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.