BATTERY CHARGER CONNECTED IN SERIES WITH AN ALTERNATING CURRENT LOAD CIRCUIT VIA A RECTIFIER

• US 3,697,850 A
• Filed: 12/31/1970
• Issued: 10/10/1972
• Est. Priority Date: 12/31/1970
• Status: Expired due to Term

• Current Assignee: David J Steele, Robert L. Martin, Theodore M. Heinrich
• Original Assignee: David J Steele, Robert L. Martin, Theodore M. Heinrich
• Inventors: Heinrich, Theodore M., Martin, Robert L., Steele, David J.
• Primary Examiner(s): Miller, J. D.
• Assistant Examiner(s): Hickey, Robert J.
• Application Number:
  US05/103,100
• Time in Patent Office: 649 Days
• Field of Search: 320/2,11,39,40,27,28,59-61,31,32 322/91,28 317/33SC
• US Class Current: 320/164
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• CPC Class Codes: H02J 7/02 for charging batteries from ac mains by converters

Abstract

A battery charger which receives energy for replenishing and maintaining a charge on a battery, from an alternating current source which may vary in voltage and frequency. The battery charger connects the battery in series with the alternating current source and its alternating current load via a rectifier, with the load current being shunted away from the battery when the charging current requirements of the battery are satisfied.

Claims

1. A battery charger comprising:

a source of alternating current which may vary in output voltage and frequency, rectifier means, said rectifier means having alternating current input terminals and unidirectional current output terminals, an alternating load circuit connected in series with said source of alternating current and said rectifier means, a battery, said battery being connected in series with said alternating current source and said alternating current load circuit through said rectifier means, with the load current provided by said alternating current source flowing through said battery, sensing means connected to be responsive to the terminal voltage of said battery, providing a signal when the terminal voltage of said battery reaches a predetermined magnitude, switching means shunting the load current provided by said alternating current source away from said battery, in response to the signal provided by said sensing means, and first protective means connected across the unidirectional output terminals of the rectifier means and to the switching means, said first protective means providing switching signals for the switching means when the voltage across the unidirectional output terminals exceeds a predetermined magnitude.

2. A battery charger comprising:

a source of alternating current which may vary in output voltage and frequency, rectifier means including input and output terminals, a battery, said battery being connected in series with said alternating current source through said rectifier means, with the load current provided by said alternating current source flowing through said battery, sensing means connected to be responsive to the terminal voltage of said battery, providing a signal when the terminal voltage of said battery reaches a predetermined magnitude, switching means including a plurality of solid state switching devices each having a control electrode connected to be responsive to the signal provided by the sensing means, said switching means shunting the load current provided by said alternating current source away from said battery, in response to the signal provided by said sensing means, and first protective means connected to the control electrodes of the solid state switching devices, and also to the output terminals of the rectifier means, said first protectiVe means providing signals for the control electrodes of the solid state switching devices at a predetermined voltage across the output terminals of the rectifier means, when the battery is disconnected from the rectifier means.

3. The battery charger of claim 2 wherein the protective means includes a voltage regulating diode.

4. A battery charger comprising:

a source of alternating current which may vary in output voltage and frequency, rectifier means, said rectifier means having alternating current input terminals and unidirectional current output terminals, an alternating load circuit connected in series with said source of alternating current and said rectifier means, a battery, said battery being connected in series with said alternating current source and said alternating current load circuit through said rectifier means, with the load current provided by said alternating current source flowing through said battery, sensing means connected to be responsive to the terminal voltage of said battery, providing a signal when the terminal voltage of said battery reaches a predetermined magnitude, switching means shunting the load current provided by said alternating current source away from said battery, in response to the signal provided by said sensing means, and first and second protective means, said first protective means being connected across the unidirectional output terminals of the rectifier means and to the switching means, providing switching signals for the switching means when the voltage across the unidirectional current output terminals exceeds a predetermined magnitude, said second protective means being connected to sense the magnitude of current flowing through the switching means, and to terminate the shunting of the load current through the switching means when the current reaches a predetermined magnitude.

5. A battery charger comprising:

an alternating current source which may vary in output voltage and frequency, an alternating current load circuit, a battery, a bridge rectifier having input terminals, first and second output terminals, diodes connected from the input terminals to the first output terminal, and diodes connected from the second output terminal to the input terminals, means serially connecting said alternating current source, said load circuit, and the input terminals of said bridge rectifier, means connecting said battery to the first and second output terminals of said bridge rectifier, sensing means connected to be responsive to the terminal voltage of said battery, providing signals when the battery voltage exceeds a predetermined magnitude, and a plurality of switching means, one of said switching means being connected from each input terminal of said bridge rectifier to its second output terminal, said switching means switching to their conductive states in response to signals from said sensing means, with the diodes connected to the second output terminal cooperating with the switching means connected to its associated input terminal when the switching means is conductive, to provide current paths in shunt with said battery, and with the diodes connected to the first output terminal being reverse biased by said battery to block current flow through said battery from said alternating current source, and first protective means connected across the first and second output terminals of the bridge rectifier and to the plurality of switching means, said first protective means providing switching signals for the plurality of switching means when the voltage across the first and second output terminals of the bridge rectifier exceeds a predetermined magnitude.

6. A battery charger comprising:

an alternating current source which may vary in output voltage and frequency, an alternating current load circuit, a battery, a bridge rectifier having input terminals, first and second output terminals, diodes connected from the iNput terminals to the first output terminal, and diodes connected from the second output terminal to the input terminals, means serially connecting said alternating current source, said load circuit, and the input terminals of said bridge rectifier, means connecting said battery to the first and second output terminals of said bridge rectifier, sensing means connected to be responsive to the terminal voltage of said battery, providing signals when the battery voltage exceeds a predetermined magnitude, a plurality of switching means, one of said switching means being connected from each input terminal of said bridge rectifier to its second output terminal, said switching means switching to their conductive states in response to signals from said sensing means, with the diodes connected to the second output terminal cooperating with the switching means connected to its a associated input terminal when the switching means is conductive, to provide current paths in shunt with said battery, and with the diodes connected to the first output terminal being reverse biased by said battery to block current flow through said battery from said alternating current source, and first and second protective means, said first protective means being connected across the first and second output terminals of the bridge rectifier and to the plurality of switching means, providing switching signals for the plurality of switching means when the voltage across the first and second output terminals of the bridge rectifier exceeds a predetermined magnitude, said second protective means being connected to sense the magnitude of current flowing through the plurality of switching means, and to terminate the shunting of current through the plurality of switching means when the current reaches a predetermined magnitude.