Time filter

Source Type

Albuquerque, NM, United States

Vandiver B.,Omicron Albuquerque Inc.
2015 68th Annual Conference for Protective Relay Engineers, CPRE 2015 | Year: 2015

This paper is part two of the subject title and identifies some of the developing issues in testing what has here to fore been well understood protection elements we commonly used in designing modern protection systems. The core issue is the complexity of today's combined protection element scheme logic that enables these 'understood' protection elements to function more securely and reliably - but also prevent us from using legacy testing techniques to prove and verify the defined characteristic. Additionally, it makes a comparison of the commonly used test methods (step change and ramping) focusing on common differential elements of many bus, generator, and especially transformer relays and how they now react based on their algorithms and logic. It identifies why these test methods fall short, under what conditions they should and should not be used and what techniques are now required to properly test today's relays. © 2015 IEEE.

Apostolov A.,Omicron Albuquerque Inc.
2015 68th Annual Conference for Protective Relay Engineers, CPRE 2015 | Year: 2015

This paper discusses the traditional approach to field testing a series compensated line protection system. The problem domain is analyzed to establish the various test cases required to prove the local/remote protection system and the difficulty in using traditional testing methods in creating effective tests, whether local only or End-to-End tests. Techniques are identified to break down the testing so conventional test approaches can be used, but these often require compromising the integrity of the IED settings and missing the overall scheme operation. These technical challenges are examined to identify what tools are needed to resolve them. The paper then explores using a network simulation tool to directly create the proper system conditions that the series compensation protection system requires to verify correct operations for all power system faults without compromising the IED setup. It discusses the payback levels of investing in proper preparation and training required for using a network simulation tool. It presents a real case study of field testing a series comp scheme and the potential time savings of the test method employed. © 2015 IEEE.

Duplessis J.,Omicron Albuquerque Inc. | Duplessis J.,SmartSenseCom Inc.
IEEE Transactions on Industry Applications | Year: 2015

The variable frequency power factor (PF) (VFPF), frequency response of stray losses (FRSL), and dynamic dc winding resistance tests are reviewed in this paper. These electrical field tests provide new and significant diagnostic detail and thereby enable a more comprehensive assessment of the condition of a transformer. These tools are not radically different from three standard electrical tests that have been in use for decades in the industry. In fact, the test setup, connections, and test implementation requirements from a tester's perspective are identical to those for the PF, leakage reactance, and dc winding resistance tests, respectively. The subject electrical field tests have progressed from these traditional tests, gaining their unique assessment capabilities by simply expanding the related standard test's measurement(s) in the frequency or time domain. VFPF, FRSL, and dynamic dc winding resistance tests do not displace these older diagnostic tools but rather supplement them, bringing considerable and, in the case of the VFPF test, disproportionately more value. © 1972-2012 IEEE.

Apostolov A.,Omicron Albuquerque Inc.
2012 65th Annual Conference for Protective Relay Engineers | Year: 2012

Adaptive protection of distribution feeders is a powerful tool for reducing the fault clearing time and improving the quality of service. The paper describes adaptive features in multifunctional Intelligent Electronic Devices (IEDs), as well as distribution protection schemes that adapt to changing substation and system conditions. © 2012 IEEE.

Koch M.,Omicron Albuquerque Inc. | Prevost T.,Omicron Electronics Corporation United States
IEEE Transactions on Dielectrics and Electrical Insulation | Year: 2012

This paper describes the unique characteristics of the oil-paper insulation system utilized in power transformers, their influence on the dielectric response and means for proper modeling of these characteristics. Dielectric response measurement between windings of a power transformer is used to estimate the water content of the solid insulation. By measuring the dielectric response over a wide frequency range different properties of the insulation materials can be determined. These properties can be modeled in a laboratory so that measured response can be compared to modeled response with known properties. This comparison enables the estimation of properties of the materials such as water content and conductivity. The influences of temperature, aging and insulation geometry are described. Case studies are presented which demonstrate the validity of the test method. The influence of frequency range, temperature, aging byproducts, oil conductivity and insulation material type on the accuracy of the moisture estimation is discussed. © 1994-2012 IEEE.

Discover hidden collaborations