An AC-to-DC power converter configured to provide power factor correction and a single isolated low-voltage output. The power converter includes a single-stage resonant power converter including an isolation transformer, a resonant tank, a rectifier, and a bulk storage capacitor coupled to an output of the isolation transformer. In typical applications, at least one non-isolated power converter is coupled to the output of the single-stage isolated power factor correction converter.

Resonant power factor correction converter

A regulated power factor corrected power supply apparatus is provided. The apparatus includes an input rectifier circuit for receiving an input AC voltage and outputting a full-wave rectified DC voltage. A single-stage isolated buck-type converter is coupled with the input circuit. The converter circuit comprises an isolated buck-type converter circuit including an isolation transformer. An output rectifier and semiconductor tap switch are coupled to a secondary winding of the isolation transformer. The tap switch couples a larger portion of the secondary winding to an output bulk capacitor during the portions of the input sinewave half-cycle, which are low in amplitude. The tap switch enables the single-stage isolation buck-type converter to operate over a much larger portion of the input sinewave, but also allows the converter to operate at high-efficiency over the majority of the input sinewave.

High power factor isolated buck-type power factor correction converter

A power converter includes a transformer, a primary switch, an auxiliary switch, first and second resonance capacitors, and a secondary side rectification means. A switch mode power supply is formed to use reflected voltage and parasitic capacitance as an energy source for a transformer resonance. The auxiliary switch effectively exchanges energy between the primary inductance of the transformer and the first and second resonant capacitors. The auxiliary switch effectively switches the transformer resonance between two distinct frequencies. In one embodiment of the invention, the power converter can be, but is not limited to, a flyback converter and further includes a comparator and a driver. The comparator is for detecting the voltage across the second resonance capacitor and the driver is configured to drive the auxiliary switch based on the output state of the comparator. The resonant nature of the converter provides zero voltage (ZVS) for the primary switch as well as for the auxiliary switch.

Two terminals quasi resonant tank circuit

A power supply apparatus and method of regulating is provided. A clock generator circuit is configured for generating a clock signal at a predetermined frequency. An amplifier circuit is coupled with the clock generator circuit. The amplifier circuit includes a gain circuit coupled with the clock generator circuit. The amplifier circuit is configured to receive the clock signal at a switching element of the gain circuit. A controller circuit is configured for receiving a modulated error signal of the amplifier circuit and is configured for generating a pulse width modulated signal for controlling a duty cycle of the switching circuit. The switching circuit is configured for receiving the modulated error signal. The error signal is modulated using the clock signal to vary a gain value of the gain circuit according to the predetermined frequency. An output circuit is coupled with the switching circuit and is configured for generating a regulated voltage signal. The controller circuit uses the modulated error signal to substantially reduce harmonic distribution in a switching frequency of the switching circuit. Harmonic distribution in the switching circuit can be reduce by 10.0 db or greater.

Closed loop negative feedback system with low frequency modulated gain

Multiple power sources (314 and 354 of figure 3) for supplying power to a load. A triggering system to automatically and substantially cancel a ripple component of the input current drawn by the system. A master power source (314) and a slave power source (354) supply power to the load, ne triggering system results in the two power sources having switching aequencies that are substantially equal and switching cycles that are substantially 180* out of phase. Further, the method and the device contemplate the use of a local oscillator in the triggering system to ensure that the slave power source is triggered to the on position at a point in the switching cycle of the minster power source that is approximately 180- out of phase with a leading edge of the master switching drive siral. The system and method are advantageously used to provide a power factor correction aont-end for a switch-mode power supply. Power supplies with a diverse array of relationships between power supplied and switching gequency can be used.

Master slave critical conduction mode power converter

A system and a method may use variable-frequency power sources for supplying power to a load The system and method use phase detection in order to automatically and substantially equalize the currents supplied to a load by each of the variable-frequency power sources, and to cancel a ripple component of the input current drawn by the system First and second power sources supply power to the load The power sources have a similar relationship between their respective variable switching frequencies and the power that they supply to the load First and second switching frequencies of, respectively, the first and second power sources are locked to one another using phase detection to substantially equalize the power supplied to the load by each power source The system and method are advantageously utilized to provide a power factor correction front-end for a switch-mode power supply Power sources with non-linear and/or inverse relationships between power supplied and switching frequency can be used In alternate embodiments power from series power sources is equalized by equalizing voltages supplied by each power source to a load

System and method using phase detection to equalize power from multiple power sources

A system (30) and a method may use variable-frequency power sources for supplying power to a load (36). The system and method use phase detection in order to automatically and substantially equalize the currents supplied to a load by each of the variable-frequency power sources, and to cancel a ripple component of the input current drawn by the system. First and second power sources (31, 32) supply power to the load. The power sources have a similar relationship between their respective variable switching frequencies of, respectively, the first and second power sources are locked to one another using phase detection to substantially equalize the power supplied to the load by each power source. The system and method are advantageously utilized to provide a power factor correction front-end for a switch-mode power supply. Power sources with non-linear and/or inverse relationships between power supplied and switching frequency can be used. In alternate embodiments power from series power sources is equalized by equalizing voltages supplied by each power source to a load.

Arian M. Jansen

Papers

System and method using phase detection to equalize power from multiple power sources

System and method for equalizing power from two power sources