An IGBT short-circuit detection and protection circuit, comprising: a driving unit, the output end thereof outputting a PWM driving signal and being connected to gate ends of a first IGBT (IGBT1) and a second IGBT (IGBT2), so as to simultaneously control the turning ON/OFF of the first IGBT and the second IGBT; a comparing unit, comprising a threshold pin and a detection pin (Vdesat), the threshold pin being connected to a threshold voltage, the detection pin being connected by means of a first diode (D1) and a second diode (D3) to collectors (C) of the first IGBT and the second IGBT, respectively, the detection pin supplying a detection current to the first diode and the second diode, cathodes of the first diode and the second diode being connected to the collectors of the first IGBT and the second IGBT, respectively; when the voltage at the detection pin is higher than the threshold voltage, the driving unit controlling the first IGBT and the second IGBT to be turned off. The IGBT short-circuit detection protection circuit achieves bidirectional short-circuit protection of two IGBTs in inverse series connection, without requiring an additional protection circuit.

The present invention relates to switching element protection of a BLDC motor, such as used with a power tool. The present invention checks each switching element of a power stage individually for a short circuit when a trigger of the tool is actuated. Each switching element is turned ON for a period of time (such as 1-5 microseconds, for example), current flowing through the half-bridge or the full power stage is measured, and that switching element is turned OFF. When the current is greater than or equal to a threshold (such as 5 A, for example), the controller stops and indicates a fault condition. By testing each switching element in order, the controller is able to determine whether the shorted switching element is the opposite one in the half-bridge being tested.

An adaptive electrical power distribution panel receives electrical power from at least an alternative power source other than a utility electric grid, and selectively outputs power to a plurality of branch circuits, appliances, or devices. An internal or remote controller monitors conditions. In response to the monitored conditions, the controller algorithmically divides the plurality of branch circuits, appliances, or devices into a first group to receive power from the alternative power source and a second group to not receive power from the alternative power source, and breaks electrical connections between the alternative power source and the second group. The monitored conditions may include operating parameters the grid; an instantaneous or average individual current flow; and a charge state of storage batteries. The division into groups may also be in response to stored information, such as a priority of, or history of current usage by, each branch circuit, appliance, or device.

A method for switching off power semiconductor switches in a bridge circuit having first through sixth power semiconductor switches. The method includes a switch-off process for establishing a final switch configuration in which all power semiconductor switches in the bridge circuit are in a switched-off state. Over the course of the switch-off process, a switch configuration is established in which the fifth power semiconductor switch and the sixth power semiconductor switch are concurrently in a switched-on state, while the first power semiconductor switch and the fourth power semiconductor switch are in a switched-off state. Also disclosed is a bridge circuit having a control circuit configured to carry out such a method. In addition, an inverter that includes at least one bridge circuit of this type is also provided.

Disclosed are an apparatus and a method for predicting a fault state of an inverter. The apparatus for predicting a fault state of an inverter includes: an inverter converting DC power into AC power; a switching element provided in the inverter; and a controller extracting a fault sign factor based on an output signal output from the inverter and predicting a fault of the switching element based on the fault sign factor.

A short-circuit detector includes: a first Rogowski coil configured to generate a first detection signal in accordance with a current that flows through a first arm due to a short circuit in a load; a second Rogowski coil configured to generate a second detection signal in accordance with a current that flows through the first arm due to a short circuit in the first arm or a second arm; a load short-circuit detection circuit configured to detect the short circuit in the load, based on the first detection signal; an arm short-circuit detection circuit configured to detect the short circuit in the first arm or the second arm, based on the second detection signal; and a short-circuit detection circuit configured to detect a short-circuit, based on: an output signal output from the load short-circuit detection circuit; and an output signal output from the arm short-circuit detection circuit.

An electrical bypass apparatus is provided, which comprises first and second terminals for connection across an electrical component; an electrically-triggered bypass switch being switchable to form a short circuit across the first and second terminals; and a first control circuit connected between the first and second terminals. The first control circuit includes mutually coupled first and second windings, the first winding being isolated from the second winding. The first control circuit is configured to inhibit a current flowing between the first and second terminals from flowing through the first winding when a normal operating voltage is present across the first and second terminals; and to permit a current to flow between the first and second terminals and through the first winding when an overvoltage is present across the first and second terminals and thereby induce a current pulse in the second winding.

Includes: a first offset voltage computing section, which is configured to compute, when the three-phase voltage commands are determined as a maximum phase, an intermediate phase, and a minimum phase in descending order, a first offset voltage by subtracting a first DC voltage calculated by multiplying the DC voltage by a first constant from the maximum phase, and to set the first offset voltage to zero when a sign of the first offset voltage is negative; a corrected three-phase voltage command computing section, which is configured to subtract the first offset voltage from each phase of the three-phase voltage commands to output corrected three-phase voltage commands; and an inverter, which is configured to output the three-phase voltages based on the corrected three-phase voltage commands.

An adaptive electrical power distribution panel receives electrical power from at least an alternative power source other than a utility electric grid, and selectively outputs power to a plurality of branch circuits, appliances, or devices. An internal or remote controller monitors conditions. In response to the monitored conditions, the controller algorithmically divides the plurality of branch circuits, appliances, or devices into a first group to receive power from the alternative power source and a second group to not receive power from the alternative power source, and breaks electrical connections between the alternative power source and the second group. The monitored conditions may include operating parameters the grid; an instantaneous or average individual current flow; and a charge state of storage batteries. The division into groups may also be in response to stored information, such as a priority of, or history of current usage by, each branch circuit, appliance, or device.

A breaker apparatus and an inverter system are configured to disconnect an electrical connection when a fault occurs in a protected circuit. The breaker apparatus is connected in series in a protected circuit, and is configured to disconnect the electrical connection when a fault occurs in the protected circuit. The breaker apparatus includes a first branch, and a second branch. The first branch includes an overcurrent-automatic-disconnection unit and a first current limiting unit that are connected in series, where the overcurrent-automatic-disconnection unit is configured to be automatically disconnected when a current flowing through the overcurrent-automatic-disconnection unit exceeds a breaking current threshold. The a second branch is configured to be open or closed under control of the controller. The controller is configured to control the first controllable switch unit to be closed when the protected circuit operates normally, and control the first controllable switch unit to be open when a fault occurs in the protected circuit.