Control apparatus for selectively controlling output current and output voltage of electric generator

• US 20070052243A1
• Filed: 08/23/2006
• Published: 03/08/2007
• Est. Priority Date: 09/07/2005
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Kuroda, Daisuke, Obayashi, Kazuyoshi, Shimoyama, Takeshi, Tani, Keisuke, Yamashita, Yukihiro, Tanaka, Katsunori
• Granted Patent: US 7,459,801 B2
• Time in Patent Office: Days
• US Class Current: 290/40.B
• CPC Class Codes: H02P 9/48 Arrangements for obtaining a constant output value at varying speed of the generator, e.g. on vehicle H02P9/04 - H02P9/46 take precedence

Abstract

An electric generator control apparatus of a vehicle sets respective target values of output voltage and output current for the electric generator of the vehicle, and selectively establishes a voltage control mode for holding the generator output voltage at the target voltage or a current control mode for holding the generator output current at the target current, with the mode selection and the setting of target values being performed based on criteria such as the level of charge of the vehicle battery, the electrical load of the vehicle equipment, etc.

Claims

1. An electric generator control apparatus, for controlling an electric generator that is driven by an internal combustion engine and that supplies a charging current to a battery, wherein said electric generator control apparatus comprises:

voltage control means for setting a target voltage value and for controlling an output voltage of said electric generator to maintain said target voltage value;

current control means for setting a target current value and for controlling an output current of said electric generator to maintain said target current value; and

control mode changeover means for selectively establishing a voltage control mode in which said output voltage of said electric generator is controlled by said voltage control means to maintain said target voltage value and a current control mode in which said output current of said electric generator is controlled by said current control means to maintain said target current value.

2. An electric generator control apparatus according to claim 1, wherein internal combustion engine and electrical generator apparatus are installed in a motor vehicle, and wherein said mode changeover means performs said changeover between said voltage control mode and said current control mode in accordance with at least one of an operating condition of said internal combustion engine and a running condition of said vehicle.

3. An electric generator control apparatus according to claim 1, wherein said mode changeover means performs said changeover between said voltage control mode and said current control mode in accordance with a level of charge of said battery.

4. An electric generator control apparatus according to claim 1, wherein said mode changeover means performs said changeover between said voltage control mode and said current control mode in accordance with whether or not deterioration of said battery exceeds a predetermined extent.

5. An electric generator control apparatus according to claim 1, wherein said mode changeover means performs said changeover between said voltage control mode and said current control mode in accordance with an ambient environmental condition.

6. An electric generator control apparatus according to claim 5, wherein;

said ambient environmental condition is an external air temperature;

said electric generator control apparatus is coupled to temperature sensor means, for receiving data indicative of said external air temperature, and comprises means for judging said external air temperature; and

when said external air temperature is judged to below a predetermined threshold value, said mode changeover means establishes said voltage control mode, and said voltage control means sets said target voltage at a value that has been predetermined as corresponding to a condition of the external air temperature being below said threshold value.

7. An electric generator control apparatus according to claim 1, wherein said electric generator control apparatus is coupled to receive data indicative of diagnosis results obtained by a failure diagnosis system, and wherein said mode changeover means performs said changeover between said voltage control mode and said current control mode in accordance with said diagnosis results.

8. An electric generator control apparatus according to claim 1, wherein:

said electric generator control apparatus is coupled to receive data indicative of diagnosis results obtained by a failure diagnosis system;

said electric generator comprises autonomous control means operable for autonomously controlling said output voltage of said electric generator to a predetermined fixed value; and

in response to predetermined diagnosis results being obtained by said failure diagnosis system, said mode changeover means establishes an autonomous control mode in which said autonomous control means autonomously controls said output voltage of said electric generator.

9. An electric generator control apparatus according to claim 1, wherein said electric generator control apparatus is coupled for communication with a control apparatus of said internal combustion engine, and wherein said electric generator control apparatus is adapted to:

detect a condition whereby a maximum level of output electrical power that can be produced by said electric generator under a current operating status of said internal combustion engine does not attain a required level of electrical power, and when said condition is detected,

transmit to said control apparatus of said internal combustion engine a command for producing a change in said operating status of said internal combustion engine.