A damage predicting device of a power semiconductor switching element includes a resistor connected to a gate of the power semiconductor switching element, and control circuitry. The control circuitry compares a detection voltage matching a voltage generated between two ends of the resistor and a reference voltage, and predicts that predetermined damage has been accumulated in a gate insulating layer in the power semiconductor switching element when the detection voltage exceeds the reference voltage.

A device and a method for providing an electrical current to an electrical load is disclosed. In particular, the device comprises a memory storage device for storing a plurality of ideal voltage waveforms; an electronic controller arranged in data communication with the memory storage device, the electronic controller operable to select one of the plurality of ideal voltage waveforms to compute a reference voltage and a switching period based on a predetermined rule; and an electronic switch arranged to receive the switching period to switch the electronic switch between an on state and an off state, wherein the electrical current is calculated based on a function of the reference voltage and the switching period of the electronic switch.

A detection circuit is used to detect an input current of a switching power conversion circuit. The current detection circuit includes a current transform unit, a first unidirectional conduction component assembly, a flux reset circuit, a second unidirectional conduction component assembly, a first switch, a second switch, a control unit, and a detection unit. The current transform unit is coupled to a power switch of the switching power conversion circuit, and the first unidirectional conduction component assembly, the flux reset circuit, and the second unidirectional conduction component assembly are connected in parallel to the current transform unit. The first switch and the second switch are coupled to the first or second unidirectional conduction component assembly, and the control unit correspondingly controls the first switch and the second switch according to a first or second direction voltage of the input voltage.

A switching control circuit for controlling a power supply circuit that generates an output voltage from an alternating current (AC) voltage inputted thereto. The power supply circuit includes an inductor receiving a rectified voltage corresponding to the AC voltage, and a transistor controlling an inductor current flowing through the inductor. The switching control circuit controls switching of the transistor, and includes a first arithmetic circuit that calculates a first time period, from when the transistor is turned off to when the inductor current reaches a predetermined value, based on a first voltage corresponding to the rectified voltage, a second voltage corresponding to the output voltage, and the inductor current upon turning on of the transistor; and a drive circuit that causes the transistor to be on in a second time period corresponding to the second voltage, and causes the transistor to be off in the first time period.

Disclosed is a method and a control circuit. The method includes operating a buffer circuit (1) in a first operating mode or a second operating mode. Operating the buffer circuit (1) in the first operating mode includes buffering, by a capacitor parallel circuit including a first capacitor (11) and a second capacitor (12), power (Po) provided by a power source (3) and received by a load (4). Operating the buffer circuit (1) in the second operating mode includes supplying power to the load (4) by the second capacitor (12), and regulating a first voltage (Upn) across the second capacitor (12), wherein regulating the first voltage (Upn) comprises transferring charge from the first capacitor (11) to the second capacitor (12).

Embodiments of present disclosure relate to an apparatus and a method for controlling a delta-connected cascaded multilevel converter. The apparatus (100) for controlling a delta-connected cascaded multilevel converter (110) comprises: a converter controller (102) configured to: receive current signals indicating phase currents flowing through respective phase arms of the converter (110); determine a harmonic current signal indicating a circulating current of the converter (110) from the current signals; and generate, based on the determined harmonic current signal and a reference current signal, a harmonic voltage signal to cause an amplitude of the circulating current flowing through the phase arms of the converter (110) to be a predetermined amplitude.

An adapter device, including an AC connection including first AC contact and second AC contact; a DC connection including first DC contact and second DC contact; a first bridge branch including first switching device and second switching device, the first switching device and second switching device connected in series at a first bridge point, the first bridge point connected to first AC contact; a second bridge branch including third switching device and fourth switching device, third switching device and fourth switching device connected in series at a second bridge point, the second bridge point connected to second AC contact; and mode-setting device configured to predetermine a direction of power flow between AC connection and/or DC connection, first bridge branch and second bridge branch connected in parallel to the first DC contact and second DC contact, and different types of switching devices used as switching devices of a bridge branch.

A power factor correction circuit comprising: a global voltage input; and means for deriving a reference current from the global voltage; whereby the means for deriving the reference current comprises a leading phase admittance cancellation, LPAC, transfer function and a filter, whereby the reference current is derived from a sum of an output of the LPAC transfer function and an output of the filter.

A power factor correction circuit comprising: a global voltage input; and means for deriving a reference current from the global voltage; whereby the means for deriving the reference current comprises a digital leading phase admittance cancellation, DLPAC, transfer function and a filter, whereby the reference current is derived from a sum of an output of the DLPAC transfer function and an output of the filter, and further comprising means for compensating for delays in the DLPAC function.

A vehicle electrical system is equipped with a DC charging connection, a rechargeable battery, a first DC-DC converter and an electrical drive. The first DC-DC converter has a first side. This is connected to a connecting point via a first switch. The first DC-DC converter has a second side to which the electrical drive is connected. The second side is connected to the rechargeable battery via a second switch and via a connecting point or is connected to the rechargeable battery directly. The vehicle electrical system has a second DC-DC converter. This is connected to one side of the first switch.