Predictive auxiliary load management (PALM) control apparatus and method

• US 20070272173A1
• Filed: 05/15/2007
• Published: 11/29/2007
• Est. Priority Date: 05/15/2006
• Status: Active Grant

• Current Assignee: Daimler Trucks North America LLC (Mercedes-Benz Group AG)
• Original Assignee: Freightliner Limited (Genesee & Wyoming Incorporated)
• Inventors: Reckels, Dieter, Paun, Cristin, Duraiswamy, Shiva
• Granted Patent: US 7,424,868 B2
• Time in Patent Office: Days
• US Class Current: 123/41.110
• CPC Class Codes: F01P 2025/62 Load
• CPC Class Codes: F01P 2025/64 Number of revolutions
• CPC Class Codes: F01P 2025/66 Vehicle speed
• CPC Class Codes: F01P 7/00 Controlling of coolant flow
• CPC Class Codes: F01P 7/048 using electrical drives
• CPC Class Codes: F01P 7/164 by varying pump speed
• CPC Class Codes: F01P 7/167 by adjusting the pre-set temperature according to engine parameters, e.g. engine load, engine speed
• CPC Class Codes: G16Z 99/00 Subject matter not provided for in other main groups of this subclass

Abstract

An improved vehicle cooling system is disclosed having the capability of controlling various thermal components of the system to effectively control the heating and cooling of an engine of the vehicle based on instantaneous vehicle and ambient conditions and also based upon predictive conditions. These predictive conditions can include information about the upcoming terrain of the route along which the vehicle will travel.

Claims

1. A vehicle comprising:

an engine;

a vehicle engine cooling system for receiving and circulating liquid coolant to cool the engine;

a vehicle fan operable to assist the cooling of liquid coolant circulating in the vehicle engine cooling system;

the vehicle engine cooling system comprising a coolant pump operable to circulate liquid coolant within the vehicle engine cooling system with the quantity of coolant being circulated being variable and responsive to coolant pump control signals, the the vehicle engine cooling system also comprising a thermostat operable to control the flow of coolant being circulated by the coolant pump through the cooling system, with the extent that the thermostat is open to permit the flow of coolant in the cooling system being variable and responsive to thermostat control signals; and

wherein the coolant pump and thermostat control signals are determined predictively for a prediction horizon so as to minimize at least one of the following;

(a) energy consumed by the coolant pump;

(b) variations in coolant temperature; and

(c) fan activation as the vehicle travels along a route that corresponds to the prediction horizon.

2. An apparatus according to claim 1 wherein the coolant pump and thermostat control signals are determined so as to minimize at least the sum of all three of:

(a) energy consumed by the coolant pump;

(b) variations in coolant temperature; and

(c) fan activation over the prediction horizon.

3. An apparatus according to claim 2 wherein the coolant pump control signals and thermostat control signals are determined for plural discrete segments of the prediction horizon so as to minimize at least the sum of:

(a) energy consumed by the coolant pump;

(b) variations in coolant temperature; and

(c) fan activation for each of the discrete segments.

4. An apparatus according to claim 3 wherein the coolant pump and thermostat control signals are determined according to a search space for coolant temperature that, at an upper temperature level, is no greater than Tc_max, wherein Tc_max is a maximum coolant temperature in the search space and is below a fan activation coolant temperature at which a vehicle fan would be activated, the search space having a lower temperature level Tc_min, the coolant pump and thermostat control signals being determined such that temperature of the coolant falls within the search space during at least certain segments of the prediction horizon.

5. A method of operating a vehicle coolant system comprising:

determining a prediction horizon for which elevation information is known; and

determining coolant pump and thermostat control signals for use in controlling a coolant pump of the coolant system and a thermostat of the coolant system as the vehicle travels along a route that follows the prediction horizon, the coolant pump and thermostat control signals being determined so as to minimize at least one of the following;

(a) energy consumed by the coolant pump;

(b) variations in coolant temperature; and

(c) fan activation.

6. A method according to claim 5 wherein the coolant pump and thermostat control signals are determined so as to minimize at least the sum of all three of:

(a) energy consumed by the coolant pump;

(b) variations in coolant temperature; and

(c) fan activation over the prediction horizon.

7. A method according to claim 5 wherein the act of determining coolant pump control signals and thermostat control signals are performed for plural discrete segments of the prediction horizon so as to minimize at least the sum of:

(a) energy consumed by the coolant pump;

(b) variations in coolant temperature; and

(c) fan activation for each of the discrete segments.

8. A method according to claim 7 wherein the act of determining coolant pump and thermostat control signals comprises determining a search space for coolant temperature that, at an upper temperature level, is no greater than Tc_max, wherein Tc_max is a maximum coolant temperature in the search space and is below a fan activation coolant temperature at which a vehicle fan would be activated, the search space having a lower temperature level Tc_min, the method comprising determining coolant pump and thermostat control signals that result in the temperature of the coolant falling within the search space during at least certain segments of the prediction horizon.