Abstract: An adapter for use in monitoring the deterioration of an oil insulated transformer due to pyrolysis that allows for an alarm to be generated at the desired ppm values is provided. The adapter is configured to sample the headspace of the main transformer tank as well as the adjacent compartments of a transformer and pass it over a common sensor to check for gases indicative of pyrolysis. During this constant monitoring process, the device will alert the end user when there is an increase in monitors gases. This will allow the owner to take the transformer off line and perform other diagnostic tests to determine the extent of damage to the equipment.

Abstract: A statistical method is described to interpret partial discharge (PD) measurement data from rotating machines for the maintenance personnel. Cumulative damage to the electrical insulation caused by PD during an observation time window is estimated using multiple PD sensors strategically distributed along the entire length of the machine winding. The damage thus estimated is compared against a reference value based on the annual averages of similar machines to determine if maintenance action is needed and how soon, if required. A method is also described to track the electrical insulation's overall condition and generate real-time health status alerts continuously and reliably.

Abstract: A system and method for assessing and modeling operation of a transformer includes a controller connected to a power transformer. The controller is configured to calculate theoretical information related to operation of the power transformer, assess information related to actual operation of the power transformer, and manipulate one of more parameters associated with one or more equations used to calculate the theoretical information so that the calculated theoretical information more closely approximates the information associated with the actual operation of the power transformer. In a preferred embodiment, the controller is configured to automatically manipulate the parameters associated the theoretical calculation of operation of the power transformer although the controller may also be configured to request user confirmation of manipulation of one or more of the parameters of the equations associated with the theoretical calculations related of expected actual operation of the power transformer.

Abstract: A system and method for estimating a temperature of a fluid contained in an electrical device such as a transformer, circuit breaker, or reactor without direct thermal communication with the fluid is disclosed. The method includes measuring a temperature of an exterior wall of a housing of the electrical device, measuring an ambient temperature around the housing, and estimating a temperature of the fluid within the housing using the measured wall temperature and the measured ambient temperature. In a preferred aspect, the method also adjusts the estimated fluid temperature for one or more of ambient humidity conditions, conductive, convective, and radiation heat transfer properties associated with operation of the underlying electrical device.

Abstract: An on-load tap changer position sensor includes a series of radially spaced reed switches and a magnetic indicator that is rotated by a shaft that is coupled directly or indirectly to a load tap changer. As the position of the magnetic indicator changes, the location of the magnetic field created by the magnetic indicator moves. Each reed switch includes a set of contacts that close when in the presence of the magnetic field. The closed contacts create a voltage differential that is detected and used to determine the location of the closed reed switch and thus the position of the on-load tap changer.