The present disclosure relates to an apparatus and a method for controlling an LLC resonance converter. The apparatus includes a converter connected to an input terminal, including a plurality of switching elements constituting a bridge circuit, and enabling a topology change in the form of a full bridge and a half bridge; and a controller detecting a charge measurement value of a battery being charged with a power transferred by the converter, and changing a topology of the converter based on the charge measurement value. Since battery charging is performed by changing the topology of the converter in accordance with the charge measurement value of the battery, the LLC resonance converter can be controlled at an optimized frequency, the efficiency is increased, and cost savings can be achieved.

A dual-input power conversion system includes a first primary side power network comprising a first hold-up capacitor, wherein the first primary side power network has inputs configured to be coupled to a first power source, and outputs coupled to a transformer, a second primary side power network comprising a second hold-up capacitor, wherein the second primary side power network has inputs configured to be coupled to a second power source, and outputs coupled to the transformer, and a secondary side power network having inputs coupled to a secondary side of the transformer, and outputs coupled to a load, wherein the first primary side power network and the second primary side power network are configured such that a voltage across one of the first hold-up capacitor and the second hold-up capacitor is maintained by a voltage reflected from the secondary side to a corresponding primary side.

A control circuit for an isolated power converter includes a first sensing circuit that senses a secondary side output voltage and produces a pulse wave modulation (PWM) signal having a duty cycle that is proportional to a value of the secondary side output voltage. The PWM is transferred across the converter isolation barrier to the primary side, and a primary side circuit receives the PWM signal and outputs a control signal. A controller determines the value of the secondary side output voltage from the control signal and uses the value to control primary side power switching devices of the isolated power converter to regulate the secondary side output voltage at a selected value.

A power converter includes: a switching transistor, a transformer, a control circuit; the control circuit is configured to determine a target voltage in a process that the switching transistor is driven to conduct; the target voltage can represent a voltage change of an input terminal of the switching transistor; when the target voltage starts to drop but is higher than a reference voltage, drive a control terminal of the switching transistor with a first driving current; when the target voltage decreases to be lower than the reference voltage, drive the switching transistor with a second driving current; the second driving current is higher than the first driving current; the switching transistor is driven by the first driving current for part or all of the time before entering the Miller plateau stage, and is driven by the second driving current after starting to enter the Miller plateau stage.

A cascaded power electronic transformer and a method for controlling the same are provided. The method includes: calculating electrical angles θ.sub.i1 and θ.sub.kps of an s.sup.th transformer and a compensation electrical angle θ.sub.j of a j.sup.th transformer; adding the compensation electrical angle θ.sub.j to the electrical angle θ.sub.kps of the j.sup.th transformer, to obtain a compensated electrical angle θ.sub.kps of the j.sup.th transformer; and calculating a square wave of a bridge arm voltage of each of the m primary converters and the r secondary converters of the s.sup.th transformer based on the electrical angle θ.sub.i1 and the electrical angle θ.sub.kps of the s.sup.th transformer after compensation.

Provided is a control circuit configured to control a switching element of a switching power source, the control circuit comprising: a first protection unit configured to stop a principal current flowing through the switching element when the principal current of the switching element has exceeded a first threshold value; and a second protection unit configured to stop the principal current of the switching element over a longer time period than the first protection unit when the principal current has exceeded a second threshold value larger than the first threshold value. The first protection unit may shorten a pulse width of a control pulse in one cycle of an oscillation signal, and the second protection unit may fix the switching element to the off-state over a plurality of cycles of the oscillation signal.

A multilink power converter with reduced winding voltage is disclosed, as well as various applications. In the disclosed embodiments, multiple primary switch modules have their inputs connected in series while using a single transformer winding connected in parallel to the modules' outputs through voltage blocking capacitors. Medium voltage solid-state transformers are presented, including three-phase power converters. Also presented are embodiments utilizing common mode inductors to equalize the currents of the high voltage modules.

There is provided a high frequency AC inverter comprising a DC-DC circuit, an output power circuit and a load circuit and a controller, the load circuit comprising a load circuit detector configured to detect the electrical parameters of the load circuit. The output power circuit comprises a DC to AC driver having a variable frequency output, a HFAC driver circuit comprising a resonant network and a transformer coupled to the HFAC driver circuit and the load circuit. The controller is configured to control the output frequency of the DC to AC driver and the output of the DC to DC circuit in response to the detected electrical parameters of the load circuit.

A power converter includes a switch control circuit for driving a high side switch of the power converter comprising the high side switch and a low side switch connected in series. The switch control circuit may have a first terminal for receiving an input signal, a second terminal used as a reference ground terminal of the switch control circuit, and a third terminal used as an output terminal to provide a driving signal, the switch control circuit can draw power from the input signal and may be configured to control a logic state of the driving signal based on a logic state of the input signal relative to a reference ground signal at the second terminal or based on a current flowing through the first terminal.

A system for an AC to DC PFC converter includes a first phase switch group connected to a first node to receive power from a first phase of a voltage source; a second phase switch group connected to a second node to receive power from a second phase of the voltage source; a third phase switch group connected to a third node to receive power from a third phase of the voltage source; a neutral phase switch group connected to a fourth node to be connected to a ground terminal of the voltage source; a first switch connected to the first node and the second node; and a second switch connected to the second node and the third node.