WIDE BAND BOOST REGULATOR POWER SUPPLY

• US 3,641,422 A
• Filed: 10/01/1970
• Issued: 02/08/1972
• Est. Priority Date: 10/01/1970
• Status: Expired due to Term

• Current Assignee: Dennis G. Mccaughey, Robert P. Farnsworth
• Original Assignee: Dennis G. Mccaughey, Robert P. Farnsworth
• Inventors: Farnsworth, Robert P., McCaughey, Dennis G.
• Primary Examiner(s): Pellinen, A. D.
• Application Number:
  US05/077,168
• Time in Patent Office: 495 Days
• Field of Search: 321/2 323/4,8,17,20,22T,22SC,38,94H,DIG.1
• US Class Current: 323/224
• CPC Class Codes: H02M 3/158 including plural semiconductor devices as final control devices for a single load
• 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 power supply which, in one embodiment, provides to a load a relatively constant DC (direct current) output voltage at a voltage level equal to or greater than that being supplied from a variable DC voltage source. The power supply includes a first switching circuit controlled by a voltage sensing circuit to allow energy to be transferred from a current storage device to a voltage storage device to maintain the amplitude of the output voltage within predetermined levels, and also includes a second switching circuit controlled by a current sensing circuit to allow the amplitude of circuit to be maintained within predetermined limits.

Claims

1. A power supply for supplying regulated power to a load comprising:

current generator means, coupled to the load and adapted to receive an input unregulated voltage, for supplying a current at least equal in amplitude to the maximum current required by the load;

input means coupled to said current generator means for sensing the current through said current generator means, said input means being responsive to current at a lower current level through said current generator means for providing a path for the current through said current generator means to increase to an upper current level, said input means being responsive to current at the upper current level through said current generator means for coupling said current generator means to the load to allow said current generator means to increase the output voltage as needed;

output means, coupled to said current generator means and to the load, for sensing the amplitude of the output voltage across the load, said output means being responsive to the upper voltage level of the sensed output voltage for preventing said current generator means from supplying current to the load, said output means being responsive to the lower voltage level of the sensed output voltage for allowing said current generator means to supply a current to the load, said output means including;

a capacitor coupled across the load and being responsive to the current supplied by said current generator means for developing the output voltage for the load;

a voltage sensing circuit coupled to the load for sensing the amplitude of the output voltage developed across said capacitor; and

a first switching circuit coupled to said current generator means and being controlled by said voltage sensing circuit to close when the output voltage has increased to at least the upper voltage level and to open when the output voltage has decreased to at least the lower voltage level, said current generator means being bypassed back to itself through the closure of said first switching circuit by said voltage sensing circuit when the output voltage has increased to at least the upper voltage level in order to prevent said capacitor from charging to a higher output voltage.

2. The power supply of claim 1 wherein said input means includes:

a current sensing circuit coupled to said current generator means for sensing the amplitude of the current through said current generator means;

a second switching circuit coupled to said current generator means and said voltage sensing circuit and being controlled by said current sensing circuit to close and provide a path for increasing the current through said current generator means when the current through said current generator means has decreased to at least the lower current level and to open when the current through said current generator means has increased to at least the upper current level; and

diode means coupled between said second switching circuit and the load and having conductive and nonconductive states, said diode means being in the conductive state to allow current from said current generator means to pass therethrough to charge said capacitor to a higher output voltaGe when said second switching circuit is open, said diode means being in a nonconductive state to prevent said capacitor from discharging through said second switching circuit when said second switching circuit is closed.

3. The power supply of claim 2 wherein the current flowing through said current generator means produces a magnetic field having a strength proportional to the amplitude of the current therethrough and said current sensing circuit includes:

a device placed in the magnetic field of said current generator means to sense the strength of the magnetic field in order to develop a first voltage having an amplitude proportional to the amplitude of the current flowing through said current generator means; and

amplifier means coupled between said device and said second switching circuit and being responsive to the first voltage of said device for developing a signal to close said second switching circuit when the current through said current generator means has decreased to at least the lower current level and to open said second switching circuit when the current through said current generator means has increased to at least the upper current level.

4. The power supply of claim 3 wherein said current generator means is an inductor.

5. The power supply of claim 3 wherein said current generator means is a transformer having a primary winding and a secondary winding, said primary winding coupled to said second switching circuit and said secondary winding coupled to said first switching circuit, said device being inserted in the magnetic field produced by current flowing through said primary and secondary windings of said transformer in order to sense the total strength of said magnetic field and control said second switching circuit as a function of the total magnetic field being sensed.

6. The power supply of claim 2 wherein said current generator means is an inductor and said current sensing circuit includes:

a sensing resistor coupled in series with said inductor;

a differential amplifier coupled across said sensing resistor for developing an output voltage proportional to the amplitude of current flowing through said inductor; and

amplifier means coupled between the output of said differential amplifier and said second switching circuit and being responsive to the output of said differential amplifier for developing a signal to close said second switching circuit when the current through said inductor has decreased to at least the lower current level and to open said second switching circuit when the current through said inductor has increased to at least the upper current level.

7. The power supply of claim 2 wherein:

said current generator means includes a transformer having a primary winding and a secondary winding, said primary winding coupled to said second switching circuit and said secondary winding coupled to said first switching circuit; and

said current sensing circuit includes first and second sensing resistors serially coupled to said primary and secondary windings respectively for respectively developing voltages indicative of the amplitudes of currents flowing through said primary and secondary windings, first and second differential amplifier circuits each having input and output circuits, said input circuit of said first differential amplifier circuit being coupled across said first sensing resistor to develop a first voltage related to the amplitude of the current flowing through said primary winding, first means coupled to the output of said first differential amplifier and to said second sensing resistor for developing a second voltage related to the amplitude of the total current flowing through said primary and secondary windings, said input circuit of said second differential amplifier being adapted to receive a reference voltage and the second voltage in order to develop a third voltage for controlling the operation of said second switching circuit.

8. A regulated power supply comprising:

first storage means for storing voltage;

second storage means for storing current;

first circuit means coupled to said first storage means for sensing the amplitude of voltage stored by said first storage means;

first switching circuit means coupled to said second storage means and controlled by said first circuit means to allow the stored current to be used to increase the amplitude of the stored voltage when the stored voltage has decreased to at least a lower voltage level and to prevent the stored current from being used to further increase the amplitude of the stored voltage when the stored voltage has increased to at least an upper voltage level;

second circuit means coupled to said second storage means for sensing the amplitude of the current stored by said second storage means; and

second switching circuit means coupled to said second storage means and controlled by said second circuit means for selectively allowing the amplitude of the current in said second storage means to be maintained within first and second predetermined current limits.

9. A power supply for supplying regulated power to a load comprising:

current generator means, coupled to the load and adapted to receive an input unregulated voltage, for supplying a current at least equal in amplitude to the maximum current required by the load;

a capacitor coupled to said current generator means and across the load and being responsive to the current supplied by said current generator means for developing the output voltage for the load;

a voltage sensing circuit coupled to the load for sensing the amplitude of the output voltage developed across said capacitor;

a first switching circuit coupled to said current generator means and being controlled by said voltage sensing circuit to close when the output voltage has increased to at least the upper voltage level and to open when the output voltage has decreased to at least the lower voltage level, said current generator means being bypassed back to itself through the closure of said first switching circuit by said voltage sensing circuit when the output voltage has increased to at least the upper voltage level in order to prevent said capacitor from charging to a higher output voltage;

a current sensing circuit coupled to said current generator means for sensing the amplitude of the current through said current generator means;

a second switching circuit coupled to said current generator means, said second switching circuit being controlled by said current sensing circuit to close and provide a path to increase the amplitude of current through said current generator means when the current through said current generator means has decreased to at least the lower current level and to open when the current through said current generator means has increased to at least the upper current level; and

diode means coupled between said current generator means and the load for allowing current from said current generator means to charge said capacitor to a higher output voltage when said first and second switching circuits are open.

10. The power supply of claim 9 wherein:

said current generator means includes a transformer having a primary winding and a secondary winding, said primary winding coupled to said second switching circuit and said secondary winding coupled to said first switching circuit; and

said current sensing circuit includes first and second sensing resistors serially coupled to said primary and secondary windings respectively for respectively developing voltages indicative of the amplitudes of currents flowing through said primary and secondary windings, first and second differential amplifier circuits each having input and output circuits, said input circuit of said first differential amplifier circuit being coupled across said first sensing resistor to develop a first voltage related to the amplitude of the current flowing through said primary winding, first meAns coupled to the output of said first differential amplifier and to said second sensing resistor for developing a second voltage related to the amplitude of the total current flowing through said primary and secondary windings, said input circuit of said second differential amplifier being adapted to receive a reference voltage and the second voltage in order to develop a third voltage for controlling the operation of said second switching circuit.

11. The power supply of claim 9 wherein the currents flowing through said current generator means produces a magnetic field having a strength proportional to the amplitudes of the currents therethrough and said current sensing circuit includes:

a device placed in the magnetic field of said current generator means to sense the strength of the magnetic field in order to develop a first voltage having an amplitude proportional to the amplitudes of the currents flowing through said current generator means; and

amplifier means coupled between said device and said second switching circuit and being responsive to the first voltage of said device for developing a signal to close said second switching circuit when the currents through said current generator means has decreased to at least the lower current level and to open said second switching circuit when the currents through said current generator means has increased to at least the upper current level.

12. The power supply of claim 11 wherein said current generator means is a transformer having a primary winding and secondary winding means for receiving energy from said primary winding, said primary winding coupled to said second switching circuit and said secondary winding means coupled to said first switching circuit, said device being inserted in the magnetic field produced by current flowing through said primary winding and said secondary winding means of said transformer in order to sense the total strength of said magnetic field and control said second switching circuit as a function of the total magnetic field being sensed.