A crowbar module includes first and second electrical terminals, a module housing, and first and second crowbar units. The first crowbar unit is disposed in the module housing and includes a first thyristor electrically connected between the first and second electrical terminals. The second crowbar unit is disposed in the module housing and includes a second thyristor electrically connected between the first and second electrical terminals in electrical parallel with the first crowbar unit.

A safety shut-off system and method are provided for eliminating power to a load in the event of smoke detection. The system may comprise a device located at the appliance for detecting a signal from a smoke detector, and cutting power to the appliance only when the appliance is in use. The device may be synchronized with any standard smoke alarm signal to reduce the number of false positive shut-offs. The system may also comprise a smoke alarm hard-wired to a circuit breaker, for shutting off power to all appliances on a particular breaker upon receipt of a signal from the smoke alarm, and only when the appliances on the breaker are in use. The system may also have the ability to shut off one breaker, multiple breakers, or all breakers at different time increments to actively prevent and reduce the damages caused by fires.

A circuit breaker with pre-charging and current limiting functions, wherein the circuit breaker is configured for being provided in a power line connecting an electrical energy source and an electric network. The circuit breaker includes a short circuit protection unit including a first semiconductor switch, a precharge unit connected in parallel to the short circuit protection unit and including a second semiconductor switch, and a current limit unit connected in parallel to the short circuit protection unit and to the precharge unit, the current limit unit including a third semiconductor switch.

A circuit breaker includes an electromechanical switch, a current sensor, a voltage sensor, and a processor. The electromechanical switch is serially connected between a line input terminal and a load output terminal of the circuit breaker, and configured to be placed in a switched-closed state or a switched-open state. The current sensor is configured to sense a magnitude of current flowing in a path between the line input and load output terminals and generate a current sense signal. The voltage sensor is configured to sense a magnitude of voltage at a point on the path between the line input and load output terminals and generate a voltage sense signal. The processor is configured to receive and process the current sense signal and the voltage sense signal to determine operational status information of the circuit breaker and determine power usage information of a load connected to the load output terminal.

In electrical systems with DC-DC converters having synchronous rectification (SR) on the output stage, the input voltage can be monitored. When a potentially destructive transient occurs, the SR is rapidly turned on in a non-synchronous manner to “crowbar” the main power transformer. The resulting short circuit is reflected back to the DC input under current-limited pulse width modulation (PWM) control. In effect, the entire surge rating of the power train is applied to the potentially destructive input transient. The clamping capacity can be controlled accurately and is significantly more than what is available in prior art components and systems. When the input voltage is pulled down to safe levels, the clamp circuit disengages and the DC-DC converter returns to normal operation. DC output voltage regulation to the connected load is not maintained during this clamping event, but maintaining output voltage regulation during such destructive transients is not required.

A power management circuit has a power input terminal coupled to a power supply or a load, a power terminal configured to provide an output voltage, and a battery terminal coupled to a battery. The power management circuit further has a current limiting circuit, an over-current indication circuit and an over-current threshold selecting circuit. The current limiting circuit compares a current feedback signal indicative of an output current flowing out of the power terminal with a current threshold signal and generates a square wave signal. The over-current indication circuit generates an over-current indication signal based on the square wave signal. The over-current threshold selecting circuit selects a first over-current threshold voltage or a second over-current threshold voltage as an over-current threshold voltage based on the over-current indication signal, wherein the first over-current threshold voltage is higher than the second over-current threshold voltage.

The electronic circuit protector of the invention comprises a first semiconductor, a second semiconductor, a third semiconductor, a first diode, a second diode, a first resistor, a second resistor and a third resistor, constituting an application circuit with load overload or short circuit protection function, which avoids the damage caused by overload or short circuit at both terminals of the load.

A torque system includes a DC power device, a polyphase electric machine, a contactor pair, a power inverter module (PIM), and a controller. The PIM connects to the power device via the contactor pair and directly connects to the electric machine. The controller executes a method to control a fault response under a fault condition resulting in opening of the contactor pair and a polyphase short condition. The controller calculates a back EMF of the electric machine and transmits switching control signals to semiconductor switches of the PIM to transition from the polyphase short condition to a polyphase open condition only when the calculated back EMF is less than a calibrated value and a voltage rise on a DC side of the PIM is less than a calibrated voltage rise. A vehicle includes the DC power device, road wheels, electric machine, PIM, and controller.

Even when an overvoltage suppression circuit is not formed due to failure of an overvoltage suppression switch, overvoltage application to semiconductors and a filter capacitor is prevented. A control unit controls the overvoltage suppression circuit to short-circuit the filter capacitor when the voltage thereacross exceeds a predetermined value. Then when non-operation of the overvoltage suppression circuit is detected, the control unit opens an AC breaker and AC switch, and closes a charging switch. Thereafter, the control unit turns ON the converter element (or converter element) connecting to the filter capacitor terminal (or terminal) and a charging resistor, and turns ON converter element (or converter element) connecting to terminal (or terminal) of filter capacitor and connecting to the terminal of the transformer not connected to charging resistor.

A power conditioning circuit includes at least one power storage device having electrodes coupled for receiving power from a DC power source. At least one active current limit (ACL) circuit coupled to the electrodes of the power storage device is for limiting a maximum power output from the power storage device under fault conditions. A DC-to-DC converter has its inputs coupled to the ACL circuit. At least one crowbar circuit has a first terminal and a second terminal and a shorting device coupled to an output of the DC-to-DC converter for providing output terminals for the power conditioning circuit.