A voltage mode controller applied to short-circuited protection of a power converter includes gate control signal generation circuit and control circuit. The control circuit generates control signal to make the gate control signal generation circuit generate predetermined signal to power switch of the primary side of the power converter before the power converter starts up and when supply voltage is greater than first reference voltage, enables short-circuited protection after predetermined enabling period of the predetermined signal if detection voltage is less than second reference voltage during the predetermined enabling period. The short-circuited protection makes the power converter not start up, and after the power converter starts up, the short-circuited protection is enabled to turn off the power converter if the detection voltage is less than the second reference voltage for de-bounce time and compensation voltage is greater than third reference voltage.

In a switching power supply device including an overload protection circuit, when a load state turns into an overload state due to a decrease in an input voltage, an overload protection signal is activated in response to activation of an overload detection signal, and the overload protection signal is deactivated when an input low voltage detection signal is in an inactive state.

A determination circuit including a detection circuitry, a switch controller, and a determination circuitry. The detection circuitry is configured to detect that an overvoltage has occurred in an electric power supply path. The switch controller is configured to turn off a switch when the detection circuitry has detected that the overvoltage has occurred. The determination circuitry is configured to perform a determination operation including determining whether the overvoltage that has occurred is attributed to an electric power conversion circuit or a load, on a basis of one of or both a first voltage of a first path and a second voltage of a second path that are in a period in which the switch is off, the first path coupling the switch and the electric power conversion circuit in the electric power supply path, the second path coupling the switch and the load in the electric power supply path.

A drive device comprises a sensor for detecting a state of stress applied to a power transistor, a threshold voltage setting circuit for outputting a threshold voltage, an anomaly monitor circuit for determining whether or not a state of stress is abnormal by comparing a detected voltage of the sensor with the threshold voltage, and a control circuit for fixing the power transistor to either on or off when the state of stress is determined to be abnormal by the anomaly monitor circuit. When an operating mode is a test mode, the control circuit tests whether the anomaly monitor circuit determines the state of the stress is abnormal or not by switching a level of the threshold voltage set by the threshold voltage setting circuit so as to determine that a state of the stress applied to the power transistor is abnormal in the normally operating anomaly monitor circuit.

The present disclosure provides a method for controlling a surgical instrument. The method includes connecting a power assembly to a control circuit, wherein the power assembly is configured to provide a source voltage, energizing, by the power assembly, a voltage boost convertor circuit configured to provide a set voltage greater than the source voltage, and energizing, by the voltage boost convertor, one or more voltage convertors configured to provide one or more operating voltages to one or more circuit components.

An electric-power converter includes a plurality of direct-current power supplies, a plurality of power conversion circuits provided corresponding to the respective direct-current power supplies, an alternating-current power system configured to cause a plurality of alternating-current ends provided in the respective power conversion circuits to be directly connected in parallel through a parallel connection point, and to supply the alternating-current power output from the plurality of alternating-current ends to an alternating-current side through the parallel connection point, a plurality of grounding wires each configured to connect at least two of a plurality of direct-current negative buses between the plurality of direct-current power supplies and the plurality of power conversion circuits, to earth, and a plurality of diodes inserted in series into the respective grounding wires, and each including a cathode side connected to the corresponding direct-current negative bus and an anode side grounded.

The present disclosure provides a method for controlling a surgical instrument. The method includes connecting a power assembly to a control circuit, wherein the power assembly is configured to provide a source voltage, energizing, by the power assembly, a voltage boost convertor circuit configured to provide a set voltage greater than the source voltage, and energizing, by the voltage boost convertor, one or more voltage convertors configured to provide one or more operating voltages to one or more circuit components.

A high voltage protection system for saddle type vehicle detects the short circuiting of any wire. The high voltage protection system provides three different modules: a high voltage protection circuit, a fault collection circuit, and a fault detection circuit, working together to detect the short circuiting or voltage spike and disconnect the vehicle loads from the power supply to prevent an accident.

A Boost DC-DC switching converter, having a safety protection method for a short circuit to ground during normal Boost operations, is described. A short circuit protection mechanism, to be used at startup, is also described. A low current capability active clamp is activated, during a soft or hard short circuit condition, and an isolation switch is turned off. An input of the switching converter is isolated from an output of the switching converter, and the Boost switching converter is able to safely discharge high energy stored in its coil, with no external components and minimum extra silicon area.

An electrical power system including: an electrical power source, a power electronics converter, an electrical network, a current limiting diode and a controllable circuit interruption device, wherein: the current limiting diode is configured to limit a fault current passing between the electrical power source and the electrical network in a fault condition; and the controllable circuit interruption device is configured to interrupt the fault current in response to a determination that the electrical power system is in the fault condition.