The customer is the innovative company SIQENS, which uses the special solution in its fuel cell application. Possible industrial applications for off-grid energy include measurement technology, the construction industry or monitoring in remote regions and countryside where access to the public or regulated power supply is not guaranteed.
AUTRONIC already has experience in the development and production of power supplies for fuel cells since 2005. In this new project, new requirements were set for the development. Among others an input current of up to 100 A and a high efficiency of up to 97 % at an output power of 450 W. The implementation was done with the already proven polyphase design. To achieve high efficiency, the booster topology works without diodes, but exclusively with synchronized mosfets. Due to the careful selection of the switching mosfets and the storage chokes even an efficiency of 97 % could be realized and thus the development target was exceeded by 1 %.
The high efficiency has the highest positional value for the customer because it means that fewer cells are needed for the same output power and therefore less airflow is required to cool the assembly. Fuel cell technology and battery charging technology require a great deal of intelligence to achieve the best possible performance.
For this reason, the converter offers a lot of features:
The input and output of the values is digital to increase the accuracy and robustness of the entire system. The converters are equipped with an early fault detection for undervoltage, overvoltage, overcurrent and overtemperature to immediately detect possible faults in the overall system. The integrated error message when the converter goes into voltage mode serves to operate the fuel cell exactly at MPP (Maximum Power Point) and to achieve maximum possible power.
The converter is designed for the input voltage from 8,5 V to 40 V and for 24 V battery voltage. The output voltage can be adjusted from 40 V to 64 V. With the enable signal the converter is started and the fuel cell can be disconnected.