Device to provide a regulated power supply for in-cylinder ionization detection by using the ignition coli fly back energy and two-stage regulation

• US 7,137,385 B2
• Filed: 06/11/2003
• Issued: 11/21/2006
• Est. Priority Date: 11/01/2002
• Status: Active Grant

• Current Assignee: Visteon Global Technologies Incorporated (Visteon Corporation)
• Original Assignee: Visteon Global Technologies Incorporated (Visteon Corporation)
• Inventors: Newton, Stephen J.
• Primary Examiner(s): Wolfe, Willis R.
• Assistant Examiner(s): Hoang, Johnny H.
• Application Number:
  US10/458,712
• Publication Number:
  US 20040084035A1
• Time in Patent Office: 1,259 Days
• Field of Search: 123/618, 123/620, 123/630, 123/655, 123/198.DC, 123/198.D, 123/198.DA, 123/652, 73/350.8, 324/388, 324/399, 324/378, 324/379
• US Class Current: 123/630
• CPC Class Codes: F01N 2430/00 Influencing exhaust purification, e.g. starting of catalytic reaction, filter regeneration, or the like, by controlling engine operating characteristics
• CPC Class Codes: F02D 2041/285 the sensor having a signal processing unit external to the engine control unit
• CPC Class Codes: F02M 26/01 Internal exhaust gas recirculation, i.e. wherein the residual exhaust gases are trapped in the cylinder or pushed back from the intake or the exhaust manifold into the combustion chamber without the use of additional passages
• CPC Class Codes: F02P 17/12 Testing characteristics of the spark, ignition voltage or current testing of sparking plugs H01T13/60
• CPC Class Codes: F02P 2017/125 Measuring ionisation of combustion gas, e.g. by using ignition circuits
• CPC Class Codes: F02P 2017/128 for knock detection
• CPC Class Codes: F02P 3/045 for control of the dwell or anti dwell time
• CPC Class Codes: F02P 3/0453 Opening or closing the primary coil circuit with semiconductor devices
• CPC Class Codes: F02P 3/051 Opening or closing the primary coil circuit with semiconductor devices
• CPC Class Codes: F02P 5/1506 with particular means during starting
• CPC Class Codes: F02P 5/1514 with means for optimising the use of registers or of memories, e.g. interpolation
• CPC Class Codes: F02P 5/1523 with particular laws of return to advance, e.g. step by step, differing from the laws of retard
• CPC Class Codes: F02P 5/1526 with means for taking into account incorrect functioning of the pinking sensor or of the electrical means
• CPC Class Codes: G01L 23/225 circuit arrangements therefor
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

This feature of the present invention comprises a method and apparatus that provides a regulated power supply for in-cylinder ionization detection by harvesting the excess ignition coil leakage and magnetizing energy immediately following the turn off of the ignition coil IGBT. It uses an additional energy storage capacitor which replaces a first capacitor as the primary energy storage device. Thus, this feature of the present invention uses a two step method for charging the ionization detection circuit, as opposed to just one stage. The second capacitor is charged first, typically up to 400 Volts DC, and is then used as a reservoir to charge the first capacitor.

Claims

1. A method of providing a regulated power supply for in-cylinder ionization detection, comprising the steps of:

harvesting an ignition coil leakage energy from a primary winding of an ignition coil; and

harvesting magnetizing energy from said primary winding of said ignition coil following turn off of said ignition coil.

2. The method according to claim 1 wherein said step of harvesting an ignition coil leakage energy comprises the steps of:

turning a switch off;

reversing a transformer primaiy voltage;

forward biasing a diode; and

charging a capacitor.

3. The method according to claim 1 wherein said step of harvesting an ignition coil leakage energy further comprises the step of capturing energy stored in a transformer leakage inductance and using it as an energy source for an ionization electronics circuit.

4. The method according to claim 1 wherein said step of harvesting an ignition coil leakage energy further comprises the step of diverting leakage energy into a high voltage capacitor, whereby dissipation and resulting heaxing of a primary IGBT is reduced.

5. The method according to claim 2 wherein said step of harvesting an ignition coil leakage energy thriher comprises the step of storing energy at 350 to 400 volts in a high voltage capacitor, whereby a smaller capacitor can be used to store energy.

6. The method according to claim 2 wherein said step of harvesting an ignition coil leakage energy further comprises the steps of:

firing a spark plug;

collapsing a secondaxy voltage of said transformer;

igniting an air-fuel mixture;

collapsing a primary voltage of said transformer; and

reverse biasing said diode.

7. The method according to claim 2 further comprising the step of supplying current to at least one ionization circuit.

8. The method according to claim 2 further comprising the step of supplying current to a second capacitor.

9. The method according to claim 6 further comprising the step of supplying current to at least one ionization circuit.

10. The method according to claim 6 further comprising the step of supplying current to a second capacitor.

11. The method according to claim 7 wherein said step of supplying current comprises bleeding current from said capacitor to said at least one ionization current.

12. The method according to claim 8 wherein said step of supplying current comprises bleeding current from said capacitor to said second capacitor.

13. The method according to claim 9 wherein said step of supplying current comprises bleeding current from said capacitor to said at least one ionization current.

14. The method according to claim 10 wherein said step of supplying current comprises bleeding current from said capacitor to said second capacitor.