Field transient suppression system and method

• US 20100079117A1
• Filed: 09/30/2008
• Published: 04/01/2010
• Est. Priority Date: 09/30/2008
• Status: Active Grant

• Current Assignee: C.E. Niehoff & Co.
• Original Assignee: C.E. Niehoff & Co.
• Inventors: Bekiarov, Stoyan Borissov
• Granted Patent: US 8,289,005 B2
• Time in Patent Office: Days
• US Class Current: 322/28
• CPC Class Codes: H02J 7/1438 in combination with power supplies for loads other than batteries
• CPC Class Codes: H02J 7/1492 by means of controlling devices between the generator output and the battery
• CPC Class Codes: H02P 9/102 for limiting effects of transients
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/92 Energy efficient charging or discharging systems for batteries, ultracapacitors, supercapacitors or double-layer capacitors specially adapted for vehicles

Abstract

A vehicle electrical system comprises a generator, voltage regulator, electrical energy source, and control device. The generator provides electrical current to one or more electrical loads. Voltage transients from electrical load variations are suppressed by storing electrical energy of the field coil of the generator in the electrical energy source, and by proving electrical energy from the electrical energy source to the field coil. The control device comprises a controller and a charging module operative to maintain the voltage of the electrical energy source at a predetermined voltage that is above the regulation voltage so as to reduce the generator output voltage transients due to sudden variations in the one or more electrical loads.

Claims

1. A vehicle electrical system comprising:

(a) a generator comprising a field coil and one or more stator windings interacting with changing magnetic flux produced by field current through said field coil and providing electrical current to one or more electrical loads;

(b) a voltage regulator operative to maintain an output voltage of the generator at a regulation voltage by varying the field current;

(c) an electrical energy source operative to one of store and provide electrical energy of the field coil; and

(d) a control device configured to maintain a voltage of the electrical energy source at a predetermined voltage above the regulation voltage, via a charging module, so as to reduce the generator output voltage transients due to sudden variations in the one or more electrical loads.

2. The system of claim 1, wherein the control device is configured to charge the electrical energy source, via the charging module, when the voltage of the electrical energy source is below the predetermined voltage.

3. The system of claim 1, wherein the control device is configured to maintain the charge of the electrical energy source, via the charging module, when the voltage of the electrical energy source is at the predetermined voltage.

4. The system of claim 1, wherein the control device is configured to discharge the electrical energy source, via the charging module, when the voltage of the electrical energy source is above the predetermined voltage.

5. The system of claim 1, wherein the control device is further configured to one of store the electrical energy of the field coil in the electrical energy source and provide the electrical energy in the electrical energy source to the field coil, via the charging module, when the output voltage of the generator differs from the regulation voltage.

6. A vehicle electrical system comprising:

(a) a generator comprising a field coil and one or more stator windings interacting with changing magnetic flux produced by field current through said field coil and providing electrical current to one or more electrical loads;

(b) a voltage regulator operative to maintain an output voltage of the generator at a regulation voltage by varying the field current;

(c) an electrical energy source operative to one of store and provide electrical energy of the field coil; and

(d) a control device configured to;

(i) maintain a voltage of the electrical energy source at a predetermined voltage above the regulation voltage, via a charging module; and

(ii) one of store the electrical energy of the field coil in the electrical energy source and provide the electrical energy in the electrical energy source to the field coil, via the charging module, when the output voltage of the generator differs from the regulation voltage, so as to reduce the generator output voltage transients due to sudden variations in the one or more electrical loads.

7. A control device, coupled with a generator, a voltage regulator, and an electrical energy source, said generator comprising a field coil and one or more stator windings interacting with changing magnetic flux produced by field current through said field coil and providing electrical current to one or more electrical loads, said voltage regulator operative to maintain an output voltage of the generator at a regulation voltage by varying the field current, said electrical energy source operative to one of store and provide electrical energy of the field coil, said control device comprising:

(a) a charging module; and

(b) a controller, coupled with the generator, electrical energy source, and charging module;

wherein the controller is configured to;

(i) measure a voltage of the electrical energy source, via a first sense line; and

(ii) apply one or more control signals to the charging module, via one or more control lines to maintain the voltage of the electrical energy source at a predetermined voltage that is above the regulation voltage, so as to reduce the generator output voltage transients due to sudden variations in the one or more electrical loads.

8. The control device of claim 7, wherein the charging module comprises at least one of a switch, a diode, and a resistor, and wherein the electrical energy source is a capacitor.

9. The control device of claim 7, wherein the charging module comprises a first and a second switch and wherein the controller is configured to switch off the first switch and switch on the second switch when the voltage of the electrical energy source is below the predetermined voltage.

10. The control device of claim 7, wherein the charging module comprises a first and a second switch and wherein the controller is configured to switch on the first switch and switch off the second switch when the voltage of the electrical energy source is at the predetermined voltage.

11. The control device of claim 7, wherein the charging module comprises a first and a second switch and wherein the controller is configured to switch on the first and second switch when the voltage of the electrical energy source is above the predetermined voltage.

12. The control device of claim 7, wherein the charging module comprises a first and a second switch and wherein the controller is further configured to measure the output voltage of the generator, via a second sense line, and to switch on at least one of the first and second switch when the output voltage of the generator differs from the regulation voltage.

13. The control device of claim 7, wherein the charging module comprises a switch, a diode, and a resistor and wherein the controller is configured to switch off the switch when the voltage of the electrical energy source is below the predetermined voltage.

14. The control device of claim 7, wherein the charging module comprises a switch, a diode, and a resistor and wherein the controller is configured to switch on the switch when the voltage of the electrical energy source is at the predetermined voltage.

15. The control device of claim 7, wherein the charging module comprises a switch, a diode, and a resistor and wherein the controller is further configured to measure the output voltage of the generator, via a second sense line, and to switch off the switch when the output voltage of the generator differs from the regulation voltage.

16. A voltage transient suppression circuit in a voltage regulator for a generator, said generator comprising a field coil, said circuit comprising:

(a) a first switch operative to switch on/off electrical current flow between a positive side of the field coil and a positive side of a voltage source;

(b) a second switch operative to switch on/off the electrical current flow from a negative side of the field coil to a negative side of the voltage source;

(c) a first diode operative to direct the electrical current from the negative side of the field coil to the positive side of the voltage source; and

(d) a second diode operative to direct the electrical current from the negative side of the voltage source to the positive side of the field coil;

wherein the circuit suppresses voltage transients of an output voltage of the generator when the voltage regulator switches off both the first and second switches.

17. A method for controlling a vehicle electrical system, said system comprising:

(a) a generator comprising a field coil and one or more stator windings interacting with changing magnetic flux produced by field current through said field coil and providing electrical current to one or more electrical loads;

(b) a voltage regulator operative to maintain an output voltage of the generator at a regulation voltage by varying the field current;

(c) an electrical energy source operative to one of store and provide electrical energy of the field coil;

said method, comprising;

(i) maintaining a voltage of the electrical energy source at a predetermined voltage above the regulation voltage, via a charging module, so as to reduce the generator output voltage transients due to sudden variations in the one or more electrical loads.

18. The method of claim 17, wherein (i) comprises charging the electrical energy source, via the charging module, when the voltage of the electrical energy source is below the predetermined voltage.

19. The method of claim 17, wherein (i) comprises maintaining the charge of the electrical energy source, via the charging module, when the voltage of the electrical energy source is at the predetermined voltage.

20. The method of claim 17, wherein (i) comprises discharging the electrical energy source, via the charging module, when the voltage of the electrical energy source is above the predetermined voltage.

21. The method of claim 17, further comprising:

(ii) one of storing the electrical energy of the field coil in the electrical energy source and providing the electrical energy in the electrical energy source to the field coil, via the charging module, when the output voltage of the generator differs from the regulation voltage.

22. A method for controlling a generator coupled with a voltage regulator and an electrical energy source, said generator comprising a field coil and one or more stator windings interacting with changing magnetic flux produced by field current through said field coil and providing electrical current to one or more electrical loads, said voltage regulator operative to maintain an output voltage of the generator at a regulation voltage by varying the field current, said electrical energy source operative to one of store and provide electrical energy of the field coil, said method comprising:

(i) measuring a voltage of the electrical energy source, via a first sense line; and

(ii) applying one or more control signals to a charging module, via one or more control lines, to maintain the voltage of the electrical energy source at a predetermined voltage that is above the regulation voltage, so as to reduce the generator output voltage transients due to sudden variations in the one or more electrical loads.

23. The method of claim 22, wherein the charging module comprises at least one of a switch, a diode, and a resistor, and wherein the electrical energy source is a capacitor.

24. The method of claim 22, wherein the charging module comprises a first and a second switch and wherein (ii) comprises:

(a) switching off the first switch; and

(b) switching on the second switch;

when the voltage of the electrical energy source is below the predetermined voltage.

25. The method of claim 22, wherein the charging module comprises a first and a second switch and wherein (ii) comprises:

(a) switching on the first switch; and

(b) switching off the second switch;

when the voltage of the electrical energy source is at the predetermined voltage.

26. The method of claim 22, wherein the charging module comprises a first and a second switch and wherein (ii) comprises:

(a) switching on the first switch; and

(b) switching on the second switch;

when the voltage of the electrical energy source is above the predetermined voltage.

27. The method of claim 22, wherein the charging module comprises a first and a second switch and wherein the method further comprises:

(iii) measuring the output voltage of the generator, via a second sense line;

wherein (ii) comprises switching on at least one of the first and second switch when the output voltage of the generator differs from the regulation voltage.

28. The method of claim 22, wherein the charging module comprises a switch, a diode, and a resistor and wherein (ii) comprises switching off the switch when the voltage of the electrical energy source is below the predetermined voltage.

29. The method of claim 22, wherein the charging module comprises a switch, a diode, and a resistor and wherein (ii) comprises switching on the switch when the voltage of the electrical energy source is at the predetermined voltage.

30. The method of claim 22, wherein the charging module comprises a switch, a diode, and a resistor and wherein the method further comprises:

(iii) measuring the output voltage of the generator, via a second sense line;

wherein (ii) comprises switching off the switch when the output voltage of the generator differs from the regulation voltage.

31. A method for controlling a generator coupled with a voltage regulator and an electrical energy source, said generator comprising a field coil and one or more stator windings interacting with changing magnetic flux produced by field current through said field coil and providing electrical current to one or more electrical loads, said voltage regulator operative to maintain an output voltage of the generator at a regulation voltage by varying the field current, said electrical energy source operative to one of store and provide electrical energy of the field coil, said method comprising:

(i) measuring a voltage of the electrical energy source, via a first sense line;

(ii) measuring the output voltage of the generator, via a second sense line;

(iii) applying one or more control signals to a charging module, via one or more control lines, to;

(a) maintain the voltage of the electrical energy source at a predetermined voltage that is above the regulation voltage; and

(b) one of store the electrical energy of the field coil in the electrical energy source and provide the electrical energy in the electrical energy source to the field coil, via the charging module, when the output voltage of the generator differs from the regulation voltage, so as to reduce the generator output voltage transients due to sudden variations in the one or more electrical loads.

32. A method for suppressing voltage transients via a voltage transient suppression circuit in a voltage regulator for a generator, said generator comprising a field coil, said circuit comprising a first switch, a second switch, a first diode, and a second diode:

said method comprising

(a) switching on/off electrical current flow between a positive side of the field coil and a positive side of a voltage source, via a first switch;

(b) switching on/off the electrical current flow from a negative side of the field coil to a negative side of the voltage source, via a second switch;

(c) directing the electrical current from the negative side of the field coil to the positive side of the voltage source, via a first diode; and

(d) directing the electrical current from the negative side of the voltage source to the positive side of the field coil, via a second diode;

wherein the circuit suppresses voltage transients of an output voltage of the generator when the voltage regulator switches off both the first and second switches.