A welding-type power supply that receives alternating current (AC) input power and converts the AC input power to direct current (DC) power to provide power for welding tools. The welding-type power supply is configured to detect whether single phase AC power or three-phase AC power is connected to the input of welding-type power supply. Single phase input power may be detected by sampling ripple voltage of the DC power, either synchronously with the AC input power or synchronously with a signal generated by an output of the welding-type power supply.

An isolated switched-mode power converter converts power from an input source into power for an output load. Power switches within a primary-side power stage control the amount of power input to the power converter and, ultimately, provided to the output load. A digital controller on the secondary side of the power converter generates signals to control the power switches. This controller also senses a rectified voltage on the secondary side of the power converter and uses this sensed voltage to detect fault conditions of the primary side. For example, the sensed rectified voltage is used to detect undervoltage or overvoltage conditions of the input power source of the power converter, or faulty power switches within the primary-side power stage.

An actively driven pressure relief system for a container, a building, an enclosure, or a cubicle with an electrical installation, the actively driven pressure relief system includes a panel. The system further includes a fault detection device for detecting an arc fault in the electrical installation of the container, the building, the enclosure or the cubicle; and a triggering unit for triggering an opening signal for the panel upon detection of an arc fault by the fault detection device. A panel opening mechanism opens the panel in a destructive manner. Further, a container, building, enclosure or cubicle with an actively operated pressure relief system is described. A method for relieving pressure from a container with a panel and an electrical installation inside the container is also described.

An actively driven pressure relief system for a container, a building, an enclosure, or a cubicle with an electrical installation, the actively driven pressure relief system includes a panel. The system further includes a fault detection device for detecting an arc fault in the electrical installation of the container, the building, the enclosure or the cubicle; and a triggering unit for triggering an opening signal for the panel upon detection of an arc fault by the fault detection device. A panel opening mechanism opens the panel in a destructive manner. Further, a container, building, enclosure or cubicle with an actively operated pressure relief system is described. A method for relieving pressure from a container with a panel and an electrical installation inside the container is also described.

A control device for an MMC is disclosed. The control device for an MMC including a plurality of converter arms that include a plurality of sub-modules connected in series and that are connected to a DC link includes: an arm controller, which detects the arm current of a converter arm so as to determine whether a DC failure has occurred, and, if it is determined that the DC failure has occurred, transmits a bypass control signal for protecting a sub-module and notifies of the DC failure; a sub-module controller for controlling the sub-module so as to bypass a DC failure current according to the bypass control signal received from the arm controller; and a main controller, which detects, in real-time, the arm current of the converter arm and a voltage (DC link voltage) of the DC link, determines whether the DC failure is a temporary DC failure or a permanent DC failure on the basis of the detected arm current and DC link voltage if the occurrence of the DC failure is notified by the arm controller, and transmits, to the arm controller, a normal operation control signal for normal operation of the sub-module or a bypass control signal for bypassing of the DC failure current.

A control device for an MMC is disclosed. The control device for an MMC including a plurality of converter arms that include a plurality of sub-modules connected in series and that are connected to a DC link includes: an arm controller, which detects the arm current of a converter arm so as to determine whether a DC failure has occurred, and, if it is determined that the DC failure has occurred, transmits a bypass control signal for protecting a sub-module and notifies of the DC failure; a sub-module controller for controlling the sub-module so as to bypass a DC failure current according to the bypass control signal received from the arm controller; and a main controller, which detects, in real-time, the arm current of the converter arm and a voltage (DC link voltage) of the DC link, determines whether the DC failure is a temporary DC failure or a permanent DC failure on the basis of the detected arm current and DC link voltage if the occurrence of the DC failure is notified by the arm controller, and transmits, to the arm controller, a normal operation control signal for normal operation of the sub-module or a bypass control signal for bypassing of the DC failure current.

The problem to be solved is to provide a system and a method to protect the regulator rectifiers from the reverse voltage condition and the short circuit condition, and the problem is solved in the present invention by a system and a method that use a protection device including a control unit that receives an input from the circuit based on the reverse voltage condition and the short circuit condition, and based on the existence of at least one of the condition or a combination thereof, the control unit switches a switching unit from an ON state to an OFF state, thereby breaking the circuit between the regulator rectifier device and the load section, thus protecting the regulator rectifier device.

A first converter station is part of a high voltage direct current transmission system that includes a DC transmission link connected to the first converter station a second converter station. A DC current and a DC voltage of the DC transmission link are sensed by the first converter station. It is determined that the sensed DC current is equal to or larger than a threshold current value, that the sensed DC current is equal to or larger than the threshold current value, and that at least a partial recovery of the sensed DC voltage has occurred. On the basis that it is determined that the at least a partial recovery of the sensed DC voltage has occurred, it is determined that a phase-to-ground fault has occurred. In response to determining that a phase-to-ground fault has occurred, a power delivered by the first converter station can be reduced.

Methods, systems, and devices for protecting a wireless power transfer system. One aspect features a sensor network for a wireless power transfer system. The sensor network includes a differential voltage sensing circuit and a current sensing circuit. The differential voltage sensing circuit is arranged within a wireless power transfer system to measure a rate of change of a voltage difference between portions of an impedance matching network and generate a first signal representing the rate of change of the voltage difference. The current sensing circuit is coupled to the differential voltage sensing circuit and configured to calculate, based on the first signal, a current through a resonator coil coupled to the wireless power transfer system.

A power conversion circuit having a solid-state circuit breaker integrated therein is disclosed. With a disconnect switch between a utility source and the power conversion apparatus described for meeting UL489, the power conversion circuit includes an input connectable to an AC source, a rectifier circuit connected to the input to convert an AC power input to a DC power, and a DC link coupled to the rectifier circuit to receive the DC power therefrom. The rectifier circuit comprises a plurality of phase legs each including thereon an upper switching unit and a lower switching unit, wherein at least one of the upper and lower switching units on each phase leg comprises a bi-directional switching unit that selectively controls current and withstands voltage in both directions, so as to provide a circuit breaking capability that selectively interrupts current flow through the rectifier circuit, while maintaining original power conversion functionalities.