Vehicular electric power generation control apparatus

• US 20040053083A1
• Filed: 09/04/2003
• Published: 03/18/2004
• Est. Priority Date: 09/18/2002
• Status: Active Grant

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Yajima, Satoshi, Kobayashi, Kazuhira
• Granted Patent: US 6,844,634 B2
• Time in Patent Office: Days
• US Class Current: 429/9
• CPC Class Codes: B60L 58/20 having different nominal voltages
• CPC Class Codes: B60R 16/03 for supply of electrical power to vehicle subsystems or for circuit arrangements for charging batteries H02J7/00
• CPC Class Codes: H02J 2310/46 for ICE-powered road vehicles
• CPC Class Codes: H02J 7/1423 with multiple batteries
• CPC Class Codes: H02J 7/1446 in response to parameters of a vehicle
• 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 lithium ion battery 11 is connected in parallel to a lead acid battery 9 charged with electric power generated by a generator 2. The lithium ion battery 11 has internal resistance smaller than internal resistance of the lead acid battery 9 and being charged with the electric power generated by the generator 2. An ECM 6 supplies an electric power generation command value based on a running state of a vehicle, and an ECU 7 controls the generator 2 for electric power generation by supplying the electric power generation command voltage to the generator 2.

Claims

1. A vehicular electric power generation control apparatus, comprising:

a generator driven by an engine and controlled for electric power generation based on an electric power generation command voltage;

an aqueous secondary battery charged with electric power generated by the generator;

a non-aqueous secondary battery connected in parallel to the aqueous secondary battery, the non-aqueous secondary battery having internal resistance smaller than internal resistance of the aqueous secondary battery and being charged with the electric power generated by the generator;

a first voltage detecting unit for detecting a voltage of the aqueous secondary battery;

a second voltage detecting unit for detecting a voltage of the non-aqueous secondary battery;

a revolution number detecting unit for detecting a revolution number of the engine;

a vehicle speed detecting unit for detecting a vehicle speed;

an electric power generation command value computing unit for computing an electric power generation command value based on the revolution number of the engine and based on the vehicle speed detected by the vehicle speed detecting unit, the revolution number being detected by the revolution number detecting unit; and

an electric power generation command voltage supplying unit for supplying, to the generator, an electric power generation command voltage based on the voltage of the aqueous secondary battery, the voltage of the aqueous secondary battery being detected by the first voltage detecting unit, based on the voltage of the non-aqueous secondary battery, the voltage of the non-aqueous secondary battery being detected by the second voltage detecting unit, and based on the electric power generation command value computed by the electric power generation command value computing unit.

2. The vehicular electric power generation control apparatus according to claim 1,

wherein the electric power generation command voltage is an electric power generation command voltage for setting the generator in an electric power generation state when the voltage of the non-aqueous secondary battery, the voltage being detected by the second voltage detecting unit, is equal to/less than a first threshold value, and is an electric power generation command voltage for setting the generator in a non-electric power generation state when the voltage of the non-aqueous secondary battery becomes equal to/more than a second threshold value larger than the first threshold value.

3. The vehicular electric power generation control apparatus according to claim 1, further comprising:

a load driven by being supplied with electric power from at least one of the generator, the aqueous secondary battery and the non-aqueous secondary battery;

a breakdown detecting unit for detecting a breakdown of the non-aqueous secondary battery based on the voltage of the non-aqueous secondary battery, the voltage being detected by the second voltage detecting unit; and

a connection control unit for isolating the non-aqueous secondary battery from the load and the generator when the breakdown of the non-aqueous secondary battery is detected by the breakdown detecting unit.

4. The vehicular electric power generation control apparatus according to claim 3, further comprising a notifying unit for notifying of the breakdown of the non-aqueous secondary battery,

wherein the breakdown of the non-aqueous secondary battery is notified by the notifying unit when the breakdown of the non-aqueous secondary battery is detected by the breakdown detecting unit.

5. A vehicular electric power generation control apparatus, comprising:

a generator driven by an engine and controlled for electric power generation based on an electric power generation command voltage;

an aqueous secondary battery charged with electric power generated by the generator;

a non-aqueous secondary battery connected in parallel to the aqueous secondary battery, the non-aqueous secondary battery having internal resistance smaller than internal resistance of the aqueous secondary battery and being charged with the electric power generated by the generator;

first voltage detecting means for detecting a voltage of the aqueous secondary battery;

second voltage detecting means for detecting a voltage of the non-aqueous secondary battery;

revolution number detecting means for detecting a revolution number of the engine;

vehicle speed detecting means for detecting a vehicle speed;

electric power generation command value computing means for computing an electric power generation command value based on the revolution number of the engine and based on the vehicle speed detected by the vehicle speed detecting means, the revolution number being detected by the revolution number detecting means; and

electric power generation command voltage supplying means for supplying, to the generator, an electric power generation command voltage based on the voltage of the aqueous secondary battery, the voltage of the aqueous secondary battery being detected by the first voltage detecting means, based on the voltage of the non-aqueous secondary battery, the voltage of the non-aqueous secondary battery being detected by the second voltage detecting means, and based on the electric power generation command value computed by the electric power generation command value computing means.

6. A vehicular electric power generation control method, comprising:

preparing a generator driven by an engine and controlled for electric power generation based on an electric power generation command voltage, an aqueous secondary battery charged with electric power generated by the generator, and a non-aqueous secondary battery connected in parallel to the aqueous secondary battery, the non-aqueous secondary battery having internal resistance smaller than internal resistance of the aqueous secondary battery and being charged with the electric power generated by the generator;

detecting a voltage of the aqueous secondary battery;

detecting a voltage of the non-aqueous secondary battery;

detecting a revolution number of the engine;

detecting a vehicle speed;

computing an electric power generation command value based on the revolution number of the engine and based on the vehicle speed; and

supplying to the generator an electric power generation command voltage based on the voltage of the aqueous secondary battery, the voltage of the non-aqueous secondary battery, and the electric power generation command value.