Abstract: A high voltage/ultrahigh voltage direct current transmission inverter side frequency control implementing method includes: transmitting a deviation between the inverter side power grid frequency and rated frequency to the inverter side frequency controller, wherein the frequency controller regulates and outputs a modulation quantity by adopting self-adaptive parameters according to different operation conditions; when the interstation communication is normal, the modulation quantity output of the inverter side frequency controller causes the rectifier side and the inverter side to form a new power/current order through the interstation communication; when the interstation communication is abnormal, converting the inverter side to current control from voltage control and converting the rectifier side to voltage control from current control; superposing the modulation quantity output of the inverter side frequency controller to the power/current order of the inverter side, changing the size of the transmission

Abstract: A neutral point clamped, multilevel level converter includes a DC voltage link; a first capacitor coupling one side of the DC link to a neutral point; a second capacitor coupling another side of the DC link to the neutral point; a plurality of phase legs, each phase leg including switches, each phase leg coupled to an AC node; a current sensor associated with each AC node; and a controller generating a PWM signal to control the switches, the controller generating a current zero sequence component in response to current sensed at each of the current sensors, the controller adjusting a modulation index signal in response to the current zero sequence component to produce the PWM signal.

Abstract: An electrical circuit for providing electrical power for use in powering electronic devices, such as monitors, televisions, white goods, data centers, and telecom circuit boards, is described herein. The electrical circuit includes an input terminal configured to receive an input power signal, an output terminal configured to provide an output power signal, and a plurality of voltage reduction circuit cells coupled between the input terminal and the output terminal. Each of the voltage reduction circuit cells includes a pair of flyback capacitors, a switching circuit, and a hold capacitor. The switching device is configured to operate the corresponding voltage reduction circuit cell at a charging phase and at a discharging phase. The plurality of voltage reduction circuit cells are configured to deliver the output power signal having a voltage level that is less than the voltage level of the input power signal.

Abstract: In one embodiment, a method of detecting a voltage can include: (i) generating a first current according to a first voltage and a converting resistor; (ii) charging a detection capacitor by the first current during a first time period of a switching cycle of a switching power supply; (iii) charging the detection capacitor by a second current during a second time period of the switching cycle; (iv) detecting a voltage across the detection capacitor to obtain a detection voltage at an end time of the second time period, where the first time period includes a rising portion of a current flowing through the inductor, and the second time period includes a decreasing portion of the inductor current; and (v) determining a state of a present output voltage of the switching power supply according to the detection voltage.

Abstract: An internal voltage generation circuit includes a first control signal generation unit suitable for generating a first control signal activated to a level of a second external voltage when a first external voltage is activated, a second control signal generation unit suitable for generating a second control signal that equals the higher of the second external voltage and an internal voltage, and a voltage generation unit suitable for generating the internal voltage by performing a charge pumping operation based on the second external voltage and an oscillation signal while blocking a current flowing through a generation node from which the internal voltage is generated, based on the first and second control signals.

Abstract: Power converter includes a switched power stage to generate an output voltage from an input voltage, and a controller to generate a pulse width modulation (PWM) signal for switching the switched power stage in dependence upon a voltage error signal. The voltage error signal is a difference between a reference voltage and the output voltage. The controller comprises a synchronizer to generate a first clock signal for clocking a low frequency domain of the controller, and a digital PWM controller clocked by the first clock signal and configured to determine an on-time information of the PWM signal and a PWM generator to generate the PWM signal based on the on-time information. The synchronizer is configured to synchronize a frequency of the PWM signal to a frequency imposed by the external reference signal by synchronizing a frequency of the first clock signal to the frequency imposed by the external reference signal.

Abstract: Systems and methods of increasing power converter efficiency are provided. A power converter includes a boost circuit configured to receive a DC input voltage ranging from a minimum input voltage value to a maximum voltage value, boost the DC input voltage to a predefined nominal voltage value when the DC input voltage has a value between the minimum input voltage value and the predefined nominal voltage value, and maintain the DC input voltage when the DC input voltage has a value that is greater than or equal to the predefined nominal voltage value and less than the maximum input voltage value. The unit also includes a DC-DC converter coupled to an output of the boost circuit, the DC-DC converter configured to convert the boosted DC voltage or the maintained DC voltage to a DC output voltage.

Abstract: Power converters that can allow for the transfer of DC power between a ground-referenced bus and a floating system are provided. In one embodiment, the power converter includes a ground-referenced DC bus associated with a DC voltage. The power converter further includes a first switching element, a second switching element, and a third switching element coupled in series between the ground-referenced DC bus and a ground reference. The power converter further includes a floating system associated with a floating DC voltage. The floating system can include a first terminal coupled to a first node between the first switching element and the second switching element. The floating system can further include a second terminal coupled to a second node between the second switching element and the third switching element.

Abstract: In one embodiment, a method of compensating for transmission voltage loss from a switching power supply, can include: (i) receiving a sampling signal that represents an output current of the switching power supply; (ii) delaying the sampling signal to generate a delayed sampling signal; (iii) converting the delayed sampling signal to generate a compensation signal; and (iv) regulating an output voltage of the switching power supply based on the compensation signal to compensate for the transmission voltage loss from the output voltage transmission to a load such that a voltage at the load is maintained as substantially consistent with an expected voltage at the load.

Abstract: A lamp oscillator which outputs a sawtooth wave signal to be compared with an error signal of an output voltage in order to generate a PWM signal. The oscillator includes a first charging current changing circuit, in which a current amplifier converts a differential voltage between the error signal and a reference voltage into a current and outputs the converted current. When the load of a switching power supply circuit is heavy, a capacitor is charged with a constant current and generates a sawtooth wave signal having a predetermined slope. During a light load, the first charging current changing circuit adds the current, which increases as the load becomes lighter, to the current to thereby make the slope of the sawtooth wave signal steeper.

Abstract: A transformer of distributed-constant type is provided between an AC power supply with a frequency f and a load with a resistance value R, and includes: a first converter connected to the AC power supply and having a length of ?/4; and a second converter provided between an end of the first converter and the load, and having a length of ?/4, where a wavelength at the frequency f is ?. Such a transformer has a small size and a light weight, and does not need a coil, an iron core, and the like as used in a conventional transformer.

Abstract: An apparatus includes a first auxiliary switch connected to a positive connection of a switching leg of a DC-to-DC converter. The switching leg includes a first main switch and a second main switch connected at a main switch midpoint. A second auxiliary switch is connected between a negative connection of the switching leg and the first auxiliary switch. A connection point between the first and second auxiliary switches is an auxiliary midpoint. An auxiliary inductor connects the auxiliary midpoint and the main switch midpoint. The main switch midpoint is also connected to other converter elements. The first and second main switches include a first capacitance a second capacitance. A switch regulation module regulates the first and second auxiliary switches to control current in the auxiliary inductor to provide or remove charge from the first and second capacitances to induce zero voltage switching for the first and second main switches.

Abstract: A power loss protection integrated circuit includes a current switch circuit (eFuse), a VIN terminal, a VOUT terminal, a buck/boost controller, and a storage capacitor terminal STR. The controller is adapted to work: 1) as a boost to take a low voltage from the VOUT terminal and to output a larger charging voltage onto the STR terminal, or 2) as a buck to take a higher voltage from the STR terminal and to buck it down to a lower voltage required on the VOUT terminal. The current switch circuit outputs a digital undervoltage signal (UV) and a digital high current signal (HC). These signals are communicated on-chip to the controller. Asserting UV causes the converter to begin operating in the buck mode. Asserting HC prevents the converter from operating in the boost mode.

Abstract: A power converter can be controlled to generate a target output power. The control process may include obtaining a target current reference for the power converter, sensing an output current of the power converter, and determining a difference between the target current reference and the sensed output current. The next switching duty cycle for the next switching period of the switching circuits in the power converter can be derived based on at least the present switching duty cycle of the present switching period, and the difference between the target current reference and the sensed output current. The switching circuits of the power converter can then be switched according to the derived next switching duty cycle in the next switching period.

Abstract: Single-input-multiple-output (SIMO) DC-DC converters and SIMO DC-DC converter control circuits are disclosed. An example DC-DC converter control circuit includes a switch controller to control respective switches of a SIMO DC-DC voltage converter that has multiple output circuits. The example control circuit also includes an arbitration circuit that determines a first one of the output circuits to have priority over other ones of the output circuits based on a priority signal, and selects a first output circuit to be charged during a first time slot based on the priority signal and based on first kick signals indicating that the at least two output circuits are to be charged. The control circuit also includes a next kick detector that determines a second one of the output circuits to be charged during a second time slot after the first time slot based on the priority.

Abstract: Various embodiments are described herein for methods and systems of regulating incoming voltage supplied from a utility power supply to a load. In one example embodiment, a voltage regulator adapted to be electrically interposed between the utility power supply and the load, each having at least one phase, is provided. The voltage regulator comprises an autotransformer having, for each phase, a series winding and a regulating winding, where the regulating winding has a plurality of taps and the series winding has a load side for connection to the load and a supply side for connection to the utility power supply.

Abstract: An electrical circuit for providing electrical power for use in powering electronic devices, such as monitors, televisions, white goods, data centers, and telecom circuit boards, is described herein. The electrical circuit includes an input terminal configured to receive an input power signal, an output terminal configured to provide an output power signal, and a plurality of voltage reduction circuit cells coupled between the input terminal and the output terminal. Each of the voltage reduction circuit cells includes a pair of flyback capacitors, a switching circuit, and a hold capacitor. The switching device is configured to operate the corresponding voltage reduction circuit cell at a charging phase and at a discharging phase. The plurality of voltage reduction circuit cells are configured to deliver the output power signal having a voltage level that is less than the voltage level of the input power signal.

Abstract: A switching power supply includes: a transformer having a primary coil and a secondary coil; a switching element that is connected in series to the primary coil of the transformer so as to turn a direct-current input voltage applied to the primary coil of the transformer ON and OFF; a rectifying and smoothing circuit that rectifies a voltage induced in the secondary coil of the transformer to generate a direct-current output voltage; and a control circuit that turns the switching element ON and OFF in accordance with the direct-current output voltage, wherein the control circuit includes an input correction circuit that detects a switching period of the switching element and limits a peak value of a current flowing through the switching element in accordance with the detected switching period.

Abstract: A switching power supply device includes a switching control circuit that generates a switching control signal such that a desired output voltage is generated from an input voltage, a drive circuit that turns on/off an output transistor in accordance with the switching control signal, and an on-pulse stop circuit that generates a pulse stop signal such that the number of ON pulses of the switching control signal is reduced in a state where a load is heavier than a first threshold but is lighter than a second threshold.

Abstract: A system and method for operating an inverter to maximize an overall efficiency of a power system is disclosed. A power system includes an inverter having an arrangement of switching devices that are selectively operable in On and Off states to invert a DC output to an AC output having controlled current and voltage. A controller selectively controls operation of the arrangement of switching devices via a discontinuous pulse width modulation (DPWM) scheme, so as to regulate an average voltage of the AC output. In controlling operation of the arrangement of switching devices via the DPWM scheme, the controller is programmed to generate a DPWM reference waveform having an initial phase angle, determine a system efficiency of the power system during operation, calculate an optimal phase angle for the DPWM reference waveform based on the determined system efficiency, and generate a DPWM reference waveform having the calculated optimal phase angle.