Electrical isolation system for a fuel cell stack and method of operating a fuel cell stack
US6764782B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 13, 2002 |
| Grant date | Jul 20, 2004 |
| Priority date | — |
| Expiry date | Sep 1, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E60/50
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electrical isolation system is provided for a fuel cell stack as well as a method of operating the fuel cell stack. The stack comprises a plurality of fuel cells connected in series and a coolant circuit for cooling said fuel cells in operation using a liquid coolant having a restricted electrical conductivity. The stack is associated with a chassis having a chassis ground and comprising a plurality of coolant passages for said fuel cells. The coolant circuit comprises a plurality of conductive components such as an outer boundary wall of the fuel cell stack, a radiator and/or a pump at least one of which is connected to said chassis ground. A measuring circuit is provided for measuring the resistance between a selected one of the fuel cells and the chassis ground and a monitoring circuit provides a warning signal, or disengages the connection to the output terminals of the stack or shuts down the stack if the resistance reaches a critical value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.