A power supply delivery system is provided. The power supply delivery system includes a source module and a load module. The source module includes an input coupled to a Class 1 power source, plural outputs coupled to plural Class 2 cables, and circuitry coupled to the input and the plural outputs. The circuitry splits power received via the input into a plural Class 2 channels and conducts the plural Class 2 channels to the plurality of outputs. The load module includes plural inputs coupled to the plural Class 2 cables, an output coupled to a Class 1 load, and circuitry coupled to the plural inputs and the output. The circuitry combines the plurality of Class 2 channels received via the plural inputs into a single Class 1 channel and conducts the single Class 1 channel to the output.

The invention discloses an adaptive fault clearing scheme for an MMC VSC-HVDC grid based on source-grid coordination. A grid-side circuit breaker topology is disposed at each end of each DC line of the MMC VSC-HVDC grid to coordinate with a source-side control strategy when a fault occurs to the DC line so as to isolate the fault together. When a system runs stably, the voltage regulation controller does not actuate, after the fault occurs, the voltage regulation controller is started, and the output voltage regulation coefficient decreases, so that voltage at outlets of the converters drops accordingly, and coordinates with voltage of the pre-charging capacitor of the grid-side circuit breaker topology to realize fault isolation based on source-grid coordination. The adaptive fault clearing scheme provided by the invention greatly improves the speed of fault isolation.

Systems, methods, techniques and apparatuses of high current protection are disclosed. One exemplary embodiment is a power system comprising a solid-state circuit breaker including a solid-state switching device, an energy dissipation branch, an assistive branch, and a controller. The energy dissipation branch is coupled in parallel with the solid-state switching device and includes an energy dissipation device. The assistive branch is coupled in parallel with the solid-state switching device and includes a resistor, an inductor, and a galvanic isolation switching device coupled together in series. The controller is configured to determine the solid-state circuit breaker is conducting a high magnitude current, select a continuous current limiting mode or an intermittent current limiting mode, and operate the solid-state switching device based on the selected current limiting mode.

A system for overvoltage protection in an electric aircraft, and a method for its use. The system includes an energy storage element, an overvoltage protection device, a ground conductor, at least a current conductor, at least a sensor, and a controller. The overvoltage protection device is configured to control transmission of electrical power through the connector. The at least a sensor is configured to detect an output voltage of the connector. The controller is communicatively connected to the at least a sensor. The controller is configured to determine an overvoltage output, and activate the over based on detection of the overvoltage output.

The invention discloses an adaptive fault clearing scheme for an MMC VSC-HVDC grid based on source-grid coordination. A grid-side circuit breaker topology is disposed at each end of each DC line of the MMC VSC-HVDC grid to coordinate with a source-side control strategy when a fault occurs to the DC line so as to isolate the fault together. When a system runs stably, the voltage regulation controller does not actuate, after the fault occurs, the voltage regulation controller is started, and the output voltage regulation coefficient decreases, so that voltage at outlets of the converters drops accordingly, and coordinates with voltage of the pre-charging capacitor of the grid-side circuit breaker topology to realize fault isolation based on source-grid coordination. The adaptive fault clearing scheme provided by the invention greatly improves the speed of fault isolation.

Provided are a protection circuit and a photovoltaic system capable of irreversibly interrupting a current path of photovoltaic units such as solar cells by a signal in an emergency such as a fire. The protection circuit includes: a photovoltaic units 26, a protection element 2 provided on a current path of the photovoltaic units 26, and a switch 3 for activating the protection element 2, wherein the protection element 2 irreversibly interrupts the current path of the photovoltaic units 26.

A direct current electrical network includes nodes linked by branches and protection elements mounted on the branches, each protection element includes a central processing unit, a current sensor, a current limiter device and a circuit breaking device, wherein: the current sensor is configured to determine the direction of the current in the branch relative to the node with which said protection element is associated; the central processing unit is configured to select, as a function of the direction of the current, a selected threshold value as one of a first value or a second threshold value greater than the first threshold value in absolute value, and to compare the value of the intensity of the current to the selected threshold value; and the current limiter device is bidirectional and is configured to limit the current passing through the branch to the selected threshold value.

Electrical devices are connected to a DC voltage power supply grid being connected to a power source and having a supply voltage. Protection devices protect the electrical devices against an unintentional overcurrent sensed by a sensor unit. The protection devices disconnect the electrical devices from the DC voltage power supply grid when an overcurrent is detected. A pulse circuit having a capacitor with a semiconductor switching element connected in series with the capacitor is connected to respective inputs of the protection devices and supplies an amount of electric charge when a voltage dip occurs, wherein the amount of supplied electric charge is determined based on the detected overcurrent and a predetermined time period.

Provided are a protection circuit and a photovoltaic system capable of irreversibly interrupting a current path of photovoltaic units such as solar cells by a signal in an emergency such as a fire. The protection circuit includes: a photovoltaic units 26, a protection element 2 provided on a current path of the photovoltaic units 26, and a switch 3 for activating the protection element 2, wherein the protection element 2 irreversibly interrupts the current path of the photovoltaic units 26.

A solid state circuit breaker apparatus includes a solid state switch, a current sensor, and a control circuit. The control circuit is programmed to operate the solid state switch by, in response to receipt of a signal from the current sensor indicating that an overcurrent condition exists: (i) using pulse width modulation to generate a set of control pulses; and (ii) using the control pulses to trigger the solid state switch to open and close in a pattern that corresponds to the control pulses, and thus limit an amount of let-through current that the solid state switch may pass to a load. The amount of let-through current that the solid state switch may pass to the load may be, for example, a threshold level above which the overcurrent condition will exist.