The subject of the application is a power electronic tap changer module for transformer using power electronic elements connected to sections of a primary winding of the transformer. The power electronic tap changer module is equipped with valves having a pair of a thyristor or transistors connected with a controller and the valves are connected in series with the fuses, respectively. The module is equipped with an additional oversized tap line having an oversized valve rated for short circuit current, which valve is connected with an overvoltage triggering circuit. The oversized valve is equipped with a pair of thyristor or transistors connected with a thermally protected voltage suppressing device.

The subject of the application is a power electronic tap changer module for transformer using power electronic elements connected to sections of a primary winding of the transformer. The power electronic tap changer module is equipped with valves having a pair of a thyristor or transistors connected with a controller and the valves are connected in series with the fuses, respectively. The module is equipped with an additional oversized tap line having an oversized valve rated for short circuit current, which valve is connected with an overvoltage triggering circuit. The oversized valve is equipped with a pair of thyristor or transistors connected with a thermally protected voltage suppressing device.

The present disclosure relates to a method of monitoring switching by an on-load tap changer (OLTC) 1 from a first contact 3a to a second contact 3b of a transformer winding 2. The method includes measuring a voltage of the transformer. The method also includes measuring a temperature of the OLTC. The method also includes, based on the measured voltage and temperature, determining whether the switching from the first contact to the second contact has been successful.

The present disclosure relates to a method of monitoring switching by an on-load tap changer (OLTC) 1 from a first contact 3a to a second contact 3b of a transformer winding 2. The method includes measuring a voltage of the transformer. The method also includes measuring a temperature of the OLTC. The method also includes, based on the measured voltage and temperature, determining whether the switching from the first contact to the second contact has been successful.

A protection arrangement for an uninterruptible power supply system including at least one vacuum circuit breaker connected in series with an inductive element, the protection arrangement including a first bypass branch and a first grounding branch, the first bypass branch being connected in parallel with the inductive element and including two series-connected protective components of a first type and a bypass branch midpoint between them, where the first grounding branch is connected between the bypass branch midpoint and ground and includes a first grounding surge arrester.

A protection arrangement for an uninterruptible power supply system including at least one vacuum circuit breaker connected in series with an inductive element, the protection arrangement including a first bypass branch and a first grounding branch, the first bypass branch being connected in parallel with the inductive element and including two series-connected protective components of a first type and a bypass branch midpoint between them, where the first grounding branch is connected between the bypass branch midpoint and ground and includes a first grounding surge arrester.

The invention is concerned with a monitoring device, method and computer program product for monitoring a transformer having a tap changer. The transformer has at least two magnetically coupled windings and a tap changer having impedance elements and a changeover switch configured to gradually pass the impedance elements when changing between two tap changer positions during a tap change operation. The method is performed in the monitoring device and including: obtaining waveforms of measured power transmission properties recorded at the first and second transformer sides, processing the recorded waveforms for obtaining at least one waveform (Ploss) representing a tap change operation, and extracting information indicative of the performance of the tap change from the at least one waveform that represents the tap change operation.

The invention is concerned with a monitoring device, method and computer program product for monitoring a transformer having a tap changer. The transformer has at least two magnetically coupled windings and a tap changer having impedance elements and a changeover switch configured to gradually pass the impedance elements when changing between two tap changer positions during a tap change operation. The method is performed in the monitoring device and including: obtaining waveforms of measured power transmission properties recorded at the first and second transformer sides, processing the recorded waveforms for obtaining at least one waveform (Ploss) representing a tap change operation, and extracting information indicative of the performance of the tap change from the at least one waveform that represents the tap change operation.

An submarine cable system includes a first and a second submarine cable circuit branches arranged in parallel between an onshore BSP and an offshore BSP, and a first and a second bus reactor circuits arranged in parallel and connected to the onshore BSP. The first and second submarine cable circuit branches each includes a first circuit breaker, a submarine cable circuit, and a second circuit breaker connected in series, a first line reactor of which one end is grounded and another end is connected between the submarine cable circuit and the first circuit breaker, and a second line reactor of which one end is grounded and another end is connected between the submarine cable circuit and the second circuit breaker. The first and second bus reactor circuits each includes a bus reactor and a circuit breaker connected in series. An example switching method for this system is also disclosed.

An submarine cable system includes a first and a second submarine cable circuit branches arranged in parallel between an onshore BSP and an offshore BSP, and a first and a second bus reactor circuits arranged in parallel and connected to the onshore BSP. The first and second submarine cable circuit branches each includes a first circuit breaker, a submarine cable circuit, and a second circuit breaker connected in series, a first line reactor of which one end is grounded and another end is connected between the submarine cable circuit and the first circuit breaker, and a second line reactor of which one end is grounded and another end is connected between the submarine cable circuit and the second circuit breaker. The first and second bus reactor circuits each includes a bus reactor and a circuit breaker connected in series. An example switching method for this system is also disclosed.