Development of the FC system for new generation FC Bus 2019-01-0372
Toyota Motor Corporation (TMC) has actively been pursuing the development of fuel cell vehicles (FCVs) to respond to global environmental concerns and demands for clean energy. Toyota developed the first fuel cell bus to receive vehicle type certification of Japan. New FC bus has adapted two FC systems and four High Voltage Batteries to meet its requirement of high power performance and durability. FC system is controlled to maximize usage of high voltage batteries and reduce the number of electric potential change of the fuel cell for high durability. To reduce the number of electric potential change of the fuel cell, voltage of the FC stack has to kept high and as a result FC power need to be kept low. High voltage batteries were used proactively to minimize the FC power during acceleration.
When the high voltage battery cannot supply power because of low battery SOC such as long hill-climbing, lower limit of FC voltage is low temporally and FC Power increase.
The life time durability test was initiated also including some of the conditions that the high voltage battery cannot supply power .As a result, FC power reduction rate after life time durability test is improve.