A method for controlling a three-level brake chopper and a three-level brake chopper including, a first controllable semiconductor switch connected between a positive direct current pole and a first connection point, a second controllable semiconductor switch connected between the first connection point and a neutral direct current pole, a third controllable semiconductor switch connected between the neutral direct current pole and a second connection point, a fourth controllable semiconductor switch connected between the second connection point and a negative direct current pole, resistance means connected between the first connection point and the second connection point, and control means configured to control the second controllable semiconductor switch and the third controllable semiconductor switch into a conducting state in response to detecting a fault in the resistance means.

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 ground fault detection method for a power converter is provided, including: measuring, by a voltage sensor, a first voltage and a second voltage respectively, and converting the first voltage and the second voltage into a first digital voltage signal and a second digital voltage signal; receiving, by a controller, the first digital voltage signal and the second digital voltage signal, extracting a corresponding feature quantity of the first voltage and a corresponding feature quantity of the second voltage according to the first digital voltage signal and the second digital voltage signal; and further determining a type of the ground fault of the power converter and locating a ground fault; and when the power converter has a ground fault, shutting down the power converter.

The present disclosure relates to a clothes treating apparatus including a drum, a door to open and close the drum, an opening/closing switch to output a signal in response to opening or closing of the drum by the door, a motor to rotate the drum, a controller to generate a control command for controlling a rotational speed of the motor, a driving device including an inverter to convert power applied to the motor and an inverter driver to output a control signal of the inverter in response to the generated control command, and a protection switch connected between the opening/closing switch and the inverter driver to be turned on or off by the signal output by the opening/closing switch, wherein the inverter driver turns off the inverter when a voltage applied by the protection switch is less than or equal to a reference voltage.

The present invention discloses a self-test leakage protector with a timing function, comprising a leakage protection module, a timer module, a DC power supply module, and a DC power supply module control switch, wherein the DC power supply module control switch is connected between the DC power supply module and the leakage protection module, or between input AC power and the DC power supply module that supplies power to the leakage protection module, and is in an off state under a standby condition; according to a timing function requirement, the timer sends a signal of turning off or turning on the DC control switch; and when the turning-on signal is sent, the switch is closed, such that the leakage protection module is powered on for power-on reset, followed by a self-test of a leakage function, and if the self-test is passed, power is supplied to a load, and the self-test is carried out every time before power is supplied to the load. In the invention, the timing function of the timer is integrated in the self-test leakage protector capable of self testing, so the leakage protector is a separate product having a timing function with high safety, low standby power consumption and a low cost.

In an installation including a stored energy source and an electric motor which can be fed by an inverter, and a method for operating an installation, the stored energy source forms an electrical series circuit with a first fuse and further fuse(s). A controllable contact, e.g., a switch, a contactor, etc., is connected in parallel to the further fuse, or a respective controllable contact, e.g., a switch, a contactor, etc., is connected in parallel to each of the further fuses. The series circuit feeds the DC-voltage-side connection of the inverter, and a device for detecting the voltage applied to the series circuit is connected to control electronics which generate a control signal for the contact or control signals for the controllable contacts. For example, the respective contact is opened when the voltage falls below a respective voltage threshold.

In an installation including a stored energy source and an electric motor which can be fed by an inverter, and a method for operating an installation, the stored energy source forms an electrical series circuit with a first fuse and further fuse(s). A controllable contact, e.g., a switch, a contactor, etc., is connected in parallel to the further fuse, or a respective controllable contact, e.g., a switch, a contactor, etc., is connected in parallel to each of the further fuses. The series circuit feeds the DC-voltage-side connection of the inverter, and a device for detecting the voltage applied to the series circuit is connected to control electronics which generate a control signal for the contact or control signals for the controllable contacts. For example, the respective contact is opened when the voltage falls below a respective voltage threshold.

A protection device is disclosed which may comprise a first sensor, a first switch or a controller. The first sensor may be coupled to a first busbar of busbars and may be configured to measure a respective first electrical characteristic of the first busbar. The first switch may be connected between the first busbar and a reference terminal. The first switch may be configured to connect or disconnect the first busbar to and from the reference terminal. The controller may be coupled to the first sensor and to the first switch and may be configured to control the first switch to connect the first busbar to the reference terminal (e.g., based on the measurement of the first electrical characteristic indicating a change in the first electrical characteristic).

Exemplary electrical disconnects may include a housing defining a first access at a first end of the housing and a second access at a second end of the housing. The second access may extend vertically along a height of the housing beyond a vertical location of the first access. The electrical disconnects may include a busbar characterized by a first segment and a second segment. The first segment and the second segment may be coupled at a break section of the busbar. The first segment of the busbar may extend through the first access of the housing. The second segment of the busbar may extend through the second access of the housing. The electrical disconnects may include a pyrotechnic initiator disposed within the housing. The electrical disconnects may include a blade laterally aligned with the break section of the busbar. The electrical disconnects may include a plunger within which the blade is seated.