing similar machines in the future. As a result we are looking at different ways of storing energy and being ablemore » to utilize it for our application. This paper will present simulations of a power supply where energy is stored in capacitor banks. The simulation program used is called PSIM Version 6.1. The control system of the power supply will also be presented. The average power from LIPA into the power supply will be kept constant during the pulsing of the magnets at +/-50 MW. The reactive power will also be kept constant below 1.5 MVAR. Waveforms will be presented.« less

January Progress--A kick-off meeting was held in San Diego with Alturdyne on January 21st. The proposed hybrid gas/electric chiller/cogenerator design concept was discussed in detail. The requirements and functionality of the key component, a variable speed, constant frequency motor/generator was presented. Variations of the proposed design were also discussed based on their technical feasibility, cost and market potential. The discussion is documented in a Trip Report. February Progress--After significant GRI/Alturdyne discussion regarding alternative product design concepts, the team made a decision to continue with the proposed product design, a hybrid chiller capable of also providing emergency power. The primary benefits are: (a) the flexibility and operating cost savings associated with the product's dual fuel capability and (b) the emergency power feature. A variable speed, constant frequency motor/generator would significantly increase the cost of the product while providing marginal benefit. (The variable speed, constant frequency motor generator is estimated to cost $25,000 versus $4,000 for a constant speed version). In addition, the interconnection requirements to the electric grid would significantly limit market penetration of the product. We will proceed with a motor/generator design capable of serving as the electric prime mover for the compressor as well as the generator for emergencymore » power needs. This component design is being discussed with two motor manufacturers. The first generation motor/generator will not be a variable speed, constant frequency design. The variable speed, constant frequency capability can be an advancement that is included at a later time. The induction motor/synchronous generator starts as a wound rotor motor with a brushless exciter and control electronics to switch between induction mode and synchronous mode. The exciter is a three-phase exciter with three phase rotating diode assembly. In the induction motor mode, the field windings are shorted out by SCRs located across the field. In the synchronous mode, a small ct on one of the exciter leads would power the rotating exciter electronics. Upon sensing exciter current, the electronics would automatically open the SCRs allowing synchronous operation. Quotes will be obtained from American Motor and Reuland, two motor/generator vendors. March Progress--A product layout was completed. The width is reduced significantly from the original hybrid design because the evaporator and condenser tube in shell heat exchangers are located below the engine/motor/compressor drive-line. Alturdyne is searching for a consultant to perform a drive-line torsional analysis. This analysis is necessary to ensure that the drive-line is not subject to undue vibrations operating through its entire speed range. Much effort was directed toward motor/generator selection. A decision was made to use Reuland Electric. A motor with double-end shafts will be purchased. The design effort which will be completed at Alturdyne will involve the modification of the wound rotor motor to also provide synchronous power. Work has been completed on developing the new controller which will be utilized for the original hybrid product as well as this advanced product. Work continues toward developing a manufacturing cost estimate. A detailed bill of material will be developed for the product. Key components include the engine, compressor and motor/generator.« less

LOFT primary coolant system motor generator (PSMG) switchgear boxes were analyzed for sliding and overturning during a seismic event. Boxes are located in TAN-650, Room B-239, with the PSMG generators. Both boxes are sufficiently anchored to the floor.

The LOFT Primary System Motor Generator Set was analyzed for sliding and overturning during a seismic event. The assembly is located in TAN 650, Room B239, and is satisfactory against seismic loading.

This study evaluates the capability of the vital batteries (PPS) to provide electrical power via the vital DC-AC motor generator sets to the LOFT PPS loads during severe cold weather conditions. It is concluded that these batteries while at a temperature of 5/sup 0/F will supply the necessary PPS electrical loads for a time in excess of the one hour permitted to start the diesel generators and are, therefore, adequate at this temperature. This Revision B of the LTR includes revised, more recent, and complete technical data relating to MG set efficiency, battery operating procedures and cold temperature derating. Revision B supersedes and replaces all previous issues.

The Bevatron operated an average of 80% of the scheduled operating time with the exception of one 5-day shutdown period for emergency maintenance of the motor generator sets. The machine was shut off l9% of the scheduled operating time because of component failure and 1% at the request of the user. During and following the Christmas shutdown period an ultrasonic inspection was made of the flywheel keyway on each of the motor generator sets. No faults were apparent. Charpy samples were taken from the inspection bore in the flywheels. Subsequent"vee notch" Charpy impact tests indicated that the flywheels are operated in a brittle region rather than in the ductile range expected. The research program again was devoted mainly to study of pi - and K-meson interactions. (auth)

The transient behavior of the electrical system for the Berkeley bubble- cahmber magnets under certain emergency procedures is examined theoretically. Conditions for nonoscillating behavior of the magnet current are derived. (auth)