Abstract:
A power converter is presented. The power converter includes at least one leg operatively coupled between a first bus and a second bus and includes a first string including a plurality of non-controllable semiconductor switches, a first node, a second node, and a third node, where the first node is coupled to a third bus, one or more second strings, where each of the one or more second strings includes at least one fully controllable semiconductor switch, and where one of the second strings is coupled between the first node and the third bus and another second string is coupled between the second node and the third node, and one or more third strings, where each of the one or more third strings includes at least one energy storage device and is coupled to the first string, the one or more second strings, or a combination thereof.
Abstract:
Embodiments of the present disclosure relate to a detection device for a circuit comprising a plurality of switch devices coupled in series. The detection device comprises a plurality of detecting circuits, wherein each detecting circuit is integrated with a gate driver of a corresponding switch device. Each detecting circuit comprises a voltage divider and a signal processor. The voltage divider is coupled in parallel with the corresponding switch device and comprises a plurality of voltage dividing components coupled in series. The signal processor is coupled with one of the voltage dividing components and configured to receive a divided voltage across the voltage dividing component and output an output signal indicating the voltage across the switch device. Embodiments of the present disclosure also relate to a system and method for protecting series-connected switch devices.
Abstract:
A protection circuit for a controllable switch comprising a control terminal, a first terminal, and a second terminal having a lower electric potential than the first terminal, the protection device comprising: an active clamping module, coupled between the first terminal and the control terminal of the controllable switch, configured to clamp a first voltage across the first terminal and the second terminal; and a damping module, coupled to an output of the active clamping module and configured to damp oscillations of a second voltage across the control terminal and the second terminal. Embodiments of the present disclosure also relate to a protection method for a controllable switch.
Abstract:
A power converter includes primary and secondary bridges, a transformer, and a controller configured to generate a switching mode map that correlates each of a plurality of switching modes to a respective set of value ranges of system parameters of the power converter. The sets of system parameter value ranges are contiguous and non-overlapping across the switching mode map, each of the plurality of switching modes includes gate trigger voltage timings for commuting at least one of the primary and secondary bridges. The controller is configured to obtain a plurality of measured system parameter values, select from the switching mode map one of the plurality of switching modes that correlates to the set of system parameter values containing the plurality of measured system parameter values, and adjust gate trigger voltage timings of at least one of the primary and secondary bridges, according to the selected switching mode.
Abstract:
A heat transfer assembly useful for dissipating heat from the heat emitting device is disclosed. The assembly includes a module inlet for receiving a coolant, at least one module having a first part with a recess to receive a portion of the heat emitting device, and a second part having a shaped cutout portion and a solid portion, where the second part allows a uniform compression of a seal component disposed on the first part. The first part and the second part are mechanically connected to each other; and a module outlet is used for discharging a heat absorbed coolant after absorbing heat from the heat emitting device, where the at least one module is connected to the module inlet and the module outlet. In another embodiment, multiple modules are configured in a symmetrical layout to provide a balanced flow of the coolant in the heat transfer assembly.
Abstract:
A converter assembly and method are provided. The converter assembly includes a galvanic isolation device, first switching devices, and second switching devices. The switching devices are conductively coupled with each other and with opposite sides of the isolation device. The first switching devices control conduction of an input voltage, and the second switching devices control conduction of electric power. The first switching devices are configured to switch between an open state and a closed state at frequencies that are faster than frequencies at which the second switching devices switch between the open state and the closed state to control a shape of a waveform of the electric power.
Abstract:
A system including an electromagnetic braking system that has an eddy current brake. The eddy current brake includes an electrically conductive surface coupled to a shaft of a generator system, wherein the eddy current brake is configured to induce an electromagnetic force on the electrically conductive surface when powered. The electromagnetic braking system further includes a supercapacitor coupled to the eddy current brake, wherein the supercapacitor is configured to discharge to power the eddy current brake for the duration of a ride through event of the generator system, and the supercapacitor is configured to supply a threshold current to the eddy current brake within approximately 100 ms of a start of the ride through event.
Abstract:
A method and system for a control power supply system is provided. The control power supply system includes a first conductor configured to carry a direct current (DC) electrical current from a source to a load, a second conductor configured to carry the DC electrical current from the load to the source, and an AC power source coupled to at least one of the first and the second conductors, the AC power source configured to superimpose a selectable relatively high frequency AC component onto the DC electrical current to generate a composite power signal.
Abstract:
A braking system includes a converter, a capacitor coupled to an output of the converter, a bridge coupled in parallel to the capacitor, and at least one inductor coupled to the bridge, an electrically conductive disc disposed proximate to the at least one inductor, and a switching unit controller for commanding the converter to convert a level of voltage supplied therefrom from a first voltage level to a second voltage level and thereby increase energy stored in the capacitor, and, upon receiving a brake command, commanding the bridge to ramp-up electrical current in the at least one inductor so as to induce an electromagnetic force on the electrically conductive disc.
Abstract:
A system for operating an on-load tap changer (OLTC) includes a plurality of legs that include mechanical switches. At least one leg switches from a first to a second tap of the OLTC on receipt of a tap change signal. At least one mechanical switch is activated to establish an electrical connection between one of the first and the second tap and a power terminal of the OLTC. Further, the system includes semiconductor switches that are parallel to the mechanical switches and when activated electrically couple one of the first and the second tap and the power terminal. The system includes a processing unit that selectively activates and deactivates the mechanical and semiconductor switches in such a way that electrical contact is maintained between at least one of the taps and the power terminal during the transition of at least one leg from the first tap to the second tap.