The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 15, 2009
Filed:
Dec. 15, 2005
Oliver Maier, Worms, DE;
Peter Willimowski, Darmstadt, DE;
Oliver Maier, Worms, DE;
Peter Willimowski, Darmstadt, DE;
GM Global Technology Operations, Inc., Detroit, MI (US);
Abstract
A control algorithm for a by-pass valve in a thermal sub-system of a fuel cell system, where the by-pass valve includes a wax element that is heated by a heating element. A stack power loss is applied to a PDT1 controller that associates a PDT dynamic function to the loss. The difference between the desired temperature of the stack and the actual temperature of the stack is applied to a PI controller that provides an error value of the difference. The actual temperature of the stack is applied to a look-up table that provides a value based on how close the actual temperature is to the opening temperature of the wax element. The values from the PDT1 controller, the PI controller and the look-up table are added to provide an output signal to control the current applied to the heater element, and thus, the heat applied to the wax element.