Alternator regulation circuit having parallel field coil current re-circulation
First Claim
Patent Images
1. An apparatus, comprising:
- an alternator field coil;
a driver coupled to said alternator field coil to provide an excitation current thereto;
a recirculation circuit coupled to said alternator field coil, said recirculation circuit including a unidirectional current device and a current sensing device electrically coupled in series; and
wherein said driver is electrically coupled between a first electrical power supply node and said field coil, and said recirculation circuit is electrically coupled between said driver and a second electrical power supply node.
4 Assignments
0 Petitions
Accused Products
Abstract
Among the embodiments of the present invention is an apparatus that includes an alternator field coil, a driver coupled to the alternator field coil to provide excitation current thereto, and a recirculation circuit coupled to the alternator field coil. The recirculation circuit includes a unidirectional current device and a current sensing device electrically coupled in series. The driver is electrically coupled between a first electrical power supply node and the field coil, and the recirculation circuit is electrically coupled between the driver and a second electrical power supply node.
-
Citations
26 Claims
-
1. An apparatus, comprising:
-
an alternator field coil;
a driver coupled to said alternator field coil to provide an excitation current thereto;
a recirculation circuit coupled to said alternator field coil, said recirculation circuit including a unidirectional current device and a current sensing device electrically coupled in series; and
wherein said driver is electrically coupled between a first electrical power supply node and said field coil, and said recirculation circuit is electrically coupled between said driver and a second electrical power supply node. - View Dependent Claims (2, 3, 4)
-
-
5. An apparatus, comprising:
-
an alternator including a field coil;
a driver to provide excitation current to said field coil; and
a recirculation circuit electrically coupled in parallel with said field coil, said recirculation circuit including a current sensing device electrically coupled in series with a unidirectional current device. - View Dependent Claims (6, 7, 8, 9, 10)
circuitry to sense voltage output by said alternator to regulate operation of said driver as a function of said voltage output; and
a differential amplifier to provide a current level signal, said differential amplifier including a pair of differential inputs coupled across said current sensing device.
-
-
10. The apparatus of claim 9, further comprising a control module responsive to the current level signal.
-
11. An apparatus, comprising:
-
an alternator including a field coil; and
circuitry including a switching device, a current sensing device, and a unidirectional current device, said unidirectional current device being electrically coupled in series with said current sensing device and being operable to route more electric current through said current sensing device during an inactive state of said switching device than during an active state of said switching device. - View Dependent Claims (12, 13, 14, 15)
an integrated circuit electrically coupled to said resistor and said transistor, said integrated circuit including circuitry to selectively change state of said transistor to modulate excitation current supplied to said field coil and a pair of differential inputs coupled across said resistor to provide a current level signal; and
a control module responsive to the current level signal, said control module being coupled to said integrated circuit.
-
-
16. A method, comprising:
-
providing circuitry including a switching device, a current sensing device, and a unidirectional device;
controlling electrical current flow through an alternator field coil with the circuitry; and
routing more electric current through the unidirectional current device and the current sensing device from the alternator field coil during one state of the switching device than during a different state of the switching device. - View Dependent Claims (17, 18, 19)
sensing a voltage level corresponding to a voltage supply output provided with the alternator field coil; and
generating the signal with circuitry responsive to said voltage level.
-
-
18. The method of claim 17, wherein the transistor is nonconductive during the one state and the transistor is conductive during the different state.
-
19. The method of claim 16, wherein said routing includes:
-
flowing current in a recirculation current path through the alternator field coil, the unidirectional current device, and the current sensing device during the one state of the switching device; and
flowing current in an excitation current path through the switching device and the alternator field coil during the different state of the switching device.
-
-
20. A method, comprising:
-
establishing a first state of a driver to direct electric current flow through an alternator field coil along a first path;
changing the driver from the first state to a second state to route electrical current flowing through the alternator field coil along a second path different than the first path; and
sensing different nonzero levels of an electric current with a current sensing device in the second path that is not included in the first path. - View Dependent Claims (21, 22, 23, 24, 25, 26)
determining a field coil current level signal from said sensing; and
providing the field coil current level signal to a control module.
-
-
23. The method of claim 22, wherein said determining includes generating the field coil current level signal with a differential amplifier.
-
24. The method of claim 20, wherein the current sensing device includes a current sensing resistor and said switching device includes a transistor.
-
25. The method of claim 24, further comprising providing a diode in the second path to selectively direct current through the current sensing device.
-
26. The method of claim 24, which further includes determining a peak current through the alternator field coil based on said sensing.
Specification