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.

One general aspect includes methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for fault protection of a bidirectional wireless power transfer system. The method includes the actions of detecting, by control circuitry of a wireless power transfer device, a fault for the bidirectional wireless power transfer system. Identifying an operating personality of the wireless power transfer device and a hardware configuration of the wireless power transfer device. Identifying, in response to detecting the fault and based on the operating personality and the hardware configuration, protection operations for protecting the wireless power transfer device from the fault. Controlling operations of the wireless power transfer device according to the protection operations. Other implementations of this aspect include corresponding systems, circuitry, controllers, apparatus, and computer programs, configured to perform the actions of the methods, encoded on computer storage devices.

One general aspect includes methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for fault protection of a bidirectional wireless power transfer system. The method includes the actions of detecting, by control circuitry of a wireless power transfer device, a fault for the bidirectional wireless power transfer system. Identifying an operating personality of the wireless power transfer device and a hardware configuration of the wireless power transfer device. Identifying, in response to detecting the fault and based on the operating personality and the hardware configuration, protection operations for protecting the wireless power transfer device from the fault. Controlling operations of the wireless power transfer device according to the protection operations. Other implementations of this aspect include corresponding systems, circuitry, controllers, apparatus, and computer programs, configured to perform the actions of the methods, encoded on computer storage devices.

A method monitors an electrical assembly which contains a plurality of electrical coils connected in parallel. In the method, the difference in current between the current flowing through the coils and the mean value of the currents flowing through the coils is ascertained for each of the coils connected in parallel. The differences in current are used to identify when an inter-turn short circuit occurs in one of the coils.

A secondary circuit device including a secondary coil for transmitting and/or receiving magnetic energy of a magnetic field and converting the magnetic energy into electrical energy, a transmission unit for transmitting the electrical energy, a detection unit, and a damper circuit, wherein the magnetic field is generated by a primary coil of a primary circuit device; the transmission unit has an inlet for connecting the secondary coil; the transmission unit has an outlet for providing the electrical energy as voltage and/or current; the detection unit is connected to the inlet and/or the outlet of the energy transmission unit, in order to detect an overvoltage at the inlet and/or the outlet; and, when the overvoltage is detected, the detection unit is configured to influence the magnetic field in the secondary coil via the damper circuit such that a current jump and/or a voltage jump is brought about in the primary coil.

A wireless electric vehicle charging system comprises base-side equipment for generating a magnetic field and vehicle-side equipment for receiving energy via the magnetic field to supply power to a vehicle-driving battery. Monitoring circuitry monitors one or more of voltage, current, or phase associated with the base-side equipment and halts generation of the magnetic field in response to a change in the voltage, current, or phase associated with the operation of the base-side equipment that indicates a fault condition at the vehicle-side equipment, which may include a loss of power or disconnection of a battery. Based on detection of the change, the monitoring circuitry can halt generation of the magnetic field to prevent damage at the vehicle-side equipment.

There are provided a device for preventing an entire cabinet from being powered down, a cabinet, and a method for preventing an entire cabinet from being powered down. The device includes a diode and a first protection circuit. An anode of the diode is grounded, a cathode of the diode is connected to an external voltage supplying copper busbar via the first protection circuit, and the diode is connected in parallel with an external node. The first protection circuit is arranged to monitor a current flowing through the diode, and cut off a connection line between the diode and the voltage supplying copper busbar in a case that the current exceeds a preset fusing current threshold.

An arcing fault recognition unit is for an electric low-voltage circuit. In an embodiment, the arcing fault recognition unit includes at least one current sensor for periodically ascertaining electric current values in the electric circuit, the current sensor being connected to an analysis unit which is designed in such a way that an arcing fault recognition signal is output when a variation in the rate of current rise exceeds a first threshold value or drops below a second threshold value.

An arcing fault recognition unit is for an electric low-voltage circuit. In an embodiment, the arcing fault recognition unit includes at least one current sensor for periodically ascertaining electric current values in the electric circuit, the current sensor being connected to an analysis unit which is designed in such a way that an arcing fault recognition signal is output when a variation in the rate of current rise exceeds a first threshold value or drops below a second threshold value.

Provided is a method for monitoring DC electrical power. The method including determining a rate of change of the DC electrical power, determining whether the rate of change of the DC electrical power is greater than a predetermined threshold, when the rate of change of the DC electrical power is greater than the predetermined threshold, determining whether the rate of change of the DC electrical power is greater than the predetermined threshold for a predetermined period of time, and when the rate of change of the DC electrical power is greater than the predetermined threshold for the predetermined period of time, sending a signal indicating an interruption in the DC electrical power.