Power factor controller

• US 20030002303A1
• Filed: 03/15/2002
• Published: 01/02/2003
• Est. Priority Date: 10/01/1999
• Status: Active Grant

• Current Assignee: Flextronics Automotive USA Incorporated (Flex, Ltd.)
• Original Assignee: Christopher Allen Riggio, Garth Blair Woodland
• Inventors: Riggio, Christopher Allen, Woodland, Garth Blair
• Granted Patent: US 6,493,242 B1
• Time in Patent Office: Days
• US Class Current: 363/44
• CPC Class Codes: H01F 1/14791 Fe-Si-Al based alloys, e.g. Sendust
• CPC Class Codes: H01F 27/34 Special means for preventing or reducing unwanted electric or magnetic effects, e.g. no-load losses, reactive currents, harmonics, oscillations, leakage fields
• CPC Class Codes: H01F 3/10 Composite arrangements of magnetic circuits
• CPC Class Codes: H01F 3/14 Constrictions; Gaps, e.g. air-gaps in magnetic shunt paths H01F3/12
• CPC Class Codes: H02M 1/14 Arrangements for reducing ripples from dc input or output
• CPC Class Codes: H02M 1/32 Means for protecting converters other than automatic disconnection
• CPC Class Codes: H02M 1/4258 using a single converter stage both for correction of AC input power factor and generation of a regulated and galvanically isolated DC output voltage H02M1/4241 takes precedence
• CPC Class Codes: H02M 3/01 Resonant DC/DC converters
• CPC Class Codes: H02M 3/285 Single converters with a plurality of output stages connected in parallel parallel operation of a plurality of converters in dc distribution networks H02J1/10
• CPC Class Codes: H02M 3/33569 having several active switching elements H02M3/3353 takes precedence
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A drive with a high impedance input, low impedance output is created. When a switching or driving action requiring the sourcing and sinking of current from a common node in a wide frequency range is desired, the invention allows the creation of a simple, efficient, two switch drive system that functions across a wide range of conditions. The circuit uses a discrete N-Channel FET paired with discrete PNP transistors. A high impedance input node is formed by connecting the FET gate to the transistor base. The differential threshold voltage that exists between the FET gate and the transistor base prevents the two devices from generating conflicting currents at the output node formed by the common source emitter. The circuit further lends itself to output waveform variations as may be required for various drive strategies by manipulating the input signal processing to custom modify the resulting output voltage and current.

Claims

1. (FIG. 4) An AC to DC converter comprising:

a first and second AC input line;

an electromagnetic interference (EMI) filter circuit;

an AC to DC rectifier circuit connected to the EMI filter circuit;

a positive output terminal of the AC to DC rectifier circuit is connected to a first node of a primary winding of an inductor which has a magnetic element operating in a non-saturated region (NSME);

a second node of the primary winding of the inductor is connected to an anode of a second rectifier and is connected to a drain of a N-Channel field effect transistor (FET);

a source of the FET is connected to a negative node of the AC to DC rectifier circuit; and

a controller circuit that modulates a FET conduction period to maintain a constant output voltage receives feedback from an output voltage of the converter.

2. The converter of claim 1 further comprising a bypass diode to conduct input transients around the converter to an output capacitor.

3. (FIG. 4) An AC to DC converter comprising:

an AC input power connection;

an EMI filter circuit connected to the AC power connection;

a feedback circuit;

a controller circuit;

an inductor having a magnetic element operating in a non-saturated region (NSME);

a line rectifier circuit;

an output rectifier circuit;

a switching circuit;

said line rectifier circuit connected to an output of the EMI filter circuit;

a positive output node of the line rectifier circuit connected to a first node of a primary winding of the inductor;

a second node of the primary winding of the inductor is connected to an anode of the output rectifier circuit and to a drain of the switching circuit;

a cathode of the output rectifier circuit is connected to a positive node of an output capacitor;

a source of the FET is connected to a negative node of the line rectifier circuit; and

the feedback circuit has a connection between a converter output and the controller, thereby providing a regulated DC output.

4. The converter of claim 3 further comprising a bypass diode to conduct input transients around the converter to an output capacitor.

5. (FIG. 4) An AC to DC power factor correcting boost converter, said boost converter comprising:

an AC input power connection;

an electromagnetic interference (EMI) filter circuit means functioning to block conducted EMI from the AC input power connection;

an AC to DC rectifier circuit means functioning to convert an AC input voltage to a DC voltage output;

said AC to DC rectifier circuit means connected between the EMI filter circuit means and a first node of a primary winding of a boost inductor means;

said boost inductor means functioning to provide a boost voltage added to the DC voltage output using its magnetic element operating in a non-saturated region (NSME);

a second node of the primary winding of the boost inductor means is connected to an anode of a second rectifier and to an input node of an N-Channel switch means;

said N-Channel switch means functioning to excite the primary winding of the boost inductor;

an output node of the N-Channel switch means is connected to a negative node of the AC to DC rectifier circuit means;

a controller circuit means functioning to modulate a trigger node of the N-Channel switch means; and

a feedback circuit means connected between an output of the boost converter and the controller circuit means functioning to maintain a constant voltage output, thereby providing an EMI filtered, regulated, power factor corrected, non-isolated, DC line output.

6. The apparatus of claim 5 further comprising a bypass means functioning to conduct input transients directly around the boost converter to an output storage device means functioning to create an output from a transient through the storage drive means which is common to the boost converter output, thereby minimizing voltage drops while protecting the boost converter and its load.