The present invention provides an apparatus and method for determining the concentration of CO gas in a fuel reformate stream such as in a PEM fuel cell vehicle. This invention protects the fuel cell catalyst by controlling the reformate stream system to minimize the CO and reduce it by a novel catalyst system that selectively converts CO to methane but does not react with carbon dioxide and hydrogen. The catalyst may reduce the CO to methane by reaction with hydrogen. The preferred embodiment both monitors the CO by a thermal differential sensing means and an optical biomimetic sensor and or a conductivity sensor. These sensors respond to the CO gas and are monitored by one or more monitoring sensors such as the temperature and or conductivity difference between the control and the catalytic material such as nickel and in the biomimetic sensor an optical change is monitored. The optical sensing comprising a photon source optically coupled to the sensor and photodiode system, so that the photon flux is a function of at least one other sensor's response to the CO gas, e.g., transmits light through the sensor to the photodiode. The photocurrent from the photodiode is converted to a digital sensor reading value proportional to the optical characteristic(s) of the sensor(s) as a function of time and the data is loaded into a microprocessor or other logic circuit. In the microprocessor, the sensor readings are essentially used to calculate the CO concentration and control the process to maximize the fuel cell or to trigger a signal for service.
RELATION TO COPENDING PATENT APPLICATION
This application claims benefit of U.S. Provisional Patent Application Serial No. 60/116,323 filed on Jan. 19, 1999, which application is incorporated herein by reference.
A fuel cell system has a reformer unit (1) for generating a reformate which is provided as a fuel for a fuel cell unit (4). The fuel cell system includes a sensor (5, 6, 7) for monitoring the quality of the reformate and a valve (9, 10) which can be controlled in dependence upon the sensor. Compared to conventional systems, the valve can react very rapidly to disturbances in the preparation of the reformate and can especially prevent that disturbances lead to damage of the fuel cell unit (4) and the electrical output power of the fuel cell unit continues to be controllable. This is achieved in that at least one storage unit (11) is provided for feeding fuel to the fuel cell unit (4) in dependence upon the quality of the reformate.
In order to provide a step capable of reliably detecting a CO concentration in a reformed gas at low cost and a hydrogen purifier capable of fully exerting a function of a CO purifying catalyst, a gas concentration detector comprising a reaction chamber which has a catalyst layer and a gas temperature detector and capable of detecting the concentration of carbon monoxide in the gas by means of a signal of the temperature detector referring to a reformed gas passing along through the reaction chamber.
A safety system for a gas-operated apparatus for generating energy, in particular in a vehicle, includes at least one sensor for measuring the gas concentration. The sensor is preferably disposed in the passenger compartment of the vehicle. In the event of a dangerously high gas concentration, a fan and/or power window control is triggered via a control unit in such a way that the fastest possible air exchange in the passenger compartment of the vehicle results.
A recreational vehicle includes a chassis having a living space, an electrical system for providing electrical power to the living space, an air conditioner for cooling the living space, a heater for heating the living space, and a plurality of appliances within the living space attached to the electrical system. The recreational vehicle also includes an engine for moving the recreational vehicle, a motor generator for supplying power to the recreational vehicle, a connector for connecting the electrical system of the recreational vehicle to an external power source, and a local area network system electrically connected to the air conditioner, the heater, the plurality of appliances, and the motor generator. The local area network manages the power provided to the to the electrical appliances. A display positioned within the living space shows data related to the air conditioner, the heater, the plurality of appliances, the motor generator and the engine.
The present invention provides an apparatus and method for determining the presence and/or concentration gases using an optical response. These sensors may be very small, fast and low-cost. The preferred embodiment of the invention is accomplished by means of photon monitoring one or more sensors that respond to the target gas. For example by 1) passing the photons through the sensor, 2) multi-passes of a photon beam through the sensor, 3) by evanescent field absorption (EFA) and 4) by using index of refraction changes to switch the photon from one path to another. Rapid detection of gases such as CO can be made by multiple passes of photons through a sensor that is absorbing photons of that wavelength range. The photon beam is passed back and forth through the sensor by some means such as using highly reflective optical surfaces or cavity. In essences the multiple internal reflections in a waveguide are similar to the multi-pass photon method except chat the evanescent method only penetrates about 200 nm. The EFA detection system comprises a photon source optically coupled to the sensor and photodiode system, so that the photon flux is a function of at least one other sensor's response to the target gas, e.g., transmits light through the sensor to the photodiode. In addition, a sensor that changes its index upon exposure to a target gas such CO may be used to switch photons from one waveguide to another proportional to the index changes which is in tern proportional to the concentration of the target gas. Each waveguide may have a different index of refraction and the sensor is in close proximity to both waveguides.
