Engine controller and control method

• US 20070021267A1
• Filed: 07/19/2006
• Published: 01/25/2007
• Est. Priority Date: 07/19/2005
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Kuroda, Daisuke, Obayashi, Kazuyoshi, Yamashita, Yukihiro, Tani, Keisuke
• Granted Patent: US 7,473,206 B2
• Time in Patent Office: Days
• US Class Current: 477/107
• CPC Class Codes: B60K 6/46 Series type
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• CPC Class Codes: B60W 10/30 including control of auxiliary equipment, e.g. air-conditioning compressors or oil pumps
• CPC Class Codes: B60W 20/11 using model predictive control [MPC] strategies, i.e. control methods based on models predicting performance utilising navigation and traffic information in the control strategy B60W20/12
• CPC Class Codes: B60W 2710/0644 Engine speed
• CPC Class Codes: B60W 2710/0666 Engine torque
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

An engine controller controls an engine, which drives a generator, an auxiliary device, and a vehicle. The generator generates electricity, and supplying the electricity to a battery and a plurality of current consumers. A generator controller controls the generator. An auxiliary device controller controls the auxiliary device. An electric power generation calculation unit calculates one of a requested power generation of the generator and a present power generation of the generator. An engine speed changing unit evaluates tendency of power generation on the basis of the one of the requested power generation and the present power generation. The engine speed changing unit requests increase or decreases in the engine speed when the engine speed changing unit determines the power generation to be inclined toward shortage or excess.

Claims

1. An engine speed controller provided to a vehicle energy control system that includes an engine controller, a generator controller, and an auxiliary device controller, the engine controller controlling an engine, which drives a generator, an auxiliary device, and a vehicle, the generator generating electricity and supplying the electricity to a battery and a plurality of current consumers, the generator controller controlling the generator, the auxiliary device controller controlling the auxiliary device, the engine speed controller performing a feedback control such that engine speed substantially coincides at a target value,

the engine speed controller comprising:

an electric power generation calculation unit that calculates one of a requested power generation and a present power generation of the generator; and

an engine speed changing unit that evaluates tendency of power generation on the basis of the one of the requested power generation and the present power generation,

wherein the engine speed changing unit requests increase in the engine speed when the engine speed changing unit determines the power generation to be inclined toward shortage, and

the engine speed changing unit requests decrease in the engine speed when the engine speed changing unit determines the power generation to be inclined toward excess.

2. The engine speed controller according to claim 1,

wherein the engine speed changing unit stores a relationship between the engine speed and the one of the requested power generation and the present power generation, and

the engine speed changing unit requests a change in the engine speed on the basis of the one of the requested power generation and the present power generation in reference to the relationship.

3. The engine speed controller according to claim 2,

wherein the engine speed changing unit requests increase in the engine speed when the requested electric power is large, and

the engine speed changing unit requests decrease in the engine speed when the requested electric power is small.

4. The engine speed controller according to claim 1,

wherein the engine speed changing unit calculates a first ratio of the one of the requested power generation and the present power generation to a present maximum generation of the generator, the present maximum generation corresponding to a present engine speed,

the engine speed changing unit requests increase in the engine speed when the first ratio is greater than a predetermined range, and

the engine speed changing unit requests decrease in the engine speed when the first ratio is less than the predetermined range.

5. The engine speed controller according to claim 4,

wherein the engine speed changing unit calculates a second ratio of the requested electric power to the maximum generation,

the engine speed changing unit requests increase in the engine speed when the second ratio is greater than a predetermined range, and

the engine speed changing unit requests decrease in the engine speed when the second ratio is less than the predetermined range.

6. The engine speed controller according to claim 3, wherein the requested electric power includes electric power demanded from the plurality of current consumers.

7. The engine speed controller according to claim 3, wherein the requested electric power includes electric power demanded from the plurality of current consumers and electric power for charging and discharging the battery.

8. The engine speed controller claim 6, further comprising:

a power generating apparatus that generates electricity and supplies the electricity to the battery and the plurality of current consumers,

wherein the requested electric power is one of;

a sum of the electric power demanded from the plurality of current consumers and electric power for charging and discharging the battery; and

a value calculated by subtracting electric power generated by the power generating apparatus from the electric power demanded from the plurality of current consumers.

9. The engine speed controller according to claim 1, further comprising:

an auxiliary device drive torque calculation unit that calculates one of a requested auxiliary device torque and a present auxiliary device torque of the auxiliary device,

wherein the engine speed changing unit evaluates tendency of one of engine torque and power generation on the basis of the one of the requested auxiliary device torque and the present auxiliary device torque of the auxiliary device and the one of the requested power generation and the present power generation,

the engine speed changing unit requests increase in the engine speed when the engine speed changing unit determines the one of the power generation and the engine torque to be inclined toward shortage, and

the engine speed changing unit requests decrease in the engine speed when the engine speed changing unit determines the one of the power generation and the engine torque to be inclined toward excess.

10. The engine speed controller according to claim 9, wherein the engine speed changing unit requests a change in the engine speed on the basis of a combination of any two of the following three:

request for a change in the engine speed, which is based on one of requested engine torque and present engine torque;

request for a change in the engine speed, which is based on one of requested power generation and present power generation; and

request for a change in the engine speed, which is based on one of requested auxiliary device torque and present auxiliary device torque.

11. The engine speed controller according to claim 1, wherein the engine speed changing unit restricts a change in the engine speed to be less than an upper limit when the engine is in an idling operation.

12. The engine speed controller according to claim 11, wherein the engine speed changing unit sets the upper limit according to a present gear ratio of a transmission device connected to the engine.

13. The engine speed controller according to claim 1,

wherein the engine controller calculates an allowable torque to be equal to or less than the engine torque,

the engine controller transmits the allowable torque to one of the generator controller and the auxiliary device controller,

the one of the generator controller and the auxiliary device controller consumes the engine torque within the allowable torque,

the engine controller controls the engine speed changing unit to change the engine speed according to the request of change in the engine speed,

the engine controller changes the allowable torque corresponding to the change in the engine speed, and

the engine controller transmits the change in the allowable torque to the one of the generator controller and the auxiliary device controller.

14. An engine speed controller provided to a vehicle energy control system that includes an engine controller, a generator controller, and an auxiliary device controller, the engine controller controlling an engine, which drives a generator, an auxiliary device, and a vehicle, the generator generating electricity and supplying the electricity to a battery and a plurality of current consumers, the generator controller controlling the generator, the auxiliary device controller controlling the auxiliary device, the engine speed controller performing a feedback control such that engine speed substantially coincides at a target value,

the engine speed controller comprising:

an engine torque calculation unit that calculates one of a requested engine torque and a present engine torque of the engine; and

an engine speed changing unit that evaluates tendency of engine torque on the basis of the one of the requested engine torque and the present engine torque,

wherein the engine speed changing unit requests increase in the engine speed when the engine speed changing unit determines the engine torque to be inclined toward shortage, and

the engine speed changing unit requests decrease in the engine speed when the engine speed changing unit determines the engine torque to be inclined toward excess.

15. The engine speed controller according to claim 14,

wherein the engine speed changing unit stores a relationship between the engine speed and the one of the requested engine torque and the present engine torque, and

the engine speed changing unit requests a change in the engine speed on the basis of the one of the requested engine torque and the present engine torque in reference to the relationship.

16. The engine speed controller according to claim 14,

wherein the engine speed changing unit calculates a ratio of the one of the requested engine torque and the present engine torque to a present maximum engine torque, the present maximum engine torque corresponding to a present engine speed,

the engine speed changing unit requests increase in the engine speed when the ratio is greater than a predetermined range, and

the engine speed changing unit requests decrease in the engine speed when the ratio is less than the predetermined range.

17. The engine speed controller according to claim 14, wherein the engine speed changing unit requests a change in the engine speed on the basis of a combination of any two of the following three:

request for a change in the engine speed, which is based on one of requested engine torque and present engine torque;

request for a change in the engine speed, which is based on one of requested power generation and present power generation; and

request for a change in the engine speed, which is based on one of requested auxiliary device torque and present auxiliary device torque.

18. The engine speed controller according to claim 14, wherein the engine speed changing unit restricts a change in the engine speed to be less than an upper limit when the engine is in an idling operation.

19. The engine speed controller according to claim 18, wherein the engine speed changing unit sets the upper limit according to a present gear ratio of a transmission device connected to the engine.

20. The engine speed controller according to claim 14,

wherein the engine controller calculates an allowable torque to be equal to or less than the engine torque,

the engine controller transmits the allowable torque to one of the generator controller and the auxiliary device controller,

the one of the generator controller and the auxiliary device controller consumes the engine torque within the allowable torque,

the engine controller controls the engine speed changing unit to change the engine speed according to the request of change in the engine speed,

the engine controller changes the allowable torque corresponding to the change in the engine speed, and

the engine controller transmits the change in the allowable torque to the one of the generator controller and the auxiliary device controller.

21. A control method comprising:

calculating one of a requested power generation and a present power generation performed using a generator driven by an engine for generating electricity;

evaluating tendency of power generation on the basis of the one of the requested power generation and the present power generation;

requesting increase in the engine speed when determining the power generation to be inclined toward shortage;

requesting decrease in the engine speed when determining the power generation to be inclined toward excess; and

operating the engine speed in accordance with the request of the engine speed.

22. The control method according to claim 21, further comprising:

storing a relationship between the engine speed and the one of the requested power generation and the present power generation; and

requesting a change in the engine speed on the basis of the one of the requested power generation and the present power generation in reference to the relationship.

23. The control method according to claim 22, further comprising:

requesting increase in the engine speed when the requested electric power is large; and

requesting decrease in the engine speed when the requested electric power is small.

24. The control method according to claim 21, further comprising:

calculating a first ratio of the one of the requested power generation and the present power generation to a present maximum generation of the generator, the present maximum generation corresponding to a present engine speed;

requesting increase in the engine speed when the first ratio is greater than a predetermined range; and

requesting decrease in the engine speed when the first ratio is less than the predetermined range.

25. The control method according to claim 24, further comprising:

calculating a second ratio of the requested electric power to the maximum generation;

requesting increase in the engine speed when the second ratio is greater than a predetermined range; and

requesting decrease in the engine speed when the second ratio is less than the predetermined range.

26. The control method according to claim 23, further comprising:

supplying electric power to a plurality of current consumers,

wherein the requested electric power includes electric power demanded from the plurality of current consumers.

27. The control method according to claim 23, further comprising:

supplying electric power to a plurality of current consumers; and

charging and discharging a battery,

wherein the requested electric power includes electric power demanded from the plurality of current consumers and electric power for charging and discharging a battery.

28. The control method claim 26, further comprising:

generating electricity for supplying the electricity to a battery and the plurality of current consumers; and

calculating the requested electric power by adding the electric power demanded from the plurality of current consumers to the electric power for charging and discharging the battery.

29. The control method according to claim 21, further comprising:

calculating one of a requested auxiliary device torque and a present auxiliary device torque of an auxiliary device;

evaluating tendency of one of engine torque and power generation on the basis of the one of the requested auxiliary device torque and the present auxiliary device torque of the auxiliary device and the one of the requested power generation and the present power generation;

requesting increase in the engine speed when determining the one of the power generation and the engine torque to be inclined toward shortage; and

requesting decrease in the engine speed when determining the one of the power generation and the engine torque to be inclined toward excess.

30. The control method according to claim 29, further comprising:

requesting a change in the engine speed on the basis of a combination of any two of the following three;

request for a change in the engine speed, which is based on one of requested engine torque and present engine torque;

request for a change in the engine speed, which is based on one of requested power generation and present power generation; and

request for a change in the engine speed, which is based on one of requested auxiliary device torque and present auxiliary device torque.

31. The control method according to claim 21, further comprising:

restricting a change in the engine speed to be less than an upper when the engine is in an idling operation.

32. The engine speed controller according to claim 31, further comprising:

setting the upper limit according to a present gear ratio of a transmission device connected to the engine.

33. The control method according to claim 29, further comprising:

calculating an allowable torque consumed in one of the generator and the auxiliary device within the engine torque;

changing the engine speed according to the request of change in the engine speed; and

changing the allowable torque corresponding to the change in the engine speed.

34. A control method comprising:

calculating one of a requested engine torque and a present engine torque of an engine that drives a generator for generating electricity;

evaluating tendency of engine torque on the basis of the one of the requested engine torque and the present engine torque;

requesting increase in the engine speed when determining the engine torque to be inclined toward shortage;

requesting decrease in the engine speed when determining the engine torque to be inclined toward excess; and

operating the engine speed in accordance with the request of the engine speed.

35. The control method according to claim 34, further comprising:

storing a relationship between the engine speed and the one of the requested engine torque and the present engine torque; and

requesting a change in the engine speed on the basis of the one of the requested engine torque and the present engine torque in reference to the relationship.

36. The control method according to claim 34, further comprising:

calculating a ratio of the one of the requested engine torque and the present engine torque to a present maximum engine torque, the present maximum engine torque corresponding to a present engine speed;

requesting increase in the engine speed when the ratio is greater than a predetermined range; and

requesting decrease in the engine speed when the ratio is less than the predetermined range.

37. The control method according to claim 34, further comprising:

requesting a change in the engine speed on the basis of a combination of any two of the following three;

request for a change in the engine speed, which is based on one of requested engine torque and present engine torque;

request for a change in the engine speed, which is based on one of requested power generation and present power generation; and

request for a change in the engine speed, which is based on one of requested auxiliary device torque and present auxiliary device torque.

38. The control method according to claim 34, further comprising:

requesting a change in the engine speed to be less than an upper limit when the engine is in an idling operation.

39. The control method according to claim 38, further comprising:

setting the upper limit according to a present gear ratio of a transmission device connected to the engine.

40. The control method according to claim 34, further comprising:

calculating an allowable torque consumed in one of the generator and an auxiliary device within the engine torque;

changing the engine speed according to the request of change in the engine speed; and

changing the allowable torque corresponding to the change in the engine speed.