Mechanical Testing of High Voltage Stator Insulation Systems

Maughan, Clyde V.; Gibbs, E. E.; Giaquinto, E. V.

doi:10.1109/tpas.1970.292779

Cited by 15 publications

(3 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Its purpose is to insulate the turn conductors from each other and from the core. All insulation systems are susceptible to mechanical and thermal damage [1], and their ability to maintain their insulating property can be greatly affected by pollutants such as dirt, oil, and moisture [2].…”

Section: Introductionmentioning

confidence: 99%

Employing the Peltier Effect to Control Motor Operating Temperatures

et al. 2023

View full text Add to dashboard Cite

Electrical insulation failure is the most common failure mechanism in electrical machines (motors and generators). High temperatures and/or temperature gradients (HTTG) are the main drivers of insulation failure in electrical machines. HTTG combine with and augment other destructive effects from over-voltage, to voltage transients, overload and load variations, poor construction techniques, and thermal cycling. These operating conditions cause insulation damage that leads to electrical insulation failure. The insulation failure process is greatly accelerated by pollutants and moisture absorption. A simple and robust way to reduce HTTG and moisture adsorption is by maintaining constant internal temperatures. The current method to maintain elevated internal temperatures and reduce condensation issues is by internal electrical heating elements. This paper examines the effectiveness of applying thermoelectric coolers (TECs), solid-state heat pumps (Peltier devices), as heaters to raise a motor’s internal temperature by pumping heat into the motor core rather than heating the internal air. TEC technology is relatively new, and the application of TECs to heat a motor’s internal volume has not previously been explored. In this paper, we explore the hypothesis that TECs can pump heat into a motor when out of service, reducing the HTTG by maintaining high winding slot temperatures and eliminating condensation issues. This paper describes a test motor setup with simple resistive heating (traditional method), compared with the application of TECs with heat sinks, heat pipes, and a water circulation heat exchanger, to gauge the capability of TECs to heat the inner core or winding area. In this paper, we demonstrate the full integration of TECs into a motor. The results show that each of the systems incorporating the TECs would effectively pump heat into the core and keep the winding hot, eliminating condensation issues and water ingress due to thermal cycling.

show abstract

Section: Introductionmentioning

confidence: 99%

Employing the Peltier Effect to Control Motor Operating Temperatures

et al. 2023

View full text Add to dashboard Cite

show abstract

“…Electrical motors fail for a variety of reasons [1,2] but 40% of motor failures are attributed to electrical insulation failure [3,4]. For motors and generators, a key factor leading to winding electrical insulation failure is insulation aging [5], where abrasion issues and micro-cracking effectively thins the insulation [6].…”

Section: Introductionmentioning

confidence: 99%

Research in Life Extension of Electrical Motors by Controlling the Impact of the Environment through Employing Peltier Effect

et al. 2022

View full text Add to dashboard Cite

This paper explores the application of thermoelectric cooler/heater (TEC) modules (Peltier heat pumps devices) to control core and winding temperatures, aiming to reduce the effects of thermal cycling and moisture issues that affect the life of electrical machines. Electrical windings in a motor will fail for a variety of reasons, and a major contributor to adverse effects of a motor’s life is humidity. Due to thermal cycling, air containing moisture is drawn into a motor through a variety of access points such as terminal boxes, bearings, end covers and mounting systems. Even spare or replacement motors specially stored in heated spare equipment stores suffer from moisture ingress because of normal daily temperature changes. The better a machine can be kept warm, the less it is affected by moisture and the effects of mechanical stresses from cycling temperatures. A series of experiments were conducted, whereby a TEC was attached to a section of motor core and was set up to pump heat into the core segment. The thermal properties of the core material and the capacity to control winding temperatures along the core in specific locations and over time was measured. The results of this research demonstrate that the temperature of the motor can be tightly controlled, thus enabling the reduction of the effects of moisture, and reducing core and winding temperature differences. This has a positive influence in reducing the thermal stresses, which will result in improved insulation life and machine reliability.

show abstract

“…The first of these are: (1) an IEC Report titled "Principal Aspects of Functional Testing: Aging Mechanisms and Diagnostic Procedures " ;…”

Section: Introductionmentioning

confidence: 99%

Multi-factor insulation system functional tests

Boulter

1976

1976 IEEE International Conference on Electrical Insulation

View full text Add to dashboard Cite

Insulation system characterization in industry, through work in IEEE and IEC, is evolving from thermal aging functional tests to multi-stre s s aging functional te sts. The latter approach includes all significant aging factors, a ffecting the insulation systems of specific equipment, in the functional test programs. The technical basis for using these complex tests and considerations in designing and inte rpreting them are reviewed, ba sed on the expe rience obtained in using multi-factor te sts, to evaluate the insulation systems of medium-size turbine generators in the author's company. The relationship of these tests to single-factor functional and materials properties tests is discussed.

show abstract

Mechanical Testing of High Voltage Stator Insulation Systems

Cited by 15 publications

References 2 publications

Employing the Peltier Effect to Control Motor Operating Temperatures

Employing the Peltier Effect to Control Motor Operating Temperatures

Research in Life Extension of Electrical Motors by Controlling the Impact of the Environment through Employing Peltier Effect

Multi-factor insulation system functional tests

Contact Info

Product

Resources

About