Patent ID: 8722218
Filing Date: 2014-05-13
Classification: H01M,Y02E,Y02T

Abstract:
1. A fuel cell system comprising: a first split sub-stack; a second split sub-stack; a bleed manifold unit (BMU) provided at the input of the first and second split sub-stacks, said bleed manifold unit including a first bleed valve, a second bleed valve, an exhaust valve, a flow restriction and a pressure sensor, said pressure sensor being coupled across the flow restriction and providing a pressure signal indicating flow through the flow restriction; and a controller that is programmed for determining whether flow paths in the BMU are blocked, said controller opening the first bleed valve, closing the second bleed valve and opening the exhaust valve, and reading the pressure signal from the pressure sensor to determine whether there is a pressure drop across the flow restriction, indicating flow through the flow restriction where if no flow is detected then one of the first bleed valve or the exhaust valve is blocked, said controller further programmed for closing the exhaust valve, leaving the first bleed valve open, and reading the pressure signal to determine the pressure drop across the flow restriction where a non-zero flow shows a restriction in the flow restriction or pressure sensor lines, said controller further programmed for closing the first bleed valve and opening the second bleed valve to determine whether the pressure signal indicates a flow through the second bleed valve.