An energy storage device for storing energy for a stationary AC voltage grid includes a control device; and at least two switching units. Each switching unit includes multiple storage elements for storing a part of the energy, a converter having an AC voltage connection for connection to the AC voltage grid and a DC voltage connection, and a multiplexer switching device electrically connected with the DC voltage connection of the converter and with one of the storage elements via a respective storage connection. The multiplexer switching device is configured to select one of the storage connections in dependence on a selection signal generated by the control device and to electrically connect only the one storage connection selected by multiplexer switching device with the DC voltage connection of the converter. The control device is configured to control the converter of each of the at least two switching units so as to gradually reduce an energy flow between the AC voltage grid and a first one of the switching units and to correspondingly increase an energy flow between the DC voltage grid and at least one second one of the switching units until the energy flow between the AC voltage grid and the first switching unit is reduced to zero.

An energy storage device for storing energy for a stationary AC voltage grid includes a control device; and at least two switching units. Each switching unit includes multiple storage elements for storing a part of the energy, a converter having an AC voltage connection for connection to the AC voltage grid and a DC voltage connection, and a multiplexer switching device electrically connected with the DC voltage connection of the converter and with one of the storage elements via a respective storage connection. The multiplexer switching device is configured to select one of the storage connections in dependence on a selection signal generated by the control device and to electrically connect only the one storage connection selected by multiplexer switching device with the DC voltage connection of the converter. The control device is configured to control the converter of each of the at least two switching units so as to gradually reduce an energy flow between the AC voltage grid and a first one of the switching units and to correspondingly increase an energy flow between the DC voltage grid and at least one second one of the switching units until the energy flow between the AC voltage grid and the first switching unit is reduced to zero.

The present disclosure relates to power management apparatuses, systems, and methods utilizing a blocker stage. A power management apparatus may include a blocking string including a plurality of blocker stages connected in series, and each blocker stage may include at least one switch and at least one energy absorbing component. The apparatus may include a voltage/current monitor configured to monitor a power flow and generate current feedback and voltage feedback. The apparatus may further include a central controller coupled to the voltage/current monitor and configured to switch the energy absorbing components into or out of the power flow by synchronously turning the at least one switch of each of the plurality of blocker stages on or off based on the current feedback and the voltage feedback, where the plurality of blocker stages effectively act as a single blocking component.

An AC-to-DC converter includes a multi-resonant switching circuit including an AC-AC stage soft-switched LC network that converts a low-frequency low-amplitude alternating input voltage into a higher-frequency higher-amplitude alternating voltage and an AC-DC stage rectifying the higher-frequency higher-amplitude alternating voltage into a DC output voltage via a soft-switched diode. An AC-to-DC converter system includes at least two multi-resonant switching circuits that include at least two AC-AC stages and an AC-DC stage. A control system for the AC-to-DC converter includes at least two resonant gate drivers that each includes: one MOSFET gate configured to transmit a gate voltage signal to an AC-to-DC converter; an on/off logic module electrically coupled to the MOSFET gate; a resonant tank LC circuit electrically coupled to the on/off logic module; and a voltage bias module electrically coupled to the resonant tank LC circuit.

An electronic device, which includes an H-bridge circuit and a miniaturized transformer that is coupled to operate at VHF frequency, and a driver circuit for an n-type power transistor of the H-bridge circuit are disclosed. The driver circuit includes a first p-type transistor and an n-type transistor coupled between an upper rail and a lower rail, with an output taken between the drains of the first p-type transistor and the n-type transistor being coupled to a gate of the n-type power transistor. The driver circuit also includes a sample-and-hold capacitor coupled to capture a drain voltage for the first n-type power transistor on a first edge of a control signal for the first n-type power transistor and a comparator coupled to compare the captured drain voltage to a lower rail on a given edge of a clock signal and to provide a comparator value. The driver circuit also includes an up/down counter, which is coupled to receive the comparator value, to adjust a counter value responsive to receiving the comparator value and to output the counter value, and a first timing circuit that is coupled to receive the counter value and to send an adjustable pulse towards a gate of the first p-type transistor and a gate of the n-type transistor.

A multilevel converter includes a first and a second converter block series-connected between two DC terminals and a chopper circuit between the blocks. Each block includes a number of valve arm strings, each including an upper and a lower valve arm and a number of converter cells. A midpoint between the upper and lower arm of a string of the first block is connected to a corresponding primary AC terminal and a midpoint between the upper and lower arm of a corresponding string of the second block is connected to a corresponding secondary AC terminal. The chopper circuit comprises a power dissipating element in parallel with a circuit breaker.

A power system has a first control apparatus configured to generating a first command signal and a second command signal, to control the first converter on the basis of the first command signal, and to transmit the second command signal to a second control apparatus and the second control apparatus configured to control the second converter on the basis of the received second command signal. When it is requested that a state of each of the first and second converters is changed from a first state to a second state, the first control apparatus generates the first and second command signals so that the state of the second converter is changed to a third state in which both of the upper arm and the lower arm keep being in the OFF state, then the state of the first converter is changed from the first state to the second state, and then the state of the second converter is changed from the third state to the second state.

There is provided an electrical assembly for use in a power transmission network. The electrical assembly includes a converter including terminals for connection to an electrical network, where the first terminal is a DC terminal. The assembly also includes a DC power transmission medium connected to the DC terminal, and a circuit interruption device including switching element(s) and an energy absorption element, each switching element being switchable to divert a flow of current in the DC power transmission medium through the energy absorption element in order to reduce the flow of current in the DC power transmission medium; The assembly also includes a converter control unit programmed to operate the converter to control a DC voltage at the DC terminal in a leakage current reduction mode to control a voltage across the energy absorption element.

There is provided an electrical assembly for use in a power transmission network. The electrical assembly includes a converter including terminals for connection to an electrical network, where the first terminal is a DC terminal. The assembly also includes a DC power transmission medium connected to the DC terminal, and a circuit interruption device including switching element(s) and an energy absorption element, each switching element being switchable to divert a flow of current in the DC power transmission medium through the energy absorption element in order to reduce the flow of current in the DC power transmission medium; The assembly also includes a converter control unit programmed to operate the converter to control a DC voltage at the DC terminal in a leakage current reduction mode to control a voltage across the energy absorption element.

A bidirectional AC-to-DC and DC-to-AC circuit includes a first inductor-capacitor (LC) circuit connected to an AC power source, a transistor synchronized with the AC power source signal, a second LC circuit electrically connected to the synchronized transistor and the first inductor-capacitor circuit, a high-frequency switching transistor electrically connected to the second inductor-capacitor circuit and a direct current (DC) load, and a controller connected to the high-frequency switching transistor. The controller identifies an error between a measured DC output signal and a predetermined DC output signal that is applied to the DC load, and adjusts a duty cycle of a pulse width modulation (PWM) switching signal for the high-frequency transistor to reduce the identified error.