A power converter can include a first line, a second line, a capacitor line disposed between the first line and the second line, a first capacitor and a second capacitor connected to the capacitor line in series between the first line and the second line, a midpoint line connected to a midpoint between the first capacitor and the second capacitor, and a protection circuit disposed between the first capacitor and the second capacitor and configured to provide protection to one or more portions of the power converter.

A vehicle mounted electrical power converter includes: a heatsink; a circuit board placed on or above the heatsink; a power semiconductor device mounted on or above the circuit board; a control board support base that is placed on and/or above the circuit board and that supports a control board; and a heat transfer member being interposed between the power semiconductor device and the control board support base and thermally coupling between the power semiconductor device and the control board support base.

A vehicle mounted electrical power converter includes: a heatsink; a circuit board placed on or above the heatsink; a power semiconductor device mounted on or above the circuit board; a control board support base that is placed on and/or above the circuit board and that supports a control board; and a heat transfer member being interposed between the power semiconductor device and the control board support base and thermally coupling between the power semiconductor device and the control board support base.

Provided is a switch driving apparatus including a controller configured to individually control a first switch element and a second switch element included in a bidirectional switch, in which, when the controller stops on/off drive of the bidirectional switch, the controller turns off both the first switch element and the second switch element and then temporarily turns on one of the first switch element and the second switch element for a predetermined on time period.

A method to control storage into and depletion from multiple energy storage devices. The method enables an operative connection between the energy storage devices and respective power converters. The energy storage devices are connectible across respective first terminals of the power converters. At the second terminals of the power converter, a common reference is set which may be a current reference or a voltage reference. An energy storage fraction is determined respectively for the energy storage devices. A voltage conversion ratio is maintained individually based on the energy storage fraction. The energy storage devices are stored individually with multiple variable rates of energy storage through the first terminals. The energy storage is complete for the energy storage devices substantially at a common end time responsive to the common reference.

A method to control storage into and depletion from multiple energy storage devices. The method enables an operative connection between the energy storage devices and respective power converters. The energy storage devices are connectible across respective first terminals of the power converters. At the second terminals of the power converter, a common reference is set which may be a current reference or a voltage reference. An energy storage fraction is determined respectively for the energy storage devices. A voltage conversion ratio is maintained individually based on the energy storage fraction. The energy storage devices are stored individually with multiple variable rates of energy storage through the first terminals. The energy storage is complete for the energy storage devices substantially at a common end time responsive to the common reference.

A method of monitoring condition of a modular multilevel converter, wherein the modular multilevel converter includes submodules having a capacitor and controllable switches. The method including selecting a submodule, controlling the controllable switches of the selected submodule to form a current path through the submodule by controlling at least one controllable switch to a conducting state and at least one controllable switch to a blocking state, disconnecting the voltage of the capacitor of the selected submodule from the submodule, performing measurements on at least one controllable switch that was controlled to a blocking state.

A method of monitoring condition of a modular multilevel converter, wherein the modular multilevel converter includes submodules having a capacitor and controllable switches. The method including selecting a submodule, controlling the controllable switches of the selected submodule to form a current path through the submodule by controlling at least one controllable switch to a conducting state and at least one controllable switch to a blocking state, disconnecting the voltage of the capacitor of the selected submodule from the submodule, performing measurements on at least one controllable switch that was controlled to a blocking state.

A method involves controlling, for a duration of a first modulation period, a first average off-time of a main switch of a power converter such that the first average off-time of the main switch corresponds to a first intermediate valley number of multiple intermediate valley numbers, an average of the intermediate valley numbers corresponding to a target number of valleys of a resonant waveform at a drain node of the main switch. A second intermediate valley number of the intermediate valley numbers is selected upon expiration of the first modulation period. A difference of the second intermediate valley number and the first intermediate valley number is equal to a fractional valley number offset. A second average off-time of the main switch is controlled for a duration of a second modulation period such that the second average off-time of the main switch corresponds to the second intermediate valley number.

A power conversion device and a press apparatus capable of preventing an excessive current in a DC-link capacitor are provided. The power conversion device 10 includes a voltage-doubling rectifier circuit 12. In the voltage-doubling rectifier circuit 12, in a voltage-doubling rectification mode, a common connection node Nc between two capacitors 102a and 102b is connected to a predetermined node. A current detector circuit 107 detects a switching current (IL) flowing in the switching elements SW1 and SW2, and a current detector circuit 108 detects a load current Ild of a load 15. In a mode switching period from a full-wave rectification mode to a voltage-doubling rectification mode, a controller circuit 110 controls the switching of the switching elements SW1 and SW2, based on the switching current (IL) and the load current Ild.