A cooling fan variable-frequency control system for a power transformer includes a control device and a fan unit. The control device includes a microprocessor that is set with a first temperature range, a second temperature range higher than the first temperature range, and a fan switching time. The microprocessor is connected to a temperature sensor for detecting a temperature of an insulating oil in a power transformer. A variable-frequency controller and a fixed-frequency controller are connected to the microprocessor and are connected to a switching controller. The fan unit is connected to the switching controller and includes first and second fans. The microprocessor controls the switching controller according to the fan switching time to thereby control the variable-frequency controller to connect with the first fan or the second fan. The first fan and the second fan can operate at a fixed frequency and at a variable frequency.

The invention relates to a bursting device (1) for a high-voltage device (2). The bursting device (1) is suitable in particular for on-load tap changers or high-voltage transformers filled with a filling medium such as gas or oil. The bursting device (1) according to the invention has a bursting cork (3) with support blocks (7) arranged on the inner surface (3B). A shear pin (8) is in arranged in each receiving block (7), said shear pin being divided into a first portion (8A) and a second portion (8B). The first portion (8A) of the shear pin (8) protrudes into the receiving block (7). The second portion (8B) of the shear pin (8) is arranged below the circumferential edge (9) of an opening (5) of the high-voltage device (2).

A power system having a transformer and integrated power conditioning device is disclosed. The transformer includes a fluid enclosure that holds transformer fluid therein that immerses a core and coil assembly. The power conditioning device is integrated with the transformer and connected thereto to receive an output power and is within an electrical enclosure. A power conditioning circuit is configured to perform power conversion and conditioning on the output power from the transformer. A first set of electrical conductors is coupled between the core and coil assembly and the power conditioning circuit to transfer the output power from the transformer to the power conditioning circuit and a second set of electrical conductors is coupled between the power conditioning circuit and electrical connections on a front plate of the fluid enclosure, the second set of electrical conductors being routed through the fluid enclosure of the transformer.

A subsea substation system including: an oil-filled water impermeable enclosure; an AC-transformer, and at least one overcurrent device electrically connected to the AC-transformer, the at least one overcurrent device, the AC-transformer, and the electrical connections between them are accommodated in the oil-filled water impermeable enclosure, wherein the enclosure includes thermal zones within the enclosure, wherein the AC-transformer is arranged in a first thermal zone and the overcurrent devices are arranged in a second thermal zone of the enclosure, a thermal layer separate the first thermal zone and the second thermal zone, the at least one thermal layer is configured to allow oil flow between the thermal zones while reducing heat flow between the zones.

A method for using forecasting power transformer faults may include receiving dissolved gas data of power transformers; receiving features of the power transformers; generating, based on the features and the dissolved gas data, clusters of transformers, wherein each respective cluster of the clusters comprises transformers exhibiting similarities to each other; selecting, for each respective cluster and respective gas of the first dissolved gas data, from among machine learning models trained to minimize a difference between a forecast gas concentration and an actual gas concentration, a machine learning model; generating, using a selected machine learning model, a forecasted concentration of the respective gas of the respective cluster; estimating, using forecasted gas concentration, a ROC of the respective gas of the respective cluster; predicting, based on a comparison of the ROC to an ROC alarm threshold, a future fault of a transformer; and generating an alert indicating the transformer maintenance is required.

A fault gas detection system for a liquid filled high voltage transformer, the transformer including a main tank and an expansion tank the tanks fluidic connected by an exchange conduit such that gas and/or a transformer liquid is able to exchange between the tanks, the gas detection system including: a chamber with a top cover, a predefined horizontal level-plane in the chamber defining a maximum liquid level of a transformer liquid in the chamber during use, a fluid-channel including a fluid-egress at a level equal to or higher than the top cover and a fluid-ingress lower than the level of the level-plane, a level sensor designed to measuring and/or indicating a liquid level. A respective transformer and a respective wind turbine system is also provided.

An immersion cooled inductor includes an inductor at least partially submerged in cooling liquid and a localized boiling feature operable to instigate boiling of the cooling liquid prior to oversaturation.

A device including a high voltage apparatus enclosing a fluid for providing cooling and/or electrical insulation of the apparatus, and a detector for one or more physical properties of the fluid positioned spaced apart from the housing. The device includes a pipe assembly for housing a fluid, whereby the pipe assembly is arranged between the detector equipment and the housing such that the fluid is extended without interruption in the pipe assembly. The fluid in the pipe assembly is in communication with the fluid in the housing, and the detector equipment is in direct communication with the fluid in the pipe assembly. The detector equipment is positioned below a top level of the housing and at a safe distance from the housing of the apparatus, which makes it possible to carry out inspection, testing, maintenance, and calibration of the detector equipment without taking the high voltage apparatus out of operation.

A system and method for preventing a transformer from catching the fire due to internal faults is provided. The system includes a first set of sensors, a timer connected to the first set of sensors, a first breaker, a set of relays and a controller. The first set of sensors is configured to sense the generation of arc. As soon as the arc is detected, incoming supply to the transformer is isolated and the timer is triggered for a pre-determined time to measure the duration for which the faulty condition is persisting in the transformer. This faulty condition will be sensed through the set of relays. When such an abnormal condition persists for a duration set on the trigger of the system, beyond which the controller issues a signal to isolate the power supply. A method of using the system for preventing fire due to internal faults is also disclosed.

The faulty transformer partial discharge, vibration, combustible gases, and sound frequency monitor and alarm is an electric circuit. The faulty transformer partial discharge, vibration, combustible gases, and sound frequency monitor and alarm is a diagnostic tool. The faulty transformer partial discharge, vibration, combustible gases, and sound frequency monitor and alarm comprises a control circuit, a housing structure, and a transformer structure. The housing structure contains the control circuit. The housing structure attaches the control circuit to the transformer structure. The control circuit captures audible sounds generated by the transformer structure. The control circuit analyzes the captured audible sounds.