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DEVELOPMENT OF ELECTRIC MOTORS AND GENERATORS FOR OPERATION IN LIQUID DIELECTRIC ENVIRONMENTS AT

CRYOGENIC TEMPERATURES

ETUDE SUR LA MISE AU POINT DE MOTEURS ET DE GENERATRICES ELECTRIQUES FONCTIONNANT EN MILIEU

LIQUIDE DIELECTRIQUE A CRYOTEMPERATURE

Russell Shively Vice President & General Manager

Electric Motor Division Ebara International Corporation

Sparks, Nevada, U.S.A. Rshively@ebaraintl.com

ABSTRACT This paper discusses the development, design and performance characteristics of 3-

phase random wound and formwound squirrel-cage motors and generators while operating submerged in liquefied gases at cryogenic temperatures. Through a combination of field experience and laboratory testing, motors designed to operate in this unique environment have been evolving over the past 45 plus years. During this time, it has been determined that many of the problems normally associated with air motors, such as partial discharge, corona, thermal life and oxidation are absent on submerged motors. This has enabled engineers to select different materials and adapt designs to better tailor each motor to its specific application and to significantly reduce the physical size required for any given kW rating.

It has been suggested that motors operating in submerged cryogenic applications are inherently less efficient than equivalent rated air cooled machines. This is based on the premise that the friction losses encountered by a rotating body in a viscous fluid will be much greater than a body rotating in air. However, a detailed analysis and comparison of the segmented losses of identically rated air-cooled and submerged cryogenic motors reveals this is not necessarily the case.

In recent years new applications have been developed using submerged motor technology. One such use is motors being used as induction generators in applications where the isentropic thermodynamic properties of electricity generation can be effectively used to improve the efficiency of the gas liquefaction process.

RESUME Cet article examinera la mise au point, la conception et les caractéristiques de

rendement des moteurs et des génératrices à enroulement en vrac triphasé et à enroulement préformé à cage d’écureuil lorsqu’ils sont exploités immergés dans des gaz liquéfiés à cryotempérature. En associant les expériences sur le terrain et les essais en laboratoire, des moteurs créés pour fonctionner dans ce milieu particulier ont été développés durant les 45 dernières années. Pendant cette période, il a été établi que de nombreux problèmes habituellement liés aux moteurs pneumatiques, tels que la décharge

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partielle, l’effet de couronne, la longévité thermique et l’oxydation étaient inconnus en ce qui concerne les moteurs immergés. Ainsi, des ingénieurs ont pu sélectionner des matériaux différents, ajuster par leurs études de la meilleure manière possible chaque moteur à son application particulière et réduire de manière significative la taille physique nécessaire à tout régime nominal en kW.

On a avancé que les moteurs destinés à des usages immergés cryogéniques étaient par nature moins efficaces que des appareils de puissance équivalente à refroidissement par air. Cette affirmation s’appuie sur le fait que les pertes de charge rencontrées par un corps tournant dans un liquide visqueux seraient beaucoup plus importantes que celles rencontrées par un corps tournant dans l’air. Cependant, une analyse détaillée et une comparaison des pertes sectorielles entre des moteurs de puissance identique à refroidissement par air et des moteurs immergés cryogéniques montrent que tel n’est pas nécessairement le cas.

Ces dernières années, de nouveaux produits utilisant la technologie du moteur immergé ont été développés. Les moteurs sont alors utilisés comme des génératrices à induction dont les propriétés isentropiques thermodynamiques de production d’électricité peuvent réellement améliorer le rendement des processus de liquéfaction des gaz.

PRODUCT DESIGN DEVELOPMENT

The first motors for submerged cryogenic service were introduced in the late 1950’s and were immersed in liquid methane at -161°C. These used standard air motor technology with special lead cables. Since the rubber and neoprene insulations used on most lead cables of that period would not maintain their physical and dielectric integrity at cryogenic temperatures, PTFE insulated cables were utilized. All other designs, materials and processes were the commonly available insulations, steels and treatments used with air motors. Figure 1 depicts a typical submerged motor along with its integral pump/driver.

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Figure 1. Typical submerged pump and motor

Following the installation of these early designs, it was soon recognized that several

refinements needed to be made, both in designs as well as materials. While the motors were all capable of handling the required loads, differences in performance from predicted indicated they were not reacting in the same manner as would be expected if they were operating in air. Also, unusual failure modes began to appear which indicated the materials being used were not performing in the normally accepted manner.

One of the first things noted was an unusual number of groundwall failures at the ends of the stator slots on random wound machines. Different materials were tested in an attempt to increase the MTBF of the windings. When this did not work, multiple layers of materials were tried. Eventually it was determined that in order to have a satisfactory groundwall insulation at the ends of the slot, two physically different materials had to be layered to provide the necessary life. Two layers of identical materials would not work and neither would a single extra thick layer of material. The reason for this has never been adequately explained; although, it has been theorized that it is a function of the differences in thermal expansion between the lamination steel and the two dielectric materials.

The next improvement came in the area of treatment varnish. It was observed that polyester dip and bake varnishes would not hold up for extended periods at cryogenic temperatures. Tests by the G.E. insulation laboratory in Schenectady, NY in the late

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1970’s revealed that polyester varnishes tended to craze and crack after prolonged exposure to cryogenic environments. It was found that epoxy resins performed much better than polyesters at cryogenic temperatures and proved to be relatively inert when exposed to the liquid hydrocarbons commonly encountered in these applications. With the advent of VPI systems, 100 percent solids epoxy became the standard encapsulant for all cryogenic service windings.

About this time, several failures began to manifest themselves at power companies in Japan and ethylene facilities in Australia. These were all turn-to-turn failures deep within the stator slot on random wound machines. Upon investigation it was determined that this was a combination of two independent problem areas. First, it was felt that a portion of the failures could be attributed to small sections of wire in the slot not being fully bonded with the encapsulant epoxy. This could result in individual wires vibrating or flexing to the point where they eventually cracked from fatigue with the resultant arcing subsequently involving adjacent turns. Secondly, it was revealed that the power companies were experiencing numerous micro power interruptions every day. As there was no protective circuitry on the motors to protect them from the transient spikes generated by these power interruptions, the magnet wire insulation was breaking down turn-to-turn. As these failures were in a cryogenic environment, overheating did not occur and in all cases the motors did not drop off line and the arcing continued until the windings eventually shorted either phase-to-phase or phase-to-ground.

The solution was to change from a round film wire to a heavy coated poly-amide-imide (HAPTZ) insulated wire with a single layer of Dacron glass overcoat (FDG). This created an additional degree of physical separation between wires which addressed the turn-to-turn transient failure problems and provided a much better substrate for the treatment epoxy to bond with, all but eliminating voids within the slot. Once this change was made, the turn-to-turn failure rate dropped to zero. Further proof that this change was the proper solution to the transient spike condition occurred several years later on an application in Africa. Two motors had to be rewound for an unrelated problem and the repair facility inadvertently used film in place of FDG wire. When put back in service, the motors failed turn-to-turn almost immediately. Subsequent investigation revealed the change in magnet wire material and also determined that there were numerous daily power interruptions and transient voltage spikes on the grid. Repair of the motors using FDG wire in place of film wire cleared up the problem and there have been no further failures on these units after several years of operation.

OPERATIONAL CHARACTERISTICS

Recent investigations have revealed that the dielectric strength of many of the insulation materials commonly used on submerged cryogenic motors actually improves when immersed in a dielectric fluid at cryogenic temperatures.[1] This increase in breakdown strength can be anywhere from 1.5 to 3 times the strength of the same material in an ambient air environment. This has been verified during several insulation tests at Ebara International’s electric motor insulation lab. In one instance, an impulse voltage test was conducted on several sample coils insulated with a combination of HAPTZ insulated rectangular magnet wire, ½-lapped layered mica flake groundwall tape with a total thickness of 1.65mm, a 0.21mm thick polyester glass tape overwrap and VPI impregnated with a 100 percent solids epoxy resin. This is considered a nominal

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insulation system for a 3.3kV cryogenic motor. The test consisted of a voltage determined by the formula

(8Un + 5)kV. [1] where Un is the rated line to ground voltage of the stator winding , the rise time is <1.2 seconds and the voltage decays to half its peak in 50µs. As may be noted, this formula results in about twice the usual voltage for an impulse voltage test.[2],[3] The actual test was conducted at 31,400 volts with the coils submerged in liquid nitrogen. All coils passed the test without breakdown.

A second example consisted of a series of coils insulated with 1.83mm of mica tape and 0.21mm polyester glass armor tape. These were tested in liquid nitrogen, beginning at 25kV and increasing in 5kV steps to a maximum of 70kV. Leakage current was measured at each voltage step and the results plotted. No coils broke down during this test and the maximum leakage ranged between 90 and 140µA. Other tests have indicated coils in air will have a sharp increase in leakage current, or breakdown completely, at some point as the test voltage is being increased, while the same coils in a liquid dielectric show only a gradual increase in leakage throughout the same test range.

This characteristic gives the designer the option of reducing the amount of insulation in the slot, thus allowing more room for copper magnet wire with a concurrent reduction in I2R losses, or leaving the insulation at the same level as air motors thereby gaining a greater reliability with an improved MTBF.

It has been shown that a winding submerged in a cryogenic fluid is intrinsically free from damage from corona or partial discharge.[4] This is due to the higher breakdown stress of a liquid as compared to that of air at atmospheric pressure. Partial discharge, as defined by IEEE 100, is an electric discharge that only partially bridges the insulation between conductors, and may or may not occur adjacent to the conductor.[5] In order for partial discharge inception (PDIV) to occur, there must be minute voids within the insulation system which will allow ionization, along with sufficient voltage to initiate the discharge. However, if a winding is totally submerged in a dielectric fluid, any void which may be present in the insulation system quickly fills up with that liquid, either through direct displacement or through molecular migration. It is also well known that as temperature is reduced, partial discharge activity is reduced. Lastly, studies of high voltage transmission cables cooled with liquid nitrogen have shown that if the pressure on the cable is kept higher than atmospheric, this will inhibit the inception of any partial discharge.[6]

Tests on sample coils at Von Roll Isola USA have confirmed much of the preceding.[4] Several formed coils were deliberately manufactured with small voids in their insulation systems. These were then subjected to a series of Tan-δ tests. First, each coil was suspended in air at 28°C. and a Tan-δ test conducted. The coil was then suspended in the cold gas immediately above an open container of liquid nitrogen. This effectively displaced any oxygen and lowered the temperature of the coils to -161°C. Again a Tan-δ test was performed. Lastly, the coils were lowered into the liquid nitrogen itself and allowed to stabilize at -196°C., after which a final Tan-δ test was performed. The results of these tests are graphically displayed in figure 2.

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0.20.4

0.60.8

1.0

Tan Delt a @ -195C

Tan Delt a @ -161C

Tan Delt a @ 28C

-0.0010

0.0010

0.0030

0.0050

0.0070

0.0090

0.0110

0.0130

0.0150

Un Va l ue s

COIL ENVIRONMENT COMPARISON

Tan Delt a @ -195C Tan Delt a @ -161C Tan Delt a @ 28C

Figure 2. Tan-δ test results for sample coils in air, gas and liquid.

It may be seen that the initial test in air resulted in a relatively high Tan-δ. When

lowered into the cold gas, Tan-δ dropped significantly. Finally when the coils were completely submerged and the liquid had an opportunity to penetrate all voids throughout the insulation system, Tan-δ activity virtually ceased. It should be noted that none of these tests included an increased pressure cycle. Due to the logistics of the test, a pressure step could not be safely conducted. Based on testing done by others regarding the impact of pressure on PDIV, it may be safely concluded that had this been done, there would have been no Tan-δ activity of any sort during the final stage of testing.[6]

On submerged cryogenic motors, the same criteria that applies to the suppression of partial discharge also applies to corona. Again according to IEEE 100, the definition of corona is a luminous discharge due to ionization of the air surrounding a conductor caused by a voltage gradient exceeding a critical value.[5] This ionization and subsequent discharges will both erode the insulation system and slowly build up carbon deposits along the discharge tracks that will eventually lead to shorting and/or grounding of the winding. However, proper conditions must be present to allow this ionization and the inception of corona. In an atmosphere consisting entirely of a dielectric fluid, under pressures greater than atmospheric and at cryogenic temperatures these conditions cannot exist. Thus in a submerged cryogenic liquid dielectric environment, neither partial discharge nor corona can occur. This is further borne out by the fact that after 45 plus years of service and the installation of several thousand motors rated 5.5 kV and above, no evidence of corona or partial discharge damage has ever been observed on any of these motors.

It should also be noted that in cryogenic environments the temperature rise of the motors may be controlled by the volume of fluid passing through and around the winding and rotor. By completely submerging the motor directly in the liquid and providing a continuous flow of fluid through the air gap, the temperature rise of the complete motor may be minimized. Full-load dynamometer tests conducted at the US Electrical Motors’ Prescott, Arizona facility in the early 1980’s using liquid nitrogen as the cooling medium indicated that a properly designed motor and fluid flow system will limit the winding

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temperature rise to a range of 5 to 10°C. Recent full load tests on several motors at the Ebara International test facility in Sparks, Nevada using liquid methane at -161°C with embedded thermocouples and RTD’s in the winding’s slots and endturns have confirmed these earlier findings. Under these conditions, assuming an initial winding temperature of -161°C, the actual operating temperature of the winding will be somewhere on the order of -151°C. Under the premise that insulation life doubles for every 10°C decrease in temperature, extrapolating from the chart shown in figure 3, developed using IEEE 1 & 275 methods[7],[8], if the winding insulation system consists primarily of class F or better materials, at cryogenic operating temperatures its thermal life should be almost infinite. Indeed, in all the years that these motors have been in existence, there has never been a reported instance of a winding overheating except in the case of a locked rotor which, by definition, has no fluid flow and thus no cooling.

Figure 3. Life curves of insulation systems as a function of temperature.

These same tests revealed another property of submerged cryogenic motors that

separates them from air motors. Because of the cooling effect of the process fluid on the winding, embedded RTD’s, thermocouples and thermistors serve no useful purpose on this type of motor. It was found that these devices picked up temperature changes only within 25mm of the device. The heat sinking effect of the liquid flowing over and through the motor effectively carried away any heat from elsewhere in the windings. Thus the use of these types of devices for equipment condition monitoring is effectively negated. Further, should something occur that would stop the flow of cooling fluid through the motor, the weak link is usually not the winding, but rather the rotor which can heat up and fail before the winding has an opportunity to react. Because of this condition, in order to get accurate temperature readings during the dynamometer testing noted previously, it was necessary to use the winding resistance method of temperature detection to identify the overall temperature rise of the complete motor. This necessitated the use of special high speed laboratory measuring equipment as the winding resistance would begin to quickly change, due to the thermal heat sinking properties of the process fluid, the instant power was removed from the motor.

In addition to the almost perfect cooling experienced by motors in this environment, another benefit is the total absence of free oxygen. It is this condition that makes the motor’s environment intrinsically safe from ignition as oxygen must be present in order to initiate combustion. This also precludes the oxidation of any part of the insulation system as well as all iron and steel components of the motor, thus slowing the normal progression of system aging and degradation. It is not unusual for motors that have been

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in service for many years in a clean fluid environment to be as clean and problem free as when they were first installed.

A unique performance problem on cryogenic applications is a reduction in starting torque due to the very low resistance in the rotor’s aluminum bars brought about by the bar’s low resistivity when cooled to cryogenic temperatures. To compensate for this, motors were initially designed oversize such that their reduced starting torque would still be sufficient to accelerate the load, even under a reduced temperature environment. However, this practice has several drawbacks. Paramount among these is a concurrent increase in starting current. On applications with strong power grids, this is not too great of a concern; however, a large percentage of these motors are used in areas where power grids are marginal in capacity and DOL starting of large motors can have a dramatic impact on the stability of the grid. This problem is compounded by the common requirement that motors must be able to start at reduced voltages and still maintain relatively low lock-amp to full-load amp ratios.

To address this problem, new rotor bar and endring materials were developed that would retain much of their initial resistivity at cryogenic temperatures. This allowed the design of smaller motors which had lower starting currents, did not negatively effect weak power grids and generated sufficient starting torque to ramp their loads up to speed. Unfortunately this material also resulted in a reduction in performance of the motors at rated load. This reduction includes such factors as slower operating speeds, lower efficiencies and higher operating currents. Ongoing work on rotor slot geometries is being done in an effort to mitigate these problem areas. Additionally, alternate starting methods, such as auto-transformers, soft-starters and VFD’s, are being employed to reduce the impact of high starting currents while retaining the benefits of low resistivity materials in the rotor; however, it is incumbent upon both the motor and facility engineers to work closely together to optimize the motor design to best match the requirements of the application.

As may be seen from the preceding, properly designed motors with today’s insulation systems used in submerged cryogenic service operate in what amounts to an almost perfect environment. No oxidation. No heat. No ionization erosion. Those failures that do periodically occur can usually be attributed to external influences such as physical damage during manufacturing, foreign particles in the fluid stream, chemically reactive or conductive material in the process liquid or massive voltage transients such as lightning strikes or phase faults elsewhere on the power grid.

The environment within a dielectric liquid, at cryogenic temperatures, and the resultant effects of this environment on motor materials, has enabled engineers to develop motors that are capable of operating close to the magnetic limits of available electrical steels. Without heating or oxidation as a concern, limiting factors to kW capacity become the saturation levels within the electrical steel and manufacturing limitations to stack lengths on any given diameter. When these motors were initially developed, the limit was thought to be in the range of 400 to 500 kW. With the advent of today’s technology and materials, motors are being built as high as 2,500 kW and units are in the design stage with ratings in excess of 5 MW with voltages up to 7 kV.

In addition to motors in cryogenic fluids, work has been extended into the area of warmer fluids where some of the advantages of cryogenic temperatures are not present. Even without the cryogenic temperatures, warm dielectric fluids still present many

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advantages over air cooled machines. The lack of oxidation, enhanced heat sinking properties and intrinsic corona/partial discharge suppression of the fluids as they pass through and around the winding and rotor all allow for designs which are smaller and safer than equivalent ratings on air cooled machines. For comparison, figure 4 shows the physical difference between a 900 kW air cooled induction generator, along with its couplings, seals and driver, and a 1,000 kW submerged induction generator of the same speed and voltage which has an integrated driver and requires no couplings or seals.

Figure 4. Size comparison between in-air and submerged turbine generators.

An argument against the use of submerged motors has been that they are less efficient

than their air motor counterparts due to the high windage losses generated by the rotor spinning in a liquid environment. On the surface this would seem a reasonable observation. However, upon closer inspection of the motors most commonly encountered in cryogenic service, this argument fails.

If one were comparing identical physical packages, this argument would be correct. However, a submerged cryogenic motor of a given kW rating will typically be much smaller than the same rating on an air motor. This is primarily due to the temperature rise limitations discussed earlier. Since temperature rise is not normally an issue on submerged cryogenic motors, the designer may concentrate instead on the magnetic limits of the stator and rotor electrical steel. This usually results in a given rating being placed on a frame one or two sizes smaller than the same rated air motor. In addition, as the majority of process fluids are typically flammable, the air motor must be a UL rated class I, or equivalent, explosionproof machine. Thus for any given rating the air motor is physically larger, heavier and has losses in its cooling fans, bearings and ancillary devices that are not present in the submerged motor. At the same time, the submerged motor will usually have lower winding and rotor losses due to the effect of the cryogenic temperature on the resistivity of the winding’s copper and the rotor’s aluminum bars and endrings.

For example, in comparing a 373 kW, 2 pole, 3 phase, 60 hertz, 575 volt cryogenic motor with its vertical TEFC counterpart, it was found that the I2R winding and rotor losses were both significantly lower on the cryogenic motor. The windage losses were also lower, even after the increase in friction due to the fluid in the air gap. This is a

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direct result of the much smaller diameter rotor on the submerged cryogenic motor. Refer to table 1 for a tabulation of these segmented loss values and size comparisons.

Table 1. Segmented losses of identical rated air and cryogenic motors

Motor O.D. Wt Ws Wr FW Other Air 622.30 3,130 3,579 3,318 9,454 8,059

Cryogenic 431.80 413 2,243 2,769 8,918 9,794

Note O.D. is the stator diameter in mm, Wt the total motor weight in Kg, Ws the stator watts loss, Wr the rotor watts loss, FW the friction & windage watts losses and Other all additional watts losses in the motors.

As may be seen from the table, in this particular example the submerged motor is physically smaller, weighs approximately 2,717 Kilograms less and has fewer losses, thus a higher efficiency, than the identical rating on a vertical explosionproof motor.

In the end, when efficiencies are compared on identically rated motors the different losses and gains on each machine will generally offset one-another and there will be little to no difference between them. In a worse case condition, a cryogenic motor may be no more that a few tenths of a point lower in efficiency than its air motor equivalent; but, it will always be smaller and lighter regardless of other criteria.

Recently, applications outside of the pump field have been developed for submerged motor technology. Paramount among these is the development of submerged induction generators. This application requires machines to be either fixed speed generators or variable speed-constant frequency devices.

An integral part of the gas liquefaction process is a rapid reduction from high to low pressure of the condensate fluid. Existing technology accomplishes this through the use of a Joule-Thompson valve. The drawback to this is that this is an isenthalpic process that puts heat back into the expanded gas.[9] The same pressure reduction may be achieved by replacing the JT valve with a turbine generator. Generators are essentially isentropic devices which remove energy from the gas stream to generate electricity.[10] This reduction in energy reduces temperature, rather than increasing it, and allows the expanded gas to be processed much more economically.[11],[12]

From the generator’s perspective, a fixed speed constant output device is no different than a submerged motor operating as an in-air induction generator. Other than the fact that the generator is submerged in a liquid dielectric, the same technologies apply for both the control circuitry and the generator itself. Figure 5 depicts a typical submerged turbine generator.

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Figure 5. Typical submerged turbine generator.

Variable speed-constant output generators are similar to some of the latest generation

wind and water turbines in that they incorporate the latest generation of IGBT controlled VFD’s to automatically adjust the excitation frequency of the generator to match the rotational speed generated by the fluid flow through the turbine. This continuous adjustment allows for a constant frequency output through the VFD and back into the power grid.

An interesting side note to this application is the fact that the improvement in efficiency to the liquefaction plant is high enough solely through the reduction in condensate temperature that the power generated by the induction generator may be dumped into a load bank and simply dissipated as heat. However, if the power generated is put back into the grid, even more savings may be realized. Because of this, this type of equipment has the fastest payback time of any other in the petrochemical industry.[13]

REFERENCES CITED

1. Husain, E., et.al, “Dielectric Behavior of Insulation Materials Under Liquid Nitrogen”, in Proceedings of the EIC/EMCW Electrical Insulation Conference, Cincinnati, Ohio, 2001.

2. Shell Oil DEP 33.66.05.31-GEN (1/99).

3. IEEE Guide for Testing Turn-to-Turn Insulation on Form-Wound Stator Coils for Alternating-Current Rotating Electric Machines, IEEE Std 522-1992

4. Shively, R.A. and Miller, H., “Development of a Submerged Winding Induction Generator for Cryogenic Applications”, in Proceedings of the IEEE Electrical Insulation Conference, Anaheim, California, 2000.

5. The Authoritative Dictionary of IEEE Standards Terms, 7th Ed., IEEE Std. 100-1992

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6. Bulinski, A. and Densley, J., “High Voltage Insulation for Power Cables Utilizing High Temperature Superconductivity”, IEEE Electrical Insulation Magazine, vol. 15, no. 2, pp. 14-22, 1999

7. IEEE Recommended Practice-General Principles for Temperature Limits in the Rating of Electrical Equipment and for the Evaluation of Electrical Insulation, IEEE Std. 1-2000

8. IEEE Recommended Practice for Thermal Evaluation of Insulation Systems for Alternating Current Electric Machinery Employing Form-Wound Preinsulated Stator Coils for Machines Rated 6,900 V. and Below, IEEE Std. 275-1992

9. Kimmel, H.E., PhD., “Speed Controlled Turbine Expanders”, Hydrocarbon Engineering, December /January 1998/99.

10. Habets, G.L., et.al, “Specification Method to Optimize Power Generation”, in Proceedings of the 61st American Power Conference, Illinois Institute of Technology, Chicago, 1999.

11. Cengel, Y.A., PhD., and Kimmel, H.E., “Power Recovery Through Thermodynamic Expansion of Liquid Methane”, in Proceedings of the 59th Annual American Power Conference, Illinois Institute of Technology, Chicago, 1997.

12. Legoy, P.R., “Utility Requirements for Power Recovery in the Cryogenic and Chemical Industry Using Variable frequency Drives in the Regenerative Mode”, IEEE Power Engineering Society Summer Meeting, July, 1999.

13. Hylton, E.H. and Kimmel, H.E., “Exducer Turbines, the Optimized Solution for LNG Expanders”, in Proceedings of the 2002 Gas Technology Conference, Doha, Qatar, 2002.

Russell Shively graduated from Arizona State University in 1986 with a Bachelor of Science Degree and took his Masters studies at the University of Missouri in St. Louis. He worked for the U.S. Electrical Motors Division of Emerson Electric for 27 years as a senior design and development engineer and was instrumental in the development and production of modern submerged cryogenic motors. For the past 15 years he as been employed by the Ebara International Corporation in Sparks, Nevada, most recently as Vice-President and General Manager of Ebara’s Electric Motor Division. Mr. Shively has authored several IEEE papers on electrical insulation systems, submerged cryogenic motors and generators and has presented papers at international IEEE conferences. He is also a contributing author to “Motor Application and Maintenance Handbook” published by the McGraw-Hill Book Co. and has published numerous articles on motor design and construction in several industry trade journals.