Multiple fuel cell radiator system
AssigneeToyota Motor Engineering & Manufacturing North America, Inc.
InventorsLuke A. Rippelmeyer, Yohei Okamoto, Daniel Charles Folick, Jared Farnsworth
Life of this patent
Estimating the term…
Abstract
Systems and methods are provided for monitoring and controlling pump speeds to maintain a balanced pressure drop between each of the multiple fuel cell systems or circuits. In systems where a single radiator is used to maintain desired temperatures of multiple fuel cells, back flow can nevertheless be avoided. Control maps may be used to meet minimum pump speeds as a function of a flow splitting valve position and target flow rate (to prevent or avoid fluid back flow through a fuel cell stack). Control maps may also be used to determine a minimum pump speed as a function of three-way valve position (to prevent fluid back flow across a radiator path).
Claims11
A method comprising:
- determining minimum pump speeds at which first and second pumps of a cooling system may operate to prevent backflow in the cooling system;
- determining amounts by which first and second flow splitting valves of the cooling system may be opened to, in conjunction with the first and second pumps, prevent backflow in the cooling system, wherein:
- the amounts by which the first and second flow splitting valves may be opened are determined by estimating operating states of components of the cooling system including the first and second pumps and the first and second flow splitting valves, and back-calculating for the amounts based on at least one of:
- (a) mathematical representations of the components of the cooling system, or (b) values derived from the mathematical representations, and
- a respective mathematical representation comprises at least one of:
- (a) an equation used to represent physical characteristics of a respective component of the cooling system, or (b) a state estimator that predicts an operational state of the respective component;
- and
- operating the first and second pumps at the determined minimum pump speeds and operating the first and second flow splitting valves in accordance with the determined amounts by which first and second flow splitting valves of the cooling system may be opened.
A system, comprising:
- one or more processors;
- and
- memory including instructions that when executed by the one or processors, cause the system to:
- determine minimum pump speeds at which first and second pumps may operate to prevent backflow in a cooling system, the first and second pumps pumping coolant through first and second fuel cell systems;
- determine amounts by which first and second flow splitting valves of the first and second fuel cell systems, respectively, may be opened to, in conjunction with the first and second pumps, prevent backflow within paths of the system defined relative to a single common radiator through which the coolant passes, wherein:
- the amounts by which the first and second flow splitting valves may be opened are determined by estimating operating states of the first and second pumps and the first and second flow splitting valves, and back-calculating for the amounts based on at least one of:
- (a) mathematical representations of each of the first and second pumps, the first and second flow splitting valves, and the single common radiator, and (b) values derived from the mathematical representations, and
- a respective mathematical representation comprises at least one of:
- (a) a physical equation used to represent physical characteristics of a respective component, and (b) a state estimator that predicts an operational state of the respective component;
- and
- operate the first and second pumps at the determined minimum pump speeds and operate the first and second flow splitting valves in accordance with the determined amounts by which first and second flow splitting valves of the cooling system may be opened.
Dependencies are inferred from the claim text.