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The synchronous motor is a type of alternating current motor. Like an induction motor, it has a stator and a rotor. Its stator winding closely resembles that of an induction motor, and it, too, receives AC power from the power source to drive the connected load. Synchronous motors are available with various rotor designs to fit different applications. In one type, for example, the rotor is constructed somewhat like a squirrel-cage rotor.
Podded propulsion is prevalent in the marine industry. Podded propulsion systems provide many advantages to the ship owner, including increased propulsion efficiency and reduced construction cost. To evaluate the potential of a new pod configuration, a prototype machine was constructed and tested. This prototype machine was mainly constructed of composite parts. The propeller, housings, structural blading, motor canning, and fairings were constructed of composite materials. Composite materials were chosen as a cost saving, schedule reduction, performance enhancement, and as a technology demonstration. This paper will review the unit construction, and test results, focusing on the lessons learned for the composite part manufacture.
This paper provides the validation test results of preheat sequence applied to induction motors at two Test Facilities and offshore application for operation in the Gulf of Mexico. Although the objective of preheating Induction Motors (IM) is to lower the viscosity of the lubricant oil by 2 orders of magnitude (from 1000 cP to 10cP) for extending Electric Sumersible Pump (ESP) run life, this paper is exclusively focused on motor preheating results. The motor is energized with low voltage at a frequency of 120Hz maintaining the voltage low enough in order to keep the supplied shaft torque under the system's breakaway torque; thus the shaft never spins. The Medium Voltage Drive (MVD) is a Variable Frequency Drive output power determines heat rate that is adjusted to obtain temperature slope of 1 F/min specified by the project. The motor is modeled electrically and magnetically through Finite Element Analisys (FEA) to estimate its power losses; the motor internal temperatures can be predicted by the Motor-CAD (Computer-Aided Design) thermal model which is calibrated by winding resistance change and skin tempeperature measurement.
Refai, Ahmed (Agiba Petroleum Company) | Abdou, Hesham A.M. (Agiba Petroleum Company) | Seleim, Ahmed (Agiba Petroleum Company) | Biasin, Giovanni (Agiba Petroleum Company) | Reda, Walid (Novomet Egypt) | Letunov, Dmitry (Novomet Egypt)
The majority of Western Desert wells (Agiba Petroleum Company) are completed with artificial lift systems and several kind of pump: ESP, Sucker Rod, PCP (about 40 ESP, 250 Sucker Rod and 10 PCP). A new technology - Permanent Magnet Motor (PMM) - has been developed for ESP motors as alternative to conventional asynchronous induction motor in the last years. PMM is synchronous motor in which the stator manufacturing technique is similar to that of conventional asynchronous motor, but rotor has permanent magnets (instead of copper winding). PMM has more benefit of conventional induction motor: high efficiency (90 94%) vs. induction motors up to 86%; smaller size and weight; wider ranges of rotation frequency regulation (100-1000, 1000-4200 and 3000-6000 r.p.m.); reduced energy consumption and rating of surface equipment (Power Saving); stable torque over wide operation range; Power factor is near to 1; lower specific heat release due to higher efficiency. Also indirect benefits are: a) low heat release (minimum cooling fluid velocity 0.05 ft/s); b) less size for cable and lower power rating for transformer and VSD; c) decreased reactive power; d) improved system Power factor. All Agiba ESP wells are equipped with conventional induction motor. In the middle of June of 2012 Agiba performed a trial installation of Novomet PMM replacing an ESP unit with induction motor on well North Nada 1 x (oil well - Qg =315 BFPD, Qn=173 BOPD) of North Nada field. The installation was successful achieving the expected results and benefits in term of low power consumption. Successful key point: keeping electrical system stability and minimize the number of shutdowns; minimum cost for power consumption and production.
Beginning in 1992, the U.S. and Canada enacted efficiency standards forindustrial electric motors and other electrical components. Over the years, thescope of these regulations continues to raise the level of efficiency and alsowiden the coverage across motors 1 - 500 horsepower. Other countries arefollowing the lead of North America and establishing their own standards.
As we mandate premium efficiency levels, many incentive programs have beendiscontinues because of "free ridership". This may result in more old lessefficient motors being rewound rather than replaced with premium designs.
Testing in North America must be done by a certified lab but this is notnecessarily the case elsewhere. In some countries, the tests must be performedby a government lab, even though the motors were tested in a certified labelsewhere. These requirements may hamper U.S. exports and act as protection fordomestic manufacturers.
Verification and compliance in the U.S. may not be working well. Electricmotors embedded in equipment are to comply with the Energy Policy Act of 1992(EPAct) and Energy Independence and Security Act of 2007 (EISA) regulations butmay not be getting the proper inspection. This may result in domestic machinerymanufacturers being at a disadvantage to imported goods.
The impact on motor performance, on motor installation requirements, on powersystems as a whole, and on overall process efficiencies are discussed.
On one hand we pass laws meant to reduce electricity use and carbon emissions,but the results are that they may have the opposite effect.