The present disclosure relates to a docking module for a current transformer comprising: an electronic circuit and at least one electric connecting element for electrically coupling the circuit to the current transformer and for docking the docking module onto the current transformer.

Methods and systems for controlling a circuit designed to protect electrical equipment, in particular sensitive power grid equipment such as transformers, are disclosed. In particular, methods of local and remote control of operation of protection circuits are provided that allow for remote access to change an operational mode of such protection circuits, while ensuring that power grid equipment is protected locally regardless of any configuration instructions received from a remote or centralized facility. Override levels may be set to ensure power grid transformer protection, regardless of operational mode or remote instruction.

A method for protecting a low-voltage distribution network. The low-voltage distribution network includes a low-voltage side of a three-phase distribution transformer that is configured to supply electrical power to at least one single-phase load through a respective distribution line of a plurality of three-phase distribution lines distribution lines. The method includes measuring variations of a periodic neutral-to-ground voltage between a neutral terminal of the three-phase distribution transformer and a local ground node by sampling the variations at a sampling frequency, detecting a fault in the low-voltage power distribution network based on the variations of the periodic neutral-to-ground voltage, and disconnecting the low-voltage side from the low-voltage power distribution network responsive to the fault being detected.

A protective circuit for a current transformer for preventing a secondary voltage on a secondary circuit of the current transformer from exceeding a secondary voltage threshold. A protective circuit input can be coupled to the secondary circuit of the current transformer such that the secondary voltage is applied to the protective circuit input. A control unit is connected to the protective circuit input. A switch unit is connected to the protective circuit input and is operatively connected to the control unit. The control unit is adapted to provide a control signal to the switch unit in response to the secondary voltage exceeding the secondary voltage threshold. The switch unit is adapted to short-circuit the protective circuit input in response to the control signal provided by the control unit. The switch unit is implemented as a semiconductor circuit.

The power supply apparatus has a configuration in which a temperature detection element and a voltage division resistance element are connected in series as a voltage division unit for an output voltage from a secondary side of a transformer of the power supply apparatus, and stops output of the power supply apparatus based on an output from the voltage division unit.

A testing device tests an intelligent electronic device of a power system. A PC generates failure data by performing: simulation calculation for a CT and a PT with respect to current waveform data of a current transformer and voltage waveform data of a potential transformer based on a characteristic of an instrument transformer; and simulation calculation for an MU with respect to the current waveform data of the current transformer and the voltage waveform data of the potential transformer based on a characteristic of the MU. The testing device acquires device information data indicating a circuit breaker of the power system, in synchronization with the failure data. The testing device transmits the failure data and the device information data to the intelligent electronic device via a process bus in accordance with a setting of outputting data to the process bus and a setting of sampling.

The power supply apparatus has a configuration in which a temperature detection element and a voltage division resistance element are connected in series as a voltage division unit for an output voltage from a secondary side of a transformer of the power supply apparatus, and stops output of the power supply apparatus based on an output from the voltage division unit.

A high-voltage transducer includes a housing, which spatially encloses at least one electrical measuring device and an insulating gas. The insulating gas is clean air, with which electrical insulation in the housing of the high-voltage transducer is carried out. A method for measuring with the high-voltage transducer is also provided.

A system for compensating for a back emission current in an X-ray generator is provided. The system includes a transformer, a common, and a voltage source. The transformer is operative to provide power to an electron emitter of the X-ray generator. The common is electrically coupled to an anode of the X-ray generator. The anode is operative to receive electrons emitted by the electron emitter such that the back emission current is generated between the common and the electron emitter. The voltage source electrically couples the common to the transformer and is operative to generate an offset voltage that reduces the back emission current.

A system for protecting a transformer is provided. The system includes an inductor electrically disposed between the transformer and a load powered by the transformer, and a resistor electrically disposed in parallel with the inductor between the transformer and the load.