Abstract: An isolated resonant converter is provided, including a first side circuit, a second side circuit, and a resonant tank circuit. The resonant tank circuit includes a first resonant capacitor, a second resonant capacitor, and an integrated magnetic element. The integrated magnetic element includes a first side winding, a second side winding and a spaced groove provided between the first side winding and the second side winding. And the spaced groove stores leakage inductance energy, thereby forming at least part of resonant inductance required. Therefore, a number and volume of magnetic elements in the resonant converter are reduced.

Abstract: A power module, including: a first conductor, disposed at a first reference plane; a second conductor, disposed at a second reference plane, wherein projections of the first and second conductors on the first reference plane have a first overlap area; a third conductor, disposed at a third reference plane; a plurality of first switches and a plurality of second switches, wherein at least one of the first switches and at least one of the second switches that are located on a left side are alternatively disposed, at least one of the first switches and at least one of the second switches that are located on a right side are alternately disposed, and the left side and the right side of the first overlap area are oppositely disposed. Heat sources of the power module are evenly distributed and its parasitic inductance is low.

Abstract: Disclosed are a control method and control system for a modular multilevel converter and a power transmission system. The control method includes calculating an actual capacitor voltage of the sub-module; calculating a reference capacitor voltage of the sub-module; dividing the plurality of sub-modules into a plurality of modules, reference capacitor voltages of the sub-modules in the same module are the same, and reference capacitor voltages of the sub-modules from different modules are different; sorting in the module to obtain a first voltage sequence; sorting among different modules to obtain a second voltage sequence; and determining the sub-modules to be switched on or switched off according to charging and discharging states of the sub-module, the first voltage sequence and the second voltage sequence, until an actual level of the bridge arm is consistent with a desired level, wherein the desired level changes using a first preset value as a step.

Abstract: The present invention discloses a flying capacitor converter, a short circuit current suppression circuit for the same and an energy storage system. The flying capacitor converter comprises a controller, and has a high voltage side connected to a first power source and a low voltage side connected to a second power source. The short circuit current suppression circuit comprises: at least one current detection unit connected to the low voltage side and/or the high voltage side of the flying capacitor converter; and at least one switch set connected in series to the high voltage side and/or the low voltage side of the flying capacitor converter, wherein the controller controls the switch set to cut off a connection between the flying capacitor converter and the first power source and/or between the flying capacitor converter and the second power source, when the current detection unit detects a short circuit.

Abstract: A wind power converting device includes a plurality of grid-side converters, a plurality of generator-side converters and a plurality of DC buses. The grid-side converters are connected with each other in series and electrically coupled to a power grid. The generator-side converters are connected with each other in series and electrically coupled to a generator device. The DC buses are electrically coupled between the grid-side converters and the generator-side converters. The DC buses include a positive DC bus, a negative DC bus and at least one intermediate DC bus between the positive DC bus and the negative DC bus. A cross section area of a conductor of the intermediate DC bus is smaller than 30% of a cross section area of a conductor of the positive DC bus or smaller than 30% of a cross section area of a conductor of the negative DC bus.

Abstract: The invention provides a conversion circuit for converting an input voltage into an output voltage, including: a first full-wave rectifier circuit including a first branch and a second branch connected in parallel, each including a winding and a rectifier switch connected in series to form a midpoint; a first switch branch including a first switch and a second switch connected in series to form a first connection node; and a first resonant unit connected between the first connection node and a midpoint of the second branch, wherein the first resonant unit is not connected in series to the windings of the transformer. The conversion circuit of the invention improves conversion efficiency while maintaining smaller voltage stress on switches.

Abstract: Disclosed are a control method and control system for a modular multilevel converter and a power transmission system. The control method comprises: calculating an actual capacitor voltage and a reference capacitor voltage of the sub-module; dividing the plurality of sub-modules into a plurality of modules, wherein reference capacitor voltages of the sub-modules in the same module are the same, and reference capacitor voltages of the sub-modules among different modules are different; obtaining a first voltage sequence and a second voltage sequence; and determining the sub-modules to be switched on or switched off according to charging and discharging states of the sub-modules, the first voltage sequence and the second voltage sequence, until an actual level of the bridge arm is consistent with a desired level, wherein the desired level changes taking an insert value selected from a combination of one or more elements in a collection {INTERk} as a step.

Abstract: The present disclosure relates to the field of power electronics technology, and proposes a power module, including: a case and an isolating part disposed in the case; a first air duct and a second air duct stacked to each other, separated by the isolating part, and penetrated in a front-to-rear direction in the case; a high-voltage power unit; a low-voltage power unit; and a transformer, including a high-voltage portion and a low-voltage portion, wherein the high-voltage portion includes a first magnetic core and a high-voltage coil disposed on the first magnetic core, and the low-voltage portion includes a second magnetic core and a low-voltage coil disposed on the second magnetic core, wherein the high-voltage power unit and the high-voltage portion are disposed in the first air duct, and the low-voltage power unit and the low-voltage portion are disposed in the second air duct.

Abstract: It is disclosed an insulation impedance detection circuit and detection method of a photovoltaic inverter system. The photovoltaic inverter system includes one or more input circuits and an inverter circuit, each of the input circuit electrically coupled to the inverter circuit through a positive bus and a negative bus, with a first equivalent impedance Rp between the positive bus and a protective earth point and a second equivalent impedance Rn between the negative bus and the protective earth point. The detection circuit includes: a bus voltage sampling circuit coupled to the positive bus and the negative bus for generating a first bus voltage and a second bus voltage; a protective earth voltage sampling circuit coupled to the protective earth point for generating a first protective earth voltage and a second protective earth voltage; and a controller for calculating an equivalent insulation impedance.

Abstract: The present disclosure provides a semiconductor chip including a functional area, a first end, a second end, a third end, and a connecting portion. The functional area has first and second sides opposite to each other. The first end is disposed on the first side and the third end is disposed on the first side, wherein the semiconductor chip is switched on or off according to the drive signal received between the third end and the first end, and the connecting portion is disposed on the first side of the functional area and connected to the first end and the third end, wherein when the temperature rises above the a first temperature, the connecting portion is in a conductive state, and when the temperature drops to be not higher than a third temperature, the connecting portion is in an insulated state.

Abstract: The present disclosure provides a heat dissipation structure for a magnetic component and a magnetic component having the same. The magnetic component includes a plurality of heat dissipation pins, which are disposed on the winding of the magnetic component, wherein the magnetic component has one or more windings. The heat dissipation structure includes a circuit board on which a plurality of heat dissipation channels are disposed, and the heat dissipation pins of the windings are in contact with the heat dissipation channels; a plurality of heat conduction portions are disposed correspondingly under the heat dissipation channels of the circuit board; a heat conduction layer is arranged under the heat conduction portions and contacts with the heat conduction portions; and a heat dissipation layer is arranged under the heat conduction layer and contacts with the heat conduction layer.

Abstract: A modular power supply system includes: a main controller, configured to output a main control signal; N local controllers, wherein each of the local controllers is configured to receive the main control signal to output at least one local control signal; and N power units, in one-to-one correspondence with the N local controllers, wherein each of the power units includes a first end and a second end, and the second end of each of the power units is connected to the first end of an adjacent one of the power units, each of the power units is configured to include M power converters, each of the power converters is configured to operate according to the local control signal, wherein the same local control signal controls the power semiconductor switches at an identical position in at least two of the M power converters to be simultaneously turned on and off.

Abstract: A control method for a power factor correction circuit is disclosed. The power factor correction circuit includes a first bridge arm, a second bridge arm, an output capacitor and an active clamp unit. The control method includes steps of providing a first driving waveform to control a main switch, providing a second driving waveform to control an auxiliary switch, and providing a third driving signal to control a fifth switch. A first delay time is between the turning-off time point of the third driving signal and the turning-on time point of the first driving waveform, a second delay time is between the turning-on time point of the first driving waveform and the turning-off time point of the second driving waveform, and a third delay time is between the turning-off time point of the second driving waveform and the turning-on time point of the third driving signal.

Abstract: A magnetic element, a power module and a power conversion system are provided. The magnetic element includes a main body, a plurality of first magnetic posts, a first common magnetic post and a second magnetic post. A first lateral edge and a second lateral edge of the main body are opposite to each other and extended along a first direction. A third lateral edge and a fourth lateral edge of the main body are opposite to each other and extended along a second direction. The plurality of first magnetic posts are disposed on the main body and arranged along the first direction. The first common magnetic post is disposed on the main body and located at the first magnetic posts. The second magnetic post is disposed on the main body and located at the first common magnetic post.

Abstract: A three-phase power supply system includes three phase branches forming a delta connection. Each of the phase branches includes at least one power conversion cell of at least two stages. The at least one power conversion cell of each of the phase branches is connected in parallel to the at least one power conversion cell of the respective other two phase branches. When one of the phase branches stops operating, the other two phase branches keep operating, and three phase current of the three-phase power supply system can be balanced by regulating active powers and reactive powers of the other two phase branches. Through the invention, when one of the phase branches stops operating, the other two phase branches may keep operating, and three phase current of the three-phase power supply system are balanced.

Abstract: A DC-side soft switching device for a converter includes a battery, a bus capacitor, a first relay switch, a first resistor, a second relay switch, a second resistor, and a third resistor. The first relay switch is arranged between an anode of the battery and the bus capacitor. The first resistor is electrically connected in parallel to the first relay switch. The second relay switch is arranged between a cathode of the battery and the bus capacitor. The second resistor is electrically connected in parallel to the second relay switch. The third resistor is electrically connected in parallel to the bus capacitor.

Abstract: The present application provides a method for pre-charging a cascade converter and a cascade converter. The cascade converter includes a main transformer, multiple power units, a control unit and a precharge unit. Power units connected with the precharge unit are a first power unit group, and other power units are a second power unit group. The control unit controls first switch set in the precharge unit to be turned on, and low-voltage AC power supply in the precharge unit performs pre-charging for a bus capacitor through an inverter circuit in the first power unit group. When a voltage of the bus capacitor reaches a first voltage threshold, the control unit controls a rectifier circuit in the first power unit group to work to magnetize the main transformer, thereby performing pre-charging for bus capacitors in the second power unit group.

Abstract: The present disclosure provides a transformer module and a power module, wherein the transformer module comprises: a magnetic core, a first metal winding and a second metal winding. A first wiring layer, a first insulating layer and a second wiring layer are sequentially disposed on the magnetic core from the outside to the inside; the first metal winding is formed on the first wiring layer and winded around the magnetic core in a foil structure; the first insulating layer is at least partially covered by the first metal winding; a second metal winding is formed on the second wiring layer and winded around the magnetic core in a foil structure, wherein the second metal winding is at least partially covered by the first insulating layer, and is at least partially covered by the first metal winding.

Abstract: The disclosure provides a multilevel port under-voltage protection circuit with flying capacitor, comprising: a first circuit unit having first to fourth power switches sequentially connected in series, wherein the first circuit unit is arranged a positive terminal and a negative terminal of a DC input port and each of the switches can tolerate a reverse current; a first flying capacitor having a first terminal connected to the common node of the first power switch and the second power switch in series, and a second terminal connected to the common node of the third power switch and the fourth power switch in series; and a first shunt element connected in antiparallel to the first power switch or the fourth power switch, wherein a pulse peak current tolerated by the first shunt element is greater than the reverse current tolerated by the first power switch or the fourth power switch.

Abstract: Disclosed are three-phase system and distributed control method. The three-phase system comprises three-phase circuits, of which each phase circuit including at least one power conversion cell; and at least three phase controllers for controlling each phase circuit, respectively, each phase controller including a communication interface through which the at least three phase controllers are in communications connection with each other; wherein the phase controllers of each phase circuit is configured for regulating bridge arm voltages of the at least one power conversion cell in the phase circuit by receiving signals sent from the phase controllers of other two phase circuits through the communication interface. The three-phase system and the distributed control method of the invention solve problems of balance of three-phase current and stabilization of three-phase DC voltages by coordination among the three phases.