A power controller for use in a PFC power converter is capable being immune from audible noise during the test of load transient response. A transconductor with a transconductance compares an output voltage of the PFC power converter with a target voltage to provide a compensation current, which builds up a compensation voltage. An ON-time controller is configured to end an ON time of a power switch in response to the compensation voltage. An OFF-time controller is configured to end an OFF time of the power switch. A compensation-voltage designator presets the compensation voltage. A status detector controls the transconductor, the ON-time controller, the OFF-time controller, and the compensation-voltage designator, in response to the output voltage, a top-boundary voltage and a bottom-boundary voltage.

The control apparatus is used with the electrical power converter working to an inputted one of ac voltage and a terminal-to-terminal voltage at a capacitor into the other. The control apparatus calculates a sine-wave command value for a reactor current based on the ac voltage and an amplitude command value indicating an amplitude of the reactor current. The control apparatus also operates switches SW in peak-current mode control to bring the reactor current into agreement with a command value for the reactor current to which a current correction value is added. The control apparatus sets the current correction value to include a component of fluctuation in the terminal-to-terminal voltage at the capacitor based on the ac voltage Vac.

A bidirectional power factor correction (PFC) module is coupled to an AC power source, an energy storage unit, and a DC bus. The bidirectional PFC module includes a bridge arm assembly and a control unit. The bridge arm assembly includes a first bridge arm, a first inductor, a second inductor, and a second bridge arm. The control unit provides a plurality of control signals to control the first bridge arm and the second bridge arm to make the bidirectional PFC module operate in an AC power supply mode, a DC power supply mode, or a power feed mode.

A power control circuit includes an alternating current (AC) power source, a rectifier and a valley-fill circuit. The AC power source is configured to receive an AC voltage. The rectifier is configured to convert the AC voltage into a rectified voltage. The valley-fill circuit includes: an inductor, having a first terminal coupled to the rectifier, and a second terminal; a first resistor, having a first terminal coupled to the second terminal of the inductor, and a second terminal; a diode, having a cathode coupled to the second terminal of the inductor, and an anode; and a first capacitor, having a first terminal coupled to the second terminal of the first resistor and the anode of the diode, and a second terminal coupled to ground.

A power control circuit includes an alternating current (AC) power source, a rectifier and a valley-fill circuit. The AC power source is configured to receive an AC voltage. The rectifier is configured to convert the AC voltage into a rectified voltage. The valley-fill circuit includes: an inductor, having a first terminal coupled to the rectifier, and a second terminal; a first resistor, having a first terminal coupled to the second terminal of the inductor, and a second terminal; a diode, having a cathode coupled to the second terminal of the inductor, and an anode; and a first capacitor, having a first terminal coupled to the second terminal of the first resistor and the anode of the diode, and a second terminal coupled to ground.

A method and apparatus for detection of a failure of a rectifier connected to a passive harmonic filter with a tuned circuit reactor, or of the filter itself, using low cost voltage sensing, modeling of reactor resistance and saturable inductance, and a mathematical integration. The harmonic spectrum of the rectifier current is used to determine an estimate of the rectifier impedance. A template of expected rectifier current is calculated, and compared against a rectifier current calculated on the basis of sensed voltages, to generate a difference signal. The difference signal is compared against a predetermined fault threshold to determine if an error has occurred. The apparatus includes a DSP obtaining the voltages of the source and load, and the tuned circuit reactor voltage, and configured to compare the currents calculated from the actual voltages with the currents in the template, and to thereby determine whether to annunciate a fault.

A control method of a PFC (Power Factor Correction) circuit having at least one power switch, the control method having: producing an effective value of an input voltage; generating a compensation signal based on an output voltage and an output voltage reference signal; generating an on time signal based on the compensation signal, the effective value of the input voltage, a first on time period value and a second on time period value; generating an on time delay signal based on the input voltage, the output voltage, the first on time period value, the effective value of the input voltage and the compensation signal; and generating a current valley signal based on the input voltage, the effective value of the input voltage, the compensation signal, the second on time period value, and an inductance value of the inductor adopted by the PFC circuit.

A power factor correction circuit configured to increase the amount of useful power in an AC electrical system. The power factor correction circuit optionally includes one or more capacitors and one or more resistors configured to realign a phase angle between a voltage and current of an AC power source. Examples are offered illustrating the disclosed circuit in use with a single phase or multi-phase AC power source ranging in voltage from 100 volts or less to 500 volts or more.

In this work, it is shown for the first time that the power and the impedance in a transformer circuit depend on the phase of the flux, hence the phase of the current. There is a phase change when the flux travels the magnetic core, and formulas for the effect of the phase change in the power and the impedance are derived. Therefore, the power factor can be adjusted so that the power is delivered more at the load than that, at the primary supplied by the source.

A dual voltage power system for selectively providing direct current (DC) at two different voltages. The system includes a plurality of universal rectifiers each of which may be configured to operate under a plurality of operating modes using a plurality of switches which may be controlled by a power shelf controller.