H02H7/1252

INPUT OVERVOLTAGE PROTECTION CIRCUITS FOR POWER SUPPLIES

A power supply includes a power converter, a protection circuit, and a control circuit. The protection circuit includes an input for receiving an input voltage, an output for providing an output voltage to the power converter, a first switching device coupled in a current path between the input and the output, and a second switching device coupled across the first switching device. The control circuit is configured to sense the input voltage and the output voltage, in response to the output voltage exceeding a first defined threshold, turn off the first switching device and turn on the second switching device to supply power to the power converter, and in response to the input voltage exceeding a second defined threshold, turn off the second switching device to disconnect the power source from the power converter. Other example power supplies and protection circuits are also disclosed.

VOLTAGE CONVERTER HAVING OVERVOLTAGE PROTECTION

To provide improved overvoltage protection for a voltage converter for converting an input voltage into a DC output voltage, a first switch-off unit is provided, which is configured to effect a switch-off of at least a part of the voltage converter if the DC output voltage reaches or exceeds a first voltage threshold, in order to reduce the DC output voltage. Furthermore, a second switch-off unit is provided, which is configured to check whether a mean value of the DC output voltage reaches or exceeds a mean value threshold and, if the mean value threshold is reached or exceeded, to effect a switch-off of at least a part of the voltage converter in order to reduce the DC output voltage.

APPARATUS FOR OPENING OR CLOSING A DC CIRCUIT, AND METHOD FOR AUTOMATICALLY CLOSING A DC CIRCUIT
20220020544 · 2022-01-20 · ·

A device is for opening or closing a DC circuit with at least one busbar. The device includes an electric switch for opening or closing the DC circuit; a fault current detector; a trigger unit and a precharging device. The electric switch opens the DC circuit via the trigger unit upon a fault current being detected by the fault current detector. Further, the precharging device restores the voltage on the busbar prior to closing the electric switch. The device further includes a control unit for automatically closing the electric switch after the pre-charging process.

Power supplies with limited power protection and relevant control methods

A power supply is configured to limit its output power, converting an input voltage on a primary side into a bus voltage on a secondary side. A current-sense resistor detects a bus current output from the power supply to provide a current-sense signal. A bus switch is electrically connected to a secondary winding on the secondary side, configured to selectively supply power to the bus voltage. A power delivery controller controls the bus switch in response to the current-sense signal and a power detection signal on the secondary side. The power delivery controller provides a power threshold in response to the bus voltage, compares the power detection signal with the power threshold, and turns off the bus switch to stop supplying power to the bus voltage if the power detection signal exceeds the power threshold, thereby limiting the output power of the power supply.

METHOD FOR COORDINATING PROTECTIVE DEVICES IN A DISTRIBUTION GRID
20220172914 · 2022-06-02 · ·

In a method for coordinating a distribution grid of different levels of electromechanical switches and automatically electrically closable apparatuses in a DC circuit, the distribution grid is arranged between feed-in devices and loads and includes at least one busbar. Each of the apparatuses includes an electrical switch to open or close the DC circuit, a fault current detection device, a tripping unit, and a pre-charging apparatus.

ELECTRICAL NETWORK

An electrical network is equipped with feed-in devices, loads, a distribution grid arranged therebetween, at least one semiconductor switch, and at least one electromechanical switch for separating a feed-in device or a load in the event of a fault. The feed-in devices and loads are arranged in groups which are connected together by a busbar and paired semiconductor switches. Each feed-in device and load can be separated from the grid by an electromechanical switch in the event of a fault, and the individual groups of feed-in devices and loads can be separated from one another by the semiconductor switches in the event of a fault in order to prevent cross currents on the busbar.

ELECTRICAL NETWORK
20220200275 · 2022-06-23 · ·

An electrical network includes feed-in devices, loads, and a distribution grid, which is arranged therebetween and comprises at least one busbar and at least one device for opening or closing a DC circuit. The at least one device includes: an electric switch for opening or closing the DC circuit; a fault current detection device; a trigger unit; a precharging device; and a control unit for automatically closing the electric switch after the precharging process. The electric switch opens the DC circuit via the trigger unit if a fault current is detected by the fault current detector, and the precharging device restores the voltage on the busbar prior to closing the electric switch. Multiple loads can be individually electrically separated via a respective electromechanical switch, and multiple loads can be electrically separated as a group via the at least one device.

Overvoltage protection

The present disclosure relates to a device including a rectifying bridge including: a branch connected between first and second nodes; another branch including first and second MOS transistors series-connected between the first and second nodes and having their sources coupled together; a resistor connecting the gate of the first transistor to the second node; another resistor connecting the gate of the second transistor and the first node; and for each transistor, a circuit including first and second terminals respectively connected to the drain and to the gate of the transistor, and being configured to electrically couple its first and second terminals when a voltage between the first terminal of the circuit and the first terminal of the other circuit is greater than a threshold of the circuit.

Electronic device, protection circuit and protection method using the same

A protection circuit including an auxiliary winding, a rectifier unit, the filter unit, a voltage divider unit and a controller is provided. The auxiliary winding is configured to induce an AC voltage. The rectifier unit is coupled to the auxiliary winding and configured to rectify the AC voltage into a DC voltage. The filter unit is coupled to the rectifier unit and configured to filter the DC voltage into a DC filter voltage. The voltage divider unit is coupled to the rectifier unit and the filter unit to transmit the DC filter voltage. The controller is coupled to the voltage divider unit and configured to detect a partial voltage of the DC filter voltage and detect whether to activate a protection mechanism according to the partial voltage.

Converter arrangement having a phase module arrester and method for short-circuit protection thereof

A converter arrangement includes a converter phase extending between first and second DC voltage poles. The converter phase includes an AC voltage terminal, a first converter arm extending between the first DC voltage pole and the AC voltage terminal and a second converter arm extending between the AC voltage terminal and the second DC voltage pole. The first converter arm includes a first series circuit of two-pole switching modules and the second converter arm includes a second series circuit of two-pole switching modules. Each of the switching modules includes power semiconductor switches and an energy store. A phase module arrester in an arrester branch is parallel with the two series circuits of the switching modules. The phase module arrester is configured for overvoltage protection of the switching modules of the two series circuits. A method for short-circuit protection of the converter arrangement is also provided.