A direct-current voltage conversion circuit having on/off control with a dead-time period performed alternately on a first switch and a second switch included in a direct-current voltage conversion circuit. When alternating current flows in a series circuit part including two transformers magnetically independent, current flows in an output circuit including a secondary side of one transformer, and energy is accumulated in the other transformer. The permeabilities of the magnetic cores in the first and second transformers is between 15 and 120.

Controllers for power converters, power converters and corresponding methods are provided.

A controller of a power converter including a first power stage and a second power stage receives an indication of an output voltage of the power converter, where the indication is measured at the primary side of the power converter. Based on the indication, a control related to an intermediate voltage of the power converter is performed.

A circuit with a metal-oxide semiconductor field-effect transistor and a diode module is applied to a power factor correction circuit, which can effectively reduce the heat generated by the whole system under heavy load, The circuit includes a metal-oxide semiconductor field-effect transistor and a diode module and a load determination unit. The diode module includes a plurality of diodes with a switch. The load determination unit can control the connection/disconnection of each diode in the diode module based on the magnitude of the load current. It can effectively reduce the current generated by each diode due to the load, thereby reducing the heat generation of the overall system. Moreover, due to the contact capacitance effect after the diodes are connected in parallel, the electromagnetic interference (EMI) characteristics of the power factor correction circuit of the system can be further optimized.

A metal-oxide semiconductor field-effect transistor with asymmetric parallel die and an implementation method thereof, comprising an inductor, a load recognition control unit and a metal-oxide semiconductor field-effect transistor having a first die, a second die, and a switch. The first die is larger in size than the second die. The inductor can produce a voltage signal when the load changes. The switch is controlled by the load recognition control unit such that different dies are switched on under different load conditions, thereby improving efficiency under light load condition in addition to reducing volume and cost.

An apparatus includes a controller. The controller monitors a magnitude of first current supplied by an output voltage of a first power converter to power a dynamic load. The controller controls a second power converter to supply second current through the dynamic load based on the monitored magnitude of first current.

Power conversion device for supplying a load with a PWM signal, comprising an inductive filter having at least an output configured to be connected to the load, the device comprising: a power conversion module supplied by an input voltage and configured for providing a plurality of output signals wherein one of the plurality of output signals is supplied to the filter; a conversion ratio control stage coupled to the power conversion module; and a controller configured to: determine a requested conversion ratio based on the input voltage and a target reference voltage; and based on the requested conversion ratio, control the conversion ratio control stage to operate in either a first operating mode, whereby the power conversion module provides the output signals in accordance with a first conversion ratio, or a second operating mode, whereby the power conversion module provides the output signals in accordance with a second conversion ratio.

Disclosed herein is a power control apparatus for sub-modules in an MMC, which controls stable supply of power to sub-modules in MMC connected to an HVDC system and a STATCOM. The power control apparatus includes at least one first resistor connected between P and N buses of MMC; a second resistor connected in series with the first resistor; a switch connected in series with the second resistor; a third resistor connected in parallel with the second resistor and the switch which are connected in series; a Zener diode connected in parallel with the third resistor; and a DC/DC converter connected between both ends of the Zener diode and configured to convert voltage across both ends of the Zener diode into low voltage, and supply the low voltage to the sub-modules, wherein a magnitude of current flowing through the Zener diode is controlled depending on ON/OFF switching of the switch.

Methods and apparatus for a body diode conduction sensor configured for coupling to a switching element. In embodiments, the sensor comprises first and second voltage divider networks coupled to a voltage source and a diode coupled to the switching element and to the first voltage divider network, wherein the diode is conductive at times corresponding to body diode conduction of the switching element decreasing the DC average voltage at the output node of the first voltage divider network. A differential output voltage can be coupled to the first and second voltage divider networks with an output signal corresponding to a time of the body diode conduction of the switching element.

System controller and method for regulating a power converter. For example, the system controller includes a first controller terminal and a second controller terminal. The system controller is configured to receive an input signal at the first controller terminal and generate a drive signal at the second controller terminal based at least in part on the input signal to turn on or off a transistor in order to affect a current associated with a secondary winding of the power converter. Additionally, the system controller is further configured to determine whether the input signal remains larger than a first threshold for a first time period that is equal to or longer than a first predetermined duration.

This application provides example circuit modules and example electronic devices comprising the circuit module. One example circuit module includes a power input terminal, a power output terminal, a first switching transistor, a second switching transistor, a comparison unit, a boost unit, an energy storage unit, and a direct current conversion unit, where the first switching transistor is turned on and the second switching transistor is cut off when a source voltage input by the power input terminal to the comparison unit is greater than the preset threshold, or the first switching transistor is cut off and the second switching transistor is turned on when a source voltage input by the power input terminal to the comparison unit is less than or equal to the preset threshold.