Polyphase alternator and dual voltage battery charging system for multiple voltage loads

• US 4,816,736 A
• Filed: 03/12/1987
• Issued: 03/28/1989
• Est. Priority Date: 03/12/1987
• Status: Expired due to Term

• Current Assignee: Johnson Controls Technology Company (Johnson Controls International plc)
• Original Assignee: Globe-Union Inc.
• Inventors: Dougherty, Thomas J., Johnson, Richard T.
• Primary Examiner(s): HICKEY, ROBERT
• Application Number:
  US07/025,217
• Time in Patent Office: 747 Days
• Field of Search: 320/15, 320/17, 320/6, 322/90, 322/94
• US Class Current: 320/116
• CPC Class Codes: H02J 7/1423 with multiple batteries

Abstract

A 24/12 volt battery power supply for a vehicle includes two 12 volt batteries connected in series, and having first and second 24 volt terminals to the opposite ends of the batteries and a 12 volt terminal to the center common connection of the batteries. The 12 volt loads are divided into equal right and left side vehicle loads and the right side is connected across one battery and the left side is connected across the second battery. A three phase wye-connected alternator has the winding connected to a full wave three phase rectifier, the D.C. output of which is connected to the 24 volt terminals. The center common connection of the winding is connected directly to the 12 volt terminal. The system operates with balanced currents and charges on the two 12 volt batteries so long as the 12 volt loads remain balanced. Control loads are selectively connected to the right and left side loads if a 12 volt load is lost, disconnected or otherwise changes to maintain the balanced system but only if the imbalance due to lost loads is large. In another embodiment, the full wave rectifiers are connected to conduct the opposite half cycles of the alternator output. The controlled rectifiers for each half cycle have the gates connected to a common gate source, and a logic circuit monitors the voltage of each battery and actuates one or the other of the rectifier groups to prevent one battery segment from significantly varying in voltage with respect to the other.

Claims

1. A dual voltage battery power supply system for vehicular devices having multiple load means of different voltages, comprising

a battery means having first and second voltage terminal means defining a high voltage supply and having an intermediate terminal means defining first and second low voltage supplies with respect to said first and second voltage terminal means,

a polyphase alternator having a polyphase winding including a plurality of phase windings connected to polyphase output terminal means for supplying a polyphase output voltage and having a center terminal means connected to each of said phase windings to divide the voltage of each phase winding,

a single full wave rectifying circuit connecting said battery means to said polyphase output terminal means and to said first and second voltage terminal means to supply full wave rectified power to said first and second voltage terminal means and to said battery means,

and means connecting said intermediate terminal means of said battery means to said center terminal means of said polyphase winding for connecting the battery means to the opposite sides of said intermediate terminal means into separate charging circuits with the polyphase winding and said full wave rectifying circuit whereby the voltage of each phase winding is divided and connected in circuit through said rectifying circuit.

2. The power supply system of claim 1 includes first and second load units of the same voltage rating, said first and second load units having essentially equal load levels, said first load unit connected between said intermediate terminal means of said battery means and said first voltage terminal means, and second load unit connected between said intermediate terminal means of said battery means and said second voltage terminal means.

3. The power supply system of claim 2 including an auxiliary load means, switch means connecting said auxiliary load means in circuit with said first and second load units, and control means to monitor the voltage level of said first and second low voltage supplies and operable to actuate said switch means to connect said auxiliary load means in circuit with one of said first and second load units in response to a selected voltage difference for re-establishing equal voltages in said first and second low voltage supplies.

4. The power supply system of claim 3 wherein said auxiliary load means includes a resistor means connected to said intermediate terminal means, and said switch means connects the resistor means to said first or second voltage terminal means.

5. The power supply system of claim 3 wherein said auxiliary load means includes separate first and second loads, each auxiliary load includes a resistor means, said switch means including a first solid state switch unit connecting said first load in parallel with said first low voltage supply, and said switch means including a second solid state switch unit connecting said second load in parallel with said second low voltage supply.

8. The battery power supply system of claim 1 wherein said battery means has a low antimony-lead or non-antimony lead battery grid means and has a rapid change in voltage with change in current.

6. A dual voltage battery power supply system for vehicular devices having multiple load means of different voltages, comprising

a battery means having first and second voltage terminal means defining a high voltage supply and having an intermediate terminal means defining first and second low voltage supplies with respect to said first and second voltage terminal means,

a polyphase alternator having a polyphase winding including a plurality of phase windings connected to polyphase output terminal means for supplying a polyphase output voltage, said polyphase winding wound as a wye-connected winding having a common center connection connected to said intermediate terminal means,

a single full wave rectifying circuit connecting said battery means to said polyphase output terminal means and to said first and second voltage terminal means to supply full wave rectified power to said first and second voltage terminal means and to said battery,

and means connecting said intermediate terminal means of said battery to said center connection of said polyphase winding for connecting the battery means to the opposite sides of said intermediate terminal means into separate charging circuits with said polyphase winding and said full wave rectifying circuit whereby the voltage of each phase winding is divided and connected in circuit through said rectifying circuit.

7. The power supply system of claim 6 wherein one of said first and second voltage terminal means connected as a common ground whereby said first low voltage supply is floating voltage and second low voltage supply is a grounded voltage.

9. The battery power supply system of claim 6 wherein said full wave rectifying circuit includes solid state gated unidirectional conductors, and means to monitor the voltage of said first and second low voltage supplies and connected to said gated unidirectional conductors to establish said separate charging circuits for maintaining a minimum charge on each of said first and second low voltage supplies.

10. A battery power supply system for a mobile vehicle for supplying a first load at a selected voltage and a second load at one half said selected voltage, comprising

a battery means having a series of cells connected to each other between first and second voltage terminal means to establish said selected voltage and having a central connection between two cells of said series of cells, a center terminal means connected to the central connection of said series of cells to define said half voltage at said center terminal means,

a polyphase alternator having a polyphase winding including a plurality of phase winding connected as a wye-connected winding to polyphase output terminal means for supplying a polyphase output voltage and having center terminal means connected to said wye-connected phase winding to divide the voltage of each phase winding and having the wye-connected phase winding connected to establish individual battery charging circuits across said first and second voltage terminal means and across each of the center terminal means and the first and second voltage terminal means,

a single full wave rectifying circuit connecting said battery means to said polyphase output terminal means and to said first and second voltage terminal means to supply full wave rectified power to said first and second voltage terminal means and to said battery means,

and means connecting said intermediate terminal means of said battery to said center terminal means of said polyphase winding for connecting the battery means to the opposite sides of said intermediate terminal means onto separate charging circuits with said polyphase winding and said full wave rectifying circuit whereby the voltage of each phase winding is divided and connected in circuit through said rectifying circuit,

said second load being formed into first and second load units of similar load resistance, said first load unit connected between the center terminal means and the first voltage terminal means, said second load unit connected between the center terminal means and said second voltage terminal means, and

third load means, connecting means connecting said third load means to said first and second load units to balance the first and second load units.

11. The battery power supply system of claim 10 wherein said battery means has a rapid change in voltage with current

12. The battery power supply system of claim 10 wherein one of said first and second voltage terminal means is connected as a system ground.

13. A multiple direct current supply system for a vehicle having first direct current loads requiring a first direct current voltage and second direct current loads requiring a second direct current voltage and third direct current loads requiring a third direct current voltage, comprising

a three phase alternator having a three phase winding connected in a wye-connection winding with a common center connection means and three phase winding terminations,

a battery unit having first and second voltage terminal means having an output voltage equal to said first direct current voltage and having a third terminal means defining said second direct current voltage with said first terminal means and third direct current voltage with said second terminal means,

a single rectifying circuit having first and second output terminal means and connected to the phase winding terminations of said three phase winding for establishing a direct current voltage on the order of said first direct current voltage at said first and second output terminal means, and

circuit means connecting said first and second output terminal means to said first and second voltage terminal means and connecting said common connection means to said third terminal means.

14. The direct current supply system of claim 13 including load control means connected between said third terminal means and said first and second output terminal means to control total loads coupled to said second and third terminal means.

15. A direct current power supply for vehicle having a plurality of 12 volt load units and at least one 24 volt load unit, comprising

a three phase alternator having a field winding and a wye-connected three phase winding with a common connection and three phase winding terminations, said alternator having means to limit the current output with speed above a selected level and having an output voltage controlled by said field winding and the speed of the alternator, said three phase winding wound to minimize the voltage generated at said common connection,

a full wave diode rectifier unit having three parallel rectifying branches connected in parallel between a positive output lead and a negative output lead, each of said branches having at least two series connected diodes and having a branch center tap connected to one of said phase winding terminations,

a first 12 volt battery meads,

a second 12 volt battery means connected in series with said first 12 volt battery means and having first and second 24 volt output terminals at t he opposite ends to define a 24 volt battery means, a central common connection between said first and second 12 volt battery means,

first and second 24 volt terminal means connected to said output terminals of the series connected first and second 12 volt battery means and adapted to supply power to a 24 volt load,

volt terminal means connected to the common connection of said first and second 12 volt battery means,

a first 12 volt load means, first control means connecting said first load means between said first 24 volt terminal means and said 12 volt terminal means,

a second 12 volt load means, second control means connecting said second load means between said 12 volt terminal means and said second 24 volt terminal means,

each of said control means including a control input means for controlling the level of the said corresponding first and second load means,

a voltage comparator means connected to said first and second 24 volt terminal means and said 12 volt terminal means to compare the voltage appearing across said first and second load means and operable to vary the level of said load means to establish and maintain essentially equal voltage between said third 12 volt terminal means and each of said first and second 24 volt terminal means and thereby across said first and second loads means.

16. The direct current power supply of claim 15 wherein each of said load means includes a resistive load and said control means includes a variable conductive means having a control input means connected to said comparator means to vary the conductive of said conductive

17. The power supply of claim 16 wherein one of said first and second 24 volt output terminal means is connected to a common ground for said electrical system.

18. A battery power supply system for a vehicle for supplying first load means at a selected voltage and second load means at one half said selected voltage, comprising

a battery means having a series of cells connected between first and second voltage terminal means to establish said selected voltage and having a central connection between two cells of said series of cells, a center terminal means connected to said central connection in said series of cells to define two battery supplies having said half voltage between said center terminal means and each of said first and second voltage terminal means,

an alternator having a polyphase winding including a plurality of phase windings connected as a wye-connected winding to polyphase output terminal means for supplying a polyphase output voltage and having center terminal means connected to said wye-connected phase winding to divide the voltage of each phase winding and having the wye-connected winding connected to establish individual battery charging circuits across said first and second voltage terminal means and across each of the center terminal means and the first and second voltage terminal means,

a single full wave rectifying circuit connecting said battery means to said polyphase output terminal means and to said first and second voltage terminal means to supply full wave rectified power to said first and second voltage terminal means and to said battery means,

and means connecting said intermediate terminal means of said battery means to said center terminal means of said polyphase winding for connecting the battery means to the opposite sides of said intermediate terminal means into separate charging circuits with said polyphase winding and said full wave rectifying circuit whereby the voltage of each phase winding is divided and connected in circuit through said rectifying circuit,

said second load means being formed into first and second load units of similar load resistance, said first load unit connected between the center terminal means and said first full voltage terminal means, said second load unit connected between the center terminal means and said second full voltage terminal means, and

means responsive to a selected difference in the voltage of said two battery supplies to connect said alternator to charge the battery supply having the lowest charge to equalize the charge of the two battery supplies.

19. The battery power supply system of claim 18 wherein said battery means is a lead-acid battery wherein the grids include antimony in an amount not substantially greater than 2 percent, or do not include antimony in any significant concentration.

20. The battery power supply system of claim 19 wherein said polyphase winding produces an alternating voltage having alternate half cycles of first polarity and alternate half cycles of a second polarity and said rectifying circuit includes a first group of controlled rectifier means connected to conduct the alternate half cycles of a first polarity of the output of said polyphase winding and a second group of controlled rectifier means connected to conduct the opposite half cycles of the second polarity of the output of said polyphase winding, the controlled rectifier means of each group being connected to each other, and a logic control means connected to said means responsive to a selected difference in the voltage of the low voltage battery supplies to separately charge each battery supply to maintain each battery supply at a selected minimum voltage.

21. The battery power supply system of claim 18 wherein said logic control means includes a switch means connected between said first and second load units and said center terminal means and operable to selectively connect said terminal means to said alternator to charge one of said two battery supplies.